"""API de autoayuno: catálogo compartido de alimentos (alimentado de Open Food
Facts bajo demanda) y recetas publicables. Sin cuentas: publicar es anónimo con
un deviceToken."""
import uuid

from fastapi import Depends, FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from pydantic import BaseModel
from sqlalchemy import func, text
from sqlalchemy.orm import Session


def like_pattern(q: str) -> str:
    """Escapa comodines de LIKE (%, _, \\) para tratar la query como texto."""
    q = q.replace("\\", "\\\\").replace("%", "\\%").replace("_", "\\_")
    return f"%{q.lower()}%"


def clamp_limit(limit: int) -> int:
    return max(1, min(limit, 50))

import off
from db import Base, engine, get_db
from models import Food, Recipe, TelemetryDaily


# Columnas añadidas a `recipes` después de la v1 (id/name/servings/items). En
# Postgres la tabla ya existe y `create_all` NO la altera, así que las añadimos a
# mano (idempotente). En SQLite fresco no hace falta: `create_all` ya las trae.
_RECIPE_NEW_COLUMNS = {
    "category": "VARCHAR DEFAULT 'otros'",
    "prep_minutes": "INTEGER",
    "steps": "JSON",
    "notes": "VARCHAR",
    "author_id": "VARCHAR",
    "author_name": "VARCHAR",
    "parent_id": "VARCHAR",
    "parent_author_name": "VARCHAR",
    "root_id": "VARCHAR",
    "root_author_name": "VARCHAR",
    "visibility": "VARCHAR DEFAULT 'public'",
    "updated_at": "TIMESTAMP",
}


def _migrate_recipes():
    """Añade en Postgres las columnas nuevas de `recipes` si faltan (best-effort)."""
    if not engine.url.get_backend_name().startswith("postgres"):
        return
    try:
        with engine.begin() as conn:
            for name, ddl in _RECIPE_NEW_COLUMNS.items():
                try:
                    conn.execute(text(
                        f"ALTER TABLE recipes ADD COLUMN IF NOT EXISTS {name} {ddl}"))
                except Exception:
                    pass
    except Exception:
        pass


def _migrate_telemetry():
    """Añade en Postgres la columna `seconds` de `telemetry_daily` si falta
    (la tabla ya existe desde v2.27 sin esa columna; create_all no la altera)."""
    if not engine.url.get_backend_name().startswith("postgres"):
        return
    try:
        with engine.begin() as conn:
            conn.execute(text(
                "ALTER TABLE telemetry_daily ADD COLUMN IF NOT EXISTS "
                "seconds INTEGER DEFAULT 0"))
    except Exception:
        pass


def init_db(retries: int = 10):
    """Crea las tablas, reintentando por si la BD tarda en levantar. No tumba
    el arranque si falla: /health seguirá respondiendo."""
    import time
    for _ in range(retries):
        try:
            Base.metadata.create_all(bind=engine)
            _migrate_recipes()
            _migrate_telemetry()
            return True
        except Exception:
            time.sleep(2)
    return False


# En import: un intento best-effort (crea tablas ya para tests/SQLite).
init_db(retries=1)

app = FastAPI(title="autoayuno-api")


@app.on_event("startup")
def _startup():
    init_db()
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_methods=["*"],
    allow_headers=["*"],
)


@app.get("/health")
def health():
    return {"status": "ok"}


# ---------------------------------------------------------------------------
# Alimentos
# ---------------------------------------------------------------------------

class PortionIn(BaseModel):
    name: str
    grams: float


class FoodIn(BaseModel):
    id: str | None = None
    name: str
    kcalPer100g: float
    zone: str = "otros"
    portions: list[PortionIn] = []  # validado: cada ración necesita name+grams
    barcode: str | None = None
    deviceToken: str | None = None


@app.get("/foods")
def search_foods(q: str = "", limit: int = 20, db: Session = Depends(get_db)):
    q = (q or "").strip()
    limit = clamp_limit(limit)
    if len(q) < 2:
        return []
    local = (
        db.query(Food)
        .filter(func.lower(Food.name).like(like_pattern(q), escape="\\"))
        .limit(limit)
        .all()
    )
    results = [f.to_app() for f in local]

    # Si hay pocos, enriquecemos con Open Food Facts y guardamos.
    if len(local) < 5:
        items = off.search(q)
        # Dedupe en una sola query (evita N+1 contra Postgres).
        off_ids = [i["off_id"] for i in items if i.get("off_id")]
        existing = set()
        if off_ids:
            existing = {
                r[0]
                for r in db.query(Food.off_id).filter(Food.off_id.in_(off_ids)).all()
            }
        seen_names = {f.name.lower() for f in local}
        for item in items:
            if item.get("off_id") and item["off_id"] in existing:
                continue
            if item["name"].lower() in seen_names:
                continue
            food = Food(
                id=str(uuid.uuid4()),
                name=item["name"],
                kcal_100g=item["kcal_100g"],
                zone="otros",
                portions=[],
                barcode=item.get("barcode"),
                source="off",
                off_id=item.get("off_id"),
            )
            db.add(food)
            seen_names.add(item["name"].lower())
            if item.get("off_id"):
                existing.add(item["off_id"])
            results.append(food.to_app())
        db.commit()
    return results[:limit]


@app.post("/foods")
def add_food(body: FoodIn, db: Session = Depends(get_db)):
    portions = [p.model_dump() for p in body.portions]
    # Upsert por id del cliente: republicar actualiza en vez de duplicar.
    food = db.get(Food, body.id) if body.id else None
    if food is None:
        food = Food(id=body.id or str(uuid.uuid4()), source="user")
        db.add(food)
    food.name = body.name.strip()[:120]
    food.kcal_100g = body.kcalPer100g
    food.zone = body.zone
    food.portions = portions
    food.barcode = body.barcode
    food.author_token = body.deviceToken
    db.commit()
    return food.to_app()


# ---------------------------------------------------------------------------
# Recetas
# ---------------------------------------------------------------------------

class FoodSnapshotIn(BaseModel):
    name: str
    kcalPer100g: float
    zone: str = "otros"
    portions: list[PortionIn] = []


class RecipeItemIn(BaseModel):
    food: FoodSnapshotIn
    grams: float
    portionLabel: str | None = None


class RecipeIn(BaseModel):
    id: str | None = None
    name: str
    servings: int = 1
    items: list[RecipeItemIn] = []  # validado: cada item necesita food+grams
    category: str = "otros"
    prepMinutes: int | None = None
    steps: list[str] = []
    notes: str | None = None
    authorId: str | None = None
    authorName: str | None = None
    parentId: str | None = None
    parentAuthorName: str | None = None
    rootId: str | None = None
    rootAuthorName: str | None = None
    visibility: str = "public"
    deviceToken: str | None = None


@app.get("/recipes")
def search_recipes(q: str = "", limit: int = 20, db: Session = Depends(get_db)):
    # Buscar solo devuelve recetas PÚBLICAS (las privadas/no listadas no salen).
    query = db.query(Recipe).filter(Recipe.visibility == "public")
    q = (q or "").strip()
    if q:
        query = query.filter(func.lower(Recipe.name).like(like_pattern(q), escape="\\"))
    return [r.to_app() for r in query.limit(clamp_limit(limit)).all()]


@app.get("/recipes/{recipe_id}")
def get_recipe(recipe_id: str, db: Session = Depends(get_db)):
    r = db.query(Recipe).filter(Recipe.id == recipe_id).first()
    if r is None:
        raise HTTPException(status_code=404, detail="receta no encontrada")
    return r.to_app()


@app.get("/cookbook/{author_id}")
def cookbook(author_id: str, db: Session = Depends(get_db)):
    """Todas las recetas de un autor (para respaldo/restaurar; usado en B3)."""
    rows = db.query(Recipe).filter(Recipe.author_id == author_id).all()
    return [r.to_app() for r in rows]


@app.delete("/cookbook/{author_id}")
def delete_cookbook(author_id: str, db: Session = Depends(get_db)):
    """Opt-out del respaldo: borra las copias PRIVADAS de un autor. Lo que
    publicó a propósito (pública / no listada) se mantiene."""
    n = (
        db.query(Recipe)
        .filter(Recipe.author_id == author_id, Recipe.visibility == "private")
        .delete()
    )
    db.commit()
    return {"deleted": n}


# ---------------------------------------------------------------------------
# Telemetría de uso ANÓNIMA (opt-in en la app; apagada por defecto)
# ---------------------------------------------------------------------------

class TelemetryIn(BaseModel):
    day: str
    app_version: str | None = None
    active_modules: list[str] = []
    opens_by_module: dict[str, int] = {}
    seconds_by_module: dict[str, int] = {}


@app.post("/telemetry")
def add_telemetry(body: TelemetryIn, db: Session = Depends(get_db)):
    """Recibe un lote diario y agregado de uso. NO lleva identificador: solo
    incrementa contadores por día y módulo/vista. No guarda IP, nombre ni
    contenido."""
    day = (body.day or "").strip()[:10]
    if len(day) != 10:
        raise HTTPException(status_code=400, detail="day inválido (YYYY-MM-DD)")

    # Agregamos los incrementos de ESTE envío por clave antes de tocar la BD:
    # una clave puede aparecer en varios mapas, y crear dos filas pendientes con
    # la misma PK reventaría el INSERT.
    agg: dict[str, dict[str, int]] = {}

    def add(module: str, active: int = 0, opens: int = 0, seconds: int = 0):
        module = str(module).strip()[:40]
        if not module:
            return
        e = agg.setdefault(module, {"active": 0, "opens": 0, "seconds": 0})
        e["active"] += active
        e["opens"] += opens
        e["seconds"] += seconds

    # Un envío = una instalación activa ese día que cede estadística.
    add("__submissions__", active=1)
    for m in (body.active_modules or [])[:40]:
        add(m, active=1)
    for m, c in (body.opens_by_module or {}).items():
        try:
            c = int(c)
        except (TypeError, ValueError):
            continue
        if c > 0:
            add(m, opens=min(c, 100000))
    for m, s in (body.seconds_by_module or {}).items():
        try:
            s = int(s)
        except (TypeError, ValueError):
            continue
        if s > 0:
            # Tope por clave y envío (~1 día): evita valores absurdos.
            add(m, seconds=min(s, 86400))

    for module, delta in agg.items():
        row = db.get(TelemetryDaily, (day, module))
        if row is None:
            row = TelemetryDaily(day=day, module=module, active=0, opens=0, seconds=0)
            db.add(row)
        row.active = (row.active or 0) + delta["active"]
        row.opens = (row.opens or 0) + delta["opens"]
        row.seconds = (row.seconds or 0) + delta["seconds"]
    db.commit()
    return {"ok": True}


@app.get("/telemetry/summary")
def telemetry_summary(days: int = 30, db: Session = Depends(get_db)):
    """Resumen agregado de los últimos [days] días: envíos y, por módulo, en
    cuántos días-instalación estuvo activo y cuántas veces se abrió."""
    from datetime import date, timedelta
    days = max(1, min(days, 3650))
    cutoff = (date.today() - timedelta(days=days)).isoformat()
    rows = (
        db.query(
            TelemetryDaily.module,
            func.sum(TelemetryDaily.active),
            func.sum(TelemetryDaily.opens),
            func.sum(TelemetryDaily.seconds),
        )
        .filter(TelemetryDaily.day >= cutoff)
        .group_by(TelemetryDaily.module)
        .all()
    )
    submissions = 0
    modules = []
    for module, active, opens, seconds in rows:
        if module == "__submissions__":
            submissions = int(active or 0)
            continue
        modules.append({
            "module": module,
            "activeInstallDays": int(active or 0),
            "opens": int(opens or 0),
            "seconds": int(seconds or 0),
        })
    modules.sort(key=lambda x: x["opens"], reverse=True)
    return {"sinceDays": days, "submissions": submissions, "modules": modules}


@app.post("/recipes")
def add_recipe(body: RecipeIn, db: Session = Depends(get_db)):
    items = [i.model_dump() for i in body.items]
    r = db.get(Recipe, body.id) if body.id else None
    if r is None:
        r = Recipe(id=body.id or str(uuid.uuid4()))
        db.add(r)
    r.name = body.name.strip()[:140]
    r.servings = body.servings
    r.items = items
    r.category = (body.category or "otros")[:20]
    r.prep_minutes = body.prepMinutes
    r.steps = [str(s)[:500] for s in (body.steps or [])][:60]
    r.notes = (body.notes or None)
    r.author_id = body.authorId
    r.author_name = (body.authorName or None)
    r.parent_id = body.parentId
    r.parent_author_name = body.parentAuthorName
    r.root_id = body.rootId
    r.root_author_name = body.rootAuthorName
    r.visibility = body.visibility if body.visibility in (
        "private", "unlisted", "public") else "public"
    r.author_token = body.deviceToken
    db.commit()
    return r.to_app()