"""Agent / MCP registries + the user-facing ``Gateway`` collector.

The user's ``/config/config.py`` ends with::

    gateway = Gateway(agents=[...], mcps=[...], frontends=[...])

``cli.main`` picks that object up and builds the registries.
"""

from __future__ import annotations

from dataclasses import dataclass, field
from typing import TYPE_CHECKING

if TYPE_CHECKING:
    from collections.abc import Awaitable, Callable, Iterable, Iterator

    from beaver_gateway.agents.base import BaseAgent
    from beaver_gateway.core.conversations import ConversationTexts, UserSaid
    from beaver_gateway.core.distill import Distiller
    from beaver_gateway.core.envelope import RecallContext
    from beaver_gateway.core.rotation import RotationPolicy
    from beaver_gateway.core.scheduler import Budget, Job
    from beaver_gateway.core.watch import VaultWatch
    from beaver_gateway.frontends.base import Frontend
    from beaver_gateway.mcp.types import McpServerT


class AgentRegistry:
    """Name → agent lookup with duplicate detection."""

    def __init__(self, agents: Iterable[BaseAgent]) -> None:
        self._agents: dict[str, BaseAgent] = {}
        for a in agents:
            if a.name in self._agents:
                msg = f"duplicate agent name: {a.name!r}"
                raise ValueError(msg)
            self._agents[a.name] = a

    def __getitem__(self, name: str) -> BaseAgent:
        return self._agents[name]

    def get(self, name: str) -> BaseAgent | None:
        return self._agents.get(name)

    def __iter__(self) -> Iterator[BaseAgent]:
        return iter(self._agents.values())

    def __len__(self) -> int:
        return len(self._agents)

    def __contains__(self, name: object) -> bool:
        return name in self._agents


class McpRegistry:
    """Name → MCP server lookup with duplicate detection."""

    def __init__(self, mcps: Iterable[McpServerT]) -> None:
        self._mcps: dict[str, McpServerT] = {}
        for m in mcps:
            if m.name in self._mcps:
                msg = f"duplicate mcp name: {m.name!r}"
                raise ValueError(msg)
            self._mcps[m.name] = m

    def __getitem__(self, name: str) -> McpServerT:
        return self._mcps[name]

    def get(self, name: str) -> McpServerT | None:
        return self._mcps.get(name)

    def __iter__(self) -> Iterator[McpServerT]:
        return iter(self._mcps.values())

    def __len__(self) -> int:
        return len(self._mcps)

    def __contains__(self, name: object) -> bool:
        return name in self._mcps


@dataclass(slots=True)
class Gateway:
    """Top-level object the user assembles in ``/config/config.py``."""

    agents: list[BaseAgent] = field(default_factory=list)
    mcps: list[McpServerT] = field(default_factory=list)
    frontends: list[Frontend] = field(default_factory=list)
    texts: ConversationTexts | None = None
    """Merge prompt and seed bodies for ``core/conversations`` (§8.2-8.3)."""
    jobs: list[Job] = field(default_factory=list)
    """Cron / webhook / event jobs for ``core/scheduler`` (§3.6, §4.5)."""
    rotation: RotationPolicy | None = None
    """When a master is rotated (§4.5); ``None`` keeps the defaults."""
    watch: VaultWatch | None = None
    """Vault watcher feeding the envelope (§3.5, §4.6); ``None`` = no vault block."""
    recall: Callable[[RecallContext], str | None] | None = None
    """Envelope lookup on the user's text: pointers into the vault (cards,
    the agent's notes, due dates) the gateway knows no paths for (§3.3)."""
    user_sink: Callable[[UserSaid], Awaitable[None] | None] | None = None
    """Sees every user message as it enters a master or branch turn - the
    setup's own grep-able log of what the user said, outside the transcript."""
    budget: Budget | None = None
    """Subscription window past which non-critical jobs wait (§4.5)."""
    distiller: Distiller | None = None
    """Who closes deep chats and where the digests and the index live (§8.4)."""
    tz: str = "UTC"
    """Local zone for the envelope clock and the rotation hour."""
    host: str = "0.0.0.0"  # noqa: S104
    port: int = 8000
    """The one listener; every HTTP frontend is mounted under its ``path``."""
    public_url: str | None = None
    """Origin the reverse proxy shows the world (``https://b.example.com``).

    Advertised endpoints and MCP discovery are built on it; ``None``
    derives the origin from each request."""