<?php

namespace App\Http\Controllers\Admin;

use App\Http\Controllers\Controller;
use App\Models\Quiz;
use App\Models\QuizCategory;
use App\Models\QuizSubject;
use App\Models\Question;
use App\Models\QuestionOption;
use Illuminate\Http\Request;
use Illuminate\Support\Str;

class QuizController extends Controller
{
    public function index()
    {
        $quizzes = Quiz::with('category')->withCount('questions')->latest()->paginate(15);
        return view('admin.quizzes.index', compact('quizzes'));
    }

    public function create()
    {
        $categories = QuizCategory::where('is_active', true)->get();
        return view('admin.quizzes.create', compact('categories'));
    }

    public function store(Request $request)
    {
        $validated = $request->validate([
            'title' => 'required|string|max:255',
            'category_id' => 'required|exists:quiz_categories,id',
            'year' => 'nullable|integer',
            'type' => 'required|in:multiple_choice,descriptive,mixed',
            'duration_minutes' => 'required|integer|min:1',
            'has_negative_score' => 'boolean',
            'is_free' => 'boolean',
            'is_published' => 'boolean',
            'description' => 'nullable|string',
        ]);

        $validated['slug'] = Str::slug($validated['title']) . '-' . time();
        $validated['has_negative_score'] = $request->has('has_negative_score');
        $validated['is_free'] = $request->has('is_free');
        $validated['is_published'] = $request->has('is_published');

        $quiz = Quiz::create($validated);

        return redirect()->route('quizzes.questions.index', $quiz->id)
            ->with('success', 'آزمون با موفقیت ایجاد شد. اکنون می‌توانید سوالات را اضافه کنید.');
    }

    public function destroy(Quiz $quiz)
    {
        $quiz->delete();
        return redirect()->route('quizzes.index')->with('success', 'آزمون حذف شد.');
    }

    // --- Questions Management ---

    public function questions(Quiz $quiz)
    {
        $quiz->load(['questions.options', 'questions.subject']);
        $subjects = QuizSubject::all();
        return view('admin.quizzes.questions', compact('quiz', 'subjects'));
    }

    public function storeQuestion(Request $request, Quiz $quiz)
    {
        $request->validate([
            'question_text' => 'required|string',
            'type' => 'required|in:multiple_choice,descriptive',
            'subject_id' => 'nullable|exists:quiz_subjects,id',
            'score' => 'required|numeric|min:0.5',
            'solution_explanation' => 'nullable|string',
            // Options validation for multiple-choice questions
            'options' => 'required_if:type,multiple_choice|array|min:4|max:4',
            'options.*' => 'required_if:type,multiple_choice|string',
            'correct_option' => 'required_if:type,multiple_choice|integer|between:0,3',
        ]);

        $question = $quiz->questions()->create([
            'subject_id' => $request->subject_id,
            'question_text' => $request->question_text,
            'type' => $request->type,
            'score' => $request->score,
            'solution_explanation' => $request->solution_explanation,
            'order' => $quiz->questions()->count() + 1,
        ]);

        // Save options if question is multiple choice
        if ($request->type === 'multiple_choice' && $request->has('options')) {
            foreach ($request->options as $index => $optionText) {
                $question->options()->create([
                    'option_text' => $optionText,
                    'is_correct' => ($index == $request->correct_option),
                ]);
            }
        }

        return back()->with('success', 'سوال با موفقیت ثبت شد.');
    }

    public function destroyQuestion(Question $question)
    {
        $question->delete();
        return back()->with('success', 'سوال حذف شد.');
    }
}