from __future__ import annotations

from collections import Counter, defaultdict, deque
from datetime import datetime, timedelta, timezone
from typing import Annotated, Literal
from uuid import UUID

import httpx
from fastapi import Depends, FastAPI, File, Header, HTTPException, Query, Request, Response, UploadFile
from fastapi.middleware.cors import CORSMiddleware
from sqlalchemy import select
from sqlalchemy.orm import Session, joinedload

from .activity import activity_rows
from .database import get_session
from .config import settings
from .importer import ImportSourceError, import_records, normalize
from .models import Bait, BaitKind, CatchReport, Fish, ModerationEvent, ModerationStatus, OfficialRecordImport, SourceType, Spot, Waterbody
from .schemas import ActivityOut, AdminCatchReportOut, BaitOut, CatchOut, CatchReportCreate, CatchReportCreated, FishOut, ImportRunOut, ModerationUpdate, OfficialRecordOut, SpotOut, WaterbodyOut
from .storage import ScreenshotError, signed_screenshot_url, upload_screenshot


app = FastAPI(title="RF4 Spotter API", version="0.1.0")
app.add_middleware(CORSMiddleware, allow_origins=["http://localhost:4321"], allow_methods=["GET"], allow_headers=["*"])
Db = Annotated[Session, Depends(get_session)]
_submissions: dict[str, deque[datetime]] = defaultdict(deque)


@app.get("/health")
def health() -> dict[str, str]:
    return {"status": "ok"}


@app.get("/api/v1/fishes", response_model=list[FishOut])
def fishes(db: Db) -> list[Fish]:
    return list(db.scalars(select(Fish).order_by(Fish.name_ru)))


@app.get("/api/v1/waterbodies", response_model=list[WaterbodyOut])
def waterbodies(db: Db) -> list[Waterbody]:
    return list(db.scalars(select(Waterbody).order_by(Waterbody.name_ru)))


@app.get("/api/v1/baits", response_model=list[BaitOut])
def baits(db: Db) -> list[Bait]:
    return list(db.scalars(select(Bait).order_by(Bait.name)))


@app.get("/api/v1/activity", response_model=list[ActivityOut])
def activity(
    db: Db, hours: int = Query(24),
    waterbody: str | None = None, fish: str | None = None,
    method: str | None = None,
    sort: Literal["activity", "confidence", "freshness"] = "activity",
    limit: int = Query(20, ge=1, le=100), offset: int = Query(0, ge=0),
) -> list[ActivityOut]:
    if hours not in {6, 12, 24, 72}:
        raise HTTPException(status_code=422, detail="hours must be one of: 6, 12, 24, 72")
    rows = activity_rows(db, hours=hours, waterbody=waterbody, fish=fish, method=method)
    keys = {"activity": lambda r: r.activity_score, "confidence": lambda r: r.confidence_score, "freshness": lambda r: r.last_confirmed_at}
    rows.sort(key=keys[sort], reverse=True)
    return rows[offset:offset + limit]


def _spot_or_404(db: Session, spot_id: UUID) -> Spot:
    spot = db.scalar(select(Spot).options(joinedload(Spot.waterbody)).where(Spot.id == spot_id))
    if spot is None:
        raise HTTPException(status_code=404, detail="spot not found")
    return spot


@app.get("/api/v1/spots/{spot_id}", response_model=SpotOut)
def spot_detail(spot_id: UUID, db: Db) -> SpotOut:
    spot = _spot_or_404(db, spot_id)
    reports = list(db.scalars(select(CatchReport).options(joinedload(CatchReport.bait)).where(CatchReport.spot_id == spot.id, CatchReport.moderation_status == ModerationStatus.approved)))
    now = datetime.now(timezone.utc)
    def count_since(delta: timedelta) -> int:
        return sum(_aware(r.reported_at) >= now - delta for r in reports)
    bait_counts = Counter(r.bait.name for r in reports if r.bait)
    return SpotOut(id=spot.id, waterbody_slug=spot.waterbody.slug, waterbody=spot.waterbody.name_ru, x=spot.x, y=spot.y, description=spot.description, catches_24h=count_since(timedelta(hours=24)), catches_3d=count_since(timedelta(days=3)), catches_7d=count_since(timedelta(days=7)), top_baits=[name for name, _ in bait_counts.most_common(5)])


@app.get("/api/v1/spots/{spot_id}/catches", response_model=list[CatchOut])
def spot_catches(spot_id: UUID, db: Db, limit: int = Query(50, ge=1, le=100), offset: int = Query(0, ge=0)) -> list[CatchOut]:
    _spot_or_404(db, spot_id)
    reports = list(db.scalars(select(CatchReport).options(joinedload(CatchReport.fish), joinedload(CatchReport.bait)).where(CatchReport.spot_id == spot_id, CatchReport.moderation_status == ModerationStatus.approved).order_by(CatchReport.reported_at.desc()).offset(offset).limit(limit)))
    return [CatchOut(id=r.id, fish=r.fish.name_ru, weight_g=r.weight_g, bait=r.bait.name if r.bait else None, player_name=r.player_name, caught_at=r.caught_at, reported_at=r.reported_at, retrieve_method=r.retrieve_method, retrieve_speed=r.retrieve_speed) for r in reports]


@app.get("/api/v1/records", response_model=list[OfficialRecordOut])
def records(
    db: Db, fish: str | None = None, waterbody: str | None = None,
    category: str | None = None, limit: int = Query(50, ge=1, le=100),
    offset: int = Query(0, ge=0),
) -> list[OfficialRecordOut]:
    query = select(CatchReport).options(joinedload(CatchReport.fish), joinedload(CatchReport.waterbody), joinedload(CatchReport.bait)).where(CatchReport.source_type == SourceType.official_record)
    if fish:
        query = query.join(CatchReport.fish).where(Fish.slug == fish)
    if waterbody:
        query = query.join(CatchReport.waterbody).where(Waterbody.slug == waterbody)
    items = list(db.scalars(query.order_by(CatchReport.caught_at.desc(), CatchReport.weight_g.desc()).offset(offset).limit(limit)))
    if category:
        items = [item for item in items if (item.raw_payload or {}).get("category") == category]
    return [OfficialRecordOut(id=r.id, fish=r.fish.name_ru, weight_g=r.weight_g, waterbody=r.waterbody.name_ru, bait=r.bait.name if r.bait else None, player_name=r.player_name, record_date=r.caught_at, category=(r.raw_payload or {}).get("category"), region=(r.raw_payload or {}).get("region"), source_url=r.source_url) for r in items]


def _admin(authorization: Annotated[str | None, Header()] = None) -> str:
    if not authorization or authorization != f"Bearer {settings.admin_token}":
        raise HTTPException(status_code=401, detail="invalid admin token", headers={"WWW-Authenticate": "Bearer"})
    return "admin"


@app.get("/api/v1/imports", response_model=list[ImportRunOut])
def imports(db: Db, limit: int = Query(20, ge=1, le=100)) -> list[OfficialRecordImport]:
    return list(db.scalars(select(OfficialRecordImport).order_by(OfficialRecordImport.started_at.desc()).limit(limit)))


@app.get("/api/v1/admin/imports", response_model=list[ImportRunOut])
def admin_imports(
    db: Db,
    _: Annotated[str, Depends(_admin)],
    limit: int = Query(20, ge=1, le=100),
    offset: int = Query(0, ge=0),
) -> list[OfficialRecordImport]:
    query = select(OfficialRecordImport).order_by(
        OfficialRecordImport.started_at.desc(), OfficialRecordImport.id.desc()
    ).offset(offset).limit(limit)
    return list(db.scalars(query))


@app.post("/api/v1/admin/imports/official-records", response_model=ImportRunOut, status_code=201)
def admin_start_official_import(db: Db, _: Annotated[str, Depends(_admin)]) -> OfficialRecordImport:
    try:
        return import_records(
            db,
            url=settings.official_records_url,
            region=settings.official_records_region,
            category=settings.official_records_category,
        )
    except (ImportSourceError, httpx.HTTPError) as exc:
        raise HTTPException(status_code=502, detail=f"official records import failed: {exc}") from exc


@app.post("/api/v1/catch-reports", response_model=CatchReportCreated, status_code=201)
def create_catch_report(payload: CatchReportCreate, request: Request, db: Db) -> CatchReportCreated:
    if payload.website:
        raise HTTPException(status_code=400, detail="invalid submission")
    _check_rate_limit(request.client.host if request.client else "unknown")
    fish = db.scalar(select(Fish).where(Fish.slug == payload.fish_slug))
    waterbody = db.scalar(select(Waterbody).where(Waterbody.slug == payload.waterbody_slug))
    if fish is None or waterbody is None:
        raise HTTPException(status_code=422, detail="unknown fish or waterbody")
    spot = db.scalar(select(Spot).where(Spot.waterbody_id == waterbody.id, Spot.x == payload.x, Spot.y == payload.y))
    if spot is None:
        spot = Spot(waterbody=waterbody, x=payload.x, y=payload.y)
        db.add(spot)
    bait = None
    if payload.bait_name and payload.bait_name.strip():
        key = normalize(payload.bait_name)
        bait = db.scalar(select(Bait).where(Bait.normalized_name == key))
        if bait is None:
            bait = Bait(name=payload.bait_name.strip(), normalized_name=key, kind=BaitKind.unknown)
            db.add(bait)
    report = CatchReport(fish=fish, spot=spot, waterbody=waterbody, bait=bait, weight_g=payload.weight_g, fishing_method=payload.fishing_method, rig_type=payload.rig_type, retrieve_method=payload.retrieve_method, retrieve_speed=payload.retrieve_speed, caught_at=payload.caught_at, reported_at=datetime.now(timezone.utc), player_name=payload.player_name, source_type=SourceType.user, source_url=payload.source_url, source_confidence=60, moderation_status=ModerationStatus.pending, raw_payload={"comment": payload.comment} if payload.comment else None)
    db.add(report)
    db.commit()
    return CatchReportCreated(id=report.id, moderation_status=report.moderation_status.value)


@app.post("/api/v1/catch-reports/{report_id}/screenshot", status_code=204, response_class=Response)
def add_screenshot(report_id: UUID, db: Db, screenshot: UploadFile = File()) -> Response:
    report = db.get(CatchReport, report_id)
    if report is None or report.source_type != SourceType.user or report.moderation_status != ModerationStatus.pending:
        raise HTTPException(status_code=404, detail="pending catch report not found")
    if report.screenshot_key:
        raise HTTPException(status_code=409, detail="screenshot already uploaded")
    raw = screenshot.file.read(settings.screenshot_max_bytes + 1)
    try:
        report.screenshot_key = upload_screenshot(raw)
    except ScreenshotError as exc:
        raise HTTPException(status_code=422, detail=str(exc)) from exc
    db.commit()
    return Response(status_code=204)


@app.get("/api/v1/admin/catch-reports", response_model=list[AdminCatchReportOut])
def admin_reports(db: Db, _: Annotated[str, Depends(_admin)], status: ModerationStatus = ModerationStatus.pending, limit: int = Query(50, ge=1, le=100)) -> list[AdminCatchReportOut]:
    reports = list(db.scalars(select(CatchReport).options(joinedload(CatchReport.fish), joinedload(CatchReport.waterbody), joinedload(CatchReport.spot), joinedload(CatchReport.bait)).where(CatchReport.source_type == SourceType.user, CatchReport.moderation_status == status).order_by(CatchReport.reported_at).limit(limit)))
    return [AdminCatchReportOut(id=r.id, fish=r.fish.name_ru, waterbody=r.waterbody.name_ru, coordinates=f"{r.spot.x}:{r.spot.y}" if r.spot else "—", weight_g=r.weight_g, bait=r.bait.name if r.bait else None, player_name=r.player_name, reported_at=r.reported_at, moderation_status=r.moderation_status.value, comment=(r.raw_payload or {}).get("comment"), screenshot_url=signed_screenshot_url(r.screenshot_key) if r.screenshot_key else None) for r in reports]


@app.patch("/api/v1/admin/catch-reports/{report_id}", response_model=CatchReportCreated)
def moderate_report(report_id: UUID, payload: ModerationUpdate, db: Db, moderator: Annotated[str, Depends(_admin)]) -> CatchReportCreated:
    report = db.get(CatchReport, report_id)
    if report is None or report.source_type != SourceType.user:
        raise HTTPException(status_code=404, detail="catch report not found")
    previous = report.moderation_status
    report.moderation_status = ModerationStatus(payload.status)
    db.add(ModerationEvent(catch_report=report, created_at=datetime.now(timezone.utc), previous_status=previous, new_status=report.moderation_status, moderator=moderator, reason=payload.reason))
    db.commit()
    return CatchReportCreated(id=report.id, moderation_status=report.moderation_status.value)


def _check_rate_limit(client: str) -> None:
    now = datetime.now(timezone.utc)
    recent = _submissions[client]
    while recent and recent[0] < now - timedelta(minutes=10):
        recent.popleft()
    if len(recent) >= 5:
        raise HTTPException(status_code=429, detail="too many submissions")
    recent.append(now)


def _aware(value: datetime) -> datetime:
    return value if value.tzinfo else value.replace(tzinfo=timezone.utc)