"""Portable JSON for user food mappings, manual foods, and FDDB lists."""
from __future__ import annotations

from datetime import datetime, timezone
from decimal import Decimal
from typing import Any
from uuid import UUID

from data_layer.food_mapping import (
    apply_mapping_to_items,
    apply_quantities_to_items,
    normalize_food_name,
    upsert_food_mapping,
)
from data_layer.food_recipes import list_recipes, upsert_recipes
from data_layer.nutrition_items import catalog_macros_for_item, dates_for_normalized_name, rebuild_daily_nutrients

BUNDLE_FORMAT = "mitai-food-knowledge"
BUNDLE_VERSION = 1


def _jsonable(value: Any) -> Any:
    if value is None:
        return None
    if isinstance(value, Decimal):
        return float(value)
    if isinstance(value, UUID):
        return str(value)
    if hasattr(value, "isoformat"):
        return value.isoformat()
    return value


def parse_food_knowledge_bundle(data: Any) -> dict[str, Any]:
    if not isinstance(data, dict):
        raise ValueError("Die Datei ist kein JSON-Objekt")
    if data.get("format") != BUNDLE_FORMAT:
        raise ValueError("Keine Mitai-Zuordnungsdatei — bitte die exportierte JSON verwenden")
    try:
        version = int(data.get("version") or 0)
    except (TypeError, ValueError) as exc:
        raise ValueError("Unbekannte Dateiversion") from exc
    if version != BUNDLE_VERSION:
        raise ValueError(f"Nicht unterstützte Dateiversion {version}")
    return data


def portable_mapping(row: dict[str, Any]) -> dict[str, Any]:
    return {
        "source_system": row.get("source_system") or "fddb",
        "source_name_raw": row.get("source_name_raw"),
        "source_name_normalized": row.get("source_name_normalized"),
        "bls_code": row.get("bls_code"),
        "food_name_de": row.get("food_name_de") or row.get("name_de"),
        "catalog_kind": row.get("catalog_kind"),
        "external_key": row.get("external_key"),
        "grams_per_unit": row.get("grams_per_unit"),
        "source_unit": row.get("source_unit"),
    }


def resolve_catalog_food(cur, profile_id: str, ref: dict[str, Any]) -> str | None:
    bls = (ref.get("bls_code") or "").strip()
    if bls:
        cur.execute(
            "SELECT id FROM food_catalog WHERE bls_code = %s AND is_active = true",
            (bls,),
        )
        row = cur.fetchone()
        return str(row["id"]) if row else None
    kind = ref.get("catalog_kind") or "manual_user"
    name = (ref.get("food_name_de") or ref.get("name_de") or "").strip()
    key = (ref.get("external_key") or "").strip()
    if kind == "manual_user":
        if key:
            cur.execute(
                """
                SELECT id FROM food_catalog
                WHERE owner_profile_id = %s AND external_key = %s AND is_active = true
                LIMIT 1
                """,
                (profile_id, key),
            )
            row = cur.fetchone()
            if row:
                return str(row["id"])
        if name:
            cur.execute(
                """
                SELECT id FROM food_catalog
                WHERE owner_profile_id = %s AND catalog_kind = 'manual_user'
                  AND lower(name_de) = lower(%s) AND is_active = true
                LIMIT 1
                """,
                (profile_id, name),
            )
            row = cur.fetchone()
            if row:
                return str(row["id"])
        return None
    if kind == "manual_admin" and name:
        cur.execute(
            """
            SELECT id FROM food_catalog
            WHERE catalog_kind = 'manual_admin' AND lower(name_de) = lower(%s)
              AND is_active = true
            LIMIT 1
            """,
            (name,),
        )
        row = cur.fetchone()
        return str(row["id"]) if row else None
    return None


def export_food_knowledge(cur, profile_id: str) -> dict[str, Any]:
    cur.execute(
        """
        SELECT id, name_de, name_en, catalog_kind, external_key
        FROM food_catalog
        WHERE owner_profile_id = %s AND catalog_kind = 'manual_user' AND is_active = true
        ORDER BY lower(name_de)
        """,
        (profile_id,),
    )
    manuals = []
    for food in cur.fetchall():
        macros = catalog_macros_for_item(cur, food["id"], 100.0)
        manuals.append({
            "name_de": food["name_de"],
            "name_en": food.get("name_en"),
            "catalog_kind": food["catalog_kind"],
            "external_key": food.get("external_key"),
            "macros_per_100g": macros,
        })
    cur.execute(
        """
        SELECT m.source_system, m.source_name_raw, m.source_name_normalized,
               m.grams_per_unit, m.source_unit,
               f.bls_code, f.name_de AS food_name_de, f.catalog_kind, f.external_key
        FROM food_name_mappings m
        JOIN food_catalog f ON f.id = m.food_id
        WHERE m.profile_id = %s
        ORDER BY m.source_name_normalized
        """,
        (profile_id,),
    )
    mappings = [portable_mapping(dict(r)) for r in cur.fetchall()]
    recipes = []
    for rec in list_recipes(cur, profile_id):
        recipes.append({
            "name_raw": rec.get("name_raw"),
            "name_normalized": rec.get("name_normalized"),
            "portions": _jsonable(rec.get("portions")),
            "description": rec.get("description"),
            "source": rec.get("source") or "fddb_list",
            "ingredients": [
                {
                    "source_name_raw": ing.get("source_name_raw"),
                    "source_name_normalized": ing.get("source_name_normalized"),
                    "quantity_raw": ing.get("quantity_raw"),
                    "quantity_g": _jsonable(ing.get("quantity_g")),
                    "sort_order": ing.get("sort_order") or 0,
                }
                for ing in rec.get("ingredients") or []
            ],
        })
    return {
        "format": BUNDLE_FORMAT,
        "version": BUNDLE_VERSION,
        "exported_at": datetime.now(timezone.utc).isoformat(),
        "manual_foods": manuals,
        "mappings": mappings,
        "recipes": recipes,
    }


def _upsert_manual_food(cur, profile_id: str, food: dict[str, Any]) -> str | None:
    name = (food.get("name_de") or "").strip()
    if not name:
        return None
    existing = resolve_catalog_food(cur, profile_id, {**food, "food_name_de": name, "catalog_kind": "manual_user"})
    if existing:
        from routers.admin_bls import _write_manual_macros
        _write_manual_macros(cur, existing, food.get("macros_per_100g"))
        return existing
    key = (food.get("external_key") or "").strip() or f"man-user-{normalize_food_name(name)[:40]}"
    cur.execute(
        """
        INSERT INTO food_catalog
            (name_de, name_en, catalog_kind, owner_profile_id, source, external_key)
        VALUES (%s, %s, 'manual_user', %s, 'import', %s)
        RETURNING id
        """,
        (name, food.get("name_en"), profile_id, key),
    )
    food_id = str(cur.fetchone()["id"])
    from routers.admin_bls import _write_manual_macros
    _write_manual_macros(cur, food_id, food.get("macros_per_100g"))
    return food_id


def import_food_knowledge(cur, profile_id: str, data: dict[str, Any]) -> dict[str, Any]:
    bundle = parse_food_knowledge_bundle(data)
    foods_upserted = 0
    for food in bundle.get("manual_foods") or []:
        if _upsert_manual_food(cur, profile_id, food):
            foods_upserted += 1
    mappings_ok = mappings_skipped = items_updated = 0
    skipped: list[str] = []
    dates: set[str] = set()
    for raw in bundle.get("mappings") or []:
        name = (raw.get("source_name_raw") or "").strip()
        if not name:
            mappings_skipped += 1
            continue
        food_id = resolve_catalog_food(cur, profile_id, raw)
        if not food_id:
            mappings_skipped += 1
            label = raw.get("bls_code") or raw.get("food_name_de") or name
            skipped.append(str(label))
            continue
        mid = upsert_food_mapping(
            cur,
            source_name_raw=name,
            food_id=food_id,
            profile_id=profile_id,
            source="import",
            source_system=raw.get("source_system") or "fddb",
            grams_per_unit=raw.get("grams_per_unit"),
            source_unit=raw.get("source_unit"),
        )
        norm = normalize_food_name(name)
        items_updated += apply_mapping_to_items(cur, profile_id, norm, food_id, mid)
        apply_quantities_to_items(cur, profile_id, norm, raw.get("grams_per_unit"))
        dates.update(dates_for_normalized_name(cur, profile_id, norm))
        mappings_ok += 1
    recipe_stats = {"inserted": 0, "updated": 0, "ingredients": 0, "items_linked": 0}
    recipes = bundle.get("recipes") or []
    if recipes:
        recipe_stats = upsert_recipes(cur, profile_id, recipes)
        dates.update(recipe_stats.pop("dates_linked", []) or [])
    for day in dates:
        rebuild_daily_nutrients(cur, profile_id, day)
    return {
        "ok": True,
        "manual_foods": foods_upserted,
        "mappings": mappings_ok,
        "mappings_skipped": mappings_skipped,
        "items_updated": items_updated,
        "skipped_foods": skipped[:20],
        **recipe_stats,
    }