<?php

namespace App\Http\Controllers;

use App\Models\Certificate;
use App\Models\Course;
use App\Models\Enrollment;
use App\Models\Forum;
use App\Models\Lesson;
use App\Models\Watch_history;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Session;
use Illuminate\Support\Facades\Log;

class PlayerController extends Controller
{
    public function reload_sidebar($course_id, $lesson_id)
    {
        $course_details = Course::findOrFail($course_id);
        $lesson_details = Lesson::findOrFail($lesson_id);

        return view('course_player.side_bar', compact(
            'course_details',
            'lesson_details'
        ));
    }

    public function course_player(Request $request, $slug, $id = '')
    {
        $course = Course::where('slug', $slug)->firstOrNew();

        // check if course is paid
        if ($course->is_paid && auth()->user()->role != 'admin') {
            if (auth()->user()->role == 'student') { // for student check enrollment status
                $enroll_status = enroll_status($course->id, auth()->user()->id);
                if ($enroll_status == 'expired') {
                    Session::flash('error', get_phrase('Your course accessibility has expired. You need to buy it again'));
                    return redirect()->route('course.details', ['slug' => $slug]);
                } elseif(! $enroll_status) {
                    Session::flash('error', get_phrase('Not registered for this course.'));
                    return redirect()->route('course.details', ['slug' => $slug]);
                }
            } elseif (auth()->user()->role == 'instructor') { // for instructor check who is course instructor
                if ($course->user_id != auth()->user()->id) {
                    Session::flash('error', get_phrase('Not valid instructor.'));
                    return redirect()->route('my.courses');
                }
            }
        }
        //cek histori tontonan
        $check_lesson_history = Watch_history::where('course_id', $course->id)
            ->where('student_id', auth()->user()->id)->first();
        $first_lesson_of_course = Lesson::where('course_id', $course->id)->orderBy('section_id', 'asc')->value('id');
        if ($id == '') {
            $id = $check_lesson_history->watching_lesson_id ?? $first_lesson_of_course;
        }


        // if user has any watched history or not
        if (! $check_lesson_history && $id > 0) {
            $data = [
                'course_id'          => $course->id,
                'student_id'         => auth()->user()->id,
                'watching_lesson_id' => $id,
                'completed_lesson'   => json_encode([])
            ];
            Watch_history::insert($data);
        }

        // when user plays a lesson, update that lesson id as watch history
        if ($id > 0) {
            Watch_history::where('course_id', $course->id)
                ->where('student_id', auth()->user()->id)
                ->update(['watching_lesson_id' => $id]);
        }

        $page_data['course_details'] = $course;
        $page_data['lesson_details'] = Lesson::where('id', $id)->firstOrNew();
        $page_data['history']        = Watch_history::where('course_id', $course->id)->where('student_id', auth()->user()->id)->first();

        $forum_query = Forum::join('users', 'forums.user_id', 'users.id')
            ->select('forums.*', 'users.name as user_name', 'users.photo as user_photo')
            ->latest('forums.id')
            ->where('forums.parent_id', 0)
            ->where('forums.course_id', $course->id);

        if (isset($_GET['search'])) {
            $forum_query->where(function ($query) use ($request) {
                $query->where('forums.title', 'like', '%' . $request->search . '%')->where('forums.description', 'like', '%' . $request->search . '%');
            });
        }

        $page_data['questions'] = $forum_query->get();

        return view('course_player.index', $page_data);
    }

    public function set_watch_history(Request $request)
    {
        $course     = Course::where('id', $request->course_id)->first();
        $enrollment = Enrollment::where('course_id', $course->id)->where('user_id', auth()->user()->id)->first();
        if (! $enrollment && (auth()->user()->role != 'admin' || ! is_course_instructor($course->id))) {
            Session::flash('error', get_phrase('Not registered for this course.'));
            return redirect()->back();
        }

        $data['course_id']  = $request->course_id;
        $data['student_id'] = auth()->user()->id;

        $total_lesson = Lesson::where('course_id', $request->course_id)->pluck('id')->toArray();
        $watch_history = Watch_history::where('course_id', $request->course_id)->where('student_id', auth()->user()->id)->first();
        $student_id = auth()->user()->id;
            
        if (isset($watch_history) && $watch_history->id) {
            $completed_lessons = [];
            if (!empty($watch_history->completed_lesson)) {
                $decoded = json_decode($watch_history->completed_lesson, true);
                if (is_array($decoded)) {
                    $completed_lessons = array_map('intval', $decoded);
                } else {
                    // Fallback jika format tidak valid
                    $completed_lesson_data = trim($watch_history->completed_lesson, '[]"\' ');
                    if (!empty($completed_lesson_data)) {
                        $completed_lessons = array_map('intval', explode(',', $completed_lesson_data));
                    }
                }
            }
            
            $completed_lessons = array_unique($completed_lessons);
            sort($completed_lessons);
            
            $lesson_id_int = (int)$request->lesson_id;
            if (!in_array($lesson_id_int, $completed_lessons)) {
                $completed_lessons[] = $lesson_id_int;
                sort($completed_lessons);
            }
            
            $data['completed_lesson']   = json_encode($completed_lessons);
            $data['watching_lesson_id'] = $lesson_id_int;
            
            Log::info('Updated lessons (integer array):', $completed_lessons);
            
            Watch_history::where('course_id', $request->course_id)
                        ->where('student_id', $student_id) 
                        ->update($data);
        } else {
            $lesson_id_int = (int)$request->lesson_id;
            $completed_lessons = [$lesson_id_int];       
            
            $data['completed_lesson']   = json_encode($completed_lessons);
            $data['watching_lesson_id'] = $lesson_id_int;
            
            Log::info('New lessons (integer array):', $completed_lessons);
            
            Watch_history::create($data);
        }
        
        // **LOGIKA SERTIFIKAT - dengan progress yang benar**
        $completed_lessons = $completed_lessons ?? [];
        $completed_in_course = array_intersect($completed_lessons, $total_lesson);
        $completed_count = count($completed_in_course);
        $total_count = count($total_lesson);
        
        $progress_percentage = 0;
        if ($total_count > 0) {
            $progress_percentage = ($completed_count / $total_count) * 100;
        }
         Log::info('Progress percentage: ' . $progress_percentage);
        // Jika progress 100% dan status project diterima, buat sertifikat
        if ($progress_percentage >= 100) {
            $certificateExists = Certificate::where('user_id', $student_id)
                ->where('course_id', $request->course_id)
                ->exists();

            if (!$certificateExists) {
                if (method_exists($this, 'generateIdentifier')) {
                    $identifier = $this->generateIdentifier(12);
                } else {
                    $identifier = \Illuminate\Support\Str::random(12);
                }
                
                Certificate::create([
                    'user_id'    => $student_id,
                    'course_id'  => $request->course_id,
                    'identifier' => $identifier,
                ]);
            }
        }


        return redirect()->back();
    }

    private function generateIdentifier($length = 12) 
    {
        $characters = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
        $charactersLength = strlen($characters);
        $randomString = '';
        
        for ($i = 0; $i < $length; $i++) {
            $randomString .= $characters[rand(0, $charactersLength - 1)];
        }
        
        return $randomString;
    }


    public function prepend_watermark()
    {
        return view('course_player.watermark');
    }
}