from __future__ import annotations

import datetime
from typing import List, Optional

import aiosqlite
from fastapi import APIRouter, Depends, Query, Request, Response

import meals
import ingredients
import persons
import shopping
from api.deps import cookie_person, error_response, get_db
from common import ProblemDetails, ApiModel, Field

router = APIRouter(prefix="/meals", tags=["meals"])


class MealOut(ApiModel):
    id: int = -1
    suggested_date: datetime.datetime
    consumed_date: Optional[datetime.datetime] = None
    chefs: List[persons.Person] = Field(min_length=0, json_schema_extra={"minItems": 0})
    cleanup: List[persons.Person] = Field(min_length=0, json_schema_extra={"minItems": 0})
    consumers: List[persons.Person] = Field(min_length=0, json_schema_extra={"minItems": 0})
    recipes: List[meals.MealRecipe] = Field(min_length=0, json_schema_extra={"minItems": 0})
    extra_ingredients: List[ingredients.Ingredient] = Field(
        min_length=0, json_schema_extra={"minItems": 0}
    )
    purchase_date: Optional[datetime.datetime] = None


@router.get(
    "/upcoming", operation_id="getUpcomingMeals", summary="List upcoming meals in a date range"
)
async def get_upcoming_meals(
    date_from: datetime.datetime = Query(..., alias="from"),
    to: datetime.datetime = Query(...),
    conn: aiosqlite.Connection = Depends(get_db),
) -> List[meals.Meal]:
    # Load base meals
    result: List[meals.Meal] = []
    async for meal in meals.find_upcoming_meals_by_date_range(conn, date_from, to):
        result.append(meal)

    if not result:
        return result

    # Batch load participants for all meals
    await meals.bulk_load_participants(conn, result)

    # Load recipes and extra ingredients per meal (recipes include a small join)
    for meal in result:
        await meals.load_recipes(conn, meal)
        await meals.load_extra_ingredients(conn, meal)

    return result


@router.get(
    "/{meal_id}",
    response_model=MealOut,
    operation_id="getMeal",
    summary="Get a meal by id",
    responses={
        404: {
            "model": ProblemDetails,
            "description": "Meal not found",
            "content": {"application/problem+json": {}},
        }
    },
)
async def get_meal(
    meal_id: int, request: Request, conn: aiosqlite.Connection = Depends(get_db)
) -> meals.Meal | Response:
    meal = await meals.find_meal_by_id(conn, meal_id)
    if not meal:
        return error_response(request, 404, "Meal not found")

    return meal


@router.post(
    "",
    response_model=MealOut,
    operation_id="createMeal",
    summary="Create a new meal",
    responses={
        400: {
            "model": ProblemDetails,
            "description": "Validation error",
            "content": {"application/problem+json": {}},
        }
    },
)
async def create_meal(
    meal: meals.Meal,
    request: Request,
    response: Response,
    conn: aiosqlite.Connection = Depends(get_db),
) -> meals.Meal | Response:
    validation_response = validate_meal(meal, request)
    if validation_response:
        return validation_response

    await meals.insert_meal(conn, meal)
    response.headers["Location"] = f"/api/v1/meals/{meal.id}"
    return meal


@router.put(
    "/{meal_id}",
    response_model=MealOut,
    operation_id="updateMeal",
    summary="Update an existing meal",
    responses={
        400: {
            "model": ProblemDetails,
            "description": "Validation error",
            "content": {"application/problem+json": {}},
        },
        404: {
            "model": ProblemDetails,
            "description": "Meal not found",
            "content": {"application/problem+json": {}},
        },
    },
)
async def update_meal(
    meal_id: int, meal: meals.Meal, request: Request, conn: aiosqlite.Connection = Depends(get_db)
) -> meals.Meal | Response:
    if meal.id != meal_id:
        return error_response(request, 400, "Meal ID in URL does not match meal ID in body")

    existing = await meals.find_meal_by_id(conn, meal_id)
    if not existing:
        return error_response(request, 404, "Meal not found")

    validation_response = validate_meal(meal, request)
    if validation_response:
        return validation_response

    await meals.update_meal(conn, meal)

    # Re-fetch and return the updated meal. Pass request and conn explicitly to avoid Depends resolution.
    return await get_meal(meal_id, request, conn)


@router.post(
    "/{meal_id}/consumed",
    response_model=MealOut,
    operation_id="markMealConsumed",
    summary="Mark a meal as consumed",
    responses={
        400: {
            "model": ProblemDetails,
            "description": "Validation error",
            "content": {"application/problem+json": {}},
        },
        404: {
            "model": ProblemDetails,
            "description": "Meal not found",
            "content": {"application/problem+json": {}},
        },
    },
)
async def mark_consumed(
    meal_id: int,
    request: Request,
    consumed_date: Optional[datetime.datetime] = None,
    conn: aiosqlite.Connection = Depends(get_db),
    person: persons.Person = Depends(cookie_person),
) -> meals.Meal | Response:
    if consumed_date and not consumed_date.tzinfo:
        return error_response(request, 400, "Consumed date must include timezone")

    meal = await meals.find_meal_by_id(conn, meal_id)
    if not meal:
        return error_response(request, 404, "Meal not found")

    await meals.mark_consumed(conn, meal, consumed_date or datetime.datetime.now().astimezone())
    await shopping.remove_request(conn, person, meal=meal)

    return meal


@router.delete(
    "/{meal_id}",
    response_model=MealOut,
    operation_id="deleteMeal",
    summary="Delete a meal",
    responses={
        404: {
            "model": ProblemDetails,
            "description": "Meal not found",
            "content": {"application/problem+json": {}},
        }
    },
)
async def delete_meal(
    meal_id: int,
    request: Request,
    conn: aiosqlite.Connection = Depends(get_db),
    person: persons.Person = Depends(cookie_person),
) -> meals.Meal | Response:
    meal = await meals.find_meal_by_id(conn, meal_id)
    if not meal:
        return error_response(request, 404, "Meal not found")

    await shopping.remove_request(conn, person, meal=meal)
    await meals.delete_meal(conn, meal.id)
    return meal


def validate_meal(meal: meals.Meal, request: Optional[Request] = None) -> Optional[Response]:
    """HTTP-friendly wrapper that maps service validation to ProblemDetails."""
    msg = meals.validate_meal(meal)
    if msg:
        return error_response(request, 400, msg)
    return None