from datetime import datetime, timedelta, timezone

from fastapi import APIRouter, HTTPException, Query
from sqlalchemy import func, or_, select
from sqlalchemy.orm import joinedload

from ..config import settings
from ..dependencies import Db
from ..models import (
    CatchReport,
    Bait,
    CommunityImportRun,
    DataSource,
    ExternalObservation,
    Fish,
    OfficialRecordImport,
    SourceType,
    Waterbody,
)
from ..schemas import (
    ImportRunPublicOut,
    OfficialRecordOut,
    PaginatedOfficialRecordOut,
    PublicObservationOut,
    SourceStatusOut,
)
from ..time_utils import aware

router = APIRouter()


@router.get("/api/v1/community-observations", response_model=list[PublicObservationOut])
def community_observations(
    db: Db,
    limit: int = Query(12, ge=1, le=50),
    offset: int = Query(0, ge=0),
    waterbody: str | None = None,
    fish: str | None = None,
) -> list[PublicObservationOut]:
    query = select(ExternalObservation).join(ExternalObservation.source).options(
        joinedload(ExternalObservation.source)
    ).where(
        ExternalObservation.catch_report_id.is_(None),
        ExternalObservation.status.not_in(["rejected", "withdrawn"]),
        DataSource.enabled.is_(True),
    )
    if waterbody:
        query = query.join(ExternalObservation.waterbody).where(Waterbody.slug == waterbody)
    if fish:
        query = query.join(ExternalObservation.fish).where(Fish.slug == fish)
    items = list(db.scalars(
        query.order_by(ExternalObservation.last_seen_at.desc(), ExternalObservation.id.desc())
        .offset(offset).limit(limit)
    ))
    result: list[PublicObservationOut] = []
    for item in items:
        missing = []
        if item.x is None or item.y is None:
            missing.append("координаты")
        if item.weight_g is None:
            missing.append("вес")
        result.append(PublicObservationOut(
            id=item.id,
            source_system=item.source_system,
            source_name=item.source.name,
            source_url=item.source_url,
            fish_name=item.fish_name,
            waterbody_name=item.waterbody_name,
            x=item.x,
            y=item.y,
            weight_g=item.weight_g,
            last_seen_at=item.last_seen_at,
            missing_fields=missing,
            quality="incomplete" if missing else "unverified",
        ))
    return result


@router.get("/api/v1/source-status", response_model=list[SourceStatusOut])
def source_status(db: Db) -> list[SourceStatusOut]:
    now = datetime.now(timezone.utc)
    result = []
    for source in db.scalars(select(DataSource).order_by(DataSource.name)):
        runs = list(db.scalars(
            select(CommunityImportRun)
            .where(CommunityImportRun.source_system == source.key)
            .order_by(CommunityImportRun.started_at.desc()).limit(20)
        ))
        latest = runs[0] if runs else None
        success = next((run for run in runs if run.status == "success"), None)
        if not source.enabled:
            state = "disabled"
        elif latest is None:
            state = "waiting"
        elif latest.status == "failed":
            state = "source_changed" if "CommunityParseError" in (latest.error_summary or "") else "temporarily_limited"
        elif aware(latest.started_at) < now - timedelta(seconds=settings.community_import_interval_seconds * 2):
            state = "stale"
        else:
            state = "healthy"
        result.append(SourceStatusOut(
            source_system=source.key,
            name=source.name,
            status=state,
            last_started_at=latest.started_at if latest else None,
            last_success_at=success.started_at if success else None,
            observations=db.scalar(
                select(func.count()).select_from(ExternalObservation)
                .where(ExternalObservation.source_system == source.key)
            ) or 0,
        ))
    return result


@router.get("/api/v1/records", response_model=PaginatedOfficialRecordOut)
def records(
    db: Db,
    fish: str | None = None,
    waterbody: str | None = None,
    category: str | None = None,
    q: str | None = None,
    limit: int = Query(50, ge=1, le=100),
    offset: int = Query(0, ge=0),
) -> PaginatedOfficialRecordOut:
    if q is not None and len(q) > 100:
        raise HTTPException(status_code=422, detail="record search query is too long")
    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)
    if category:
        query = query.where(CatchReport.raw_payload["category"].as_string() == category)
    if q and q.strip():
        needle = f"%{q.strip()}%"
        query = query.outerjoin(Bait, CatchReport.bait_id == Bait.id).where(or_(CatchReport.player_name.ilike(needle), Bait.name.ilike(needle)))
    total = db.scalar(
        query.with_only_columns(func.count(CatchReport.id), maintain_column_froms=True).order_by(None)
    ) or 0
    items = list(db.scalars(
        query.order_by(CatchReport.caught_at.desc(), CatchReport.weight_g.desc(), CatchReport.id.desc())
        .offset(offset).limit(limit)
    ))
    return PaginatedOfficialRecordOut(
        items=[OfficialRecordOut(
            id=item.id,
            fish=item.fish.name_ru,
            weight_g=item.weight_g,
            waterbody=item.waterbody.name_ru,
            bait=item.bait.name if item.bait else None,
            player_name=item.player_name,
            record_date=item.caught_at,
            category=(item.raw_payload or {}).get("category"),
            region=(item.raw_payload or {}).get("region"),
            source_url=item.source_url,
        ) for item in items],
        total=total,
        limit=limit,
        offset=offset,
    )


@router.get("/api/v1/imports", response_model=list[ImportRunPublicOut])
def imports(
    db: Db,
    limit: int = Query(20, ge=1, le=100),
    offset: int = Query(0, ge=0),
) -> list[OfficialRecordImport]:
    return list(db.scalars(
        select(OfficialRecordImport)
        .order_by(OfficialRecordImport.started_at.desc(), OfficialRecordImport.id.desc())
        .offset(offset).limit(limit)
    ))