<?php

namespace App\Http\Controllers;

use App\Models\Course;
use App\Models\CourseInfo;
use App\Models\Instructor;
use App\Models\Section;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Validator;
use Illuminate\Support\Str;

class PublishController extends Controller
{
    public function approveCourse(Request $request)
    {
        $validator = Validator::make($request->all(), [
            'course_id' => ['required', 'exists:courses,id'],
        ]);
        if ($validator->fails()) {
            return response(
                [
                    'errors' => $validator->errors()->all()],
                422
            );
        }
        $courses = Course::where('id', (int)$request->course_id)->update(['published' => 1]);
        return response([
            'message' => 'Course has been approved successfully',
        ], 200);
    }

    public function fetchCoursesUnderReview()
    {
        $courses = Course::
        with(['user:id,firstname,lastname'])
            ->where(['published' => 5])
            ->orderby('updated_at', 'desc')
            ->paginate(150);
        return response([
            'data' => $courses,
        ], 200);
    }


    public function publishCourse(Request $request)
    {
        $val = Validator::make($request->all(), [
            'slug' => 'required|exists:courses,slug',
        ]);

        if ($val->fails()) {
            return response(['errors' => $val->errors()->all()], 422);
        }
        $course = Course::where('slug', $request->slug)->first();
        $user = auth()->user();

        // if($course->published > 0) {
        //     return response([
        //         'message' => 'You can not resubmit this course for update'
        //     ], 400);
        // }


        if ($course->user_id != $user->id) {
            return response(['message' => 'You are trying to upload a course that does not belong to you'], 401);
        }

        $sections_err = $this->checkLectures($course->id)['errors'];
        $info_err = $this->checkCourseInfo($course->id)['errors'];
        $pro_err = $this->checkInstructorProfile($course->user_id)['errors'];
        $cou_err = $this->checkCourse($course->id)['errors'];


        $total_err = array_merge($info_err, $pro_err);
        $total_err = array_merge($cou_err, $total_err);
        $total_err = array_merge($sections_err, $total_err);

        if (count($total_err) == 0) {
            $course->published = 5 ;
            $course->save();

            return response([
                'message' => 'Your course has been submitted for review',
            ], 200);
        }


        return response([
            'message' => 'You cannot publish this course because some requirements have not been met',
            'errors' => $total_err,
        ], 400);
    }


    public function checkLectures($course_id)
    {
        $course = Course::find($course_id);
        $sections = Section::where('course_id', $course_id)->get();
        $errs = [];
        if (count($sections) < 5) {
            $errs[] = 'You must have at least five topics in your curriculum';
        }
        $empty_lecture = 0;
        $empty_section = 0;

        foreach ($sections as $sec) {
            $lectures = $sec->lectures;
            if (count($lectures) == 0) {
                $empty_section++;
            }
            foreach ($lectures as $lec) {
                if ($lec->main_content == '' && $course->course_type !== 4) {
                    $empty_lecture++;
                }
            }
        }

        if ($empty_lecture > 0) {
            $errs[] = $empty_lecture . ' ' . Str::plural('lecture', $empty_lecture) . " " . Str::plural('is', $empty_lecture) . " without content";
        }
        if ($empty_section > 0) {
            $errs[] = $empty_section . " " . Str::plural('topic', $empty_section) . " " . Str::plural('is', $empty_section) . ' without lecture';
        }

        return [
            'errors' => $errs,
            'count' => count($errs),
        ];
    }

    function checkCourseInfo($course_id)
    {
        $info = CourseInfo::where(['course_id' => $course_id])->first();
        $errs = [];
        $what_you_learn = ($info->what_you_will_learn) ? count(json_decode($info->what_you_will_learn)) : 0;
        $requirement = ($info->course_requirement) ? count(json_decode($info->course_requirement)) : 0;
        $audience = ($info->course_audience) ? count(json_decode($info->course_audience)) : 0;
        $purpose = ($info->purpose) ? count(json_decode($info->purpose)) : 0;

        if ($what_you_learn < 4) {
            $errs[] = 'What student will learn from taking your course is less than four';
        }

        if ($requirement == 0) {
            $errs[] = 'Requirements for taking this course has not been uploaded';
        }

        if ($audience == 0) {
            $errs[] = 'There are no specified audience for this course';
        }

        if ($purpose == 0) {
            $errs[] = 'Purpose of taking the course is not stated';
        }

        if ($info->opportunities == '') {
            $errs[] = 'Please specify job opportunities available from taking your course';
        }

        return ['errors' => $errs, 'count' => count($errs)];
    }

    public function checkInstructorProfile($user_id)
    {
        $instructor = Instructor::where(['user_id' => $user_id])->first();
        $errs = [];
        if ($instructor->biography == '') {
            $errs[] = 'Biography has not been uploaded';
        }

        if ($instructor->headline == '') {
            $errs[] = 'Profile Headline has not been uploaded';
        }
        return ['errors' => $errs, 'count' => count($errs)];
    }

    public function checkCourse($course_id)
    {
        $course = Course::find($course_id);

        $errs = [];

        if ($course->video == '') {
            $errs[] = 'No course  promotional video found';
        }

        if ($course->image == '') {
            $errs[] = 'Course image not found';
        }

        if ($course->description == '') {
            $errs[] = 'Course description is too short';
        }

        if ($course->level == 0) {
            $errs[] = 'Please specify the course level';
        }

        if ($course->price == 0) {
            $errs[] = 'Price attached to course is too small';
        }

        if ($course->course_type == 4 && empty($course->book_name)) {
            $errs[] = 'Book has not been uploaded for this course';
        }

        return [
            'errors' => $errs,
            'count' => count($errs),
        ];
    }


    public function publishedStatus($status)
    {
        if ($status = 0) {
            $val = 'Newly Created';
        } elseif ($status == 1) {
        } elseif ($status == 5) {
            $val = 'Under Review';
        }
    }
}