<?php

namespace App\Http\Controllers;
use App\Models\MusicPlaylist;
use App\Models\MusicCategory;
use Illuminate\Support\Str;
use Illuminate\Http\Request;

class MusicCategoryController extends Controller
{
    public function index()
    {
        $categories = MusicCategory::with(['image', 'playlists' => function($q) {
            $q->where('is_active', true)->orderBy('order');
        }])->where('is_active', true)->orderBy('order')->get();
        
        return response()->json($categories);
    }
    
    public function store(Request $request)
    {
        try {
            $data = $request->validate([
                'name' => 'required|string|max:255',
                'description' => 'nullable|string',
                'image_id' => 'nullable|exists:images,id',
                'order' => 'nullable|integer',
                'is_active' => 'nullable|boolean',
            ]);
            
            // Check for duplicate name
            $slug = Str::slug($data['name']);
            $existingCategory = MusicCategory::where('slug', $slug)->first();
            
            if ($existingCategory) {
                return response()->json([
                    'message' => 'A category with this name already exists',
                    'errors' => [
                        'name' => ['The category name "' . $data['name'] . '" is already taken. Please use a different name.']
                    ]
                ], 422);
            }
            
            // Optional: Check for duplicate name with case-insensitive comparison
            $existingName = MusicCategory::whereRaw('LOWER(name) = ?', [strtolower($data['name'])])->first();
            if ($existingName) {
                return response()->json([
                    'message' => 'A category with a similar name already exists',
                    'errors' => [
                        'name' => ['Category "' . $existingName->name . '" already exists. Please use a different name.']
                    ]
                ], 422);
            }
            
            $data['slug'] = $slug;
            $category = MusicCategory::create($data);
            
            return response()->json([
                'message' => 'Category created successfully',
                'category' => $category->load('image')
            ], 201);
            
        } catch (\Illuminate\Database\QueryException $e) {
            // Handle database duplicate entry error (if unique constraint exists)
            if ($e->errorInfo[1] == 1062) { // MySQL duplicate entry error code
                return response()->json([
                    'message' => 'A category with this name already exists',
                    'errors' => [
                        'name' => ['The category name must be unique.']
                    ]
                ], 422);
            }
            
            return response()->json([
                'message' => 'An error occurred while creating the category',
                'error' => $e->getMessage()
            ], 500);
        }
    }
    
    public function show($id)
    {
        $category = MusicCategory::with(['image', 'playlists' => function($q) {
            $q->with(['image', 'musics' => function($q2) {
                $q2->where('music.is_active', true)->with('image')->orderBy('music_playlist.order');
            }])->where('is_active', true)->orderBy('order');
        }])->findOrFail($id);
        
        return response()->json($category);
    }
    
    // Category with each of its sub-categories and that sub-category's playlists.
    public function grouped($id)
    {
        $category = MusicCategory::with([
            'image',
            'subcategories' => function ($q) {
                $q->orderBy('order')->with([
                    'image',
                    'playlists' => function ($p) {
                        $p->where('is_active', true)->with('image')->orderBy('order');
                    },
                ]);
            },
        ])->findOrFail($id);

        return response()->json([
            'category' => [
                'id' => $category->id,
                'title' => $category->name,
                'description' => $category->description,
                'image_url' => $category->image?->url,
                'type' => 'playlist',
            ],
            'sub_categories' => $category->subcategories->map(fn ($sub) => [
                'sub_category' => [
                    'id' => $sub->id,
                    'title' => $sub->name,
                    'description' => $sub->description,
                    'image_url' => $sub->image?->url,
                ],
                'playlists' => $sub->playlists,
            ])->values(),
        ]);
    }

    public function update(Request $request, $id)
    {
        $category = MusicCategory::findOrFail($id);
        
        $data = $request->validate([
            'name' => 'sometimes|string|max:255',
            'description' => 'nullable|string',
            'image_id' => 'nullable|exists:images,id',
            'order' => 'nullable|integer',
            'is_active' => 'nullable|boolean',
        ]);
        
        if (isset($data['name'])) {
            $data['slug'] = Str::slug($data['name']);
        }
        
        $category->update($data);
        
        return response()->json([
            'message' => 'Category updated successfully',
            'category' => $category->load('image')
        ]);
    }
    
    public function destroy($id)
    {
        $category = MusicCategory::findOrFail($id);
        $category->delete();
        
        return response()->json(['message' => 'Category deleted successfully']);
    }


}