"""Sprint 12 — external recipe search (Spoonacular) + import.

This is a thin HTTP layer on top of the pre-existing Spoonacular
free-tier API. The service-class `RecipeDiscoveryService` in
`app.services.recipe_discovery` is the bulk-orchestrator used by
the offline FeedbackAnalyzer; we re-implement the call shape here
because the webui wants:

1. A search that returns *summary* data (no info endpoint call) so
   10 results cost 1.1 points, not 11.1.
2. An import that fetches the full info for ONE recipe and writes
   a local Recipe row.

Quota: Spoonacular free tier = 150 points/day. complexSearch = 1 +
0.01 per result. /information = 1 point. We gate at 140 to leave
a safety margin and return 503 once exhausted.
"""
from __future__ import annotations

import logging
import threading
from typing import List, Optional

import requests
from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.orm import Session

from app.config import settings
from app.database import get_db
from app.models import FamilyProfile, Ingredient, Recipe
from app.schemas import (
    RecipeImportRequest,
    RecipeSearchHit,
)
from app.security import require_session

logger = logging.getLogger(__name__)

router = APIRouter()

# Quota counter: a per-process point budget. Survives across
# requests in the same uvicorn worker. Process restart resets to 0
# (so the operator can recover by bouncing the backend). Thread-safe
# with a single lock — the counter is touched on every request and
# we don't want a race between two parallel searches.
_quota_lock = threading.Lock()
_points_used: float = 0.0
_DAILY_LIMIT: float = 140.0  # 150 free, leave 10pt safety margin
_INFO_URL = "https://api.spoonacular.com/recipes/{id}/information"
_SEARCH_URL = "https://api.spoonacular.com/recipes/complexSearch"


def _points_available() -> float:
    with _quota_lock:
        return _DAILY_LIMIT - _points_used


def _charge_points(pts: float) -> None:
    global _points_used
    with _quota_lock:
        _points_used += pts


def _ensure_spoonacular_configured() -> str:
    """Return the API key, or 503 if unconfigured."""
    key = settings.SPOONACULAR_API_KEY
    if not key:
        logger.error("SPOONACULAR_API_KEY not configured")
        raise HTTPException(
            status_code=503,
            detail="SPOONACULAR_API_KEY not configured; set it in the backend env",
        )
    return key


def _normalize_spoonacular_summary(item: dict) -> Optional[RecipeSearchHit]:
    """Map a complexSearch result item into RecipeSearchHit."""
    ext_id = str(item.get("id") or "")
    title = item.get("title")
    if not ext_id or not title:
        return None
    cuisines = [str(c).lower() for c in (item.get("cuisines") or []) if c]
    diets = [str(d).lower() for d in (item.get("diets") or []) if d]
    return RecipeSearchHit(
        external_id=ext_id,
        external_source="spoonacular",
        name=title,
        image_url=item.get("image"),
        source_url=item.get("sourceUrl") or item.get("spoonacularSourceUrl"),
        prep_time_minutes=int(item["preparationMinutes"]) if item.get("preparationMinutes") else None,
        cook_time_minutes=int(item["cookingMinutes"]) if item.get("cookingMinutes") else None,
        servings=int(item["servings"]) if item.get("servings") else None,
        cuisine_tags=cuisines,
        dietary_tags=diets,
        protein_type=None,  # would need to call /information or _infer_protein
    )


@router.get("/search", response_model=List[RecipeSearchHit])
def search_recipes(
    q: str = Query(..., min_length=1, max_length=200),
    limit: int = Query(10, ge=1, le=25),
    _user: str = Depends(require_session),
) -> List[RecipeSearchHit]:
    """Search Spoonacular's complexSearch index and return a
    summary list (no per-recipe /information call). The frontend
    uses this for the "Search the web" panel."""
    if _points_available() < 1.05:  # 1 base + 0.01 * 5 average
        raise HTTPException(
            status_code=503,
            detail="spoonacular daily quota reached; try again tomorrow",
        )
    api_key = _ensure_spoonacular_configured()
    try:
        resp = requests.get(
            _SEARCH_URL,
            params={
                "apiKey": api_key,
                "query": q,
                "number": limit,
                "addRecipeInformation": "true",
                "fillIngredients": "true",
                "instructionsRequired": "true",
            },
            timeout=15,
        )
        resp.raise_for_status()
    except requests.RequestException as exc:
        logger.warning("Spoonacular search failed for %r: %s", q, exc)
        raise HTTPException(
            status_code=502,
            detail=f"spoonacular search failed: {exc}",
        ) from exc

    data = resp.json()
    results = data.get("results", [])
    # 1 base + 0.01 per result
    cost = 1.0 + len(results) * 0.01
    _charge_points(cost)
    logger.info("Spoonacular search %r → %d hits (%.2f pts, total %.1f/%.0f)",
                q, len(results), cost, _points_used, _DAILY_LIMIT)

    out: List[RecipeSearchHit] = []
    for item in results:
        hit = _normalize_spoonacular_summary(item)
        if hit:
            out.append(hit)
    return out


def _infer_protein_simple(title: str, ingredient_names: List[str]) -> Optional[str]:
    """Lightweight protein inference; mirrors recipe_discovery._infer_protein
    but doesn't import the service (to avoid pulling in the rest of the
    offline path)."""
    text = (title + " " + " ".join(ingredient_names)).lower()
    proteins = {
        "chicken": ["chicken"],
        "beef": ["beef", "steak", "ground beef"],
        "pork": ["pork", "bacon", "ham"],
        "fish": ["salmon", "tilapia", "cod", "fish fillet"],
        "shrimp": ["shrimp", "prawn"],
        "turkey": ["turkey"],
        "lamb": ["lamb"],
        "vegetarian": ["tofu", "tempeh", "vegetarian"],
    }
    for ptype, kws in proteins.items():
        for kw in kws:
            if kw in text:
                return ptype
    return None


def _upsert_ingredient(db: Session, name: str) -> Ingredient:
    """Idempotent insert by name_lower. Mirrors the public
    POST /api/ingredients logic without the HTTP roundtrip."""
    name_lower = name.lower()
    existing = db.query(Ingredient).filter(Ingredient.name_lower == name_lower).first()
    if existing:
        return existing
    row = Ingredient(name=name, name_lower=name_lower, aliases=[])
    db.add(row)
    try:
        db.commit()
        db.refresh(row)
    except Exception:
        db.rollback()
        existing = db.query(Ingredient).filter(Ingredient.name_lower == name_lower).first()
        if existing:
            return existing
        raise
    return row


@router.post("/import", response_model=dict, status_code=201)
def import_recipe(
    payload: RecipeImportRequest,
    db: Session = Depends(get_db),
    _user: str = Depends(require_session),
) -> dict:
    """Import a Spoonacular recipe into the local library. One
    /information call (1 point) + ingredient upserts + Recipe insert.
    Returns the new recipe id."""
    if payload.external_source != "spoonacular":
        raise HTTPException(status_code=400, detail=f"unknown external_source: {payload.external_source}")

    if _points_available() < 1.05:
        raise HTTPException(status_code=503, detail="spoonacular daily quota reached; try again tomorrow")
    api_key = _ensure_spoonacular_configured()

    # 1) Reject duplicates
    existing = (
        db.query(Recipe)
        .filter(Recipe.external_source == "spoonacular", Recipe.external_id == payload.external_id)
        .first()
    )
    if existing:
        raise HTTPException(status_code=409, detail=f"recipe already imported: {existing.id}")

    # 2) Fetch full info
    try:
        resp = requests.get(
            _INFO_URL.format(id=payload.external_id),
            params={"apiKey": api_key, "includeNutrition": "false"},
            timeout=15,
        )
        resp.raise_for_status()
    except requests.RequestException as exc:
        logger.warning("Spoonacular /information failed for %s: %s", payload.external_id, exc)
        raise HTTPException(status_code=502, detail=f"spoonacular info failed: {exc}") from exc

    full = resp.json()
    _charge_points(1.0)
    logger.info("Spoonacular import %s (1 pt, total %.1f/%.0f)",
                payload.external_id, _points_used, _DAILY_LIMIT)

    # 3) Resolve ingredients (upsert)
    ingredient_names: List[str] = []
    ingredients_json: List[dict] = []
    for ing in full.get("extendedIngredients", []):
        name = (ing.get("name") or ing.get("originalName") or "").strip()
        if not name:
            continue
        ingredient_names.append(name)
        local = _upsert_ingredient(db, name)
        qty = ing.get("amount")
        ingredients_json.append({
            "ingredient_id": str(local.id),
            "name": local.name,
            "qty": float(qty) if qty is not None else 1.0,
            "unit": ing.get("unit", "") or None,
            "notes": None,
        })

    # 4) Extract instructions
    instructions: List[str] = []
    analyzed = full.get("analyzedInstructions", [])
    if analyzed:
        for step in analyzed[0].get("steps", []):
            txt = step.get("step", "")
            if txt:
                instructions.append(txt)
    if not instructions:
        raw = full.get("instructions", "")
        if raw:
            instructions = [raw]

    # 5) Build the Recipe
    title = full.get("title") or "Untitled"
    cuisines = [str(c).lower() for c in (full.get("cuisines") or []) if c]
    diets = [str(d).lower() for d in (full.get("diets") or []) if d]

    # 6) Resolve family_profile_id (require_session auto-fills first profile)
    profile = db.query(FamilyProfile).first()
    if not profile:
        raise HTTPException(status_code=404, detail="family profile not found")

    row = Recipe(
        family_profile_id=profile.id,
        name=title,
        description=full.get("summary"),
        image_url=full.get("image"),
        image_source="spoonacular",
        prep_time_minutes=int(full["preparationMinutes"]) if full.get("preparationMinutes") else None,
        cook_time_minutes=int(full["cookingMinutes"]) if full.get("cookingMinutes") else None,
        servings=int(full.get("servings", 4)),
        cuisine_tags=cuisines,
        dietary_tags=diets,
        protein_type=_infer_protein_simple(title, ingredient_names),
        ingredients=ingredients_json,
        side_dishes=[],
        instructions=instructions or ["See source for instructions."],
        source_url=full.get("sourceUrl") or full.get("spoonacularSourceUrl"),
        scraped_at=None,
        is_manually_added=True,
        external_source="spoonacular",
        external_id=payload.external_id,
        discovery_reason="user imported via webui",
    )
    db.add(row)
    db.commit()
    db.refresh(row)

    return {
        "id": str(row.id),
        "name": row.name,
        "external_id": row.external_id,
        "ingredients_imported": len(ingredients_json),
    }