feat(frontend): analytics shows minutes online by hour of week and by day, sessions with start and end, says when last seen is hidden, chat status is live and in russian

README.md

@@ -24,7 +24,7 @@ Nothing is ever deleted from the archive.
 
 ## MCP
 
-Read-only: `list_watched_bots`, `get_bot_stats`, `get_bot_updates`, `search_messages_tool`, `list_chats`, `get_chat_history` (with deleted messages included), `get_deleted_messages`, `get_message_versions`, `get_media`, `get_callbacks`, `presence_history`, `get_peer_history`, `get_stories`, `get_annotations`, `list_watches`, `list_alerts`. The one write is `set_watch`. There are no send, edit or delete tools and there will not be.
+Read-only: `list_watched_bots`, `get_bot_stats`, `get_bot_updates`, `search_messages_tool`, `list_chats`, `get_chat_history` (with deleted messages included), `get_deleted_messages`, `get_message_versions`, `get_media`, `get_callbacks`, `presence_history`, `presence_stats`, `get_peer_history`, `get_stories`, `get_annotations`, `list_watches`, `list_alerts`. The one write is `set_watch`. There are no send, edit or delete tools and there will not be.
 
 ## Run
 

backend/migrations/versions/d7a3c5e9f2b1_message_reads.py

@@ -0,0 +1,51 @@
+"""message reads
+
+Revision ID: d7a3c5e9f2b1
+Revises: f8c2d6e1a4b7
+Create Date: 2026-10-19 01:00:00.000000
+
+"""
+
+from collections.abc import Sequence
+
+from alembic import op
+
+revision: str = "d7a3c5e9f2b1"
+down_revision: str | None = "f8c2d6e1a4b7"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+_READS = """
+CREATE TABLE message_reads (
+    account_id integer NOT NULL,
+    chat_id bigint NOT NULL,
+    message_id bigint NOT NULL,
+    reader_id bigint NOT NULL,
+    read_at timestamptz NOT NULL,
+    source text NOT NULL,
+    fetched_at timestamptz NOT NULL DEFAULT now(),
+    PRIMARY KEY (account_id, chat_id, message_id, reader_id)
+)
+"""
+
+_FETCHES = """
+CREATE TABLE read_fetches (
+    account_id integer NOT NULL,
+    chat_id bigint NOT NULL,
+    message_id bigint NOT NULL,
+    outcome text NOT NULL,
+    fetched_at timestamptz NOT NULL DEFAULT now(),
+    retry_at timestamptz NOT NULL,
+    PRIMARY KEY (account_id, chat_id, message_id)
+)
+"""
+
+
+def upgrade() -> None:
+    op.execute(_READS)
+    op.execute(_FETCHES)
+
+
+def downgrade() -> None:
+    op.execute("DROP TABLE IF EXISTS read_fetches")
+    op.execute("DROP TABLE IF EXISTS message_reads")

backend/migrations/versions/d8f4a1c6e2b7_capture_uptime.py

@@ -0,0 +1,50 @@
+"""capture uptime
+
+Revision ID: d8f4a1c6e2b7
+Revises: d7a3c5e9f2b1
+Create Date: 2026-10-19 03:00:00.000000
+
+"""
+
+from collections.abc import Sequence
+
+from alembic import op
+
+revision: str = "d8f4a1c6e2b7"
+down_revision: str | None = "d7a3c5e9f2b1"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+_UPTIME = """
+CREATE TABLE capture_uptime (
+    account_id integer NOT NULL,
+    started_at timestamptz NOT NULL,
+    seen_at timestamptz NOT NULL,
+    PRIMARY KEY (account_id, started_at)
+)
+"""
+
+_BACKFILL = """
+INSERT INTO capture_uptime (account_id, started_at, seen_at)
+SELECT account_id, min(ts), max(ts)
+FROM (
+    SELECT account_id, ts,
+           count(*) FILTER (WHERE gap > interval '30 minutes')
+               OVER (PARTITION BY account_id ORDER BY ts) AS stretch
+    FROM (
+        SELECT account_id, ts,
+               ts - lag(ts) OVER (PARTITION BY account_id ORDER BY ts) AS gap
+        FROM presence
+    ) gaps
+) stretches
+GROUP BY account_id, stretch
+"""
+
+
+def upgrade() -> None:
+    op.execute(_UPTIME)
+    op.execute(_BACKFILL)
+
+
+def downgrade() -> None:
+    op.execute("DROP TABLE IF EXISTS capture_uptime")

backend/src/api/mcp/server.py

@@ -20,9 +20,20 @@ from api.mcp.download import (
 from api.mcp.format import build_transcript, load_notes, load_photos, resolve_names
 from dependencies.container import container
 from utils.files import resolve_mime
-from utils.read import annotations, chats, media, peers, presence, social, watches
+from utils.read import (
+    annotations,
+    chats,
+    media,
+    peers,
+    presence,
+    presence_stats,
+    social,
+    watches,
+)
 from utils.read.accounts import self_user_id, unknown_account_hint
 from utils.read.models import DEFAULT_LIMIT, Page
+from utils.read.period import DEFAULT_TZ, MAX_DAYS, known_timezone
+from utils.read.read_receipts import read_info
 from utils.search.models import SearchFilters
 from utils.search.repository import search_messages
 from utils.storage import ContentAddressedStorage
@@ -295,6 +306,23 @@ async def get_callbacks(
     return _dump(items)
 
 
+@mcp.tool
+async def get_read_info(
+    account_id: int, chat_id: int, message_id: int
+) -> dict[str, Any] | None:
+    """When the user's own message was read, from the archive only.
+
+    `observed_at` is when the archive saw the chat read up to this message,
+    `exact_at` the read date Telegram reported for a private chat, `readers`
+    who read it in a group and when, `listened_at` when a voice or round
+    video was played. `outcome` is the last Telegram answer: ok, not_read_yet,
+    user_privacy (they hide read time), your_privacy (the user hides theirs),
+    chat_too_big, too_old, unavailable, flood or error.
+    """
+    info = await read_info(await _pool(), account_id, chat_id, message_id)
+    return info.model_dump(mode="json") if info else None
+
+
 @mcp.tool
 async def presence_history(
     account_id: int,
@@ -317,6 +345,37 @@ async def presence_history(
     )
 
 
+@mcp.tool(name="presence_stats")
+async def presence_stats_tool(
+    account_id: int,
+    peer_id: int,
+    days: int = 30,
+    tz: str = DEFAULT_TZ,
+    limit: int = DEFAULT_LIMIT,
+    offset: int = 0,
+) -> dict[str, Any]:
+    """Time a peer spent online, from status pushes turned into online sessions.
+
+    `tz` is an IANA zone name; days and hours are counted in it. `week` holds
+    the average online minutes for each weekday (0 is Monday) and hour, null
+    where the archive has no data for that hour. `days` gives online seconds
+    per day, `gaps` the stretches when capture was down, `sessions` the latest
+    sessions (online stretches with breaks under 5 minutes), paged by
+    `limit`/`offset`. `hidden` means the peer hides their last seen time.
+    """
+    pool = await _pool()
+    if not 1 <= days <= MAX_DAYS:
+        msg = f"days must be between 1 and {MAX_DAYS}"
+        raise ToolError(msg)
+    if not await known_timezone(pool, tz):
+        msg = f"Unknown time zone: {tz}"
+        raise ToolError(msg)
+    stats = await presence_stats.presence_stats(
+        pool, account_id, peer_id, Page(limit=limit, offset=offset), days=days, tz=tz
+    )
+    return stats.model_dump(mode="json")
+
+
 @mcp.tool
 async def get_peer_history(account_id: int, peer_id: int) -> list[dict[str, Any]]:
     """Get name/username/avatar change history of a contact."""

backend/src/api/realtime.py

@@ -1,6 +1,7 @@
 import asyncio
 import json
 import logging
+from datetime import UTC, datetime
 from typing import Any
 
 import asyncpg
@@ -58,16 +59,12 @@ class EventHub:
             return
         account_id = event.get("account_id")
         chat_id = event.get("chat_id")
-        scoped = event.get("kind") == "presence"
+        account_wide = event.get("kind") == "presence"
         targets = [
             sub
             for sub in self._subscribers
             if sub.account_id == account_id
-            and (
-                sub.chat_id == chat_id
-                if scoped
-                else sub.chat_id is None or sub.chat_id == chat_id
-            )
+            and (account_wide or sub.chat_id is None or sub.chat_id == chat_id)
         ]
         if not targets:
             return
@@ -114,6 +111,7 @@ class EventHub:
                 "type": "receipt",
                 "chat_id": event["chat_id"],
                 "read_up_to": event["message_id"],
+                "read_at": datetime.now(UTC).isoformat(),
             }
         return None
 

backend/src/api/routers/analytics.py

@@ -4,8 +4,10 @@ import asyncpg
 from dishka.integrations.fastapi import DishkaRoute, FromDishka
 from fastapi import APIRouter, Query
 
+from api.timezone import checked_tz
 from utils.read import analytics
 from utils.read.models import ResponseStats, VolumeBucket
+from utils.read.period import DEFAULT_TZ, MAX_DAYS
 
 router = APIRouter(prefix="/api/analytics", tags=["analytics"], route_class=DishkaRoute)
 
@@ -18,9 +20,12 @@ async def volume(
     pool: FromDishka[asyncpg.Pool],
     account_id: AccountId,
     chat_id: ChatId,
-    days: Annotated[int, Query()] = 90,
+    days: Annotated[int, Query(ge=1, le=MAX_DAYS)] = 90,
+    tz: Annotated[str, Query()] = DEFAULT_TZ,
 ) -> list[VolumeBucket]:
-    return await analytics.message_volume(pool, account_id, chat_id, days=days)
+    return await analytics.message_volume(
+        pool, account_id, chat_id, days=days, tz=await checked_tz(pool, tz)
+    )
 
 
 @router.get("/response-time")

backend/src/api/routers/presence.py

@@ -5,8 +5,17 @@ import asyncpg
 from dishka.integrations.fastapi import DishkaRoute, FromDishka
 from fastapi import APIRouter, Query
 
-from utils.read import presence
-from utils.read.models import DEFAULT_LIMIT, Page, PresenceHourly, PresenceSample
+from api.timezone import checked_tz
+from utils.read import presence, presence_stats
+from utils.read.models import (
+    DEFAULT_LIMIT,
+    Page,
+    PresenceHourly,
+    PresenceSample,
+    PresenceSession,
+    PresenceStats,
+)
+from utils.read.period import DEFAULT_TZ, MAX_DAYS
 
 router = APIRouter(prefix="/api/presence", tags=["presence"], route_class=DishkaRoute)
 
@@ -14,6 +23,8 @@ AccountId = Annotated[int, Query()]
 PeerId = Annotated[int, Query()]
 DateFrom = Annotated[datetime | None, Query()]
 DateTo = Annotated[datetime | None, Query()]
+Days = Annotated[int, Query(ge=1, le=MAX_DAYS)]
+Tz = Annotated[str, Query()]
 
 
 @router.get("")
@@ -54,3 +65,43 @@ async def presence_hourly(
     return await presence.presence_hourly(
         pool, account_id, peer_id, date_from=date_from, date_to=date_to
     )
+
+
+@router.get("/stats")
+async def stats(
+    pool: FromDishka[asyncpg.Pool],
+    account_id: AccountId,
+    peer_id: PeerId,
+    days: Days = 30,
+    tz: Tz = DEFAULT_TZ,
+    limit: Annotated[int, Query()] = DEFAULT_LIMIT,
+    offset: Annotated[int, Query()] = 0,
+) -> PresenceStats:
+    return await presence_stats.presence_stats(
+        pool,
+        account_id,
+        peer_id,
+        Page(limit=limit, offset=offset),
+        days=days,
+        tz=await checked_tz(pool, tz),
+    )
+
+
+@router.get("/sessions")
+async def sessions(
+    pool: FromDishka[asyncpg.Pool],
+    account_id: AccountId,
+    peer_id: PeerId,
+    days: Days = 30,
+    tz: Tz = DEFAULT_TZ,
+    limit: Annotated[int, Query()] = DEFAULT_LIMIT,
+    offset: Annotated[int, Query()] = 0,
+) -> list[PresenceSession]:
+    return await presence_stats.presence_sessions(
+        pool,
+        account_id,
+        peer_id,
+        Page(limit=limit, offset=offset),
+        days=days,
+        tz=await checked_tz(pool, tz),
+    )

backend/src/api/routers/social.py

@@ -2,10 +2,13 @@ from typing import Annotated
 
 import asyncpg
 from dishka.integrations.fastapi import DishkaRoute, FromDishka
-from fastapi import APIRouter, Query
+from fastapi import APIRouter, HTTPException, Query
+from pydantic import BaseModel
 
+from utils.jobs import enqueue
 from utils.read import social
-from utils.read.models import CallbackView, LinkView, ReactionView
+from utils.read.models import CallbackView, LinkView, ReactionView, ReadInfoView
+from utils.read.read_receipts import read_info
 
 router = APIRouter(
     prefix="/api/messages/{chat_id}/{message_id}",
@@ -16,6 +19,10 @@ router = APIRouter(
 AccountId = Annotated[int, Query()]
 
 
+class RefreshRequest(BaseModel):
+    account_id: int
+
+
 @router.get("/callbacks")
 async def message_callbacks(
     pool: FromDishka[asyncpg.Pool], chat_id: int, message_id: int, account_id: AccountId
@@ -35,3 +42,29 @@ async def message_links(
     pool: FromDishka[asyncpg.Pool], chat_id: int, message_id: int, account_id: AccountId
 ) -> list[LinkView]:
     return await social.get_links(pool, account_id, chat_id, message_id)
+
+
+@router.get("/read")
+async def message_read(
+    pool: FromDishka[asyncpg.Pool], chat_id: int, message_id: int, account_id: AccountId
+) -> ReadInfoView:
+    info = await read_info(pool, account_id, chat_id, message_id)
+    if info is None:
+        raise HTTPException(status_code=404, detail="message not found")
+    return info
+
+
+@router.post("/read/refresh")
+async def refresh_message_read(
+    pool: FromDishka[asyncpg.Pool], chat_id: int, message_id: int, body: RefreshRequest
+) -> dict[str, int | None]:
+    info = await read_info(pool, body.account_id, chat_id, message_id)
+    if info is None or not info.can_fetch:
+        return {"job_id": None}
+    job_id = await enqueue(
+        pool,
+        body.account_id,
+        "fetch_read_info",
+        {"chat_id": chat_id, "message_id": message_id},
+    )
+    return {"job_id": job_id}

backend/src/api/timezone.py

@@ -0,0 +1,10 @@
+import asyncpg
+from fastapi import HTTPException
+
+from utils.read.period import known_timezone
+
+
+async def checked_tz(pool: asyncpg.Pool, tz: str) -> str:
+    if not await known_timezone(pool, tz):
+        raise HTTPException(status_code=422, detail=f"Unknown time zone: {tz}")
+    return tz

backend/src/userbot/handlers/raw/read_receipts.py

@@ -7,25 +7,35 @@ from userbot.modules.raw_json import raw_json
 from userbot.modules.read_receipts import repository
 from utils.events import notify_bg_event
 
-HANDLES = (raw.types.UpdateReadHistoryOutbox,)
+HANDLES = (raw.types.UpdateReadHistoryOutbox, raw.types.UpdateReadChannelOutbox)
+
+
+def _watermark(update: raw.base.Update) -> tuple[int, int] | None:
+    if isinstance(update, raw.types.UpdateReadHistoryOutbox):
+        return utils.get_peer_id(update.peer), update.max_id
+    if isinstance(update, raw.types.UpdateReadChannelOutbox):
+        peer = raw.types.PeerChannel(channel_id=update.channel_id)
+        return utils.get_peer_id(peer), update.max_id
+    return None
 
 
 async def handle(
     client: PyroClient, update: raw.base.Update, _users: dict, _chats: dict
 ) -> None:
     ctx = client.capture
-    if ctx is None or not isinstance(update, raw.types.UpdateReadHistoryOutbox):
+    watermark = _watermark(update)
+    if ctx is None or watermark is None:
         return
-    chat_id = utils.get_peer_id(update.peer)
+    chat_id, max_id = watermark
     await repository.insert_read(
         ctx.pool,
         ctx.account_id,
         chat_id,
         chat_id,
         datetime.now(UTC),
-        update.max_id,
+        max_id,
         raw_json(update),
     )
     await notify_bg_event(
-        ctx.pool, "receipt", ctx.account_id, chat_id=chat_id, message_id=update.max_id
+        ctx.pool, "receipt", ctx.account_id, chat_id=chat_id, message_id=max_id
     )

backend/src/userbot/modules/jobs/handlers/__init__.py

@@ -5,6 +5,7 @@ from userbot.modules.jobs.handlers import (
     fetch_avatar,
     fetch_custom_emoji,
     fetch_media,
+    fetch_read_info,
     search_peers,
     sync_contacts,
     sync_dialogs,
@@ -18,6 +19,7 @@ __all__ = [
     "fetch_avatar",
     "fetch_custom_emoji",
     "fetch_media",
+    "fetch_read_info",
     "search_peers",
     "sync_contacts",
     "sync_dialogs",

backend/src/userbot/modules/jobs/handlers/fetch_read_info.py

@@ -0,0 +1,124 @@
+from datetime import UTC, datetime, timedelta
+
+from pyrogram import Client, raw
+from pyrogram.errors import (
+    ChannelInvalid,
+    ChannelPrivate,
+    ChatTooBig,
+    FloodPremiumWait,
+    FloodWait,
+    MessageIdInvalid,
+    MessageNotReadYet,
+    MessageTooOld,
+    MsgIdInvalid,
+    MsgTooOld,
+    PeerIdInvalid,
+    RPCError,
+    UserPrivacyRestricted,
+    YourPrivacyRestricted,
+)
+
+from userbot.modules.jobs.context import JobContext
+from userbot.modules.jobs.registry import register
+from userbot.modules.read_receipts.repository import save_fetch, save_reads
+from utils.jobs import enqueue
+from utils.logging import logger
+from utils.policy.models import ChatKind
+from utils.read.peers import get_peers
+from utils.read.read_receipts import read_info
+
+RETRY = timedelta(seconds=60)
+LATER = timedelta(days=1)
+
+Refusal = tuple[tuple[type[Exception], ...], str, timedelta]
+
+REFUSALS: tuple[Refusal, ...] = (
+    ((MessageNotReadYet,), "not_read_yet", RETRY),
+    ((UserPrivacyRestricted,), "user_privacy", RETRY),
+    ((YourPrivacyRestricted,), "your_privacy", LATER),
+    ((ChatTooBig,), "chat_too_big", LATER),
+    ((MsgTooOld, MessageTooOld), "too_old", LATER),
+    (
+        (
+            PeerIdInvalid,
+            ChannelInvalid,
+            ChannelPrivate,
+            MessageIdInvalid,
+            MsgIdInvalid,
+            KeyError,
+            ValueError,
+        ),
+        "unavailable",
+        RETRY,
+    ),
+)
+
+
+def _refusal(exc: Exception) -> tuple[str, timedelta]:
+    for kinds, outcome, retry in REFUSALS:
+        if isinstance(exc, kinds):
+            return outcome, retry
+    return "error", RETRY
+
+
+def _at(timestamp: int) -> datetime:
+    return datetime.fromtimestamp(timestamp, UTC)
+
+
+async def ask_telegram(
+    client: Client, chat_id: int, message_id: int, *, group: bool
+) -> list[tuple[int, datetime]]:
+    peer = await client.resolve_peer(chat_id)
+    if peer is None:
+        msg = f"unknown peer {chat_id}"
+        raise ValueError(msg)
+    if group:
+        participants = await client.invoke(
+            raw.functions.messages.GetMessageReadParticipants(
+                peer=peer, msg_id=message_id
+            )
+        )
+        return [(item.user_id, _at(item.date)) for item in participants]
+    outbox = await client.invoke(
+        raw.functions.messages.GetOutboxReadDate(peer=peer, msg_id=message_id)
+    )
+    return [(chat_id, _at(outbox.date))]
+
+
+async def _enrich_unknown(ctx: JobContext, chat_id: int, reader_ids: list[int]) -> None:
+    known = {
+        peer.peer_id for peer in await get_peers(ctx.pool, ctx.account_id, reader_ids)
+    }
+    if set(reader_ids) - known:
+        await enqueue(ctx.pool, ctx.account_id, "enrich_chat", {"chat_id": chat_id})
+
+
+@register("fetch_read_info")
+async def fetch_read_info(ctx: JobContext) -> None:
+    client = ctx.client
+    if client is None:
+        return
+    chat_id = ctx.job.params["chat_id"]
+    message_id = ctx.job.params["message_id"]
+    info = await read_info(ctx.pool, ctx.account_id, chat_id, message_id)
+    if info is None or not info.can_fetch:
+        return
+    group = info.chat_kind == ChatKind.GROUP
+    try:
+        reads = await ask_telegram(client, chat_id, message_id, group=group)
+    except (FloodWait, FloodPremiumWait) as exc:
+        wait = exc.value if isinstance(exc.value, int) else 0
+        retry = max(RETRY, timedelta(seconds=wait))
+        await save_fetch(ctx.pool, ctx.account_id, chat_id, message_id, "flood", retry)
+        return
+    except (RPCError, KeyError, ValueError) as exc:
+        outcome, retry = _refusal(exc)
+        if outcome == "error":
+            logger.warning(f"[yellow]Read info {chat_id}/{message_id}: {exc!r}[/]")
+        await save_fetch(ctx.pool, ctx.account_id, chat_id, message_id, outcome, retry)
+        return
+    source = "participants" if group else "outbox_date"
+    await save_reads(ctx.pool, ctx.account_id, chat_id, message_id, source, reads)
+    await save_fetch(ctx.pool, ctx.account_id, chat_id, message_id, "ok", RETRY)
+    if group and reads:
+        await _enrich_unknown(ctx, chat_id, [reader_id for reader_id, _ in reads])

backend/src/userbot/modules/read_receipts/repository.py

@@ -1,4 +1,4 @@
-from datetime import datetime
+from datetime import datetime, timedelta
 
 import asyncpg
 
@@ -9,6 +9,26 @@ VALUES ($1, $2, $3, $4, $5, $6, $7::jsonb)
 ON CONFLICT (account_id, chat_id, message_id, ts) DO NOTHING
 """
 
+_UPSERT_READ = """
+INSERT INTO message_reads
+    (account_id, chat_id, message_id, reader_id, read_at, source, fetched_at)
+VALUES ($1, $2, $3, $4, $5, $6, now())
+ON CONFLICT (account_id, chat_id, message_id, reader_id) DO UPDATE SET
+    read_at = EXCLUDED.read_at,
+    source = EXCLUDED.source,
+    fetched_at = EXCLUDED.fetched_at
+"""
+
+_UPSERT_FETCH = """
+INSERT INTO read_fetches
+    (account_id, chat_id, message_id, outcome, fetched_at, retry_at)
+VALUES ($1, $2, $3, $4, now(), now() + $5::interval)
+ON CONFLICT (account_id, chat_id, message_id) DO UPDATE SET
+    outcome = EXCLUDED.outcome,
+    fetched_at = EXCLUDED.fetched_at,
+    retry_at = EXCLUDED.retry_at
+"""
+
 
 async def insert_read(  # noqa: PLR0913
     pool: asyncpg.Pool,
@@ -34,3 +54,33 @@ async def insert_listened(  # noqa: PLR0913
     await pool.execute(
         _INSERT, account_id, chat_id, message_id, ts, reader_id, "listened", raw
     )
+
+
+async def save_reads(  # noqa: PLR0913
+    pool: asyncpg.Pool,
+    account_id: int,
+    chat_id: int,
+    message_id: int,
+    source: str,
+    reads: list[tuple[int, datetime]],
+) -> None:
+    await pool.executemany(
+        _UPSERT_READ,
+        [
+            (account_id, chat_id, message_id, reader_id, read_at, source)
+            for reader_id, read_at in reads
+        ],
+    )
+
+
+async def save_fetch(  # noqa: PLR0913
+    pool: asyncpg.Pool,
+    account_id: int,
+    chat_id: int,
+    message_id: int,
+    outcome: str,
+    retry_after: timedelta,
+) -> None:
+    await pool.execute(
+        _UPSERT_FETCH, account_id, chat_id, message_id, outcome, retry_after
+    )

backend/src/userbot/modules/uptime/repository.py

@@ -0,0 +1,16 @@
+import asyncpg
+
+_HEARTBEAT = """
+WITH extended AS (
+    UPDATE capture_uptime SET seen_at = now()
+    WHERE account_id = $1 AND seen_at >= now() - interval '150 seconds'
+    RETURNING account_id
+)
+INSERT INTO capture_uptime (account_id, started_at, seen_at)
+SELECT $1, now(), now()
+WHERE NOT EXISTS (SELECT 1 FROM extended)
+"""
+
+
+async def heartbeat(pool: asyncpg.Pool, account_id: int) -> None:
+    await pool.execute(_HEARTBEAT, account_id)

backend/src/userbot/runner.py

@@ -14,6 +14,7 @@ from userbot.modules.capture import CaptureContext, build_capture_context
 from userbot.modules.catchup import SavedState, catch_up, read_saved_state
 from userbot.modules.client import PyroClient
 from userbot.modules.jobs import JobConsumer
+from userbot.modules.uptime import repository as uptime
 from utils.env import env
 from utils.jobs import enqueue
 from utils.listen import Listener
@@ -31,6 +32,7 @@ setup_logging()
 
 SESSION_FLUSH_INTERVAL = 60
 SESSION_RETRY_INTERVAL = 60
+UPTIME_INTERVAL = 60
 
 
 @dataclass
@@ -171,6 +173,15 @@ async def _retry_sessions(registry: AccountRegistry) -> None:
             logger.exception("[red]Session sync failed[/]")
 
 
+async def _keep_uptime(registry: AccountRegistry, pool: asyncpg.Pool) -> None:
+    while True:
+        for client in registry.clients:
+            if client.capture is not None and client.is_connected:
+                with contextlib.suppress(Exception):
+                    await uptime.heartbeat(pool, client.capture.account_id)
+        await asyncio.sleep(UPTIME_INTERVAL)
+
+
 def _change_listener(registry: AccountRegistry, tasks: set[asyncio.Task]) -> Listener:
     def spawn(coro: Coroutine[Any, Any, None]) -> None:
         task = asyncio.create_task(coro)
@@ -220,6 +231,7 @@ async def runner() -> None:
     asyncio.get_running_loop().add_signal_handler(signal.SIGTERM, stop.set)
     flush = asyncio.create_task(_flush_sessions(registry))
     retry = asyncio.create_task(_retry_sessions(registry))
+    beat = asyncio.create_task(_keep_uptime(registry, pool))
     try:
         await registry.sync()
         if not registry.clients:
@@ -230,6 +242,7 @@ async def runner() -> None:
     finally:
         await _cancel(flush)
         await _cancel(retry)
+        await _cancel(beat)
         await listener.stop()
         await registry.close()
         await container.close()

backend/src/utils/read/analytics.py

@@ -4,23 +4,31 @@ import asyncpg
 
 from utils.read.accounts import self_user_id
 from utils.read.models import ResponseStats, VolumeBucket
+from utils.read.period import period_bounds
+
+_VOLUME = """
+WITH counts AS (
+    SELECT (date AT TIME ZONE $5)::date AS day, count(*) AS total,
+           count(*) FILTER (WHERE sender_id = $3) AS outgoing
+    FROM messages
+    WHERE account_id = $1 AND chat_id = $2 AND date >= $4
+    GROUP BY 1
+)
+SELECT local_day::date AS bucket, coalesce(total, 0) AS total,
+       coalesce(outgoing, 0) AS outgoing
+FROM generate_series(($4 AT TIME ZONE $5)::date, (now() AT TIME ZONE $5)::date,
+                     interval '1 day') AS local_day
+LEFT JOIN counts ON counts.day = local_day::date
+ORDER BY 1
+"""
 
 
 async def message_volume(
-    pool: asyncpg.Pool, account_id: int, chat_id: int, *, days: int = 90
+    pool: asyncpg.Pool, account_id: int, chat_id: int, *, days: int, tz: str
 ) -> list[VolumeBucket]:
     self_id = await self_user_id(pool, account_id)
-    rows = await pool.fetch(
-        "SELECT date_trunc('day', date) AS bucket, count(*) AS total, "
-        "count(*) FILTER (WHERE sender_id = $3) AS outgoing "
-        "FROM messages "
-        "WHERE account_id = $1 AND chat_id = $2 AND date >= $4 "
-        "GROUP BY bucket ORDER BY bucket",
-        account_id,
-        chat_id,
-        self_id,
-        datetime.now(UTC) - timedelta(days=days),
-    )
+    since, _ = await period_bounds(pool, days, tz)
+    rows = await pool.fetch(_VOLUME, account_id, chat_id, self_id, since, tz)
     return [
         VolumeBucket(
             bucket=row["bucket"],

backend/src/utils/read/chats.py

@@ -10,7 +10,7 @@ from utils.read.models import (
     MessageView,
     Page,
 )
-from utils.read.read_receipts import read_up_to
+from utils.read.read_receipts import read_times, read_up_to
 
 _MESSAGE_COLS = (
     "chat_id, message_id, date, sender_id, text, has_media, is_self_destruct, "
@@ -285,12 +285,18 @@ async def _apply_read_status(
     self_id = await self_user_id(pool, account_id)
     if self_id is None:
         return
-    marker = await read_up_to(pool, account_id, chat_id)
-    if marker is None:
+    own = [view for view in views if view.sender_id == self_id]
+    if not own:
         return
-    for view in views:
-        if view.sender_id == self_id and view.message_id <= marker:
-            view.read = True
+    marker = await read_up_to(pool, account_id, chat_id)
+    times = await read_times(
+        pool, account_id, chat_id, [(view.message_id, view.date) for view in own]
+    )
+    for view in own:
+        view.read_at = times.get(view.message_id)
+        view.read = view.read_at is not None or (
+            marker is not None and view.message_id <= marker
+        )
 
 
 def _build_album(

backend/src/utils/read/models.py

@@ -1,4 +1,4 @@
-from datetime import datetime
+from datetime import date, datetime
 from typing import Any
 
 from pydantic import BaseModel
@@ -203,6 +203,7 @@ class MessageView(BaseModel):
     is_sticker: bool = False
     is_animated_emoji: bool = False
     read: bool = False
+    read_at: datetime | None = None
 
 
 class MessageVersionView(BaseModel):
@@ -361,8 +362,61 @@ class PresenceHourly(BaseModel):
     last_seen: datetime | None
 
 
+class PresenceSession(BaseModel):
+    started: datetime
+    ended: datetime
+    seconds: float
+    online_seconds: float
+    ongoing: bool
+
+
+class PresenceHour(BaseModel):
+    weekday: int
+    hour: int
+    hours: int
+    online_minutes: float | None
+    covered_hours: float
+
+
+class PresenceDay(BaseModel):
+    day: date
+    online_seconds: float
+    covered_seconds: float
+
+
+class CoverageGap(BaseModel):
+    started: datetime
+    ended: datetime
+
+
+class PresenceSummary(BaseModel):
+    online_seconds: float
+    daily_seconds: float | None
+    covered_seconds: float
+    session_count: int
+    median_session_seconds: float | None
+    first_online: int | None
+    last_offline: int | None
+    last_seen: datetime | None
+
+
+class PresenceStats(BaseModel):
+    peer_id: int
+    tz: str
+    since: datetime
+    until: datetime
+    current: PresenceSample | None
+    online: bool
+    hidden: bool
+    summary: PresenceSummary
+    week: list[PresenceHour]
+    days: list[PresenceDay]
+    gaps: list[CoverageGap]
+    sessions: list[PresenceSession]
+
+
 class VolumeBucket(BaseModel):
-    bucket: datetime
+    bucket: date
     total: int
     outgoing: int
     incoming: int
@@ -387,6 +441,29 @@ class PeerView(BaseModel):
     updated_at: datetime
 
 
+class ReaderView(BaseModel):
+    peer_id: int
+    read_at: datetime
+    peer: PeerView | None
+
+
+class ReadInfoView(BaseModel):
+    chat_id: int
+    message_id: int
+    chat_kind: str
+    own: bool
+    voice: bool
+    observed_at: datetime | None
+    listened_at: datetime | None
+    exact_at: datetime | None
+    readers: list[ReaderView]
+    read: bool
+    unread: bool
+    outcome: str | None
+    fetched_at: datetime | None
+    can_fetch: bool
+
+
 class PeerHistoryView(BaseModel):
     observed_at: datetime
     first_name: str | None

backend/src/utils/read/period.py

@@ -0,0 +1,27 @@
+from datetime import datetime
+
+import asyncpg
+
+DEFAULT_TZ = "UTC"
+MAX_DAYS = 365
+
+_timezones: set[str] = set()
+
+
+async def known_timezone(pool: asyncpg.Pool, tz: str) -> bool:
+    if not _timezones:
+        rows = await pool.fetch("SELECT name FROM pg_timezone_names")
+        _timezones.update(row["name"] for row in rows)
+    return tz in _timezones
+
+
+async def period_bounds(
+    pool: asyncpg.Pool, days: int, tz: str
+) -> tuple[datetime, datetime]:
+    row = await pool.fetchrow(
+        "SELECT (date_trunc('day', now() AT TIME ZONE $1) "
+        "- make_interval(days => $2 - 1)) AT TIME ZONE $1 AS since, now() AS until",
+        tz,
+        days,
+    )
+    return row["since"], row["until"]

backend/src/utils/read/presence_stats.py

@@ -0,0 +1,289 @@
+import json
+
+import asyncpg
+
+from utils.read.models import (
+    CoverageGap,
+    Page,
+    PresenceDay,
+    PresenceHour,
+    PresenceSession,
+    PresenceStats,
+    PresenceSummary,
+)
+from utils.read.period import period_bounds
+from utils.read.presence import current_presence
+
+SECONDS_IN_HOUR = 3600
+SECONDS_IN_DAY = 86_400
+MIN_CELL_COVERAGE = 1800
+MIN_CELL_SHARE = 0.5
+STATS_WORK_MEM = "32MB"
+FUZZY_STATUSES = {"recently", "last_week", "last_month", "long_time_ago"}
+
+_SESSIONS = """
+marks AS (
+    SELECT ts, status,
+           least(next_offline_date, ts + interval '5 minutes',
+                 lead(coalesce(last_online_date, ts)) OVER w, $4) AS ended,
+           lag(CASE WHEN status = 'online'
+                    THEN least(next_offline_date, ts + interval '5 minutes')
+                    ELSE coalesce(last_online_date, ts) END) OVER w AS previous
+    FROM presence
+    WHERE account_id = $1 AND peer_id = $2
+      AND ts >= $3::timestamptz - interval '5 minutes' AND ts <= $4
+    WINDOW w AS (ORDER BY ts)
+),
+online AS (
+    SELECT greatest(ts, $3) AS started, ended,
+           count(*) FILTER (WHERE previous IS NULL
+                                OR ts > previous + interval '5 minutes')
+               OVER (ORDER BY ts) AS visit
+    FROM marks
+    WHERE status = 'online' AND ended > greatest(ts, $3)
+),
+sessions AS (
+    SELECT min(started) AS started, max(ended) AS ended,
+           extract(epoch FROM sum(ended - started))::float8 AS online_seconds
+    FROM online
+    GROUP BY visit
+)
+"""
+
+_SESSION_FIELDS = """
+started, ended, extract(epoch FROM ended - started)::float8 AS seconds,
+online_seconds, ended >= $4 AS ongoing
+"""
+
+_SESSION_PAGE = f"""
+WITH {_SESSIONS}
+SELECT {_SESSION_FIELDS}
+FROM sessions
+ORDER BY started DESC
+LIMIT $5 OFFSET $6
+"""  # noqa: S608
+
+_COVERED_HOURS = """
+    SELECT local_hour,
+           extract(epoch FROM sum(
+               least(ended, (local_hour + interval '1 hour') AT TIME ZONE $5)
+               - greatest(started, local_hour AT TIME ZONE $5)))::float8 AS seconds
+    FROM uptime,
+         generate_series(date_trunc('hour', started AT TIME ZONE $5),
+                         date_trunc('hour', ended AT TIME ZONE $5),
+                         interval '1 hour') AS local_hour
+    GROUP BY local_hour
+"""
+
+_STATS = f"""
+WITH {_SESSIONS},
+uptime AS (
+    SELECT greatest(started_at, $3) AS started,
+           least(seen_at + interval '90 seconds', $4) AS ended
+    FROM capture_uptime
+    WHERE account_id = $1 AND started_at < $4
+      AND seen_at + interval '90 seconds' > $3
+),
+quarters AS (
+    SELECT quarter, sum(ended - started - spill) AS inside, sum(spill) AS spill
+    FROM (SELECT started, ended, quarter,
+                 greatest(ended - quarter - interval '15 minutes',
+                          interval '0') AS spill
+          FROM (SELECT started, ended,
+                       date_bin('15 minutes', started, timestamptz 'epoch') AS quarter
+                FROM online) binned) split
+    GROUP BY quarter
+),
+online_hours AS (
+    SELECT date_trunc('hour', quarter AT TIME ZONE $5) AS local_hour,
+           extract(epoch FROM sum(share))::float8 AS seconds
+    FROM (SELECT quarter, inside AS share FROM quarters
+          UNION ALL
+          SELECT quarter + interval '15 minutes', spill FROM quarters) shares
+    GROUP BY 1
+),
+covered_hours AS ({_COVERED_HOURS}),
+hours AS (
+    SELECT local_hour,
+           extract(epoch FROM
+               least((local_hour + interval '1 hour') AT TIME ZONE $5, $4)
+               - greatest(local_hour AT TIME ZONE $5, $3))::float8 AS span,
+           coalesce(online.seconds, 0) AS online,
+           least(3600, greatest(coalesce(covered.seconds, 0),
+                                coalesce(online.seconds, 0))) AS covered
+    FROM generate_series(date_trunc('hour', $3 AT TIME ZONE $5),
+                         date_trunc('hour', $4 AT TIME ZONE $5),
+                         interval '1 hour') AS local_hour
+    LEFT JOIN online_hours AS online USING (local_hour)
+    LEFT JOIN covered_hours AS covered USING (local_hour)
+),
+week AS (
+    SELECT extract(isodow FROM local_hour)::int - 1 AS weekday,
+           extract(hour FROM local_hour)::int AS hour,
+           count(*) AS hours, sum(span) AS span,
+           sum(online) AS online, sum(covered) AS covered
+    FROM hours
+    GROUP BY 1, 2
+),
+days AS (
+    SELECT local_hour::date AS day, sum(online) AS online, sum(covered) AS covered
+    FROM hours
+    GROUP BY 1
+),
+uptime_reach AS (
+    SELECT started,
+           coalesce(max(ended) OVER (ORDER BY started
+                                     ROWS BETWEEN UNBOUNDED PRECEDING
+                                     AND 1 PRECEDING), $3) AS reached
+    FROM uptime
+),
+gaps AS (
+    SELECT reached AS started, started AS ended FROM uptime_reach
+    UNION ALL
+    SELECT coalesce(max(ended), $3), $4 FROM uptime
+),
+quiet AS (
+    SELECT hour
+    FROM week
+    GROUP BY hour
+    ORDER BY sum(online) / nullif(sum(covered), 0) NULLS LAST, hour
+    LIMIT 1
+),
+activity_days AS (
+    SELECT (sessions.started AT TIME ZONE $5) - make_interval(hours => quiet.hour)
+               AS started,
+           (sessions.ended AT TIME ZONE $5) - make_interval(hours => quiet.hour)
+               AS ended,
+           (($4 AT TIME ZONE $5) - make_interval(hours => quiet.hour))::date AS today
+    FROM sessions, quiet
+),
+daily AS (
+    SELECT extract(epoch FROM min(started - started::date))::float8 AS first_online,
+           extract(epoch FROM max(ended - started::date))::float8 AS last_offline
+    FROM activity_days
+    WHERE started::date < today
+    GROUP BY started::date
+)
+SELECT
+    (SELECT count(*) FROM sessions) AS session_count,
+    (SELECT coalesce(sum(online_seconds), 0) FROM sessions) AS online_seconds,
+    (SELECT sum(covered) FROM hours) AS covered_seconds,
+    (SELECT percentile_cont(0.5) WITHIN GROUP (
+         ORDER BY extract(epoch FROM ended - started)) FROM sessions) AS median_session,
+    (SELECT max(ended) FROM sessions) AS last_seen,
+    (SELECT hour FROM quiet) AS day_start,
+    (SELECT percentile_cont(0.5) WITHIN GROUP (ORDER BY first_online)
+     FROM daily) AS first_online,
+    (SELECT percentile_cont(0.5) WITHIN GROUP (ORDER BY last_offline)
+     FROM daily) AS last_offline,
+    (SELECT json_agg(json_build_object(
+         'weekday', weekday, 'hour', hour, 'hours', hours, 'span', span,
+         'online', online, 'covered', covered))
+     FROM week) AS week,
+    (SELECT json_agg(json_build_object(
+         'day', day, 'online_seconds', online, 'covered_seconds', covered)
+         ORDER BY day)
+     FROM days) AS days,
+    (SELECT json_agg(json_build_object('started', started, 'ended', ended)
+         ORDER BY started)
+     FROM gaps WHERE ended - started > interval '5 minutes') AS gaps,
+    (SELECT json_agg(row_to_json(page) ORDER BY page.started DESC)
+     FROM (SELECT {_SESSION_FIELDS} FROM sessions
+           ORDER BY started DESC LIMIT $6 OFFSET $7) page) AS sessions
+"""  # noqa: S608
+
+
+def _time_of_day(shifted: float | None, day_start: int | None) -> int | None:
+    if shifted is None or day_start is None:
+        return None
+    return round(shifted + day_start * SECONDS_IN_HOUR) % SECONDS_IN_DAY
+
+
+def _week(rows: list[dict]) -> list[PresenceHour]:
+    cells = {(row["weekday"], row["hour"]): row for row in rows}
+    week: list[PresenceHour] = []
+    for weekday in range(7):
+        for hour in range(24):
+            row = cells.get(
+                (weekday, hour), {"hours": 0, "span": 0, "online": 0, "covered": 0}
+            )
+            covered = row["covered"]
+            minutes = (
+                min(60.0, row["online"] / covered * 60)
+                if covered > 0
+                and covered >= min(MIN_CELL_COVERAGE, row["span"] * MIN_CELL_SHARE)
+                else None
+            )
+            week.append(
+                PresenceHour(
+                    weekday=weekday,
+                    hour=hour,
+                    hours=row["hours"],
+                    online_minutes=minutes,
+                    covered_hours=covered / SECONDS_IN_HOUR,
+                )
+            )
+    return week
+
+
+async def presence_stats(  # noqa: PLR0913
+    pool: asyncpg.Pool, account_id: int, peer_id: int, page: Page, *, days: int, tz: str
+) -> PresenceStats:
+    since, until = await period_bounds(pool, days, tz)
+    async with pool.acquire() as conn, conn.transaction():
+        await conn.execute(f"SET LOCAL work_mem = '{STATS_WORK_MEM}'")
+        row = await conn.fetchrow(
+            _STATS,
+            account_id,
+            peer_id,
+            since,
+            until,
+            tz,
+            page.capped_limit,
+            page.offset,
+        )
+    current = await current_presence(pool, account_id, peer_id)
+    sessions = [PresenceSession(**item) for item in json.loads(row["sessions"] or "[]")]
+    covered = row["covered_seconds"] or 0
+    online = row["online_seconds"]
+    return PresenceStats(
+        peer_id=peer_id,
+        tz=tz,
+        since=since,
+        until=until,
+        current=current,
+        online=current is not None
+        and current.status == "online"
+        and current.next_offline_date is not None
+        and current.next_offline_date > until,
+        hidden=row["session_count"] == 0
+        and current is not None
+        and current.status in FUZZY_STATUSES,
+        summary=PresenceSummary(
+            online_seconds=online,
+            daily_seconds=online / covered * SECONDS_IN_DAY
+            if covered >= SECONDS_IN_HOUR
+            else None,
+            covered_seconds=covered,
+            session_count=row["session_count"],
+            median_session_seconds=row["median_session"],
+            first_online=_time_of_day(row["first_online"], row["day_start"]),
+            last_offline=_time_of_day(row["last_offline"], row["day_start"]),
+            last_seen=row["last_seen"]
+            or (current.last_online_date if current else None),
+        ),
+        week=_week(json.loads(row["week"] or "[]")),
+        days=[PresenceDay(**item) for item in json.loads(row["days"] or "[]")],
+        gaps=[CoverageGap(**item) for item in json.loads(row["gaps"] or "[]")],
+        sessions=sessions,
+    )
+
+
+async def presence_sessions(  # noqa: PLR0913
+    pool: asyncpg.Pool, account_id: int, peer_id: int, page: Page, *, days: int, tz: str
+) -> list[PresenceSession]:
+    since, until = await period_bounds(pool, days, tz)
+    rows = await pool.fetch(
+        _SESSION_PAGE, account_id, peer_id, since, until, page.capped_limit, page.offset
+    )
+    return [PresenceSession(**dict(row)) for row in rows]

backend/src/utils/read/read_receipts.py

@@ -1,5 +1,89 @@
+from datetime import UTC, datetime, timedelta
+
 import asyncpg
 
+from utils.policy.models import ChatKind
+from utils.read.discover import chat_kind
+from utils.read.models import ReaderView, ReadInfoView
+from utils.read.peers import get_peers
+
+FETCH_WINDOW = timedelta(days=7)
+CLOCK_SKEW = timedelta(minutes=1)
+VOICE_KINDS = ["voice", "video_note"]
+
+_READ_TIMES = """
+SELECT m.id,
+    COALESCE(
+        (SELECT min(mr.read_at) FROM message_reads mr
+         WHERE mr.account_id = $1 AND mr.chat_id = $2 AND mr.message_id = m.id),
+        CASE WHEN m.date >= $5 THEN (
+            SELECT r.ts FROM read_receipts r
+            WHERE r.account_id = $1 AND r.chat_id = $2 AND r.kind = 'read'
+              AND r.message_id >= m.id AND r.ts >= m.date - $6::interval
+            ORDER BY r.ts LIMIT 1
+        ) END
+    ) AS read_at
+FROM unnest($3::bigint[], $4::timestamptz[]) AS m(id, date)
+"""
+
+_MESSAGE = """
+SELECT m.sender_id, m.date, a.tg_user_id, a.is_bot,
+    EXISTS (
+        SELECT 1 FROM media md
+        WHERE md.account_id = m.account_id AND md.chat_id = m.chat_id
+          AND md.message_id = m.message_id AND md.kind = ANY($4::text[])
+    ) AS voice
+FROM messages m
+JOIN accounts a ON a.account_id = m.account_id
+WHERE m.account_id = $1 AND m.chat_id = $2 AND m.message_id = $3
+LIMIT 1
+"""
+
+_RECEIPTS = """
+SELECT
+    (SELECT ts FROM read_receipts
+     WHERE account_id = $1 AND chat_id = $2 AND kind = 'read'
+       AND message_id >= $3 AND ts >= $4
+     ORDER BY ts LIMIT 1) AS observed_at,
+    (SELECT min(ts) FROM read_receipts
+     WHERE account_id = $1 AND chat_id = $2 AND kind = 'listened'
+       AND message_id = $3) AS listened_at,
+    (SELECT max(message_id) FROM read_receipts
+     WHERE account_id = $1 AND chat_id = $2 AND kind = 'read') AS watermark
+"""
+
+_READS = """
+SELECT reader_id, read_at, source FROM message_reads
+WHERE account_id = $1 AND chat_id = $2 AND message_id = $3
+ORDER BY read_at
+"""
+
+_FETCH = """
+SELECT outcome, fetched_at, retry_at FROM read_fetches
+WHERE account_id = $1 AND chat_id = $2 AND message_id = $3
+"""
+
+_INHERITED = """
+SELECT outcome FROM read_fetches
+WHERE account_id = $1 AND retry_at > now()
+  AND ((chat_id = $2 AND outcome = 'chat_too_big') OR outcome = 'your_privacy')
+LIMIT 1
+"""
+
+_capture_starts: dict[int, datetime] = {}
+
+
+async def capture_start(pool: asyncpg.Pool, account_id: int) -> datetime | None:
+    cached = _capture_starts.get(account_id)
+    if cached is not None:
+        return cached
+    start = await pool.fetchval(
+        "SELECT min(ts) FROM read_receipts WHERE account_id = $1", account_id
+    )
+    if start is not None:
+        _capture_starts[account_id] = start
+    return start
+
 
 async def read_up_to(pool: asyncpg.Pool, account_id: int, chat_id: int) -> int | None:
     return await pool.fetchval(
@@ -8,3 +92,97 @@ async def read_up_to(pool: asyncpg.Pool, account_id: int, chat_id: int) -> int |
         account_id,
         chat_id,
     )
+
+
+async def read_times(
+    pool: asyncpg.Pool,
+    account_id: int,
+    chat_id: int,
+    messages: list[tuple[int, datetime]],
+) -> dict[int, datetime]:
+    if not messages:
+        return {}
+    start = await capture_start(pool, account_id) or datetime.max.replace(tzinfo=UTC)
+    rows = await pool.fetch(
+        _READ_TIMES,
+        account_id,
+        chat_id,
+        [message_id for message_id, _ in messages],
+        [date for _, date in messages],
+        start,
+        CLOCK_SKEW,
+    )
+    return {row["id"]: row["read_at"] for row in rows if row["read_at"] is not None}
+
+
+async def read_info(
+    pool: asyncpg.Pool, account_id: int, chat_id: int, message_id: int
+) -> ReadInfoView | None:
+    message = await pool.fetchrow(
+        _MESSAGE, account_id, chat_id, message_id, VOICE_KINDS
+    )
+    if message is None:
+        return None
+    kind = await chat_kind(pool, account_id, chat_id)
+    date: datetime = message["date"]
+    receipts = await pool.fetchrow(
+        _RECEIPTS, account_id, chat_id, message_id, date - CLOCK_SKEW
+    )
+    reads = await pool.fetch(_READS, account_id, chat_id, message_id)
+    fetch = await pool.fetchrow(_FETCH, account_id, chat_id, message_id)
+    inherited = await pool.fetchval(_INHERITED, account_id, chat_id)
+    start = await capture_start(pool, account_id)
+
+    observed_at = receipts["observed_at"] if start and date >= start else None
+    exact_at = next(
+        (row["read_at"] for row in reads if row["source"] == "outbox_date"), None
+    )
+    reader_rows = [row for row in reads if row["source"] == "participants"]
+    known = {
+        peer.peer_id: peer
+        for peer in await get_peers(
+            pool, account_id, [row["reader_id"] for row in reader_rows]
+        )
+    }
+    readers = [
+        ReaderView(
+            peer_id=row["reader_id"],
+            read_at=row["read_at"],
+            peer=known.get(row["reader_id"]),
+        )
+        for row in reader_rows
+    ]
+    outcome = fetch["outcome"] if fetch else inherited
+
+    now = datetime.now(UTC)
+    own = (
+        message["sender_id"] is not None
+        and message["sender_id"] == (message["tg_user_id"])
+    )
+    applicable = own and kind != ChatKind.CHANNEL and chat_id != message["tg_user_id"]
+    watermark = receipts["watermark"]
+    covered = watermark is not None and message_id <= watermark
+    seen = covered or any((exact_at, readers, receipts["listened_at"]))
+    evidence = watermark is not None or outcome in {"ok", "not_read_yet"}
+    due = fetch is None or fetch["retry_at"] <= now
+    return ReadInfoView(
+        chat_id=chat_id,
+        message_id=message_id,
+        chat_kind=kind.value,
+        own=own,
+        voice=message["voice"],
+        observed_at=observed_at,
+        listened_at=receipts["listened_at"],
+        exact_at=exact_at,
+        readers=readers,
+        read=applicable and seen,
+        unread=applicable and not seen and evidence,
+        outcome=outcome,
+        fetched_at=fetch["fetched_at"] if fetch else None,
+        can_fetch=applicable
+        and not message["is_bot"]
+        and now - date < FETCH_WINDOW
+        and exact_at is None
+        and inherited is None
+        and due,
+    )

frontend/src/lib/api/endpoints.ts

@@ -28,9 +28,11 @@ import type {
   PolicyRecord,
   PolicyRule,
   PolicyScope,
-  PresenceHourly,
   PresenceSample,
+  PresenceSession,
+  PresenceStats,
   ReactionView,
+  ReadInfo,
   ResponseStats,
   ScopeTarget,
   SearchHit,
@@ -205,30 +207,38 @@ export function getCurrentPresence(
   });
 }
 
-export function getPresenceHistory(
+export function getPresenceStats(
   peerId: number,
+  days: number,
+  tz: string,
   page: Page = {}
-): Promise<PresenceSample[]> {
-  return request<PresenceSample[]>("/presence", {
+): Promise<PresenceStats> {
+  return request<PresenceStats>("/presence/stats", {
     account: true,
-    query: { peer_id: peerId, ...page },
+    query: { days, peer_id: peerId, tz, ...page },
   });
 }
 
-export function getPresenceHourly(peerId: number): Promise<PresenceHourly[]> {
-  return request<PresenceHourly[]>("/presence/hourly", {
+export function getPresenceSessions(
+  peerId: number,
+  days: number,
+  tz: string,
+  page: Page = {}
+): Promise<PresenceSession[]> {
+  return request<PresenceSession[]>("/presence/sessions", {
     account: true,
-    query: { peer_id: peerId },
+    query: { days, peer_id: peerId, tz, ...page },
   });
 }
 
 export function getMessageVolume(
   chatId: number,
-  days = 90
+  days: number,
+  tz: string
 ): Promise<VolumeBucket[]> {
   return request<VolumeBucket[]>("/analytics/volume", {
     account: true,
-    query: { chat_id: chatId, days },
+    query: { chat_id: chatId, days, tz },
   });
 }
 
@@ -304,6 +314,25 @@ export function getChatLinks(
   });
 }
 
+export function getReadInfo(
+  chatId: number,
+  messageId: number
+): Promise<ReadInfo> {
+  return request<ReadInfo>(`/messages/${chatId}/${messageId}/read`, {
+    account: true,
+  });
+}
+
+export function refreshReadInfo(
+  chatId: number,
+  messageId: number
+): Promise<{ job_id: number | null }> {
+  return request<{ job_id: number | null }>(
+    `/messages/${chatId}/${messageId}/read/refresh`,
+    { body: { account_id: accounts.selectedId }, method: "POST" }
+  );
+}
+
 export function getMessageReactions(
   chatId: number,
   messageId: number

frontend/src/lib/api/types.ts

@@ -204,6 +204,7 @@ export interface MessageView {
   quote: string | null;
   reactions: ReactionCount[];
   read: boolean;
+  read_at: string | null;
   reply: ReplyView | null;
   sender_id: number | null;
   service: ServiceView | null;
@@ -335,12 +336,57 @@ export interface PresenceSample {
   ts: string;
 }
 
-export interface PresenceHourly {
-  bucket: string;
+export interface PresenceSession {
+  ended: string;
+  ongoing: boolean;
+  online_seconds: number;
+  seconds: number;
+  started: string;
+}
+
+export interface PresenceHour {
+  covered_hours: number;
+  hour: number;
+  hours: number;
+  online_minutes: number | null;
+  weekday: number;
+}
+
+export interface PresenceDay {
+  covered_seconds: number;
+  day: string;
+  online_seconds: number;
+}
+
+export interface CoverageGap {
+  ended: string;
+  started: string;
+}
+
+export interface PresenceSummary {
+  covered_seconds: number;
+  daily_seconds: number | null;
+  first_online: number | null;
+  last_offline: number | null;
   last_seen: string | null;
-  online_samples: number;
+  median_session_seconds: number | null;
+  online_seconds: number;
+  session_count: number;
+}
+
+export interface PresenceStats {
+  current: PresenceSample | null;
+  days: PresenceDay[];
+  gaps: CoverageGap[];
+  hidden: boolean;
+  online: boolean;
   peer_id: number;
-  samples: number;
+  sessions: PresenceSession[];
+  since: string;
+  summary: PresenceSummary;
+  tz: string;
+  until: string;
+  week: PresenceHour[];
 }
 
 export interface VolumeBucket {
@@ -369,6 +415,40 @@ export interface PeerView {
   username: string | null;
 }
 
+export interface ReaderView {
+  peer: PeerView | null;
+  peer_id: number;
+  read_at: string;
+}
+
+export type ReadOutcome =
+  | "ok"
+  | "not_read_yet"
+  | "user_privacy"
+  | "your_privacy"
+  | "chat_too_big"
+  | "too_old"
+  | "unavailable"
+  | "flood"
+  | "error";
+
+export interface ReadInfo {
+  can_fetch: boolean;
+  chat_id: number;
+  chat_kind: "dm" | "group" | "channel";
+  exact_at: string | null;
+  fetched_at: string | null;
+  listened_at: string | null;
+  message_id: number;
+  observed_at: string | null;
+  outcome: ReadOutcome | null;
+  own: boolean;
+  read: boolean;
+  readers: ReaderView[];
+  unread: boolean;
+  voice: boolean;
+}
+
 export interface PeerHistoryView {
   first_name: string | null;
   is_deleted_account: boolean;
@@ -518,6 +598,7 @@ export interface LivePresenceEvent {
 
 export interface LiveReceiptEvent {
   chat_id: number;
+  read_at: string;
   read_up_to: number;
   type: "receipt";
 }

frontend/src/lib/components/ChatHeader.svelte

@@ -1,10 +1,6 @@
 <script lang="ts">
-  import {
-    enqueueBackfill,
-    getCurrentPresence,
-    getPeer,
-  } from "#lib/api/endpoints.js";
-  import type { PeerView, PresenceSample } from "#lib/api/types.js";
+  import { enqueueBackfill, getPeer } from "#lib/api/endpoints.js";
+  import type { PeerView } from "#lib/api/types.js";
   import Avatar from "#lib/components/ui/Avatar.svelte";
   import Button from "#lib/components/ui/Button.svelte";
   import ContextMenu from "#lib/components/ui/ContextMenu.svelte";
@@ -16,6 +12,7 @@
   import { chats } from "#lib/stores/chats.svelte.js";
   import { discover } from "#lib/stores/discover.svelte.js";
   import { policyUi } from "#lib/stores/policy.svelte.js";
+  import { presence } from "#lib/stores/presence.svelte.js";
   import { toasts } from "#lib/stores/toasts.svelte.js";
   import { ui } from "#lib/stores/ui.svelte.js";
   import { goto } from "$app/navigation";
@@ -26,13 +23,10 @@
 
   let { chatId }: Props = $props();
 
-  const PRESENCE_INTERVAL = 30_000;
-
   const isDm = $derived(chatId > 0);
   const chat = $derived(chats.byId(chatId));
   const discovered = $derived(discover.get(chatId));
   let peer = $state<PeerView | null>(null);
-  let presence = $state<PresenceSample | null>(null);
   let backfilling = $state(false);
 
   async function backfill() {
@@ -81,34 +75,8 @@
   });
 
   $effect(() => {
-    if (accounts.selectedId === null || !isDm) {
-      presence = null;
-      return;
-    }
-    let active = true;
-    presence = null;
-    const refresh = () => {
-      if (document.visibilityState !== "visible") {
-        return;
-      }
-      getCurrentPresence(chatId)
-        .then((result) => {
-          if (active) {
-            presence = result;
-          }
-        })
-        .catch(() => {
-          if (active) {
-            presence = null;
-          }
-        });
-    };
-    refresh();
-    const timer = setInterval(refresh, PRESENCE_INTERVAL);
-    return () => {
-      active = false;
-      clearInterval(timer);
-    };
+    presence.follow(accounts.selectedId, isDm ? chatId : null);
+    return () => presence.follow(null, null);
   });
 
   const fallbackTitle = $derived(
@@ -119,8 +87,8 @@
   const title = $derived(isDm && peer ? peerName(peer) : fallbackTitle);
   const subtitle = $derived.by(() => {
     if (isDm) {
-      if (presence) {
-        return formatPresence(presence);
+      if (presence.sample) {
+        return formatPresence(presence.sample, presence.now);
       }
       if (peer?.username) {
         return `@${peer.username}`;
@@ -176,7 +144,12 @@
         />
         <div class="info">
           <h2 class="title">{title}</h2>
-          <span class="subtitle" class:online={isDm && isOnline(presence)}>
+          <span
+            class={[
+              "subtitle",
+              { online: isDm && isOnline(presence.sample, presence.now) },
+            ]}
+          >
             {subtitle}
           </span>
         </div>

frontend/src/lib/components/MessageBubble.svelte

@@ -11,6 +11,7 @@
   import Poll from "#lib/components/Poll.svelte";
   import Reactions from "#lib/components/Reactions.svelte";
   import ReplyHeader from "#lib/components/ReplyHeader.svelte";
+  import MessageReadItem from "#lib/components/read/MessageReadItem.svelte";
   import Avatar from "#lib/components/ui/Avatar.svelte";
   import ContextMenu from "#lib/components/ui/ContextMenu.svelte";
   import ContextMenuItem from "#lib/components/ui/ContextMenuItem.svelte";
@@ -247,6 +248,9 @@
     </div>
   {/snippet}
   {#snippet menu()}
+    {#if own}
+      <MessageReadItem {message} />
+    {/if}
     <ContextMenuItem icon="note" onselect={openAnnotations}
       >Заметки</ContextMenuItem
     >

frontend/src/lib/components/MessageList.svelte

@@ -363,13 +363,13 @@
     );
   }
 
-  function applyReceipt(readUpTo: number) {
+  function applyReceipt(readUpTo: number, readAt: string) {
     if (ownId === null) {
       return;
     }
     messages = messages.map((m) =>
       m.sender_id === ownId && m.message_id <= readUpTo && !m.read
-        ? { ...m, read: true }
+        ? { ...m, read: true, read_at: readAt }
         : m
     );
   }
@@ -388,7 +388,7 @@
     ) {
       applyDelete(event.message_ids);
     } else if (event.type === "receipt" && event.chat_id === chatId) {
-      applyReceipt(event.read_up_to);
+      applyReceipt(event.read_up_to, event.read_at);
     }
   }
 

frontend/src/lib/components/MessageMedia.svelte

@@ -14,6 +14,7 @@
   import TgsSticker from "#lib/components/media/TgsSticker.svelte";
   import VideoNote from "#lib/components/media/VideoNote.svelte";
   import VoiceMessage from "#lib/components/media/VoiceMessage.svelte";
+  import MessageReadItem from "#lib/components/read/MessageReadItem.svelte";
   import ContextMenu from "#lib/components/ui/ContextMenu.svelte";
   import ContextMenuItem from "#lib/components/ui/ContextMenuItem.svelte";
   import Icon from "#lib/components/ui/Icon.svelte";
@@ -222,6 +223,9 @@
     </div>
   {/snippet}
   {#snippet menu()}
+    {#if own}
+      <MessageReadItem {message} />
+    {/if}
     <ContextMenuItem icon="open-in-new-tab" onselect={onopen}
       >Открыть на весь экран</ContextMenuItem
     >

frontend/src/lib/components/MessageMeta.svelte

@@ -2,6 +2,7 @@
   import type { MessageView } from "#lib/api/types.js";
   import Icon from "#lib/components/ui/Icon.svelte";
   import { formatTime } from "#lib/format/datetime.js";
+  import { readTitle } from "#lib/format/read.js";
 
   interface Props {
     message: MessageView;
@@ -25,11 +26,9 @@
   {/if}
   <span class="time">{formatTime(message.date)}</span>
   {#if own}
-    <Icon
-      class="ticks"
-      name={message.read ? "message-read" : "check"}
-      size="1rem"
-    />
+    <span class="ticks" title={readTitle(message)}>
+      <Icon name={message.read ? "message-read" : "check"} size="1rem" />
+    </span>
   {/if}
 </span>
 
@@ -52,6 +51,10 @@
     white-space: nowrap;
   }
 
+  .ticks {
+    display: inline-flex;
+  }
+
   .edited {
     cursor: pointer;
     padding: 0;

frontend/src/lib/components/RightColumn.svelte

@@ -8,6 +8,7 @@
   import PolicyEditor from "#lib/components/policy/PolicyEditor.svelte";
   import AnalyticsPanel from "#lib/components/presence/AnalyticsPanel.svelte";
   import ProfilePanel from "#lib/components/profile/ProfilePanel.svelte";
+  import ReadersPanel from "#lib/components/read/ReadersPanel.svelte";
   import ChatSearchPanel from "#lib/components/search/ChatSearchPanel.svelte";
   import SharesPanel from "#lib/components/shares/SharesPanel.svelte";
   import CallbacksPanel from "#lib/components/social/CallbacksPanel.svelte";
@@ -18,13 +19,14 @@
   import Button from "#lib/components/ui/Button.svelte";
   import Icon from "#lib/components/ui/Icon.svelte";
   import WatchesPanel from "#lib/components/watches/WatchesPanel.svelte";
+  import { t } from "#lib/i18n/locale.svelte.js";
   import { accounts } from "#lib/stores/accounts.svelte.js";
   import { chats } from "#lib/stores/chats.svelte.js";
   import { policyUi } from "#lib/stores/policy.svelte.js";
   import { storageUi } from "#lib/stores/storage.svelte.js";
   import { type RightPanel, ui } from "#lib/stores/ui.svelte.js";
 
-  const titles: Record<RightPanel, string> = {
+  const titles: Record<RightPanel, string> = $derived({
     alerts: "Алерты",
     annotations: "Заметки",
     bots: "Боты",
@@ -35,6 +37,7 @@
     presence: "Аналитика",
     profile: "Профиль",
     reactions: "Реакции",
+    readers: t("read.readers.title"),
     search: "Поиск",
     shares: "Файлы по ссылке",
     storage: "Хранилище",
@@ -44,7 +47,7 @@
     "stories-all": "Все сторис",
     versions: "Версии",
     watches: "Отслеживания",
-  };
+  });
 
   const parents: Partial<Record<RightPanel, RightPanel>> = {
     "storage-chat": "storage",
@@ -104,6 +107,8 @@
     <ChatSearchPanel />
   {:else if ui.rightPanel === "reactions"}
     <ReactionsPanel />
+  {:else if ui.rightPanel === "readers"}
+    <ReadersPanel />
   {:else if ui.rightPanel === "callbacks"}
     <CallbacksPanel />
   {:else if ui.rightPanel === "links"}

frontend/src/lib/components/presence/AnalyticsPanel.svelte

@@ -1,193 +1,295 @@
 <script lang="ts">
   import {
-    getCurrentPresence,
     getMessageVolume,
-    getPresenceHistory,
-    getPresenceHourly,
+    getPresenceStats,
     getResponseStats,
   } from "#lib/api/endpoints.js";
   import type {
-    PresenceHourly,
-    PresenceSample,
+    PresenceStats,
     ResponseStats,
     VolumeBucket,
   } from "#lib/api/types.js";
+  import OnlineDays from "#lib/components/presence/OnlineDays.svelte";
   import PresenceHeatmap from "#lib/components/presence/PresenceHeatmap.svelte";
+  import PresenceSessions from "#lib/components/presence/PresenceSessions.svelte";
   import VolumeChart from "#lib/components/presence/VolumeChart.svelte";
+  import Button from "#lib/components/ui/Button.svelte";
   import EmptyState from "#lib/components/ui/EmptyState.svelte";
-  import { formatFull } from "#lib/format/datetime.js";
-  import { formatPresence } from "#lib/format/presence.js";
+  import Spinner from "#lib/components/ui/Spinner.svelte";
+  import { browserTimeZone, timeZoneLabel } from "#lib/format/datetime.js";
+  import {
+    formatClock,
+    formatLongSpan,
+    formatPresence,
+    formatSpan,
+    isOnline,
+  } from "#lib/format/presence.js";
   import { accounts } from "#lib/stores/accounts.svelte.js";
-  import { events } from "#lib/stores/events.svelte.js";
+  import { presence } from "#lib/stores/presence.svelte.js";
   import { page } from "$app/state";
 
-  const HISTORY_LIMIT = 200;
-  const SECONDS_IN_MINUTE = 60;
+  const TEXT = {
+    average: "В среднем за день",
+    byDay: "По дням",
+    byHour: "По часам недели",
+    failed: "Не удалось загрузить аналитику.",
+    firstOnline: "Обычно появляется",
+    hidden:
+      "Скрывает, когда был(а) в сети. Telegram показывает только «был(а) недавно», поэтому время в сети не посчитать.",
+    lastOffline: "Обычно уходит",
+    median: "Обычная сессия",
+    messages: "Сообщения",
+    mine: "Я отвечаю",
+    missing: "Нет данных",
+    noData: "нет данных",
+    noMessages: "За этот период сообщений нет.",
+    noStatus: "Статусов пока нет.",
+    openChat: "Откройте чат",
+    period: (count: number) => `${count} дней`,
+    retry: "Повторить",
+    sessions: "Сессии",
+    theirs: "Мне отвечают",
+    title: "Аналитика",
+    total: (count: number) => `в сети за ${count} дней`,
+  };
+
+  const PERIODS = [7, 30, 90];
+  const DEFAULT_PERIOD = 30;
+  const SESSION_PAGE = 30;
   const SECONDS_IN_HOUR = 3600;
-  const SECONDS_IN_DAY = 86_400;
+  const MS_IN_SECOND = 1000;
+
+  const tz = browserTimeZone();
+  const zone = timeZoneLabel();
 
   const chatId = $derived(
     page.params.chatId ? Number(page.params.chatId) : null
   );
   const isDm = $derived(chatId !== null && chatId > 0);
 
-  let current = $state<PresenceSample | null>(null);
-  let hourly = $state<PresenceHourly[]>([]);
-  let history = $state<PresenceSample[]>([]);
-  let volume = $state<VolumeBucket[]>([]);
+  let days = $state(DEFAULT_PERIOD);
+  let stats = $state<PresenceStats | null>(null);
+  let volume = $state<VolumeBucket[] | null>(null);
   let response = $state<ResponseStats | null>(null);
-  let loading = $state(false);
+  let shownDays = $state(DEFAULT_PERIOD);
+  let failed = $state(false);
+  let shownChat: number | null = null;
+  let token = 0;
 
-  const changes = $derived.by(() => {
-    const result: PresenceSample[] = [];
-    let last: string | null = null;
-    for (const sample of history) {
-      if (sample.status !== last) {
-        result.push(sample);
-        last = sample.status;
+  const sample = $derived(
+    presence.sample?.peer_id === chatId
+      ? presence.sample
+      : (stats?.current ?? null)
+  );
+  const online = $derived(isOnline(sample, presence.now));
+  const tracked = $derived(
+    stats !== null &&
+      (stats.current !== null || stats.summary.session_count > 0)
+  );
+  const quiet = $derived(
+    volume?.every((bucket) => bucket.total === 0) ?? false
+  );
+  const rows = $derived.by(() => {
+    if (stats === null) {
+      return [];
     }
+    const { summary } = stats;
+    const result: { label: string; value: string }[] = [];
+    if (summary.daily_seconds !== null) {
+      result.push({
+        label: TEXT.average,
+        value: formatSpan(summary.daily_seconds),
+      });
+    }
+    if (summary.median_session_seconds !== null) {
+      result.push({
+        label: TEXT.median,
+        value: formatSpan(summary.median_session_seconds),
+      });
+    }
+    if (summary.first_online !== null) {
+      result.push({
+        label: TEXT.firstOnline,
+        value: formatClock(summary.first_online),
+      });
+    }
+    if (summary.last_offline !== null) {
+      result.push({
+        label: TEXT.lastOffline,
+        value: formatClock(summary.last_offline),
+      });
+    }
+    const period =
+      (new Date(stats.until).getTime() - new Date(stats.since).getTime()) /
+      MS_IN_SECOND;
+    const missing = period - summary.covered_seconds;
+    if (missing >= SECONDS_IN_HOUR) {
+      result.push({ label: TEXT.missing, value: formatLongSpan(missing) });
     }
     return result;
   });
 
-  function formatDuration(seconds: number | null): string {
-    if (seconds === null) {
-      return "—";
+  function reply(seconds: number | null): string {
+    return seconds === null ? TEXT.noData : formatSpan(seconds);
   }
-    if (seconds < SECONDS_IN_MINUTE) {
-      return `${Math.round(seconds)} с`;
+
+  async function load(id: number, period: number) {
+    token += 1;
+    const current = token;
+    failed = false;
+    if (shownChat !== id) {
+      shownChat = id;
+      stats = null;
+      volume = null;
+      response = null;
     }
-    if (seconds < SECONDS_IN_HOUR) {
-      return `${Math.round(seconds / SECONDS_IN_MINUTE)} мин`;
+    try {
+      const [nextStats, nextVolume, nextResponse] = await Promise.all([
+        id > 0
+          ? getPresenceStats(id, period, tz, { limit: SESSION_PAGE })
+          : Promise.resolve(null),
+        getMessageVolume(id, period, tz),
+        getResponseStats(id),
+      ]);
+      if (current === token) {
+        stats = nextStats;
+        volume = nextVolume;
+        response = nextResponse;
+        shownDays = period;
+      }
+    } catch {
+      if (current === token) {
+        failed = true;
       }
-    if (seconds < SECONDS_IN_DAY) {
-      return `${Math.round(seconds / SECONDS_IN_HOUR)} ч`;
     }
-    return `${Math.round(seconds / SECONDS_IN_DAY)} д`;
   }
 
   $effect(() => {
-    if (accounts.selectedId === null || chatId === null) {
-      return;
+    if (accounts.selectedId !== null && chatId !== null) {
+      load(chatId, days);
     }
-    const id = chatId;
-    let active = true;
-    loading = true;
-    current = null;
-    hourly = [];
-    history = [];
-    volume = [];
-    response = null;
-    Promise.all([getMessageVolume(id), getResponseStats(id)])
-      .then(([vol, resp]) => {
-        if (active) {
-          volume = vol;
-          response = resp;
-        }
-      })
-      .catch(() => undefined)
-      .finally(() => {
-        if (active) {
-          loading = false;
-        }
-      });
-    if (id > 0) {
-      Promise.all([
-        getCurrentPresence(id),
-        getPresenceHourly(id),
-        getPresenceHistory(id, { limit: HISTORY_LIMIT }),
-      ])
-        .then(([cur, hrs, hist]) => {
-          if (active) {
-            current = cur;
-            hourly = hrs;
-            history = hist;
-          }
-        })
-        .catch(() => undefined);
-    }
-    const unsub = events.subscribe((event) => {
-      if (event.type === "presence" && event.peer_id === id && event.sample) {
-        current = event.sample;
-      }
-    });
-    return () => {
-      active = false;
-      unsub();
-    };
   });
 </script>
 
 {#if chatId === null}
-  <EmptyState description="Откройте чат" title="Аналитика" />
+  <EmptyState description={TEXT.openChat} title={TEXT.title} />
 {:else}
   <div class="analytics">
+    <div class="periods">
+      {#each PERIODS as period (period)}
+        <button
+          aria-pressed={days === period}
+          class={["period", { on: days === period }]}
+          onclick={() => {
+            days = period;
+          }}
+          type="button"
+        >
+          {TEXT.period(period)}
+        </button>
+      {/each}
+    </div>
+
+    {#if failed}
+      <div class="state">
+        <p>{TEXT.failed}</p>
+        <Button
+          onclick={() => chatId !== null && load(chatId, days)}
+          smaller
+          variant="text"
+        >
+          {TEXT.retry}
+        </Button>
+      </div>
+    {:else if volume === null || (isDm && stats === null)}
+      <div class="state"><Spinner /></div>
+    {:else}
+      {#if isDm && stats}
+        <section class="hero">
+          {#if tracked && !stats.hidden}
+            <div class="total-line">
+              <span class="total"
+                >{formatSpan(stats.summary.online_seconds)}</span
+              >
+              <span class="count">{TEXT.total(shownDays)}</span>
+            </div>
+          {/if}
+          {#if sample}
+            <p class={["status", { online }]}>
+              {formatPresence(sample, presence.now)}
+            </p>
+          {/if}
+          {#if stats.hidden}
+            <p class="note">{TEXT.hidden}</p>
+          {:else if !tracked}
+            <p class="note">{TEXT.noStatus}</p>
+          {/if}
+        </section>
+
+        {#if tracked && !stats.hidden}
+          {#if rows.length > 0}
             <section>
-      <h3>Объём сообщений (90 дней)</h3>
-      {#if volume.length === 0}
-        <p class="muted">{loading ? "Загрузка…" : "Нет сообщений"}</p>
+              <dl class="rows">
+                {#each rows as row (row.label)}
+                  <div class="row">
+                    <dt>{row.label}</dt>
+                    <dd>{row.value}</dd>
+                  </div>
+                {/each}
+              </dl>
+            </section>
+          {/if}
+
+          <section>
+            <div class="section-title">
+              <h3>{TEXT.byHour}</h3>
+              <span>{zone}</span>
+            </div>
+            <PresenceHeatmap week={stats.week} />
+          </section>
+
+          <section>
+            <div class="section-title"><h3>{TEXT.byDay}</h3></div>
+            <OnlineDays days={stats.days} />
+          </section>
+        {/if}
+      {/if}
+
+      <section>
+        <div class="section-title"><h3>{TEXT.messages}</h3></div>
+        {#if quiet}
+          <p class="state">{TEXT.noMessages}</p>
         {:else}
           <VolumeChart {volume} />
         {/if}
-    </section>
-
-    <section>
-      <h3>Время ответа</h3>
-      {#if response}
-        <div class="stats">
-          <div class="stat">
-            <span class="value"
-              >{formatDuration(response.mine_median_seconds)}</span
-            >
-            <span class="caption">я отвечаю ({response.mine_count})</span>
+        {#if response && response.mine_count + response.their_count > 0}
+          <dl class="rows replies">
+            <div class="row">
+              <dt>{TEXT.mine}</dt>
+              <dd>{reply(response.mine_median_seconds)}</dd>
             </div>
-          <div class="stat">
-            <span class="value"
-              >{formatDuration(response.their_median_seconds)}</span
-            >
-            <span class="caption">мне отвечают ({response.their_count})</span>
+            <div class="row">
+              <dt>{TEXT.theirs}</dt>
+              <dd>{reply(response.their_median_seconds)}</dd>
             </div>
-        </div>
-      {:else}
-        <p class="muted">{loading ? "Загрузка…" : "Нет данных"}</p>
+          </dl>
         {/if}
       </section>
 
-    {#if isDm}
+      {#if isDm && stats && tracked && !stats.hidden}
         <section>
-        <div class="status" class:online={current?.status === "online"}>
-          {current ? formatPresence(current) : "нет данных"}
-        </div>
+          <div class="section-title"><h3>{TEXT.sessions}</h3></div>
+          {#key `${chatId}:${shownDays}:${stats.until}`}
+            <PresenceSessions
+              days={shownDays}
+              first={stats.sessions}
+              pageSize={SESSION_PAGE}
+              peerId={stats.peer_id}
+              {tz}
+            />
+          {/key}
         </section>
-
-      <section>
-        <h3>Когда в сети</h3>
-        {#if hourly.length === 0}
-          <p class="muted">{loading ? "Загрузка…" : "Пока нет данных"}</p>
-        {:else}
-          <PresenceHeatmap {hourly} />
       {/if}
-      </section>
-
-      <section>
-        <h3>История статусов</h3>
-        {#if changes.length === 0}
-          <p class="muted">{loading ? "Загрузка…" : "Нет записей"}</p>
-        {:else}
-          <ul class="changes">
-            {#each changes as sample (sample.ts)}
-              <li>
-                <span
-                  class="dot"
-                  class:online={sample.status === "online"}
-                ></span>
-                <span class="label">{formatPresence(sample)}</span>
-                <span class="time">{formatFull(sample.ts)}</span>
-              </li>
-            {/each}
-          </ul>
-        {/if}
-      </section>
     {/if}
   </div>
 {/if}
@@ -196,48 +298,89 @@
   .analytics {
     display: flex;
     flex-direction: column;
-    gap: 1.5rem;
-    padding: 1rem;
+    padding-bottom: 0.5rem;
+  }
+
+  .periods {
+    display: flex;
+    gap: 0.25rem;
+
+    margin: 0.75rem 1rem 0.25rem;
+    padding: 0.125rem;
+    border-radius: 0.625rem;
+
+    background-color: var(--color-background-secondary);
+  }
+
+  .period {
+    cursor: pointer;
+
+    flex: 1;
+
+    height: 2rem;
+    border: 0;
+    border-radius: 0.5rem;
+
+    font: inherit;
+    font-size: 0.8125rem;
+    color: var(--color-text-secondary);
+    white-space: nowrap;
+
+    background: none;
+
+    transition:
+      background-color 0.15s ease-out,
+      color 0.15s ease-out;
+
+    &.on {
+      color: var(--color-text);
+      background-color: var(--color-background);
+    }
+
+    &:focus-visible {
+      outline: 2px solid var(--color-primary);
+      outline-offset: -2px;
+    }
+
+    @media (pointer: coarse) {
+      height: 2.75rem;
+    }
   }
 
   section {
-    display: flex;
-    flex-direction: column;
-    gap: 0.75rem;
+    padding: 0.5rem 0;
+
+    & + section {
+      border-top: 1px solid var(--color-borders);
+    }
   }
 
-  h3 {
-    margin: 0;
-    font-size: 0.75rem;
+  .hero {
+    padding: 0.75rem 1rem 0.875rem;
+  }
+
+  .total-line {
+    display: flex;
+    flex-wrap: wrap;
+    gap: 0 0.625rem;
+    align-items: baseline;
+  }
+
+  .total {
+    font-size: 1.875rem;
     font-weight: var(--font-weight-medium);
-    color: var(--color-text-secondary);
-    text-transform: uppercase;
-    letter-spacing: 0.03em;
+    font-variant-numeric: tabular-nums;
+    line-height: 1.2;
+    letter-spacing: -0.01em;
   }
 
-  .stats {
-    display: flex;
-    gap: 1.5rem;
-  }
-
-  .stat {
-    display: flex;
-    flex-direction: column;
-    gap: 0.25rem;
-  }
-
-  .value {
-    font-size: 1.5rem;
-    font-weight: var(--font-weight-medium);
-    color: var(--color-text);
-  }
-
-  .caption {
-    font-size: 0.75rem;
+  .count {
+    font-size: 0.875rem;
     color: var(--color-text-secondary);
   }
 
   .status {
+    margin: 0.25rem 0 0;
     font-size: 0.9375rem;
     color: var(--color-text-secondary);
 
@@ -246,49 +389,80 @@
     }
   }
 
-  .muted {
-    margin: 0;
-    font-size: 0.8125rem;
+  .note {
+    margin: 0.5rem 0 0;
+    font-size: 0.875rem;
+    line-height: 1.4;
     color: var(--color-text-secondary);
   }
 
-  .changes {
+  .section-title {
     display: flex;
-    flex-direction: column;
-    gap: 0.5rem;
-    margin: 0;
-    padding: 0;
-    list-style: none;
-  }
+    gap: 0.75rem;
+    align-items: baseline;
+    justify-content: space-between;
+
+    padding: 0.375rem 1rem 0.625rem;
 
-  .changes li {
-    display: flex;
-    align-items: center;
-    gap: 0.5rem;
     font-size: 0.8125rem;
-  }
+    font-variant-numeric: tabular-nums;
+    color: var(--color-text-secondary);
 
-  .dot {
-    width: 0.5rem;
-    height: 0.5rem;
-    flex-shrink: 0;
-    border-radius: 50%;
-    background-color: var(--color-text-secondary);
-
-    &.online {
-      background-color: var(--color-primary);
+    h3 {
+      margin: 0;
+      font-size: inherit;
+      font-weight: var(--font-weight-medium);
+      color: var(--color-primary);
+      white-space: nowrap;
     }
   }
 
-  .label {
-    flex: 1;
-    overflow: hidden;
-    text-overflow: ellipsis;
+  .rows {
+    margin: 0;
+  }
+
+  .replies {
+    margin-top: 0.5rem;
+  }
+
+  .row {
+    display: flex;
+    gap: 1rem;
+    align-items: center;
+    justify-content: space-between;
+
+    min-height: 2.5rem;
+    padding: 0 1rem;
+
+    font-size: 0.9375rem;
+  }
+
+  dt {
+    color: var(--color-text);
+  }
+
+  dd {
+    margin: 0;
+    font-variant-numeric: tabular-nums;
+    color: var(--color-text-secondary);
     white-space: nowrap;
   }
 
-  .time {
-    flex-shrink: 0;
+  .state {
+    display: flex;
+    flex-direction: column;
+    gap: 0.25rem;
+    align-items: center;
+
+    margin: 0;
+    padding: 2rem 1rem;
+
+    font-size: 0.9375rem;
     color: var(--color-text-secondary);
+    text-align: center;
+
+    p {
+      margin: 0;
+    }
   }
 </style>

frontend/src/lib/components/presence/OnlineDays.svelte

@@ -0,0 +1,144 @@
+<script lang="ts">
+  import type { PresenceDay } from "#lib/api/types.js";
+  import { formatDay, parseDay } from "#lib/format/datetime.js";
+  import { formatSpan } from "#lib/format/presence.js";
+
+  interface Props {
+    days: PresenceDay[];
+  }
+
+  const { days }: Props = $props();
+
+  const SECONDS_IN_HOUR = 3600;
+  const SECONDS_IN_DAY = 86_400;
+
+  const TEXT = {
+    bar: (day: string, online: number, missing: number) => {
+      if (missing >= SECONDS_IN_DAY - SECONDS_IN_HOUR) {
+        return `${day}, нет данных`;
+      }
+      const gap =
+        missing >= SECONDS_IN_HOUR ? `, нет данных ${formatSpan(missing)}` : "";
+      return `${day}, ${formatSpan(online)} в сети${gap}`;
+    },
+    today: "сегодня",
+  };
+
+  const peak = $derived(Math.max(1, ...days.map((day) => day.online_seconds)));
+  const first = $derived(days[0]);
+
+  function label(day: string): string {
+    return formatDay(parseDay(day).toISOString());
+  }
+
+  function absent(day: PresenceDay, index: number): number {
+    if (index === days.length - 1) {
+      return 0;
+    }
+    return Math.max(0, SECONDS_IN_DAY - day.covered_seconds);
+  }
+</script>
+
+<div class="days">
+  <div class="chart">
+    <span class="peak">{formatSpan(peak)}</span>
+    <div class={["bars", { dense: days.length > 45 }]}>
+      {#each days as day, index (day.day)}
+        <div
+          class={["slot", { empty: day.covered_seconds < SECONDS_IN_HOUR }]}
+          title={TEXT.bar(
+            label(day.day),
+            day.online_seconds,
+            absent(day, index)
+          )}
+        >
+          <span
+            class={["bar", { zero: day.online_seconds === 0 }]}
+            style:height="{(day.online_seconds / peak) * 100}%"
+          ></span>
+        </div>
+      {/each}
+    </div>
+  </div>
+  {#if first}
+    <div class="axis">
+      <span>{label(first.day)}</span>
+      <span>{TEXT.today}</span>
+    </div>
+  {/if}
+</div>
+
+<style lang="scss">
+  .days {
+    padding: 0 1rem;
+  }
+
+  .chart {
+    position: relative;
+    padding-top: 1.125rem;
+    border-top: 1px dashed var(--color-borders);
+  }
+
+  .peak {
+    position: absolute;
+    top: 0.125rem;
+    left: 0;
+
+    font-size: 0.6875rem;
+    font-variant-numeric: tabular-nums;
+    color: var(--color-text-secondary);
+  }
+
+  .bars {
+    display: flex;
+    gap: 3px;
+    align-items: flex-end;
+    height: 6rem;
+
+    &.dense {
+      gap: 1px;
+    }
+  }
+
+  .slot {
+    display: flex;
+    flex: 1;
+    align-items: flex-end;
+    height: 100%;
+
+    &.empty {
+      border-radius: 2px 2px 0 0;
+      background: repeating-linear-gradient(
+        135deg,
+        rgba(var(--color-text-secondary-rgb), 0.35) 0 1px,
+        transparent 1px 4px
+      );
+    }
+  }
+
+  .bar {
+    width: 100%;
+    min-height: 2px;
+    border-radius: 2px 2px 0 0;
+    background-color: var(--color-primary);
+
+    &.zero {
+      background-color: rgba(var(--color-text-secondary-rgb), 0.3);
+    }
+
+    .empty & {
+      min-height: 0;
+    }
+  }
+
+  .axis {
+    display: flex;
+    justify-content: space-between;
+
+    margin-top: 0.375rem;
+
+    font-size: 0.6875rem;
+    font-variant-numeric: tabular-nums;
+    color: var(--color-text-secondary);
+  }
+</style>

frontend/src/lib/components/presence/PresenceHeatmap.svelte

@@ -1,116 +1,217 @@
 <script lang="ts">
-  import type { PresenceHourly } from "#lib/api/types.js";
+  import type { PresenceHour } from "#lib/api/types.js";
+  import { formatSpan } from "#lib/format/presence.js";
 
   interface Props {
-    hourly: PresenceHourly[];
+    week: PresenceHour[];
   }
 
-  const { hourly }: Props = $props();
+  const { week }: Props = $props();
 
-  const DAYS = ["Пн", "Вт", "Ср", "Чт", "Пт", "Сб", "Вс"];
-  const HOURS = Array.from({ length: 24 }, (_, hour) => hour);
-  const HOUR_TICKS = new Set([0, 6, 12, 18]);
-
-  interface Cell {
-    online: number;
-    total: number;
+  const TEXT = {
+    cell: (day: string, cell: PresenceHour) => {
+      const slot = `${day}, ${cell.hour}:00`;
+      if (cell.hours === 0) {
+        return slot;
       }
+      if (cell.online_minutes === null) {
+        return `${slot}, нет данных`;
+      }
+      return `${slot}, в среднем ${formatSpan(cell.online_minutes * 60)} в сети`;
+    },
+    days: ["Пн", "Вт", "Ср", "Чт", "Пт", "Сб", "Вс"],
+    empty: "нет данных",
+    max: (minutes: number) => `до ${formatSpan(minutes * 60)}`,
+  };
 
-  const grid = $derived.by(() => {
-    const cells: Cell[][] = DAYS.map(() =>
-      HOURS.map(() => ({ online: 0, total: 0 }))
+  const HOURS_IN_DAY = 24;
+  const HOUR_TICKS = [0, 6, 12, 18];
+  const MIN_SHADE = 0.18;
+
+  const rows = $derived(
+    TEXT.days.map((_, weekday) =>
+      week
+        .filter((cell) => cell.weekday === weekday)
+        .sort((a, b) => a.hour - b.hour)
+    )
   );
-    for (const bucket of hourly) {
-      const date = new Date(bucket.bucket);
-      const day = (date.getDay() + 6) % 7;
-      const cell = cells[day]?.[date.getHours()];
-      if (cell) {
-        cell.online += bucket.online_samples;
-        cell.total += bucket.samples;
-      }
-    }
-    return cells;
-  });
+  const peak = $derived(
+    Math.max(0, ...week.map((cell) => cell.online_minutes ?? 0))
+  );
+  const hasGaps = $derived(week.some(missing));
 
-  function intensity(cell: Cell): number {
-    return cell.total > 0 ? cell.online / cell.total : 0;
+  function missing(cell: PresenceHour): boolean {
+    return cell.hours > 0 && cell.online_minutes === null;
   }
 
-  function cellTitle(day: number, hour: number, cell: Cell): string {
-    const pct = cell.total > 0 ? Math.round(intensity(cell) * 100) : 0;
-    return `${DAYS[day]} ${hour}:00 — ${pct}% online`;
+  function shade(minutes: number | null): number {
+    if (minutes === null || minutes === 0 || peak === 0) {
+      return 0;
+    }
+    return MIN_SHADE + (1 - MIN_SHADE) * (minutes / peak);
   }
 </script>
 
 <div class="heatmap">
-  {#each grid as row, day (day)}
-    <div class="heat-row">
-      <span class="day-label">{DAYS[day]}</span>
+  {#each rows as cells, weekday (weekday)}
+    <div class="row">
+      <span class="day">{TEXT.days[weekday]}</span>
       <div class="cells">
-        {#each row as cell, hour (hour)}
+        {#each cells as cell (cell.hour)}
           <span
-            class="cell"
-            title={cellTitle(day, hour, cell)}
-            style:--i={intensity(cell)}
-            class:empty={cell.total === 0}
+            class={[
+              "cell",
+              {
+                empty: missing(cell),
+                outside: cell.hours === 0,
+                zero: cell.online_minutes === 0,
+              },
+            ]}
+            title={TEXT.cell(TEXT.days[weekday] ?? "", cell)}
+            style:--shade="{shade(cell.online_minutes) * 100}%"
           ></span>
         {/each}
       </div>
     </div>
   {/each}
-  <div class="heat-row axis">
-    <span class="day-label"></span>
-    <div class="cells">
-      {#each HOURS as hour (hour)}
-        <span class="tick">{HOUR_TICKS.has(hour) ? hour : ""}</span>
+  <div class="row">
+    <span class="day"></span>
+    <div class="ticks">
+      {#each HOUR_TICKS as hour (hour)}
+        <span style:left="{(hour / HOURS_IN_DAY) * 100}%">{hour}</span>
       {/each}
     </div>
   </div>
+  <div class="legend">
+    <span class="key"><span class="swatch zero"></span>0</span>
+    {#if peak > 0}
+      <span class="key">
+        <span class="scale"></span>
+        {TEXT.max(peak)}
+      </span>
+    {/if}
+    {#if hasGaps}
+      <span class="key">
+        <span class="swatch empty"></span>
+        {TEXT.empty}
+      </span>
+    {/if}
+  </div>
 </div>
 
 <style lang="scss">
   .heatmap {
     display: flex;
     flex-direction: column;
-    gap: 3px;
+    gap: 2px;
+    padding: 0 1rem;
   }
 
-  .heat-row {
+  .row {
     display: flex;
-    align-items: center;
     gap: 0.5rem;
+    align-items: center;
   }
 
-  .day-label {
-    width: 1.5rem;
+  .day {
     flex-shrink: 0;
-    font-size: 0.6875rem;
+    width: 1.375rem;
+    font-size: 0.75rem;
     color: var(--color-text-secondary);
-    text-align: right;
   }
 
   .cells {
     display: grid;
     flex: 1;
-    grid-template-columns: repeat(24, 1fr);
-    gap: 3px;
+    grid-template-columns: repeat(24, minmax(0, 1fr));
+    gap: 2px;
   }
 
   .cell {
     aspect-ratio: 1;
     border-radius: 2px;
-    background-color: var(--color-primary);
-    opacity: calc(0.12 + 0.88 * var(--i));
+    background-color: color-mix(
+      in srgb,
+      var(--color-primary) var(--shade),
+      transparent
+    );
+
+    &.zero {
+      background-color: rgba(var(--color-text-secondary-rgb), 0.12);
+    }
+
+    &.outside {
+      background: none;
+    }
 
     &.empty {
-      background-color: var(--color-text-secondary);
-      opacity: 0.08;
+      background: repeating-linear-gradient(
+        135deg,
+        rgba(var(--color-text-secondary-rgb), 0.45) 0 1px,
+        transparent 1px 3px
+      );
     }
   }
 
-  .tick {
-    font-size: 0.625rem;
+  .ticks {
+    position: relative;
+    flex: 1;
+    height: 1rem;
+
+    span {
+      position: absolute;
+      top: 0.125rem;
+      font-size: 0.6875rem;
+      font-variant-numeric: tabular-nums;
       color: var(--color-text-secondary);
-    text-align: left;
+    }
+  }
+
+  .legend {
+    display: flex;
+    flex-wrap: wrap;
+    gap: 0.25rem 0.75rem;
+    align-items: center;
+
+    margin: 0.375rem 0 0 1.875rem;
+
+    font-size: 0.75rem;
+    font-variant-numeric: tabular-nums;
+    color: var(--color-text-secondary);
+  }
+
+  .key {
+    display: inline-flex;
+    gap: 0.375rem;
+    align-items: center;
+  }
+
+  .scale {
+    width: 2.5rem;
+    height: 0.625rem;
+    border-radius: 2px;
+    background: linear-gradient(
+      90deg,
+      color-mix(in srgb, var(--color-primary) 18%, transparent),
+      var(--color-primary)
+    );
+  }
+
+  .swatch {
+    width: 0.625rem;
+    height: 0.625rem;
+    border-radius: 2px;
+
+    &.zero {
+      background-color: rgba(var(--color-text-secondary-rgb), 0.12);
+    }
+
+    &.empty {
+      background: repeating-linear-gradient(
+        135deg,
+        rgba(var(--color-text-secondary-rgb), 0.45) 0 1px,
+        transparent 1px 3px
+      );
+    }
   }
 </style>

frontend/src/lib/components/presence/PresenceSessions.svelte

@@ -0,0 +1,205 @@
+<script lang="ts">
+  import { getPresenceSessions } from "#lib/api/endpoints.js";
+  import type { PresenceSession } from "#lib/api/types.js";
+  import Button from "#lib/components/ui/Button.svelte";
+  import Spinner from "#lib/components/ui/Spinner.svelte";
+  import { formatLongDay, formatTime } from "#lib/format/datetime.js";
+  import { formatSpan } from "#lib/format/presence.js";
+
+  interface Props {
+    days: number;
+    first: PresenceSession[];
+    pageSize: number;
+    peerId: number;
+    tz: string;
+  }
+
+  const { days, first, pageSize, peerId, tz }: Props = $props();
+
+  const TEXT = {
+    failed: "Не удалось загрузить сессии.",
+    more: "Показать ещё",
+    none: "За этот период в сети не был(а).",
+    now: "в сети",
+    retry: "Повторить",
+    since: (time: string) => `с ${time}`,
+    span: (from: string, to: string) => (from === to ? from : `${from}–${to}`),
+    today: "Сегодня",
+    yesterday: "Вчера",
+  };
+
+  const MS_IN_DAY = 86_400_000;
+
+  let extra = $state<PresenceSession[]>([]);
+  let loading = $state(false);
+  let failed = $state(false);
+  let done = $state(false);
+
+  const sessions = $derived([...first, ...extra]);
+  const exhausted = $derived(done || first.length < pageSize);
+  const groups = $derived.by(() => {
+    const result: { label: string; sessions: PresenceSession[] }[] = [];
+    for (const session of sessions) {
+      const label = dayLabel(new Date(session.started));
+      const last = result.at(-1);
+      if (last?.label === label) {
+        last.sessions.push(session);
+      } else {
+        result.push({ label, sessions: [session] });
+      }
+    }
+    return result;
+  });
+
+  function dayLabel(date: Date): string {
+    const today = new Date();
+    if (date.toDateString() === today.toDateString()) {
+      return TEXT.today;
+    }
+    if (
+      date.toDateString() ===
+      new Date(today.getTime() - MS_IN_DAY).toDateString()
+    ) {
+      return TEXT.yesterday;
+    }
+    const text = formatLongDay(date);
+    return text.charAt(0).toUpperCase() + text.slice(1);
+  }
+
+  async function loadMore() {
+    if (loading) {
+      return;
+    }
+    loading = true;
+    failed = false;
+    try {
+      const batch = await getPresenceSessions(peerId, days, tz, {
+        limit: pageSize,
+        offset: sessions.length,
+      });
+      const seen = new Set(sessions.map((session) => session.started));
+      extra = [
+        ...extra,
+        ...batch.filter((session) => !seen.has(session.started)),
+      ];
+      done = batch.length < pageSize;
+    } catch {
+      failed = true;
+    } finally {
+      loading = false;
+    }
+  }
+</script>
+
+{#if sessions.length === 0}
+  <p class="state">{TEXT.none}</p>
+{:else}
+  {#each groups as group (group.label)}
+    <h4 class="day">{group.label}</h4>
+    <ul>
+      {#each group.sessions as session (session.started)}
+        <li>
+          <span>
+            {session.ongoing
+              ? TEXT.since(formatTime(session.started))
+              : TEXT.span(
+                  formatTime(session.started),
+                  formatTime(session.ended)
+                )}
+          </span>
+          <span class={["length", { online: session.ongoing }]}>
+            {session.ongoing ? TEXT.now : formatSpan(session.seconds)}
+          </span>
+        </li>
+      {/each}
+    </ul>
+  {/each}
+  {#if loading}
+    <div class="state"><Spinner /></div>
+  {:else if failed}
+    <div class="state">
+      <p>{TEXT.failed}</p>
+      <Button onclick={loadMore} smaller variant="text">{TEXT.retry}</Button>
+    </div>
+  {:else if !exhausted}
+    <button class="more" onclick={loadMore} type="button">{TEXT.more}</button>
+  {/if}
+{/if}
+
+<style lang="scss">
+  .day {
+    margin: 0;
+    padding: 0.625rem 1rem 0.25rem;
+
+    font-size: 0.8125rem;
+    font-weight: var(--font-weight-normal);
+    color: var(--color-text-secondary);
+  }
+
+  ul {
+    margin: 0;
+    padding: 0;
+    list-style: none;
+  }
+
+  li {
+    display: flex;
+    gap: 1rem;
+    align-items: center;
+    justify-content: space-between;
+
+    min-height: 2.5rem;
+    padding: 0 1rem;
+
+    font-size: 0.9375rem;
+    font-variant-numeric: tabular-nums;
+  }
+
+  .length {
+    font-size: 0.875rem;
+    color: var(--color-text-secondary);
+
+    &.online {
+      color: var(--color-primary);
+    }
+  }
+
+  .state {
+    display: flex;
+    flex-direction: column;
+    gap: 0.25rem;
+    align-items: center;
+
+    margin: 0;
+    padding: 1.5rem 1rem;
+
+    font-size: 0.9375rem;
+    color: var(--color-text-secondary);
+    text-align: center;
+
+    p {
+      margin: 0;
+    }
+  }
+
+  .more {
+    cursor: pointer;
+
+    width: calc(100% - 1rem);
+    margin: 0.5rem;
+    padding: 0.5rem;
+    border: 0;
+    border-radius: 0.5rem;
+
+    font: inherit;
+    font-size: 0.875rem;
+    color: var(--color-primary);
+
+    background-color: var(--color-background-secondary);
+
+    &:focus-visible {
+      outline: 2px solid var(--color-primary);
+      outline-offset: 1px;
+    }
+  }
+</style>

frontend/src/lib/components/presence/VolumeChart.svelte

@@ -1,5 +1,6 @@
 <script lang="ts">
   import type { VolumeBucket } from "#lib/api/types.js";
+  import { formatDay, parseDay } from "#lib/format/datetime.js";
 
   interface Props {
     volume: VolumeBucket[];
@@ -7,47 +8,104 @@
 
   const { volume }: Props = $props();
 
-  const max = $derived(Math.max(1, ...volume.map((bucket) => bucket.total)));
+  const TEXT = {
+    bar: (day: string, bucket: VolumeBucket) =>
+      bucket.total === 0
+        ? `${day}, нет сообщений`
+        : `${day}, всего ${bucket.total}: входящих ${bucket.incoming}, моих ${bucket.outgoing}`,
+    incoming: "входящие",
+    outgoing: "мои",
+    today: "сегодня",
+  };
 
-  function barTitle(bucket: VolumeBucket): string {
-    return `${bucket.bucket.slice(0, 10)} — всего ${bucket.total} (вх ${bucket.incoming} / исх ${bucket.outgoing})`;
+  const peak = $derived(Math.max(1, ...volume.map((bucket) => bucket.total)));
+  const first = $derived(volume[0]);
+
+  function label(day: string): string {
+    return formatDay(parseDay(day).toISOString());
   }
 </script>
 
 <div class="volume">
-  <div class="bars">
+  <div class="chart">
+    <span class="peak">{peak}</span>
+    <div class={["bars", { dense: volume.length > 45 }]}>
       {#each volume as bucket (bucket.bucket)}
+        <div class="slot" title={TEXT.bar(label(bucket.bucket), bucket)}>
           <div
-        class="bar"
-        title={barTitle(bucket)}
-        style:height={`${(bucket.total / max) * 100}%`}
+            class={["bar", { zero: bucket.total === 0 }]}
+            style:height="{(bucket.total / peak) * 100}%"
           >
-        <div class="seg out" style:flex-grow={bucket.outgoing}></div>
             <div class="seg in" style:flex-grow={bucket.incoming}></div>
+            <div class="seg out" style:flex-grow={bucket.outgoing}></div>
+          </div>
         </div>
       {/each}
     </div>
+  </div>
+  {#if first}
+    <div class="axis">
+      <span>{label(first.bucket)}</span>
+      <span>{TEXT.today}</span>
+    </div>
+  {/if}
   <div class="legend">
-    <span class="key"><span class="swatch out"></span>исходящие</span>
-    <span class="key"><span class="swatch in"></span>входящие</span>
+    <span class="key"><span class="swatch in"></span>{TEXT.incoming}</span>
+    <span class="key"><span class="swatch out"></span>{TEXT.outgoing}</span>
   </div>
 </div>
 
 <style lang="scss">
+  .volume {
+    padding: 0 1rem;
+  }
+
+  .chart {
+    position: relative;
+    padding-top: 1.125rem;
+    border-top: 1px dashed var(--color-borders);
+  }
+
+  .peak {
+    position: absolute;
+    top: 0.125rem;
+    left: 0;
+
+    font-size: 0.6875rem;
+    font-variant-numeric: tabular-nums;
+    color: var(--color-text-secondary);
+  }
+
   .bars {
     display: flex;
+    gap: 3px;
     align-items: flex-end;
+    height: 6rem;
+
+    &.dense {
       gap: 1px;
-    height: 7.5rem;
+    }
+  }
+
+  .slot {
+    display: flex;
+    flex: 1;
+    align-items: flex-end;
+    height: 100%;
   }
 
   .bar {
     display: flex;
-    flex: 1;
     flex-direction: column;
+
+    width: 100%;
     min-height: 2px;
     overflow: hidden;
     border-radius: 2px 2px 0 0;
+
+    &.zero {
+      background-color: rgba(var(--color-text-secondary-rgb), 0.3);
+    }
   }
 
   .seg.out {
@@ -55,8 +113,18 @@
   }
 
   .seg.in {
-    background-color: var(--color-text-secondary);
-    opacity: 0.4;
+    background-color: color-mix(in srgb, var(--color-primary) 40%, transparent);
+  }
+
+  .axis {
+    display: flex;
+    justify-content: space-between;
+
+    margin-top: 0.375rem;
+
+    font-size: 0.6875rem;
+    font-variant-numeric: tabular-nums;
+    color: var(--color-text-secondary);
   }
 
   .legend {
@@ -69,8 +137,8 @@
 
   .key {
     display: flex;
-    align-items: center;
     gap: 0.375rem;
+    align-items: center;
   }
 
   .swatch {
@@ -83,8 +151,11 @@
     }
 
     &.in {
-      background-color: var(--color-text-secondary);
-      opacity: 0.4;
+      background-color: color-mix(
+        in srgb,
+        var(--color-primary) 40%,
+        transparent
+      );
     }
   }
 </style>

frontend/src/lib/components/read/MessageReadItem.svelte

@@ -0,0 +1,104 @@
+<script lang="ts">
+  import { ContextMenu } from "bits-ui";
+  import { untrack } from "svelte";
+  import type { MessageView } from "#lib/api/types.js";
+  import Avatar from "#lib/components/ui/Avatar.svelte";
+  import Icon from "#lib/components/ui/Icon.svelte";
+  import Spinner from "#lib/components/ui/Spinner.svelte";
+  import { peerColorIndex, peerName } from "#lib/format/peer.js";
+  import { readLine } from "#lib/format/read.js";
+  import { t } from "#lib/i18n/locale.svelte.js";
+  import { reads } from "#lib/stores/reads.svelte.js";
+  import { ui } from "#lib/stores/ui.svelte.js";
+
+  interface Props {
+    message: MessageView;
+  }
+
+  const AVATARS = 3;
+
+  let { message }: Props = $props();
+
+  const entry = $derived(reads.get(message.chat_id, message.message_id));
+  const fetching = $derived(entry?.fetching ?? false);
+  const shown = $derived(readLine(message, entry?.info ?? null, fetching));
+
+  $effect(() => {
+    const chatId = message.chat_id;
+    const messageId = message.message_id;
+    untrack(() => reads.open(chatId, messageId));
+  });
+
+  function openReaders() {
+    ui.openMessagePanel("readers", message.message_id);
+  }
+</script>
+
+{#if shown?.kind === "readers"}
+  <ContextMenu.Item class="bg-menu-item read-item" onSelect={openReaders}>
+    <Icon name="group" size="1.125rem" />
+    <span class="label"
+      >{t("read.readers", { count: shown.readers.length })}</span
+    >
+    {#if fetching}
+      <Spinner color="gray" size="1rem" />
+    {/if}
+    <span class="avatars">
+      {#each shown.readers.slice(0, AVATARS) as reader (reader.peer_id)}
+        <Avatar
+          avatar={{ id: reader.peer_id, kind: "peer" }}
+          colorKey={peerColorIndex(reader.peer_id)}
+          hasAvatar={reader.peer?.has_avatar ?? false}
+          name={peerName(reader.peer) || String(reader.peer_id)}
+          size={1.5}
+        />
+      {/each}
+    </span>
+  </ContextMenu.Item>
+  <ContextMenu.Separator class="bg-menu-separator" />
+{:else if shown}
+  <div class="bg-menu-item read-item static" class:muted={shown.muted}>
+    <Icon name={shown.icon} size="1.125rem" />
+    <span class="label">{shown.text}</span>
+    {#if fetching}
+      <Spinner color="gray" size="1rem" />
+    {/if}
+  </div>
+  <ContextMenu.Separator class="bg-menu-separator" />
+{/if}
+
+<style lang="scss">
+  :global(.bg-menu-item.read-item) {
+    min-height: 2.5rem;
+  }
+
+  .static {
+    cursor: default;
+
+    &:hover {
+      background-color: transparent;
+    }
+  }
+
+  .muted {
+    color: var(--color-text-secondary);
+  }
+
+  .label {
+    flex: 1;
+    white-space: nowrap;
+  }
+
+  .avatars {
+    display: flex;
+    margin-inline-start: 0.25rem;
+
+    & > :global(.Avatar) {
+      border: 2px solid var(--color-background);
+    }
+
+    & > :global(.Avatar + .Avatar) {
+      margin-inline-start: -0.5rem;
+    }
+  }
+</style>

frontend/src/lib/components/read/ReadersPanel.svelte

@@ -0,0 +1,124 @@
+<script lang="ts">
+  import { untrack } from "svelte";
+  import Avatar from "#lib/components/ui/Avatar.svelte";
+  import EmptyState from "#lib/components/ui/EmptyState.svelte";
+  import Spinner from "#lib/components/ui/Spinner.svelte";
+  import { peerColorIndex, peerName } from "#lib/format/peer.js";
+  import { readWhen } from "#lib/format/read.js";
+  import { t } from "#lib/i18n/locale.svelte.js";
+  import { reads } from "#lib/stores/reads.svelte.js";
+  import { ui } from "#lib/stores/ui.svelte.js";
+  import { goto } from "$app/navigation";
+  import { page } from "$app/state";
+
+  const chatId = $derived(
+    page.params.chatId ? Number(page.params.chatId) : null
+  );
+  const messageId = $derived(ui.panelMessageId);
+  const entry = $derived(
+    chatId === null || messageId === null
+      ? undefined
+      : reads.get(chatId, messageId)
+  );
+  const readers = $derived(entry?.info.readers ?? []);
+
+  $effect(() => {
+    const cid = chatId;
+    const mid = messageId;
+    if (cid !== null && mid !== null) {
+      untrack(() => reads.open(cid, mid));
+    }
+  });
+
+  function openProfile(peerId: number) {
+    goto(`/app/${peerId}`);
+    ui.openPanel("profile");
+  }
+</script>
+
+{#if entry === undefined}
+  <div class="center"><Spinner /></div>
+{:else if readers.length === 0}
+  <EmptyState title={t("read.readers.empty")} />
+{:else}
+  <ul class="readers">
+    {#each readers as reader (reader.peer_id)}
+      {@const name = peerName(reader.peer) || String(reader.peer_id)}
+      <li>
+        <button onclick={() => openProfile(reader.peer_id)} type="button">
+          <Avatar
+            avatar={{ id: reader.peer_id, kind: "peer" }}
+            colorKey={peerColorIndex(reader.peer_id)}
+            hasAvatar={reader.peer?.has_avatar ?? false}
+            {name}
+            size={2.625}
+          />
+          <span class="info">
+            <span class="name">{name}</span>
+            <span class="time">{readWhen(reader.read_at)}</span>
+          </span>
+        </button>
+      </li>
+    {/each}
+  </ul>
+{/if}
+
+<style lang="scss">
+  .center {
+    display: flex;
+    justify-content: center;
+    padding: 2rem 0;
+  }
+
+  .readers {
+    display: flex;
+    flex-direction: column;
+    margin: 0;
+    padding: 0.5rem;
+    list-style: none;
+  }
+
+  button {
+    cursor: pointer;
+
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+
+    width: 100%;
+    padding: 0.4375rem 0.75rem;
+    border: 0;
+    border-radius: var(--border-radius-default-small);
+
+    font: inherit;
+    color: inherit;
+    text-align: start;
+
+    background: transparent;
+
+    &:hover,
+    &:focus-visible {
+      background-color: var(--color-chat-hover);
+    }
+  }
+
+  .info {
+    display: flex;
+    flex-direction: column;
+    min-width: 0;
+  }
+
+  .name {
+    overflow: hidden;
+
+    font-weight: var(--font-weight-medium);
+    color: var(--color-text);
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+
+  .time {
+    font-size: 0.875rem;
+    color: var(--color-text-secondary);
+  }
+</style>

frontend/src/lib/format/datetime.ts

@@ -9,19 +9,25 @@ const OPTIONS = {
     month: "short",
     year: "numeric",
   },
+  longDay: { day: "numeric", month: "long", weekday: "long" },
+  offset: { timeZoneName: "shortOffset" },
   time: { hour: "2-digit", minute: "2-digit" },
 } satisfies Record<string, Intl.DateTimeFormatOptions>;
 
 const formatters = new Map<string, Intl.DateTimeFormat>();
 
-function format(kind: keyof typeof OPTIONS, date: Date): string {
+function formatter(kind: keyof typeof OPTIONS): Intl.DateTimeFormat {
   const key = `${locale.tag}:${kind}`;
-  let formatter = formatters.get(key);
-  if (!formatter) {
-    formatter = new Intl.DateTimeFormat(locale.tag, OPTIONS[kind]);
-    formatters.set(key, formatter);
+  let cached = formatters.get(key);
+  if (!cached) {
+    cached = new Intl.DateTimeFormat(locale.tag, OPTIONS[kind]);
+    formatters.set(key, cached);
   }
-  return formatter.format(date);
+  return cached;
+}
+
+function format(kind: keyof typeof OPTIONS, date: Date): string {
+  return formatter(kind).format(date);
 }
 
 export function formatTime(iso: string): string {
@@ -47,3 +53,24 @@ export function formatListDate(iso: string | null): string {
   }
   return format("day", date);
 }
+
+export function formatLongDay(date: Date): string {
+  return format("longDay", date);
+}
+
+export function parseDay(value: string): Date {
+  const [year, month, date] = value.split("-").map(Number);
+  return new Date(year ?? 0, (month ?? 1) - 1, date ?? 1);
+}
+
+export function browserTimeZone(): string {
+  return Intl.DateTimeFormat().resolvedOptions().timeZone;
+}
+
+export function timeZoneLabel(): string {
+  return (
+    formatter("offset")
+      .formatToParts(new Date())
+      .find((part) => part.type === "timeZoneName")?.value ?? browserTimeZone()
+  );
+}

frontend/src/lib/format/presence.ts

@@ -1,37 +1,117 @@
 import type { PresenceSample } from "#lib/api/types.js";
-import { formatListDate } from "#lib/format/datetime.js";
+import { formatDay, formatTime } from "#lib/format/datetime.js";
+import { plural } from "#lib/format/shares.js";
 
-export function isOnline(sample: PresenceSample | null): boolean {
-  if (sample === null || sample.status !== "online") {
+const SECONDS_IN_MINUTE = 60;
+const MINUTES_IN_HOUR = 60;
+const SECONDS_IN_HOUR = 3600;
+const MS_IN_MINUTE = 60_000;
+const SECONDS_IN_DAY = 86_400;
+const MS_IN_DAY = 86_400_000;
+
+const TEXT = {
+  ago: (minutes: number) =>
+    `был(а) ${minutes} ${plural(minutes, "минуту", "минуты", "минут")} назад`,
+  days: (days: number) => `${days} ${plural(days, "день", "дня", "дней")}`,
+  hours: (hours: number) => `${hours} ч`,
+  hoursMinutes: (hours: number, minutes: number) => `${hours} ч ${minutes} мин`,
+  justNow: "был(а) только что",
+  lastMonth: "был(а) в этом месяце",
+  lastWeek: "был(а) на этой неделе",
+  longAgo: "был(а) давно",
+  minutes: (minutes: number) => `${minutes} мин`,
+  offline: "не в сети",
+  on: (day: string, time: string) => `был(а) ${day} в ${time}`,
+  online: "в сети",
+  recently: "был(а) недавно",
+  seconds: (seconds: number) => `${seconds} с`,
+  today: (time: string) => `был(а) сегодня в ${time}`,
+  yesterday: (time: string) => `был(а) вчера в ${time}`,
+};
+
+const FUZZY: Record<string, string> = {
+  last_month: TEXT.lastMonth,
+  last_week: TEXT.lastWeek,
+  long_time_ago: TEXT.longAgo,
+  recently: TEXT.recently,
+};
+
+export function isOnline(
+  sample: PresenceSample | null,
+  now = Date.now()
+): boolean {
+  if (sample?.status !== "online" || sample.next_offline_date === null) {
     return false;
   }
-  if (sample.next_offline_date === null) {
-    return false;
-  }
-  return new Date(sample.next_offline_date).getTime() > Date.now();
+  return new Date(sample.next_offline_date).getTime() > now;
 }
 
-export function formatPresence(sample: PresenceSample): string {
-  switch (sample.status) {
-    case "online":
-      return isOnline(sample)
-        ? "online"
-        : lastSeen(sample.last_online_date ?? sample.ts);
-    case "recently":
-      return "last seen recently";
-    case "last_week":
-      return "last seen within a week";
-    case "last_month":
-      return "last seen within a month";
-    case "long_time_ago":
-      return "last seen a long time ago";
-    default:
+function lastSeen(iso: string, now: number): string {
+  const date = new Date(iso);
+  const minutes = Math.floor((now - date.getTime()) / MS_IN_MINUTE);
+  if (minutes < 1) {
+    return TEXT.justNow;
+  }
+  if (minutes < MINUTES_IN_HOUR) {
+    return TEXT.ago(minutes);
+  }
+  const time = formatTime(iso);
+  const today = new Date(now);
+  if (date.toDateString() === today.toDateString()) {
+    return TEXT.today(time);
+  }
+  if (date.toDateString() === new Date(now - MS_IN_DAY).toDateString()) {
+    return TEXT.yesterday(time);
+  }
+  return TEXT.on(formatDay(iso), time);
+}
+
+export function formatPresence(
+  sample: PresenceSample,
+  now = Date.now()
+): string {
+  if (sample.status === "online") {
+    return isOnline(sample, now)
+      ? TEXT.online
+      : lastSeen(sample.next_offline_date ?? sample.ts, now);
+  }
+  const fuzzy = FUZZY[sample.status];
+  if (fuzzy) {
+    return fuzzy;
+  }
   return sample.last_online_date
-        ? lastSeen(sample.last_online_date)
-        : "offline";
-  }
+    ? lastSeen(sample.last_online_date, now)
+    : TEXT.offline;
 }
 
-function lastSeen(date: string): string {
-  return `last seen ${formatListDate(date)}`;
+export function formatSpan(seconds: number): string {
+  if (seconds < SECONDS_IN_MINUTE) {
+    return TEXT.seconds(Math.round(seconds));
+  }
+  const minutes = Math.round(seconds / SECONDS_IN_MINUTE);
+  if (minutes < MINUTES_IN_HOUR) {
+    return TEXT.minutes(minutes);
+  }
+  const hours = Math.floor(minutes / MINUTES_IN_HOUR);
+  const rest = minutes % MINUTES_IN_HOUR;
+  return rest === 0 ? TEXT.hours(hours) : TEXT.hoursMinutes(hours, rest);
+}
+
+export function formatClock(secondsOfDay: number): string {
+  const hours = Math.floor(secondsOfDay / SECONDS_IN_HOUR);
+  const minutes = Math.floor(
+    (secondsOfDay % SECONDS_IN_HOUR) / SECONDS_IN_MINUTE
+  );
+  return `${String(hours).padStart(2, "0")}:${String(minutes).padStart(2, "0")}`;
+}
+
+export function formatLongSpan(seconds: number): string {
+  if (seconds < 2 * SECONDS_IN_DAY) {
+    return formatSpan(seconds);
+  }
+  const days = Math.floor(seconds / SECONDS_IN_DAY);
+  const hours = Math.round((seconds % SECONDS_IN_DAY) / SECONDS_IN_HOUR);
+  return hours === 0
+    ? TEXT.days(days)
+    : `${TEXT.days(days)} ${TEXT.hours(hours)}`;
 }

frontend/src/lib/format/read.ts

@@ -0,0 +1,104 @@
+import type {
+  MessageView,
+  ReaderView,
+  ReadInfo,
+  ReadOutcome,
+} from "#lib/api/types.js";
+import { formatTime } from "#lib/format/datetime.js";
+import { locale, t } from "#lib/i18n/locale.svelte.js";
+import type { MessageKey } from "#lib/i18n/messages.js";
+
+export type ReadLine =
+  | { kind: "readers"; readers: ReaderView[] }
+  | { icon: string; kind: "text"; muted: boolean; text: string };
+
+const REASONS: Partial<Record<ReadOutcome, MessageKey>> = {
+  chat_too_big: "read.reason.chat_too_big",
+  error: "read.reason.error",
+  flood: "read.reason.flood",
+  too_old: "read.reason.too_old",
+  unavailable: "read.reason.unavailable",
+  user_privacy: "read.reason.user_privacy",
+  your_privacy: "read.reason.your_privacy",
+};
+
+const dayFormatters = new Map<string, Intl.DateTimeFormat>();
+
+function dayLabel(date: Date, withYear: boolean): string {
+  const formatKey = `${locale.tag}:${withYear}`;
+  let formatter = dayFormatters.get(formatKey);
+  if (!formatter) {
+    formatter = new Intl.DateTimeFormat(locale.tag, {
+      day: "numeric",
+      month: "short",
+      year: withYear ? "numeric" : undefined,
+    });
+    dayFormatters.set(formatKey, formatter);
+  }
+  const parts = formatter.formatToParts(date);
+  const pick = (type: Intl.DateTimeFormatPartTypes) =>
+    parts.find((part) => part.type === type)?.value.replace(".", "");
+  return [pick("day"), pick("month"), pick("year")].filter(Boolean).join(" ");
+}
+
+export function readWhen(iso: string): string {
+  const date = new Date(iso);
+  const now = new Date();
+  const time = formatTime(iso);
+  if (date.toDateString() === now.toDateString()) {
+    return t("read.when.today", { time });
+  }
+  const yesterday = new Date(now);
+  yesterday.setDate(now.getDate() - 1);
+  if (date.toDateString() === yesterday.toDateString()) {
+    return t("read.when.yesterday", { time });
+  }
+  const withYear = date.getFullYear() !== now.getFullYear();
+  return t("read.when.day", { day: dayLabel(date, withYear), time });
+}
+
+function line(text: string, icon = "message-read", muted = false): ReadLine {
+  return { icon, kind: "text", muted, text };
+}
+
+export function readTitle(message: MessageView): string | undefined {
+  if (message.read_at) {
+    return t("read.at", { when: readWhen(message.read_at) });
+  }
+  return message.read ? t("read.done") : undefined;
+}
+
+export function readLine(
+  message: MessageView,
+  info: ReadInfo | null,
+  fetching: boolean
+): ReadLine | null {
+  if (info === null) {
+    const title = readTitle(message);
+    return title ? line(title) : null;
+  }
+  if (info.chat_kind === "group" && info.readers.length > 0) {
+    return { kind: "readers", readers: info.readers };
+  }
+  if (info.voice && info.listened_at) {
+    return line(
+      t("read.listened", { when: readWhen(info.listened_at) }),
+      "play-story"
+    );
+  }
+  const at = info.exact_at ?? info.observed_at;
+  if (at) {
+    return line(t("read.at", { when: readWhen(at) }));
+  }
+  if (info.read) {
+    return line(t("read.done"));
+  }
+  if (info.unread) {
+    return line(t("read.unread"), "check");
+  }
+  const reason = info.outcome ? REASONS[info.outcome] : undefined;
+  if (reason) {
+    return line(t(reason), "eye-crossed-outline", true);
+  }
+  return fetching ? line(t("read.pending"), "message-read", true) : null;
+}

frontend/src/lib/i18n/messages.ts

@@ -1,12 +1,14 @@
 import { account } from "#lib/i18n/messages/account.js";
 import { common } from "#lib/i18n/messages/common.js";
 import { menu } from "#lib/i18n/messages/menu.js";
+import { read } from "#lib/i18n/messages/read.js";
 import { settings } from "#lib/i18n/messages/settings.js";
 
 export const messages = {
   ...account,
   ...common,
   ...menu,
+  ...read,
   ...settings,
 };
 

frontend/src/lib/i18n/messages/read.ts

@@ -0,0 +1,49 @@
+import type { Messages } from "#lib/i18n/types.js";
+
+export const read = {
+  "read.at": { en: "Read {when}", ru: "Прочитано {when}" },
+  "read.done": { en: "Read", ru: "Прочитано" },
+  "read.listened": { en: "Listened {when}", ru: "Прослушано {when}" },
+  "read.pending": { en: "Read time", ru: "Время прочтения" },
+  "read.readers": { en: "Read by {count}", ru: "Прочитали: {count}" },
+  "read.readers.empty": {
+    en: "Nobody has read it yet",
+    ru: "Пока никто не прочитал",
+  },
+  "read.readers.title": { en: "Read by", ru: "Прочитали" },
+  "read.reason.chat_too_big": {
+    en: "The group has over 100 members",
+    ru: "В группе больше 100 участников",
+  },
+  "read.reason.error": {
+    en: "Telegram did not answer",
+    ru: "Telegram не ответил",
+  },
+  "read.reason.flood": {
+    en: "Telegram asked to wait",
+    ru: "Telegram попросил подождать",
+  },
+  "read.reason.too_old": {
+    en: "Telegram no longer keeps the time",
+    ru: "Telegram уже не хранит время",
+  },
+  "read.reason.unavailable": {
+    en: "Telegram cannot find the chat",
+    ru: "Telegram не находит чат",
+  },
+  "read.reason.user_privacy": {
+    en: "They hide their read time",
+    ru: "Собеседник скрывает время прочтения",
+  },
+  "read.reason.your_privacy": {
+    en: "You hide your read time",
+    ru: "Вы скрываете своё время прочтения",
+  },
+  "read.unread": { en: "Not read yet", ru: "Не прочитано" },
+  "read.when.day": { en: "{day} at {time}", ru: "{day} в {time}" },
+  "read.when.today": { en: "today at {time}", ru: "сегодня в {time}" },
+  "read.when.yesterday": {
+    en: "yesterday at {time}",
+    ru: "вчера в {time}",
+  },
+} satisfies Messages;

frontend/src/lib/stores/presence.svelte.ts

@@ -0,0 +1,73 @@
+import { getCurrentPresence } from "#lib/api/endpoints.js";
+import type { PresenceSample } from "#lib/api/types.js";
+import { events } from "#lib/stores/events.svelte.js";
+
+const CLOCK_INTERVAL = 30_000;
+
+function createPresence() {
+  let peerId: number | null = null;
+  let key: string | null = null;
+  let sample = $state<PresenceSample | null>(null);
+  let now = $state(Date.now());
+  let clock: ReturnType<typeof setInterval> | undefined;
+  let token = 0;
+
+  async function refresh() {
+    const id = peerId;
+    token += 1;
+    const current = token;
+    if (id === null) {
+      return;
+    }
+    try {
+      const next = await getCurrentPresence(id);
+      if (current === token) {
+        sample = next;
+        now = Date.now();
+      }
+    } catch {
+      if (current === token) {
+        sample = null;
+      }
+    }
+  }
+
+  events.subscribe((event) => {
+    if (event.type === "presence" && event.peer_id === peerId) {
+      token += 1;
+      ({ sample } = event);
+      now = Date.now();
+    }
+  });
+  events.onReconnect(() => {
+    refresh();
+  });
+
+  return {
+    follow(accountId: number | null, id: number | null) {
+      const next =
+        accountId === null || id === null ? null : `${accountId}:${id}`;
+      if (next === key) {
+        return;
+      }
+      key = next;
+      peerId = next === null ? null : id;
+      sample = null;
+      clearInterval(clock);
+      if (peerId !== null) {
+        clock = setInterval(() => {
+          now = Date.now();
+        }, CLOCK_INTERVAL);
+        refresh();
+      }
+    },
+    get now(): number {
+      return now;
+    },
+    get sample(): PresenceSample | null {
+      return sample;
+    },
+  };
+}
+
+export const presence = createPresence();

frontend/src/lib/stores/reads.svelte.ts

@@ -0,0 +1,77 @@
+import { getJob, getReadInfo, refreshReadInfo } from "#lib/api/endpoints.js";
+import type { ReadInfo } from "#lib/api/types.js";
+import { accounts } from "#lib/stores/accounts.svelte.js";
+
+const POLL_INTERVAL = 1000;
+const POLL_MAX = 20;
+
+export interface ReadEntry {
+  fetching: boolean;
+  info: ReadInfo;
+}
+
+function delay(ms: number): Promise<void> {
+  return new Promise((resolve) => {
+    setTimeout(resolve, ms);
+  });
+}
+
+async function waitForJob(jobId: number) {
+  for (let attempt = 0; attempt < POLL_MAX; attempt += 1) {
+    // biome-ignore lint/performance/noAwaitInLoops: polling waits between tries on purpose
+    await delay(POLL_INTERVAL);
+    const job = await getJob(jobId);
+    if (job.status !== "pending" && job.status !== "running") {
+      return;
+    }
+  }
+}
+
+function createReads() {
+  let entries = $state<Record<string, ReadEntry>>({});
+  const inflight = new Set<string>();
+
+  function key(chatId: number, messageId: number): string {
+    return `${accounts.selectedId}:${chatId}:${messageId}`;
+  }
+
+  async function load(entryKey: string, chatId: number, messageId: number) {
+    const info = await getReadInfo(chatId, messageId);
+    entries[entryKey] = { fetching: info.can_fetch, info };
+    if (!info.can_fetch) {
+      return;
+    }
+    try {
+      const { job_id } = await refreshReadInfo(chatId, messageId);
+      if (job_id !== null) {
+        await waitForJob(job_id);
+      }
+      entries[entryKey] = {
+        fetching: false,
+        info: await getReadInfo(chatId, messageId),
+      };
+    } finally {
+      entries[entryKey].fetching = false;
+    }
+  }
+
+  return {
+    get(chatId: number, messageId: number): ReadEntry | undefined {
+      return entries[key(chatId, messageId)];
+    },
+    open(chatId: number, messageId: number) {
+      const entryKey = key(chatId, messageId);
+      if (accounts.selectedId === null || inflight.has(entryKey)) {
+        return;
+      }
+      inflight.add(entryKey);
+      load(entryKey, chatId, messageId)
+        .catch(() => undefined)
+        .finally(() => {
+          inflight.delete(entryKey);
+        });
+    },
+  };
+}
+
+export const reads = createReads();

frontend/src/lib/stores/ui.svelte.ts

@@ -3,6 +3,7 @@ export type RightPanel =
   | "search"
   | "versions"
   | "reactions"
+  | "readers"
   | "callbacks"
   | "links"
   | "annotations"

frontend/src/routes/app/+layout.svelte

@@ -154,7 +154,7 @@
 
       #RightColumn {
         position: relative;
-        z-index: 1;
+        z-index: var(--z-right-column);
       }
 
       #MiddleColumn {