package recipe

import (
	"encoding/json"
	"log/slog"
	"net/http"

	"github.com/food-ai/backend/internal/infra/middleware"
	"github.com/go-chi/chi/v5"
)

// Handler handles HTTP requests for recipes.
type Handler struct {
	repo *Repository
}

// NewHandler creates a new Handler.
func NewHandler(repo *Repository) *Handler {
	return &Handler{repo: repo}
}

// GetByID handles GET /recipes/{id}.
func (h *Handler) GetByID(w http.ResponseWriter, r *http.Request) {
	userID := middleware.UserIDFromCtx(r.Context())
	if userID == "" {
		writeErrorJSON(w, http.StatusUnauthorized, "unauthorized")
		return
	}

	id := chi.URLParam(r, "id")
	rec, err := h.repo.GetByID(r.Context(), id)
	if err != nil {
		slog.Error("get recipe", "id", id, "err", err)
		writeErrorJSON(w, http.StatusInternalServerError, "failed to get recipe")
		return
	}
	if rec == nil {
		writeErrorJSON(w, http.StatusNotFound, "recipe not found")
		return
	}
	writeJSON(w, http.StatusOK, rec)
}

type errorResponse struct {
	Error string `json:"error"`
}

func writeErrorJSON(w http.ResponseWriter, status int, msg string) {
	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(status)
	_ = json.NewEncoder(w).Encode(errorResponse{Error: msg})
}

func writeJSON(w http.ResponseWriter, status int, v any) {
	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(status)
	_ = json.NewEncoder(w).Encode(v)
}