package handler

import (
	"encoding/json"
	"errors"
	"net/http"
	"strings"

	"5803025048/W04/internal/middleware"
	"5803025048/W04/internal/models"
	"5803025048/W04/internal/store"
	"github.com/google/uuid"
)

type SnippetHandler struct {
	snippetStore SnippetStore
}

func NewSnippetHandler(snippetStore SnippetStore) *SnippetHandler {
	return &SnippetHandler{snippetStore: snippetStore}
}

type snippetRequest struct {
	Title   string `json:"title"`
	Content string `json:"content"`
}

func snippetID(r *http.Request) string {
	id := r.PathValue("id")
	if id == "" {
		path := strings.TrimPrefix(r.URL.Path, "/snippets/")
		id = strings.TrimSuffix(path, "/")
	}
	return id
}

func (h *SnippetHandler) Create(w http.ResponseWriter, r *http.Request) {
	userID := middleware.GetUserID(r.Context())
	if userID == "" {
		writeError(w, http.StatusUnauthorized, "Unauthorized")
		return
	}

	var req snippetRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		writeError(w, http.StatusBadRequest, "Bad Request")
		return
	}

	req.Title = strings.TrimSpace(req.Title)
	req.Content = strings.TrimSpace(req.Content)
	if req.Title == "" || req.Content == "" {
		writeError(w, http.StatusBadRequest, "Title and content are required")
		return
	}

	snippet := &models.Snippet{
		ID:      uuid.New().String(),
		Title:   req.Title,
		Content: req.Content,
		UserID:  userID,
	}

	if err := h.snippetStore.Create(r.Context(), snippet); err != nil {
		writeError(w, http.StatusInternalServerError, "Internal Server Error")
		return
	}

	writeJSON(w, http.StatusCreated, snippet)
}

func (h *SnippetHandler) List(w http.ResponseWriter, r *http.Request) {
	userID := middleware.GetUserID(r.Context())
	if userID == "" {
		writeError(w, http.StatusUnauthorized, "Unauthorized")
		return
	}

	snippets, err := h.snippetStore.GetByUserID(r.Context(), userID)
	if err != nil {
		writeError(w, http.StatusInternalServerError, "Internal Server Error")
		return
	}
	if snippets == nil {
		// Pastikan selalu "[]", bukan "null".
		snippets = []*models.Snippet{}
	}

	writeJSON(w, http.StatusOK, snippets)
}

func (h *SnippetHandler) Get(w http.ResponseWriter, r *http.Request) {
	id := snippetID(r)
	if id == "" {
		writeError(w, http.StatusBadRequest, "Bad Request")
		return
	}

	snippet, err := h.snippetStore.GetByID(r.Context(), id)
	if err != nil {
		if errors.Is(err, store.ErrNotFound) {
			writeError(w, http.StatusNotFound, "Snippet not found")
			return
		}
		writeError(w, http.StatusInternalServerError, "Internal Server Error")
		return
	}

	writeJSON(w, http.StatusOK, snippet)
}

func (h *SnippetHandler) Delete(w http.ResponseWriter, r *http.Request) {
	userID := middleware.GetUserID(r.Context())
	if userID == "" {
		writeError(w, http.StatusUnauthorized, "Unauthorized")
		return
	}

	id := snippetID(r)
	if id == "" {
		writeError(w, http.StatusBadRequest, "Bad Request")
		return
	}

	snippet, err := h.snippetStore.GetByID(r.Context(), id)
	if err != nil {
		if errors.Is(err, store.ErrNotFound) {
			writeError(w, http.StatusNotFound, "Snippet not found")
			return
		}
		writeError(w, http.StatusInternalServerError, "Internal Server Error")
		return
	}

	if snippet.UserID != userID {
		writeError(w, http.StatusForbidden, "Forbidden")
		return
	}

	if err := h.snippetStore.Delete(r.Context(), id); err != nil {
		if errors.Is(err, store.ErrNotFound) {
			writeError(w, http.StatusNotFound, "Snippet not found")
			return
		}
		writeError(w, http.StatusInternalServerError, "Internal Server Error")
		return
	}

	w.WriteHeader(http.StatusNoContent)
}