add.php

<?php

require_once('helpers.php');
require_once('init.php');
if (!isset($user_id)) {
    header('Location: index.php');
    exit();
}

$project_id = filter_input(INPUT_GET, 'id');
$projects_ids = [];
$projects = projects_db($connect, $user_id);
$projects_ids = array_column($projects, 'id');

$page_content = include_template('add.php', ['projects' => $projects]);

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $required = ['name', 'project_id'];
    $errors = [];

    $rules = [
        'name' => function ($value) {
            return required($value);
        },
        'project_id' => function ($value) use ($projects_ids) {
            return valid_projects($value, $projects_ids);
        },
        'deadline_at' => function ($value) {
            return valid_date($value);
        },
    ];

    $task = filter_input_array(INPUT_POST, ['name' => FILTER_DEFAULT, 'project_id' => FILTER_DEFAULT, 'deadline_at' => FILTER_DEFAULT], true);
    if (empty($task['deadline_at'])) {
        $task['deadline_at'] = null;
    }
    foreach ($task as $key => $value) {
        if (isset($rules[$key])) {
            $rule = $rules[$key];
            $errors[$key] = $rule($value);
        }
    }
    $errors = array_filter($errors);

    $task['user_id'] = $user_id;

    if (!empty($_FILES['file']['name'])) {
        $file_name = $_FILES['file']['name'];
        $file_path = __DIR__ . '/uploads/';
        $file_url = '/uploads/' . $file_name;
        $task['file'] = $file_name;
        move_uploaded_file($_FILES['file']['tmp_name'], $file_path . $file_name);
    } else {
        $task['file'] = null;
    }

    if (count($errors)) {
        $page_content = include_template(
            'add.php',
            [
                'projects' => $projects,
                'project_id' => $project_id,
                'task' => $task,
                'errors' => $errors,
            ]
        );
    } else {
        $sql = 'INSERT INTO tasks (created_at, name, project_id, deadline_at, user_id, file) VALUES (NOW(), ?, ?, ?, ?, ?)';
        execute_or_error($connect, $sql, $task);
        header('Location: index.php');
    }
}
$layout_content = include_template(
    'layout.php',
    [
        'content' => $page_content,
        'title' => 'Дела в порядке',
        'user' => $user_name,
    ]
);
print($layout_content);