from datetime import datetime, timezone

from fastapi import APIRouter, Depends, Request
from fastapi.responses import HTMLResponse, RedirectResponse
from sqlalchemy.orm import Session

from web.auth.session import get_current_user
from web.config import settings
from web.database import get_db
from web.models.connections import CachedGroup, CachedProduct, CachedStore, SyncConfig, SyncFilter
from web.templates_env import templates

router = APIRouter()


def _get_or_create_sync_config(db: Session, user_id: int) -> SyncConfig:
    cfg = db.query(SyncConfig).filter_by(user_id=user_id).first()
    if not cfg:
        cfg = SyncConfig(user_id=user_id, is_enabled=True)
        db.add(cfg)
        db.flush()
    return cfg


def _enabled_store_ids(db: Session, user_id: int) -> set[str] | None:
    """Return set of enabled store evotor_ids, or None if no filters set (all enabled)."""
    cfg = db.query(SyncConfig).filter_by(user_id=user_id).first()
    if not cfg:
        return None
    filters = db.query(SyncFilter).filter_by(
        sync_config_id=cfg.id, entity_type="store", filter_mode="include"
    ).all()
    if not filters:
        return None
    return {f.entity_id for f in filters}


def _enabled_group_ids(db: Session, user_id: int, store_evotor_id: str) -> set[str] | None:
    """Return set of enabled group evotor_ids for a store, or None if all enabled."""
    cfg = db.query(SyncConfig).filter_by(user_id=user_id).first()
    if not cfg:
        return None
    filters = db.query(SyncFilter).filter_by(
        sync_config_id=cfg.id, entity_type="group", filter_mode="include",
        parent_entity_id=store_evotor_id,
    ).all()
    if not filters:
        return None
    return {f.entity_id for f in filters}


def _render(request: Request, template: str, ctx: dict) -> HTMLResponse:
    ctx["request"] = request
    ctx.setdefault("jivosite_widget_id", settings.JIVOSITE_WIDGET_ID)
    return templates.TemplateResponse(ctx.pop("request"), template, ctx)


@router.get("/catalog/stores")
async def catalog_stores(request: Request, db: Session = Depends(get_db)):
    try:
        user = get_current_user(request, db)
    except Exception:
        return RedirectResponse("/login", 303)

    stores = (
        db.query(CachedStore)
        .filter(CachedStore.user_id == user.id)
        .order_by(CachedStore.name)
        .all()
    )
    enabled_ids = _enabled_store_ids(db, user.id)
    return _render(request, "catalog/stores.html", {
        "user": user,
        "stores": stores,
        "enabled_ids": enabled_ids,  # None = all enabled, set = explicit list
        "refresh_interval": settings.CATALOG_REFRESH_INTERVAL_SECONDS,
    })


@router.get("/catalog/stores/{store_evotor_id}/groups")
async def catalog_groups(store_evotor_id: str, request: Request, db: Session = Depends(get_db)):
    try:
        user = get_current_user(request, db)
    except Exception:
        return RedirectResponse("/login", 303)

    store = (
        db.query(CachedStore)
        .filter(CachedStore.user_id == user.id, CachedStore.evotor_id == store_evotor_id)
        .first()
    )
    if not store:
        return RedirectResponse("/catalog/stores", 303)

    groups = (
        db.query(CachedGroup)
        .filter(CachedGroup.user_id == user.id, CachedGroup.store_evotor_id == store_evotor_id)
        .order_by(CachedGroup.name)
        .all()
    )
    enabled_ids = _enabled_group_ids(db, user.id, store_evotor_id)
    return _render(request, "catalog/groups.html", {
        "user": user, "store": store, "groups": groups,
        "enabled_ids": enabled_ids,
    })


@router.get("/catalog/stores/{store_evotor_id}/products")
async def catalog_products(store_evotor_id: str, request: Request, db: Session = Depends(get_db)):
    try:
        user = get_current_user(request, db)
    except Exception:
        return RedirectResponse("/login", 303)

    store = (
        db.query(CachedStore)
        .filter(CachedStore.user_id == user.id, CachedStore.evotor_id == store_evotor_id)
        .first()
    )
    if not store:
        return RedirectResponse("/catalog/stores", 303)

    group_id = request.query_params.get("group")
    q = db.query(CachedProduct).filter(
        CachedProduct.user_id == user.id,
        CachedProduct.store_evotor_id == store_evotor_id,
    )
    if group_id:
        q = q.filter(CachedProduct.group_evotor_id == group_id)

    products = q.order_by(CachedProduct.name).all()
    groups = (
        db.query(CachedGroup)
        .filter(CachedGroup.user_id == user.id, CachedGroup.store_evotor_id == store_evotor_id)
        .order_by(CachedGroup.name)
        .all()
    )
    return _render(request, "catalog/products.html", {
        "user": user,
        "store": store,
        "products": products,
        "groups": groups,
        "group_id": group_id,
    })


@router.post("/catalog/stores/{store_evotor_id}/toggle")
async def catalog_store_toggle(store_evotor_id: str, request: Request, db: Session = Depends(get_db)):
    try:
        user = get_current_user(request, db)
    except Exception:
        return RedirectResponse("/login", 303)

    cfg = _get_or_create_sync_config(db, user.id)

    # If no filters exist yet, that means all stores are implicitly enabled.
    # Toggling one store OFF means we create include-filters for all OTHER stores.
    existing = db.query(SyncFilter).filter_by(
        sync_config_id=cfg.id, entity_type="store", filter_mode="include"
    ).all()
    existing_ids = {f.entity_id for f in existing}

    if store_evotor_id in existing_ids:
        # Currently enabled → disable: remove its filter
        db.query(SyncFilter).filter_by(
            sync_config_id=cfg.id, entity_type="store",
            entity_id=store_evotor_id, filter_mode="include",
        ).delete()
    else:
        if not existing_ids:
            # First toggle: seed include-filters for all OTHER stores
            all_stores = db.query(CachedStore).filter_by(user_id=user.id).all()
            now = datetime.now(timezone.utc).replace(tzinfo=None)
            for s in all_stores:
                if s.evotor_id == store_evotor_id:
                    continue
                db.add(SyncFilter(
                    sync_config_id=cfg.id,
                    entity_type="store",
                    entity_id=s.evotor_id,
                    entity_name=s.name,
                    filter_mode="include",
                    created_at=now,
                ))
        else:
            # Re-enable: add its filter back
            db.add(SyncFilter(
                sync_config_id=cfg.id,
                entity_type="store",
                entity_id=store_evotor_id,
                filter_mode="include",
                created_at=datetime.now(timezone.utc).replace(tzinfo=None),
            ))

    db.commit()
    return RedirectResponse("/catalog/stores", 303)


@router.post("/catalog/stores/{store_evotor_id}/groups/{group_evotor_id}/toggle")
async def catalog_group_toggle(
    store_evotor_id: str, group_evotor_id: str,
    request: Request, db: Session = Depends(get_db),
):
    try:
        user = get_current_user(request, db)
    except Exception:
        return RedirectResponse("/login", 303)

    cfg = _get_or_create_sync_config(db, user.id)

    existing = db.query(SyncFilter).filter_by(
        sync_config_id=cfg.id, entity_type="group", filter_mode="include",
        parent_entity_id=store_evotor_id,
    ).all()
    existing_ids = {f.entity_id for f in existing}

    if group_evotor_id in existing_ids:
        db.query(SyncFilter).filter_by(
            sync_config_id=cfg.id, entity_type="group",
            entity_id=group_evotor_id, filter_mode="include",
        ).delete()
    else:
        if not existing_ids:
            # First toggle: seed include-filters for all OTHER groups in this store
            all_groups = db.query(CachedGroup).filter_by(
                user_id=user.id, store_evotor_id=store_evotor_id,
            ).all()
            now = datetime.now(timezone.utc).replace(tzinfo=None)
            for g in all_groups:
                if g.evotor_id == group_evotor_id:
                    continue
                db.add(SyncFilter(
                    sync_config_id=cfg.id,
                    entity_type="group",
                    entity_id=g.evotor_id,
                    entity_name=g.name,
                    filter_mode="include",
                    parent_entity_id=store_evotor_id,
                    created_at=now,
                ))
        else:
            db.add(SyncFilter(
                sync_config_id=cfg.id,
                entity_type="group",
                entity_id=group_evotor_id,
                filter_mode="include",
                parent_entity_id=store_evotor_id,
                created_at=datetime.now(timezone.utc).replace(tzinfo=None),
            ))

    db.commit()
    return RedirectResponse(f"/catalog/stores/{store_evotor_id}/groups", 303)