from fastapi import APIRouter, BackgroundTasks, Depends, Form, Request
from fastapi.responses import RedirectResponse
from fastapi.templating import Jinja2Templates
from sqlalchemy import select

from app.db import get_db
from app.models import GenreCandidate, GenreRun
from app.security.deps import require_auth
from app.services import genre_review_service

router = APIRouter(prefix="/genres", tags=["genres"])
templates = Jinja2Templates(directory="app/templates")


@router.get("")
async def genres_index(request: Request, user: dict = Depends(require_auth), db=Depends(get_db)):
    latest_run = db.execute(select(GenreRun).order_by(GenreRun.id.desc())).scalars().first()
    candidates = []
    if latest_run is not None:
        candidates = list(
            db.execute(
                select(GenreCandidate).where(GenreCandidate.genre_run_id == latest_run.id)
            ).scalars()
        )
    return templates.TemplateResponse(
        request, "genres/index.html", {"latest_run": latest_run, "candidates": candidates}
    )


@router.post("/scan")
async def scan(background: BackgroundTasks, user: dict = Depends(require_auth)):
    # Always force=True: matches the weekly scheduled run's own behavior
    # (see genre_review_service.run's docstring), so a preview accurately
    # shows what "Fix genres now" would actually do. Runs in the background;
    # the last-run table below fills in when it finishes.
    background.add_task(genre_review_service.run, apply=False, force=True, triggered_by="manual")
    return RedirectResponse(url="/genres?started=1", status_code=303)


@router.post("/apply")
async def apply(background: BackgroundTasks, user: dict = Depends(require_auth)):
    background.add_task(genre_review_service.run, apply=True, force=True, triggered_by="manual")
    return RedirectResponse(url="/genres?started=1", status_code=303)


@router.post("/lock")
async def lock(
    artist: str = Form(...),
    genre: str = Form(...),
    user: dict = Depends(require_auth),
):
    changed_by = user.get("email") or user.get("sub", "unknown")
    await genre_review_service.lock_artist_genre(artist, genre, changed_by)
    return RedirectResponse(url="/genres", status_code=303)