<?php

include("includes/config.php");

if(isset($_POST['add_course'])){
    $course = $_POST['course'];	
    $description = $_POST['description'];
    $link = $_POST['link'];

    $photo = $_FILES['photo']['name'];

    $course = mysqli_real_escape_string($conn, $course);
    $description = mysqli_real_escape_string($conn, $description);
    $link = mysqli_real_escape_string($conn, $link);

    $query = "INSERT INTO `courses` (`course`,`description` ,`link`, `photo`) VALUES ('$course','$description','$link', '$photo')";
    $query_run = mysqli_query($conn, $query);

    if($query_run){
        move_uploaded_file($_FILES["photo"]["tmp_name"], "course/".$_FILES["photo"]["name"]);
    
        $_SESSION['status'] = "Data Uploaded Successfully";
        header('Location: view-course.php');
        exit;
    } else {
        $_SESSION['status'] = "Data Not Uploaded Successfully";
        header('Location: course.php');
        exit;
    }
}



// update 
if(isset($_POST['update_course'])){
    $id = $_POST['id'];
    $course = $_POST['course'];	
    $description = $_POST['description'];
    $link = $_POST['link'];
    $old_photo = $_POST['image_old'];

    $course = mysqli_real_escape_string($conn, $course);
    $description = mysqli_real_escape_string($conn, $description);
    $link = mysqli_real_escape_string($conn, $link);
    $old_photo = mysqli_real_escape_string($conn, $old_photo);

    $update_photo_filename = $_FILES["photo"]["name"] ? $_FILES["photo"]["name"] : $old_photo;
    $allowed_image_extensions = array('gif','png','jpg','jpeg','webp','WEBP');
    $photo_file_extension = pathinfo($update_photo_filename, PATHINFO_EXTENSION);

    if(!in_array($photo_file_extension, $allowed_image_extensions)){
        $_SESSION['status'] = "The image file is not allowed. Please upload an image.";
        header("Location: edit-course.php?id=$id");
        exit;
    }
    

    $query = "UPDATE courses SET course='$course', description='$description', link='$link', photo='$update_photo_filename' WHERE id ='$id' ";
    $query_run = mysqli_query($conn, $query);

    if($query_run){
        if($_FILES["photo"]["name"] !='' && $_FILES["photo"]["name"] != $old_photo){
            move_uploaded_file($_FILES["photo"]["tmp_name"], "course/".$_FILES["photo"]["name"]);
            unlink("course/". $old_photo);    
        }
        $_SESSION['status'] = "Data Updated Successfully";
        header('Location: view-course.php');
    } else {
        $_SESSION['status'] = "Data Not Updated Successfully";
        header('Location: view-course.php');
    }
}

// delete

if(isset($_POST['delete_course'])){
    $id = $_POST['delete_id'];
    $photo = $_POST['del_course'];
    // $pdf = $_POST['del_pdf'];

    $query = "DELETE FROM courses WHERE id = '$id'";
    $query_run = mysqli_query($conn, $query);

    if($query_run){
        if(unlink("course/".$photo)) {
            $_SESSION['status'] = "Deleted Successfully";
            header('Location: view-course.php');
        } else {
            $_SESSION['status'] = "Error deleting files";
            header('Location: view-course.php');
        }
    } else {
        $_SESSION['status'] = "Not Deleted Successfully";
        header('Location: view-course.php');
    }
}
?>