fix(api,frontend): render files by name without fetching, previewable share links

backend/src/api/routers/files.py

@@ -6,7 +6,12 @@ from dishka.integrations.fastapi import DishkaRoute, FromDishka
 from fastapi import APIRouter, Query, Request
 from fastapi.responses import FileResponse, PlainTextResponse
 
-from utils.files import content_disposition, counts_as_download, is_inline_mime
+from utils.files import (
+    content_disposition,
+    counts_as_download,
+    is_inline_mime,
+    resolve_mime,
+)
 from utils.read import shares
 from utils.storage import ContentAddressedStorage
 
@@ -35,13 +40,13 @@ def _exhausted(row: asyncpg.Record) -> bool:
     return limit is not None and row["download_count"] >= limit
 
 
-@router.api_route("/f/{token}", methods=["GET", "HEAD"], response_model=None)
-async def serve_shared_file(
+async def _serve(
     request: Request,
-    pool: FromDishka[asyncpg.Pool],
-    storage: FromDishka[ContentAddressedStorage],
+    pool: asyncpg.Pool,
+    storage: ContentAddressedStorage,
     token: str,
-    dl: Annotated[bool, Query()] = False,
+    *,
+    dl: bool,
 ) -> FileResponse | PlainTextResponse:
     row = await shares.share_by_token(pool, token)
     if row is None:
@@ -64,8 +69,8 @@ async def serve_shared_file(
         return PlainTextResponse(_GONE, status_code=410, headers=_NO_STORE)
 
     await shares.record_hit(pool, row["id"], method, ip, agent, counted=counts)
-    mime = row["mime"] or "application/octet-stream"
-    attachment = dl or not is_inline_mime(row["mime"])
+    mime = resolve_mime(row["kind"], row["mime"], row["file_name"])
+    attachment = dl or not is_inline_mime(mime)
     return FileResponse(
         storage.url(row["storage_key"]),
         media_type=mime,
@@ -76,3 +81,26 @@ async def serve_shared_file(
             ),
         },
     )
+
+
+@router.api_route("/f/{token}", methods=["GET", "HEAD"], response_model=None)
+async def serve_shared_file(
+    request: Request,
+    pool: FromDishka[asyncpg.Pool],
+    storage: FromDishka[ContentAddressedStorage],
+    token: str,
+    dl: Annotated[bool, Query()] = False,
+) -> FileResponse | PlainTextResponse:
+    return await _serve(request, pool, storage, token, dl=dl)
+
+
+@router.api_route("/f/{token}/{name}", methods=["GET", "HEAD"], response_model=None)
+async def serve_shared_file_named(
+    request: Request,
+    pool: FromDishka[asyncpg.Pool],
+    storage: FromDishka[ContentAddressedStorage],
+    token: str,
+    name: str,  # noqa: ARG001
+    dl: Annotated[bool, Query()] = False,
+) -> FileResponse | PlainTextResponse:
+    return await _serve(request, pool, storage, token, dl=dl)

backend/src/api/routers/media.py

@@ -6,7 +6,7 @@ from fastapi import APIRouter, HTTPException, Query
 from fastapi.responses import FileResponse
 
 from utils.cache import DAY_HEADERS, IMMUTABLE_HEADERS
-from utils.files import content_disposition, media_file_name
+from utils.files import content_disposition, media_file_name, resolve_mime
 from utils.read.media import (
     get_media,
     get_media_version,
@@ -63,7 +63,7 @@ async def serve_media_version(
         )
     return FileResponse(
         storage.url(version.storage_key),
-        media_type=version.mime or "application/octet-stream",
+        media_type=resolve_mime(version.kind, version.mime),
         headers=headers,
     )
 
@@ -101,6 +101,6 @@ async def serve_media(
         headers = _attachment(headers, media.file_name or f"media_{media_id}")
     return FileResponse(
         storage.url(media.storage_key),
-        media_type=media.mime or "application/octet-stream",
+        media_type=resolve_mime(media.kind, media.mime, media.file_name),
         headers=headers,
     )

backend/src/api/routers/shares.py

@@ -5,7 +5,12 @@ from dishka.integrations.fastapi import DishkaRoute, FromDishka
 from fastapi import APIRouter, HTTPException, Query
 from pydantic import BaseModel
 
-from utils.files import expiry_from_seconds, media_file_name, story_file_name
+from utils.files import (
+    expiry_from_seconds,
+    media_file_name,
+    resolve_mime,
+    story_file_name,
+)
 from utils.read import chats, peers, shares
 from utils.read.media import get_media, get_media_version
 from utils.read.models import DEFAULT_LIMIT, FileShareHitView, FileShareView, Page
@@ -56,10 +61,11 @@ async def _media_subject(pool: asyncpg.Pool, media_id: int) -> Subject:
         raise HTTPException(status_code=404, detail="media not found")
     if not media.downloaded or media.storage_key is None:
         raise HTTPException(status_code=409, detail=_NOT_STORED)
+    file_name = media.file_name or f"media_{media.id}"
     return Subject(
         storage_key=media.storage_key,
-        file_name=media.file_name or f"media_{media.id}",
-        mime=media.mime,
+        file_name=file_name,
+        mime=resolve_mime(media.kind, media.mime, file_name),
         file_size=media.file_size,
         title=await _chat_title(pool, media.account_id, media.chat_id),
         chat_id=media.chat_id,
@@ -71,10 +77,11 @@ async def _version_subject(pool: asyncpg.Pool, version_id: int) -> Subject:
     version = await get_media_version(pool, version_id)
     if version is None:
         raise HTTPException(status_code=404, detail="media version not found")
+    version_name = media_file_name(version.kind, version.mime, version_id)
     return Subject(
         storage_key=version.storage_key,
-        file_name=media_file_name(version.kind, version.mime, version_id),
-        mime=version.mime,
+        file_name=version_name,
+        mime=resolve_mime(version.kind, version.mime, version_name),
         file_size=version.file_size,
         title=None,
         chat_id=None,

backend/src/utils/files.py

@@ -29,6 +29,42 @@ _KIND_EXTENSIONS = {
     "voice": ".ogg",
 }
 
+_EXTENSION_MIMES = {
+    ".flac": "audio/flac",
+    ".gif": "image/gif",
+    ".heic": "image/heic",
+    ".jpeg": "image/jpeg",
+    ".jpg": "image/jpeg",
+    ".m4a": "audio/mp4",
+    ".mov": "video/quicktime",
+    ".mp3": "audio/mpeg",
+    ".mp4": "video/mp4",
+    ".ogg": "audio/ogg",
+    ".pdf": "application/pdf",
+    ".png": "image/png",
+    ".svg": "image/svg+xml",
+    ".txt": "text/plain",
+    ".wav": "audio/wav",
+    ".webm": "video/webm",
+    ".webp": "image/webp",
+}
+
+_KIND_MIMES = {
+    "animation": "video/mp4",
+    "gif": "video/mp4",
+    "photo": "image/jpeg",
+    "video": "video/mp4",
+    "video_note": "video/mp4",
+    "voice": "audio/ogg",
+}
+
+_GENERIC_MIMES = {
+    "application/octet-stream",
+    "application/binary",
+    "binary/octet-stream",
+    "",
+}
+
 _INLINE_MIME_PREFIXES = ("image/", "video/", "audio/", "text/")
 _INLINE_MIMES = {"application/pdf", "application/json"}
 
@@ -57,6 +93,45 @@ _PREVIEW_AGENTS = (
     "python-requests",
 )
 
+_TRANSLIT = {
+    "а": "a",
+    "б": "b",
+    "в": "v",
+    "г": "g",
+    "д": "d",
+    "е": "e",
+    "ё": "e",
+    "ж": "zh",
+    "з": "z",
+    "и": "i",
+    "й": "y",
+    "к": "k",
+    "л": "l",
+    "м": "m",
+    "н": "n",
+    "о": "o",
+    "п": "p",
+    "р": "r",
+    "с": "s",
+    "т": "t",
+    "у": "u",
+    "ф": "f",
+    "х": "h",
+    "ц": "c",
+    "ч": "ch",
+    "ш": "sh",
+    "щ": "sch",
+    "ъ": "",
+    "ы": "y",
+    "ь": "",
+    "э": "e",
+    "ю": "yu",
+    "я": "ya",
+}
+
+_URL_UNSAFE = re.compile(r"[^A-Za-z0-9._-]+")
+_URL_REPEATS = re.compile(r"_{2,}")
+
 _UNSAFE_CHARS = re.compile(r'[\\/:*?"<>|\x00-\x1f]+')
 _SPACES = re.compile(r"\s+")
 _NAME_LIMIT = 120
@@ -86,6 +161,16 @@ def sanitize_name(name: str) -> str:
     return cleaned or "file"
 
 
+def url_slug(file_name: str) -> str:
+    lowered = "".join(
+        _TRANSLIT.get(ch, _TRANSLIT.get(ch.lower(), ch)) for ch in file_name
+    )
+    slug = _URL_REPEATS.sub("_", _URL_UNSAFE.sub("_", lowered)).strip("_.")
+    if not slug:
+        return "file"
+    return slug[:_NAME_LIMIT]
+
+
 def media_file_name(
     kind: str | None, mime: str | None, message_id: int, original: str | None = None
 ) -> str:
@@ -99,6 +184,18 @@ def story_file_name(peer_id: int, story_id: int, media_kind: str | None) -> str:
     return f"story_{peer_id}_{story_id}{extension_for(media_kind or 'photo', None)}"
 
 
+def resolve_mime(
+    kind: str | None, mime: str | None, file_name: str | None = None
+) -> str:
+    if mime and mime.lower() not in _GENERIC_MIMES:
+        return mime
+    if file_name and "." in file_name:
+        by_extension = _EXTENSION_MIMES.get(f".{file_name.rsplit('.', 1)[1].lower()}")
+        if by_extension:
+            return by_extension
+    return _KIND_MIMES.get(kind or "", mime or "application/octet-stream")
+
+
 def is_inline_mime(mime: str | None) -> bool:
     if not mime:
         return False

backend/src/utils/read/models.py

@@ -401,6 +401,7 @@ class FileShareView(BaseModel):
     token: str
     kind: str
     file_name: str
+    url_name: str
     mime: str | None
     file_size: int | None
     title: str | None

backend/src/utils/read/shares.py

@@ -3,6 +3,7 @@ from datetime import datetime
 
 import asyncpg
 
+from utils.files import url_slug
 from utils.read.models import FileShareHitView, FileShareView, Page
 
 _COLS = (
@@ -11,10 +12,11 @@ _COLS = (
     "download_count, last_download_at, revoked_at, created_at"
 )
 
-_TOKEN_BYTES = 12
+_TOKEN_ALPHABET = "abcdefghijkmnpqrstuvwxyz23456789"  # noqa: S105
+_TOKEN_LENGTH = 10
 
 _SERVE = """
-SELECT id, storage_key, file_name, mime, expires_at, max_downloads,
+SELECT id, kind, storage_key, file_name, mime, expires_at, max_downloads,
        download_count, revoked_at
 FROM file_shares WHERE token = $1
 """
@@ -45,11 +47,12 @@ RETURNING download_count
 
 
 def new_token() -> str:
-    return secrets.token_urlsafe(_TOKEN_BYTES)
+    return "".join(secrets.choice(_TOKEN_ALPHABET) for _ in range(_TOKEN_LENGTH))
 
 
 def _view(row: asyncpg.Record) -> FileShareView:
-    return FileShareView(**dict(row))
+    fields = dict(row)
+    return FileShareView(**fields, url_name=url_slug(fields["file_name"]))
 
 
 async def list_shares(

frontend/src/lib/api/media.ts

@@ -21,9 +21,11 @@ export type InlineMedia =
 export interface ViewerItem {
   downloaded: boolean;
   fileName: string | null;
+  fileSize: number | null;
   kind: string;
   mediaId: number | null;
   messageId: number;
+  mime: string | null;
 }
 
 export function viewerItemsFrom(
@@ -32,7 +34,15 @@ export function viewerItemsFrom(
 ): ViewerItem[] {
   if (media.length === 0) {
     return [
-      { messageId, mediaId: null, kind: "", downloaded: false, fileName: null },
+      {
+        messageId,
+        mediaId: null,
+        kind: "",
+        downloaded: false,
+        fileName: null,
+        fileSize: null,
+        mime: null,
+      },
     ];
   }
   return media.map((item) => ({
@@ -41,9 +51,31 @@ export function viewerItemsFrom(
     kind: item.kind,
     downloaded: item.downloaded,
     fileName: item.file_name,
+    fileSize: item.file_size,
+    mime: item.mime,
   }));
 }
 
+const PREVIEW_KINDS = new Set([
+  "photo",
+  "video",
+  "video_note",
+  "animation",
+  "gif",
+  "sticker",
+  "voice",
+  "audio",
+]);
+
+const PREVIEW_MIME_PREFIXES = ["image/", "video/", "audio/"];
+
+export function isPreviewable(kind: string, mime: string | null): boolean {
+  if (PREVIEW_KINDS.has(kind)) {
+    return true;
+  }
+  return PREVIEW_MIME_PREFIXES.some((prefix) => mime?.startsWith(prefix));
+}
+
 export type VisualKind = "image" | "video" | "other";
 
 const VIDEO_KINDS = new Set(["video", "video_note", "animation", "gif"]);

frontend/src/lib/api/shares.ts

@@ -97,7 +97,7 @@ export function shareUrl(share: FileShare): string {
     typeof window === "undefined"
       ? ""
       : window.location.origin.replace(TRAILING_SLASH, "");
-  return `${origin}/f/${share.token}`;
+  return `${origin}/f/${share.token}/${share.url_name}`;
 }
 
 export function shareState(

frontend/src/lib/api/types.ts

@@ -528,6 +528,7 @@ export interface FileShare {
   story_id: number | null;
   title: string | null;
   token: string;
+  url_name: string;
 }
 
 export interface FileShareHit {

frontend/src/lib/components/MediaViewer.svelte

@@ -4,13 +4,13 @@
   import { type MediaResult, requestMedia } from "$lib/api/client";
   import { downloadMedia } from "$lib/api/download";
   import { fetchMedia, getMessageMedia } from "$lib/api/endpoints";
-  import type { ViewerItem } from "$lib/api/media";
+  import { isPreviewable, type ViewerItem } from "$lib/api/media";
   import Button from "$lib/components/ui/Button.svelte";
   import ContextMenu from "$lib/components/ui/ContextMenu.svelte";
   import ContextMenuItem from "$lib/components/ui/ContextMenuItem.svelte";
   import Icon from "$lib/components/ui/Icon.svelte";
   import Spinner from "$lib/components/ui/Spinner.svelte";
-  import { mediaKindLabel } from "$lib/format/media";
+  import { formatBytes, mediaKindLabel } from "$lib/format/media";
   import { poster } from "$lib/media/poster";
   import { shareUi } from "$lib/stores/shares.svelte";
   import { toasts } from "$lib/stores/toasts.svelte";
@@ -33,6 +33,8 @@
   let messageId = $state<number | null>(null);
   let currentMediaId = $state<number | null>(null);
   let fileName = $state<string | null>(null);
+  let fileSize = $state<number | null>(null);
+  let fileOnly = $state(false);
   let result = $state<MediaResult | null>(null);
   let loading = $state(false);
   let saving = $state(false);
@@ -48,12 +50,12 @@
   );
   const hasNav = $derived(items.length > 1);
   const canSave = $derived(
-    currentMediaId !== null && result?.state === "ready"
+    currentMediaId !== null && (fileOnly || result?.state === "ready")
   );
   const title = $derived(fileName ?? mediaKindLabel(kind) ?? "Медиа");
 
   function revoke() {
-    if (result?.state === "ready") {
+    if (result?.state === "ready" && result.url) {
       URL.revokeObjectURL(result.url);
     }
   }
@@ -66,25 +68,39 @@
     messageId = item.messageId;
     currentMediaId = null;
     fileName = item.fileName;
+    fileSize = item.fileSize;
+    fileOnly = false;
     const current = ++token;
     try {
       let mediaId = item.mediaId;
       let downloaded = item.downloaded;
       let name = item.fileName;
+      let size = item.fileSize;
+      let mimeType = item.mime;
       if (mediaId === null) {
         const meta = await getMessageMedia(chatId, item.messageId);
         mediaId = meta.id;
         downloaded = meta.downloaded;
         kind = meta.kind;
         name = meta.file_name;
+        size = meta.file_size;
+        mimeType = meta.mime;
+      }
+      const plainFile = downloaded && !isPreviewable(kind, mimeType);
+      let next: MediaResult;
+      if (plainFile) {
+        next = { state: "ready", url: "", mime: mimeType };
+      } else if (downloaded) {
+        next = await requestMedia(mediaId);
+      } else {
+        next = { state: "not-downloaded" } as MediaResult;
       }
-      const next = downloaded
-        ? await requestMedia(mediaId)
-        : ({ state: "not-downloaded" } as MediaResult);
       if (current === token) {
         result = next;
         currentMediaId = mediaId;
         fileName = name;
+        fileSize = size;
+        fileOnly = plainFile;
       }
     } catch {
       if (current === token) {
@@ -233,10 +249,17 @@
           <!-- biome-ignore lint/a11y/useMediaCaption: archived media has no captions -->
           <audio src={result.url} controls></audio>
         {:else if result?.state === "ready"}
+          <div class="media-file">
+            <span class="file-glyph"><Icon name="document" size="2rem" /></span>
+            <p class="file-name">{title}</p>
+            {#if fileSize}
+              <p class="file-size">{formatBytes(fileSize)}</p>
+            {/if}
             <button class="media-download" type="button" onclick={save}>
               <Icon name="download" />
               Скачать файл
             </button>
+          </div>
         {:else if result?.state === "not-downloaded"}
           <div class="media-message">
             <p>Файл ещё не скачан в архив.</p>
@@ -354,6 +377,42 @@
     text-align: center;
   }
 
+  .media-file {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    gap: 0.25rem;
+
+    max-width: min(24rem, 90vw);
+    color: var(--color-white);
+    text-align: center;
+  }
+
+  .file-glyph {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+
+    width: 4.5rem;
+    height: 4.5rem;
+    margin-bottom: 0.5rem;
+    border-radius: 50%;
+
+    background-color: rgba(255, 255, 255, 0.12);
+  }
+
+  .file-name {
+    overflow-wrap: anywhere;
+    margin: 0;
+    font-size: 1rem;
+  }
+
+  .file-size {
+    margin: 0 0 0.75rem;
+    font-size: 0.8125rem;
+    color: rgba(255, 255, 255, 0.6);
+  }
+
   .media-download {
     display: inline-flex;
     align-items: center;

frontend/src/lib/components/MessageMedia.svelte

@@ -4,6 +4,7 @@
   import { fetchMedia } from "$lib/api/endpoints";
   import {
     type InlineMedia,
+    isPreviewable,
     loadInlineMedia,
     visualKind,
   } from "$lib/api/media";
@@ -16,7 +17,7 @@
   import ContextMenuItem from "$lib/components/ui/ContextMenuItem.svelte";
   import Icon from "$lib/components/ui/Icon.svelte";
   import Spinner from "$lib/components/ui/Spinner.svelte";
-  import { mediaKindLabel } from "$lib/format/media";
+  import { formatBytes, mediaKindLabel } from "$lib/format/media";
   import { poster } from "$lib/media/poster";
   import { shareUi } from "$lib/stores/shares.svelte";
   import { toasts } from "$lib/stores/toasts.svelte";
@@ -38,8 +39,13 @@
   let queuing = $state(false);
   let saving = $state(false);
 
+  const ref = $derived(message.media[0] ?? null);
+  const asFile = $derived(
+    ref !== null && ref.id !== null && !isPreviewable(ref.kind, ref.mime)
+  );
+
   const ready = $derived(media?.state === "ready" ? media : null);
-  const kind = $derived(ready?.kind ?? "");
+  const kind = $derived(ready?.kind ?? ref?.kind ?? "");
   const mime = $derived(ready?.mime ?? "");
   const isImage = $derived(kind === "photo");
   const isStaticSticker = $derived(
@@ -60,7 +66,10 @@
   const label = $derived(
     media && media.state !== "missing" ? media.kind : "media"
   );
-  const storedId = $derived(ready?.mediaId ?? null);
+  const storedId = $derived(
+    ready?.mediaId ?? (asFile ? ref?.id : null) ?? null
+  );
+  const fileName = $derived(ref?.file_name ?? mediaKindLabel(kind) ?? "Файл");
 
   function delay(ms: number): Promise<void> {
     return new Promise((resolve) => {
@@ -69,6 +78,10 @@
   }
 
   async function start() {
+    if (asFile) {
+      loaded = true;
+      return;
+    }
     media = await loadInlineMedia(message.chat_id, message.message_id);
     loaded = true;
   }
@@ -116,10 +129,7 @@
 
   function share() {
     if (storedId !== null) {
-      shareUi.share(
-        { kind: "media", mediaId: storedId },
-        mediaKindLabel(kind) ?? "Файл"
-      );
+      shareUi.share({ kind: "media", mediaId: storedId }, fileName);
     }
   }
 </script>
@@ -132,6 +142,18 @@
           <Icon name="timer" size="1.25rem" />
           <span>Самоуничтожающееся медиа</span>
         </button>
+      {:else if asFile}
+        <button class="media-file" onclick={save} type="button">
+          <span class="file-glyph">
+            <Icon name={saving ? "timer" : "document"} size="1.25rem" />
+          </span>
+          <span class="file-text">
+            <span class="file-name">{fileName}</span>
+            <span class="file-sub">
+              {formatBytes(ref?.file_size ?? null) || mediaKindLabel(kind)}
+            </span>
+          </span>
+        </button>
       {:else if !loaded}
         <div class="media-skeleton"><Spinner /></div>
       {:else if ready && kind === "voice"}
@@ -145,7 +167,7 @@
       {:else if ready && kind === "video_note"}
         <VideoNote url={ready.url} transcript={ready.transcript} />
       {:else if ready && kind === "audio"}
-        <AudioFile url={ready.url} title={ready.mime ?? "Audio"} {own} />
+        <AudioFile url={ready.url} title={fileName} {own} />
       {:else if ready && isImage}
         <button class="media-thumb" onclick={onopen} type="button">
           <img src={ready.url} alt="attachment">
@@ -348,6 +370,58 @@
     }
   }
 
+  .media-file {
+    cursor: pointer;
+
+    display: flex;
+    align-items: center;
+    gap: 0.625rem;
+
+    width: 100%;
+    max-width: 18rem;
+    padding: 0.5rem 0.75rem 0.5rem 0.5rem;
+    border: 0;
+    border-radius: var(--border-radius-default-small);
+
+    text-align: start;
+
+    background-color: var(--color-primary-tint);
+  }
+
+  .file-glyph {
+    display: flex;
+    flex-shrink: 0;
+    align-items: center;
+    justify-content: center;
+
+    width: 2.25rem;
+    height: 2.25rem;
+    border-radius: 50%;
+
+    color: var(--color-white);
+    background-color: var(--color-primary);
+  }
+
+  .file-text {
+    display: flex;
+    flex-direction: column;
+    min-width: 0;
+  }
+
+  .file-name {
+    overflow: hidden;
+
+    font-size: 0.9375rem;
+    color: var(--color-text);
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+
+  .file-sub {
+    font-size: 0.75rem;
+    color: var(--color-text-secondary);
+  }
+
   .media-chip {
     cursor: pointer;
     display: flex;

frontend/src/lib/components/profile/SharedMedia.svelte

@@ -50,6 +50,8 @@
       kind: item.kind,
       downloaded: item.downloaded,
       fileName: item.file_name,
+      fileSize: item.file_size,
+      mime: item.mime,
     }))
   );
 

frontend/src/lib/components/shares/ShareDialog.svelte

@@ -212,10 +212,9 @@
           {/if}
 
           <p class="hint raw">
-            Ссылка отдаёт файл как есть —
-            <code>curl -O {shareUrl(share)}</code>
-            скачает его без авторизации. Просмотры превью в Telegram не
-            списывают скачивания.
+            Ссылка отдаёт файл как есть: картинки и видео откроются прямо в
+            браузере, <code>curl -O {shareUrl(share)}</code> скачает под
+            настоящим именем. Превью-краулеры Telegram скачивания не списывают.
           </p>
 
           <fieldset class="choices">