<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Illuminate\Http\JsonResponse;
use Illuminate\Support\Facades\Validator;

class TaskController extends Controller
{
    /**
     * Display a listing of tasks
     */
    public function index(): JsonResponse
    {
        // Sample data - in real app, this would come from database
        $tasks = [
            [
                'id' => 1,
                'text' => 'Project Planning',
                'start_date' => '2024-01-01',
                'duration' => 5,
                'progress' => 100,
                'priority' => 'high',
                'notes' => 'Initial project planning and requirements gathering',
                'parent' => null
            ],
            [
                'id' => 2,
                'text' => 'Design Phase',
                'start_date' => '2024-01-06',
                'duration' => 10,
                'progress' => 60,
                'priority' => 'medium',
                'notes' => 'UI/UX design and wireframing',
                'parent' => null
            ],
            [
                'id' => 3,
                'text' => 'Development',
                'start_date' => '2024-01-16',
                'duration' => 15,
                'progress' => 30,
                'priority' => 'high',
                'notes' => 'Core development work',
                'parent' => null
            ],
            [
                'id' => 4,
                'text' => 'Testing',
                'start_date' => '2024-01-31',
                'duration' => 7,
                'progress' => 0,
                'priority' => 'medium',
                'notes' => 'Quality assurance and testing',
                'parent' => null
            ],
            [
                'id' => 5,
                'text' => 'Deployment',
                'start_date' => '2024-02-07',
                'duration' => 3,
                'progress' => 0,
                'priority' => 'critical',
                'notes' => 'Production deployment and launch',
                'parent' => null
            ],
            [
                'id' => 6,
                'text' => 'Frontend Development',
                'start_date' => '2024-01-16',
                'duration' => 8,
                'progress' => 40,
                'priority' => 'high',
                'notes' => 'Vue.js frontend development',
                'parent' => 3
            ],
            [
                'id' => 7,
                'text' => 'Backend Development',
                'start_date' => '2024-01-24',
                'duration' => 7,
                'progress' => 20,
                'priority' => 'high',
                'notes' => 'Laravel backend development',
                'parent' => 3
            ]
        ];

        return response()->json([
            'success' => true,
            'data' => $tasks,
            'message' => 'Tasks retrieved successfully'
        ]);
    }

    /**
     * Store a newly created task
     */
    public function store(Request $request): JsonResponse
    {
        $validator = Validator::make($request->all(), [
            'text' => 'required|string|max:255',
            'start_date' => 'required|date',
            'duration' => 'required|integer|min:1',
            'priority' => 'required|in:low,medium,high,critical',
            'notes' => 'nullable|string',
            'parent' => 'nullable|integer'
        ]);

        if ($validator->fails()) {
            return response()->json([
                'success' => false,
                'message' => 'Validation failed',
                'errors' => $validator->errors()
            ], 422);
        }

        // In real app, save to database
        $task = [
            'id' => rand(1000, 9999), // Generate random ID for demo
            'text' => $request->text,
            'start_date' => $request->start_date,
            'duration' => $request->duration,
            'progress' => 0,
            'priority' => $request->priority,
            'notes' => $request->notes,
            'parent' => $request->parent
        ];

        return response()->json([
            'success' => true,
            'data' => $task,
            'message' => 'Task created successfully'
        ], 201);
    }

    /**
     * Display the specified task
     */
    public function show(int $id): JsonResponse
    {
        // Sample task data - in real app, fetch from database
        $task = [
            'id' => $id,
            'text' => 'Sample Task',
            'start_date' => '2024-01-01',
            'duration' => 5,
            'progress' => 50,
            'priority' => 'medium',
            'notes' => 'This is a sample task',
            'parent' => null
        ];

        return response()->json([
            'success' => true,
            'data' => $task,
            'message' => 'Task retrieved successfully'
        ]);
    }

    /**
     * Update the specified task
     */
    public function update(Request $request, int $id): JsonResponse
    {
        $validator = Validator::make($request->all(), [
            'text' => 'required|string|max:255',
            'start_date' => 'required|date',
            'duration' => 'required|integer|min:1',
            'priority' => 'required|in:low,medium,high,critical',
            'notes' => 'nullable|string',
            'parent' => 'nullable|integer'
        ]);

        if ($validator->fails()) {
            return response()->json([
                'success' => false,
                'message' => 'Validation failed',
                'errors' => $validator->errors()
            ], 422);
        }

        // In real app, update in database
        $task = [
            'id' => $id,
            'text' => $request->text,
            'start_date' => $request->start_date,
            'duration' => $request->duration,
            'progress' => $request->progress ?? 0,
            'priority' => $request->priority,
            'notes' => $request->notes,
            'parent' => $request->parent
        ];

        return response()->json([
            'success' => true,
            'data' => $task,
            'message' => 'Task updated successfully'
        ]);
    }

    /**
     * Remove the specified task
     */
    public function destroy(int $id): JsonResponse
    {
        // In real app, delete from database
        
        return response()->json([
            'success' => true,
            'message' => 'Task deleted successfully'
        ]);
    }
}