the-custodian/state-hub/api/routers/token_events.py

import uuid
from collections import defaultdict

from fastapi import APIRouter, Depends, HTTPException, Query, status
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from api.database import get_session
from api.models.managed_repo import ManagedRepo
from api.models.task import Task
from api.models.token_event import TokenEvent
from api.models.workstream import Workstream
from api.schemas.token_event import RepoTokenSummary, TokenEventCreate, TokenEventPatch, TokenEventRead, TokenSummary

router = APIRouter(prefix="/token-events", tags=["token-events"])


@router.post("/", response_model=TokenEventRead, status_code=status.HTTP_201_CREATED)
async def create_token_event(
    body: TokenEventCreate,
    session: AsyncSession = Depends(get_session),
) -> TokenEvent:
    data = body.model_dump()

    # Auto-populate workstream_id from task if not provided
    if data.get("task_id") and not data.get("workstream_id"):
        task = await session.get(Task, data["task_id"])
        if task:
            data["workstream_id"] = task.workstream_id

    # Auto-populate repo_id from workstream if not provided
    if data.get("workstream_id") and not data.get("repo_id"):
        ws = await session.get(Workstream, data["workstream_id"])
        if ws and ws.repo_id:
            data["repo_id"] = ws.repo_id

    event = TokenEvent(**data)
    session.add(event)
    await session.commit()
    await session.refresh(event)
    return event


@router.get("/summary/", response_model=TokenSummary)
async def get_token_summary(
    scope: str = Query(..., description="task|workstream|repo|commit|release|session"),
    id: str = Query(..., description="FK value or ref_id depending on scope"),
    session: AsyncSession = Depends(get_session),
) -> TokenSummary:
    q = select(TokenEvent)

    if scope == "task":
        try:
            uid = uuid.UUID(id)
        except ValueError:
            raise HTTPException(status_code=422, detail="id must be a valid UUID for scope=task")
        q = q.where(TokenEvent.task_id == uid)
    elif scope == "workstream":
        try:
            uid = uuid.UUID(id)
        except ValueError:
            raise HTTPException(status_code=422, detail="id must be a valid UUID for scope=workstream")
        q = q.where(TokenEvent.workstream_id == uid)
    elif scope == "repo":
        try:
            uid = uuid.UUID(id)
        except ValueError:
            raise HTTPException(status_code=422, detail="id must be a valid UUID for scope=repo")
        q = q.where(TokenEvent.repo_id == uid)
    elif scope in ("commit", "release", "session"):
        q = q.where(TokenEvent.ref_type == scope, TokenEvent.ref_id == id)
    else:
        raise HTTPException(status_code=422, detail=f"Unknown scope: {scope!r}")

    result = await session.execute(q)
    events = list(result.scalars().all())

    tokens_in = sum(e.tokens_in for e in events)
    tokens_out = sum(e.tokens_out for e in events)

    by_model: dict[str, int] = defaultdict(int)
    by_agent: dict[str, int] = defaultdict(int)
    for e in events:
        if e.model:
            by_model[e.model] += e.tokens_in + e.tokens_out
        if e.agent:
            by_agent[e.agent] += e.tokens_in + e.tokens_out

    return TokenSummary(
        scope=scope,
        scope_id=id,
        tokens_in=tokens_in,
        tokens_out=tokens_out,
        tokens_total=tokens_in + tokens_out,
        event_count=len(events),
        by_model=dict(by_model),
        by_agent=dict(by_agent),
    )


@router.get("/by-repo/", response_model=list[RepoTokenSummary])
async def get_tokens_by_repo(
    session: AsyncSession = Depends(get_session),
) -> list[RepoTokenSummary]:
    """Aggregate token consumption per repo, resolving via the full graph.

    Resolution order for each event:
      1. token_events.repo_id (direct)
      2. → workstreams.repo_id (via workstream_id)
      3. → task.workstream_id → workstreams.repo_id (via task_id)

    Only events that resolve to a repo are included.
    """
    # Fetch all events, workstreams, repos in three queries (avoids N+1)
    events_result = await session.execute(select(TokenEvent))
    events = list(events_result.scalars().all())

    ws_result = await session.execute(select(Workstream))
    ws_map: dict[uuid.UUID, Workstream] = {w.id: w for w in ws_result.scalars().all()}

    task_result = await session.execute(select(Task))
    task_map: dict[uuid.UUID, Task] = {t.id: t for t in task_result.scalars().all()}

    repo_result = await session.execute(select(ManagedRepo))
    repo_map: dict[uuid.UUID, ManagedRepo] = {r.id: r for r in repo_result.scalars().all()}

    def resolve_repo_id(e: TokenEvent) -> uuid.UUID | None:
        if e.repo_id:
            return e.repo_id
        ws_id = e.workstream_id
        if not ws_id and e.task_id and e.task_id in task_map:
            ws_id = task_map[e.task_id].workstream_id
        if ws_id and ws_id in ws_map:
            return ws_map[ws_id].repo_id
        return None

    groups: dict[uuid.UUID, dict] = {}
    for e in events:
        rid = resolve_repo_id(e)
        if not rid or rid not in repo_map:
            continue
        if rid not in groups:
            groups[rid] = {
                "repo_id": rid,
                "repo_slug": repo_map[rid].slug,
                "tokens_in": 0,
                "tokens_out": 0,
                "event_count": 0,
                "by_model": defaultdict(int),
                "by_note": defaultdict(int),
            }
        g = groups[rid]
        g["tokens_in"] += e.tokens_in
        g["tokens_out"] += e.tokens_out
        g["event_count"] += 1
        if e.model:
            g["by_model"][e.model] += e.tokens_in + e.tokens_out
        g["by_note"][e.note or "unknown"] += e.tokens_in + e.tokens_out

    return [
        RepoTokenSummary(
            **{k: (dict(v) if isinstance(v, defaultdict) else v) for k, v in g.items()},
            tokens_total=g["tokens_in"] + g["tokens_out"],
        )
        for g in sorted(groups.values(), key=lambda x: -(x["tokens_in"] + x["tokens_out"]))
    ]


@router.patch("/{event_id}", response_model=TokenEventRead)
async def patch_token_event(
    event_id: uuid.UUID,
    body: TokenEventPatch,
    session: AsyncSession = Depends(get_session),
) -> TokenEvent:
    event = await session.get(TokenEvent, event_id)
    if event is None:
        raise HTTPException(status_code=404, detail="Token event not found")
    for field, value in body.model_dump(exclude_none=True).items():
        setattr(event, field, value)
    await session.commit()
    await session.refresh(event)
    return event


@router.get("/{event_id}", response_model=TokenEventRead)
async def get_token_event(
    event_id: uuid.UUID,
    session: AsyncSession = Depends(get_session),
) -> TokenEvent:
    event = await session.get(TokenEvent, event_id)
    if event is None:
        raise HTTPException(status_code=404, detail="Token event not found")
    return event


@router.get("/", response_model=list[TokenEventRead])
async def list_token_events(
    task_id: uuid.UUID | None = None,
    workstream_id: uuid.UUID | None = None,
    repo_id: uuid.UUID | None = None,
    ref_type: str | None = None,
    ref_id: str | None = None,
    model: str | None = None,
    agent: str | None = None,
    note: str | None = None,
    limit: int = Query(100, le=1000),
    session: AsyncSession = Depends(get_session),
) -> list[TokenEvent]:
    q = select(TokenEvent)
    if task_id:
        q = q.where(TokenEvent.task_id == task_id)
    if workstream_id:
        q = q.where(TokenEvent.workstream_id == workstream_id)
    if repo_id:
        q = q.where(TokenEvent.repo_id == repo_id)
    if ref_type:
        q = q.where(TokenEvent.ref_type == ref_type)
    if ref_id:
        q = q.where(TokenEvent.ref_id == ref_id)
    if model:
        q = q.where(TokenEvent.model == model)
    if agent:
        q = q.where(TokenEvent.agent == agent)
    if note:
        q = q.where(TokenEvent.note == note)
    q = q.order_by(TokenEvent.created_at.desc()).limit(limit)
    result = await session.execute(q)
    return list(result.scalars().all())