<?php

namespace App\Controllers;

use App\Core\Request;
use App\Core\Response;
use App\Core\Database;
use App\Core\Security;
use App\Services\VideoService;

class VideoController
{
    /**
     * Upload Video directly via API and create/attach to Lesson
     * POST /api/teacher/videos/upload-direct
     */
    public function uploadDirect(Request $request, Response $response): void
    {
        VideoService::ensureSchema();

        $courseId = (int)($request->getBody()['course_id'] ?? $_POST['course_id'] ?? 0);
        $title    = trim((string)($request->getBody()['title'] ?? $_POST['title'] ?? ''));
        $seqOrder = (int)($request->getBody()['sequence_order'] ?? $_POST['sequence_order'] ?? 1);

        if (!$courseId || empty($title)) {
            $response->status(400)->json([
                'status'  => 'error',
                'message' => 'معرف الدورة وعنوان الدرس مطلوبان'
            ]);
            return;
        }

        // Verify Course Ownership
        $course = Database::selectOne("SELECT id, teacher_id FROM courses WHERE id = ? LIMIT 1", [$courseId]);
        if (!$course || ($course['teacher_id'] != $request->user_id && $request->role !== 'super_admin')) {
            $response->status(403)->json([
                'status'  => 'error',
                'message' => 'غير مصرح: لا تملك صلاحية التعديل على هذه الدورة'
            ]);
            return;
        }

        if (empty($_FILES['video'])) {
            $response->status(400)->json([
                'status'  => 'error',
                'message' => 'يرجى إرفاق ملف الفيديو في الطلب (key: video)'
            ]);
            return;
        }

        try {
            $uploadResult = VideoService::handleDirectUpload($_FILES['video'], $courseId, $title);

            // Insert lesson record with HLS references
            $lessonId = Database::insert(
                "INSERT INTO lessons (course_id, title, sequence_order, storage_type, video_uuid, bunny_video_id, local_path, hls_url, thumbnail_url, duration_seconds, is_free_preview, encoding_status) 
                 VALUES (?, ?, ?, 'api_upload', ?, '', ?, ?, ?, ?, 0, 'ready')",
                [
                    $courseId,
                    $title,
                    $seqOrder,
                    $uploadResult['video_uuid'],
                    $uploadResult['local_path'],
                    $uploadResult['hls_url'],
                    $uploadResult['thumbnail_url'],
                    $uploadResult['duration'] ?? 0
                ]
            );

            $response->status(201)->json([
                'status'  => 'success',
                'message' => 'تم رفع وحفظ ملف الفيديو وتقطيعه بتقنية HLS بنجاح!',
                'data'    => array_merge($uploadResult, [
                    'lesson_id' => $lessonId,
                    'title'     => $title,
                    'course_id' => $courseId
                ])
            ]);
        } catch (\Throwable $e) {
            $response->status(500)->json([
                'status'  => 'error',
                'message' => $e->getMessage()
            ]);
        }
    }

    /**
     * Create video entity on Bunny Stream
     * POST /api/teacher/videos/bunny-create
     */
    public function createBunnyVideo(Request $request, Response $response): void
    {
        VideoService::ensureSchema();

        $body = $request->getBody();
        $title = trim((string)($body['title'] ?? 'درس جديد'));
        $courseId = (int)($body['course_id'] ?? 0);

        if (!$courseId) {
            $response->status(400)->json(['status' => 'error', 'message' => 'معرف الدورة مطلوب']);
            return;
        }

        try {
            $result = VideoService::createBunnyVideo($title);
            $response->status(201)->json([
                'status'  => 'success',
                'message' => 'تم إنشاء الفيديو في Bunny Stream بنجاح',
                'data'    => $result
            ]);
        } catch (\Throwable $e) {
            $response->status(500)->json([
                'status'  => 'error',
                'message' => $e->getMessage()
            ]);
        }
    }

    /**
     * Link an existing or newly created Bunny Video ID to a Course Lesson
     * POST /api/teacher/videos/bunny-link
     */
    public function linkBunnyLesson(Request $request, Response $response): void
    {
        VideoService::ensureSchema();

        $body = $request->getBody();
        $courseId      = (int)($body['course_id'] ?? 0);
        $title         = trim((string)($body['title'] ?? ''));
        $bunnyVideoId  = trim((string)($body['bunny_video_id'] ?? ''));
        $duration      = (int)($body['duration_seconds'] ?? 0);
        $sequenceOrder = (int)($body['sequence_order'] ?? 1);

        if (!$courseId || empty($title) || empty($bunnyVideoId)) {
            $response->status(400)->json([
                'status'  => 'error',
                'message' => 'معرف الدورة، عنوان الدرس، ومعرف فيديو Bunny Stream مطلوبين'
            ]);
            return;
        }

        $course = Database::selectOne("SELECT id, teacher_id FROM courses WHERE id = ? LIMIT 1", [$courseId]);
        if (!$course || ($course['teacher_id'] != $request->user_id && $request->role !== 'super_admin')) {
            $response->status(403)->json([
                'status'  => 'error',
                'message' => 'غير مصرح: لا تملك هذه الدورة'
            ]);
            return;
        }

        $lessonId = Database::insert(
            "INSERT INTO lessons (course_id, title, sequence_order, storage_type, bunny_video_id, duration_seconds, is_free_preview, encoding_status) 
             VALUES (?, ?, ?, 'bunny_stream', ?, ?, 0, 'ready')",
            [$courseId, $title, $sequenceOrder, $bunnyVideoId, $duration]
        );

        $response->status(201)->json([
            'status'  => 'success',
            'message' => 'تم ربط درس Bunny Stream بنجاح!',
            'data'    => [
                'lesson_id'      => $lessonId,
                'bunny_video_id' => $bunnyVideoId,
                'storage_type'   => 'bunny_stream'
            ]
        ]);
    }

    /**
     * Stream Local Video via HTTP 206 Range Streaming
     * GET /api/videos/stream/{uuid}
     */
    public function streamLocalVideo(Request $request, Response $response): void
    {
        $uuid = $request->getParam('uuid');
        if (empty($uuid)) {
            $response->status(400)->json(['status' => 'error', 'message' => 'معرف الفيديو مطلوب']);
            return;
        }

        VideoService::streamLocalVideo($uuid);
    }

    /**
     * Stream HLS Playlist or Video Segments
     * GET /api/videos/hls/{uuid}/{file}
     */
    public function streamHls(Request $request, Response $response): void
    {
        $uuid = $request->getParam('uuid');
        $file = $request->getParam('file') ?: 'index.m3u8';

        if (empty($uuid)) {
            $response->status(400)->json(['status' => 'error', 'message' => 'معرف البث مطلوب']);
            return;
        }

        VideoService::streamHlsFile($uuid, $file);
    }

    /**
     * Save Socratic Checkpoint Quiz inside a Video Lesson
     * POST /api/teacher/lessons/checkpoints
     */
    public function saveCheckpoint(Request $request, Response $response): void
    {
        $body = $request->getBody();
        $lessonId    = (int)($body['lesson_id'] ?? 0);
        $timeSeconds = (int)($body['timestamp_seconds'] ?? 15);
        $rewindSecs  = (int)($body['rewind_seconds'] ?? 45);
        $question    = trim((string)($body['question_text'] ?? ''));
        $options     = (array)($body['options'] ?? []);
        $correctIdx  = (int)($body['correct_index'] ?? 0);

        if (!$lessonId || empty($question) || empty($options)) {
            $response->status(400)->json([
                'status'  => 'error',
                'message' => 'بيانات نقطة الفحص السقراطي والسؤال غير مكتملة'
            ]);
            return;
        }

        $lesson = Database::selectOne("SELECT l.id, l.course_id, c.teacher_id FROM lessons l JOIN courses c ON l.course_id = c.id WHERE l.id = ?", [$lessonId]);
        if (!$lesson || ($lesson['teacher_id'] != $request->user_id && $request->role !== 'super_admin')) {
            $response->status(403)->json(['status' => 'error', 'message' => 'غير مصرح: لا تملك هذا الدرس']);
            return;
        }

        $examUuid = sprintf('%04x%04x-%04x-%04x-%04x-%04x%04x%04x',
            mt_rand(0, 0xffff), mt_rand(0, 0xffff),
            mt_rand(0, 0xffff),
            mt_rand(0, 0x0fff) | 0x4000,
            mt_rand(0, 0x3fff) | 0x8000,
            mt_rand(0, 0xffff), mt_rand(0, 0xffff), mt_rand(0, 0xffff)
        );

        $examId = Database::insert(
            "INSERT INTO exams (uuid, course_id, lesson_id, created_by_id, creator_type, scope, title, timestamp_seconds, rewind_on_fail_seconds, passing_percentage, total_points, is_mandatory, is_published)
             VALUES (?, ?, ?, ?, 'teacher', 'in_video_checkpoint', 'فحص سقراطي لحظي', ?, ?, 100.00, 10, 1, 1)",
            [$examUuid, $lesson['course_id'], $lessonId, $request->user_id, $timeSeconds, $rewindSecs]
        );

        $qUuid = sprintf('%04x%04x-%04x-%04x-%04x-%04x%04x%04x',
            mt_rand(0, 0xffff), mt_rand(0, 0xffff),
            mt_rand(0, 0xffff),
            mt_rand(0, 0x0fff) | 0x4000,
            mt_rand(0, 0x3fff) | 0x8000,
            mt_rand(0, 0xffff), mt_rand(0, 0xffff), mt_rand(0, 0xffff)
        );

        $qId = Database::insert(
            "INSERT INTO questions (uuid, exam_id, question_text, question_type, bloom_taxonomy, points) VALUES (?, ?, ?, 'multiple_choice', 'comprehension', 10)",
            [$qUuid, $examId, $question]
        );

        foreach ($options as $idx => $optText) {
            $isCorrect = ($idx === $correctIdx) ? 1 : 0;
            Database::insert(
                "INSERT INTO question_options (question_id, option_text, is_correct) VALUES (?, ?, ?)",
                [$qId, $optText, $isCorrect]
            );
        }

        $response->status(201)->json([
            'status'  => 'success',
            'message' => 'تم حفظ وتثبيت نقطة الفحص السقراطي بنجاح!',
            'data'    => [
                'exam_id'           => $examId,
                'timestamp_seconds' => $timeSeconds,
                'question_id'       => $qId
            ]
        ]);
    }

    /**
     * Get Lesson Playback Data with Signed DRM Tokens and Socratic Checkpoints
     * GET /api/lessons/{id}/playback
     */
    public function getPlaybackData(Request $request, Response $response): void
    {
        VideoService::ensureSchema();

        $lessonId = (int)$request->getParam('id');
        if (!$lessonId) {
            $response->status(400)->json(['status' => 'error', 'message' => 'معرف الدرس مطلوب']);
            return;
        }

        $lesson = Database::selectOne("SELECT * FROM lessons WHERE id = ? LIMIT 1", [$lessonId]);
        if (!$lesson) {
            $response->status(404)->json(['status' => 'error', 'message' => 'الدرس غير موجود']);
            return;
        }

        // Fetch attached in-video Socratic Checkpoints with Questions and Options
        $exams = Database::select(
            "SELECT e.id as exam_id, e.uuid as exam_uuid, e.title, e.timestamp_seconds, e.rewind_on_fail_seconds, e.passing_percentage
             FROM exams e 
             WHERE e.lesson_id = ? AND e.scope = 'in_video_checkpoint' AND e.is_published = 1
             ORDER BY e.timestamp_seconds ASC",
            [$lessonId]
        );

        $checkpoints = [];
        foreach ($exams as $ex) {
            $q = Database::selectOne("SELECT id, question_text, explanation_text FROM questions WHERE exam_id = ? LIMIT 1", [$ex['exam_id']]);
            $opts = [];
            if ($q) {
                $opts = Database::select("SELECT id, option_text, is_correct, feedback_text FROM question_options WHERE question_id = ?", [$q['id']]);
            }

            $checkpoints[] = [
                'exam_id'                => (int)$ex['exam_id'],
                'timestamp_seconds'      => (int)$ex['timestamp_seconds'],
                'rewind_on_fail_seconds' => (int)$ex['rewind_on_fail_seconds'],
                'question_text'          => $q['question_text'] ?? 'ما هي الإجابة الصحيحة؟',
                'options'                => array_map(function ($o) {
                    return [
                        'id'         => (int)$o['id'],
                        'text'       => $o['option_text'],
                        'is_correct' => (bool)$o['is_correct']
                    ];
                }, $opts)
            ];
        }

        $storageType = $lesson['storage_type'] ?? 'bunny_stream';
        $playbackInfo = [];

        if ($storageType === 'api_upload') {
            $playbackInfo = [
                'storage_type' => 'api_upload',
                'stream_url'   => '/api/videos/stream/' . $lesson['video_uuid'],
                'hls_url'      => $lesson['hls_url'] ?: ('/api/videos/hls/' . $lesson['video_uuid'] . '/index.m3u8'),
                'video_uuid'   => $lesson['video_uuid'],
                'is_direct'    => true
            ];
        } else {
            // Bunny Stream Signed Playback
            $bunnyId = $lesson['bunny_video_id'] ?: 'mock-bunny-guid-2026';
            $signedData = VideoService::generateBunnySignedPlayback($bunnyId, 10800); // 3-hour token
            $playbackInfo = array_merge(['storage_type' => 'bunny_stream'], $signedData);
        }

        $response->json([
            'status' => 'success',
            'data'   => [
                'lesson'      => [
                    'id'               => (int)$lesson['id'],
                    'course_id'        => (int)$lesson['course_id'],
                    'title'            => $lesson['title'],
                    'duration_seconds' => (int)$lesson['duration_seconds'],
                    'is_free_preview'  => (bool)$lesson['is_free_preview'],
                    'storage_type'     => $storageType
                ],
                'playback'    => $playbackInfo,
                'checkpoints' => $checkpoints ?: []
            ]
        ]);
    }

    /**
     * Webhook listener for Bunny Stream encoding notifications
     * POST /api/webhooks/bunny
     */
    public function handleBunnyWebhook(Request $request, Response $response): void
    {
        VideoService::ensureSchema();

        $body = $request->getBody();
        $videoId = trim((string)($body['VideoGuid'] ?? $body['videoId'] ?? ''));
        $status  = (int)($body['Status'] ?? 0);

        if (!empty($videoId)) {
            $encodingStatus = ($status === 3) ? 'ready' : (($status === 4) ? 'failed' : 'processing');
            Database::query(
                "UPDATE lessons SET encoding_status = ? WHERE bunny_video_id = ?",
                [$encodingStatus, $videoId]
            );
        }

        $response->json(['status' => 'received']);
    }
}