<?php

namespace FluentCommunity\Modules\Course\Http\Controllers;

use FluentCommunity\App\Http\Controllers\Controller;
use FluentCommunity\App\Models\SpaceUserPivot;
use FluentCommunity\App\Services\LockscreenService;
use FluentCommunity\Framework\Http\Request\Request;
use FluentCommunity\Modules\Course\Model\Course;
use FluentCommunity\Modules\Course\Model\CourseLesson;
use FluentCommunity\Modules\Course\Model\CourseTopic;
use FluentCommunity\Modules\Course\Services\CourseHelper;

class CourseController extends Controller
{
    public function getCourses(Request $request)
    {
        $user = $this->getUser();
        $isCourseCreator = $user && $user->hasCourseCreatorAccess();

        if ($request->get('type') == 'enrolled') {
            $courses = Course::searchBy($request->get('search'))
                ->where('status', 'published')
                ->orderBy('title', 'ASC')
                ->byPostTopic($request->get('topic_slug'))
                ->whereIn('id', CourseHelper::getEnrolledCourseIds())
                ->paginate();
        } else {
            $courses = Course::searchBy($request->get('search'))
                ->when(!$isCourseCreator, function ($q) {
                    $q->where('status', 'published');
                })
                ->byPostTopic($request->get('topic_slug'))
                ->orderBy('title', 'ASC')
                ->where(function ($q) {
                    $q->whereIn('privacy', ['public', 'private']);
                    if ($enrolledIds = CourseHelper::getEnrolledCourseIds()) {
                        $q->orWhereIn('id', $enrolledIds);
                    }
                })
                ->paginate();
        }


        foreach ($courses as $course) {
            $course->isEnrolled = CourseHelper::isEnrolled($course->id);
            if ($course->isEnrolled) {
                $course->progress = CourseHelper::getCourseProgress($course->id);
            }

            if (!$course->cover_photo) {
                $course->cover_photo = FLUENT_COMMUNITY_PLUGIN_URL . 'assets/images/course-placeholder.jpg';
            }

            $course->sectionsCount = CourseTopic::where('space_id', $course->id)->count();
            $course->lessonsCount = CourseLesson::where('space_id', $course->id)->count();
            $course->studentsCount = SpaceUserPivot::where('space_id', $course->id)->count();
        }

        return [
            'courses'           => $courses,
            'course_categories' => $request->get('with_categories') ?  CourseHelper::getCourseCategories() : []
        ];
    }

    public function getCourse(Request $request, $courseId)
    {
        $user = $this->getUser();
        $isCourseCreator = $user && $user->hasCourseCreatorAccess();

        $course = Course::when(!$isCourseCreator, function ($q) {
            $q->where('status', 'published');
        })->find($courseId);

        if (!$course) {
            return $this->sendError([
                'message' => 'Course not found. maybe the course is not published yet!'
            ]);
        }

        return $this->processCourse($course, $isCourseCreator);
    }

    public function getCourseBySlug(Request $request, $slug)
    {
        $user = $this->getUser();
        $isCourseCreator = $user && $user->hasCourseCreatorAccess();

        $course = Course::when(!$isCourseCreator, function ($q) {
            $q->where('status', 'published');
        })->where('slug', $slug)->firstOrFail();

        if (!$course) {
            return $this->sendError([
                'message' => 'Course not found. maybe the course is not published yet!'
            ]);
        }

        return $this->processCourse($course, $isCourseCreator);
    }

    private function processCourse($course, $isCourseCreator)
    {
        $sections = CourseTopic::where('space_id', $course->id)
            ->orderBy('priority', 'ASC')
            ->with(['lessons' => function ($query) use ($isCourseCreator) {
                if (!$isCourseCreator) {
                    $query->where('status', 'published');
                }
            }])
            ->get();

        $enrollment = CourseHelper::getCourseEnrollment($course->id);
        $formattedSections = [];

        if ($course->privacy == 'private' && !$enrollment) {
            $course->lockscreen_config = LockscreenService::getLockscreenConfig($course);
        }

        if ($course->privacy == 'secret' && !$enrollment && !$isCourseCreator) {
            return $this->sendError([
                'message' => 'You must need to be invited to view this course'
            ]);
        }

        $courseType = $course->getCourseType();

        foreach ($sections as $section) {
            if ($section->lessons->isEmpty()) {
                continue;
            }

            $hasAcessSectionAcess = !!$enrollment;
            $unlockDate = '';

            if ($hasAcessSectionAcess) {
                $unlockDate = CourseHelper::getSectionAccessDate($section, $courseType, $enrollment);
                if (!$unlockDate || strtotime($unlockDate) > current_time('timestamp')) {
                    $hasAcessSectionAcess = false;
                } else {
                    $unlockDate = null;
                }
            }

            $formattedLessons = [];
            foreach ($section->lessons as $lesson) {
                if ($hasAcessSectionAcess || $isCourseCreator) {
                    $content = $lesson->message_rendered;
                    if (!$content && $lesson->message) {
                        $content = apply_filters('widget_block_content', do_blocks($lesson->message));
                    }
                } else {
                    $content = '';
                }

                $formattedLessons[] = [
                    'id'             => $lesson->id,
                    'title'          => $lesson->title,
                    'content'        => $content,
                    'slug'           => $lesson->slug,
                    'course_id'      => $lesson->space_id,
                    'section_id'     => $lesson->parent_id,
                    'created_at'     => $lesson->created_at,
                    'meta'           => $lesson->meta,
                    'comments_count' => $lesson->comments_count,
                    'is_locked'      => !$hasAcessSectionAcess && !$isCourseCreator,
                    'unclock_date'   => $unlockDate
                ];
            }

            $formattedSections[] = [
                'id'          => $section->id,
                'title'       => $section->title,
                'lessons'     => $formattedLessons,
                'created_at'  => $section->created_at,
                'slug'        => $section->slug,
                'type'        => 'section',
                'is_locked'   => !$hasAcessSectionAcess && !$isCourseCreator,
                'unlock_date' => $unlockDate
            ];
        }

        return [
            'course'   => $course,
            'sections' => $formattedSections,
            'track'    => CourseHelper::getCourseProgressTrack($course->id)
        ];
    }

    public function enrollCourse(Request $request, $courseId)
    {
        $user = $this->getUser();

        if (!$user) {
            return $this->sendError([
                'message' => __('You need to login to enroll in this course.', 'fluent-community')
            ]);
        }

        $isCourseCreator = $user->hasCourseCreatorAccess();
        $course = Course::when(!$isCourseCreator, function ($q) {
            $q->where('status', 'published');
        })->findOrFail($courseId);


        if (!$isCourseCreator && $course->privacy != 'public') {
            return $this->sendError([
                'message' => __('You are not allowed to enroll in this course.', 'fluent-community')
            ]);
        }

        $enrolled = CourseHelper::enrollCourse($course, get_current_user_id());

        if (!$enrolled) {
            return [
                'message' => __('You are already enrolled in this course.', 'fluent-community'),
                'track'   => CourseHelper::getCourseProgressTrack($courseId)
            ];
        }

        return [
            'message' => __('You have been enrolled in this course.', 'fluent-community'),
            'track'   => CourseHelper::getCourseProgressTrack($courseId)
        ];
    }

    public function updateCompletionLesson(Request $request, $courseId, $lessonId)
    {
        $course = Course::findOrFail($courseId);

        if ($course->status != 'published') {
            return $this->sendError([
                'message' => __('Course is not in published state.', 'fluent-community')
            ]);
        }


        if (!CourseHelper::isEnrolled($courseId)) {
            return $this->sendError([
                'message' => 'You are not enrolled in this action.'
            ]);
        }

        $lesson = CourseLesson::where('space_id', $courseId)
            ->where('status', 'published')
            ->where('id', $lessonId)
            ->first();

        if (!$lesson) {
            return $this->sendError([
                'message' => 'Lesson is not on published state.'
            ]);
        }

        $state = $request->get('state');

        if (!in_array($state, ['completed', 'incomplete'])) {
            return $this->sendError([
                'message' => 'Invalid state.'
            ]);
        }

        CourseHelper::updateLessonCompletion($lesson, get_current_user_id(), $state);
        $track = CourseHelper::getCourseProgressTrack($courseId);
        $isCompleted = $track['progress'] == 100;

        if ($isCompleted) {
            CourseHelper::completeCourse($course, get_current_user_id());
        }

        return [
            'message'      => 'Lesson completion state updated.',
            'track'        => $track,
            'is_completed' => $isCompleted
        ];
    }
}