<?php
/*
Plugin Name: Send User Notification Plugin
Description: Send Email/SMS Notification for bulk users 
Version: 1.0
Author: Itrosys
*/
function custom_email_admin_menu() {
    add_menu_page(
        'Send Email to Users',
        'Send Email',
        'manage_options',
        'send-email-users',
        'custom_email_admin_page',
        'dashicons-email-alt',
        100
    );
}
add_action('admin_menu', 'custom_email_admin_menu');

function custom_email_admin_page() {
    if (isset($_POST['send_email'])) {
        custom_send_email_to_users($_POST['user_ids'], $_POST['subject'], $_POST['message']);
    }

    $users = get_users();
    ?>
    <div class="wrap">
	<!-- Bootstrap 5 CSS -->
    <link href="https://maxcdn.bootstrapcdn.com/bootstrap/5.3.0/css/bootstrap.min.css" rel="stylesheet">
    <!-- Choices.js CSS -->
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/choices.js/public/assets/styles/choices.min.css">
        <h1>Send Notification to Users</h1>
        <form method="post">
            <table class="form-table">
                <tr valign="top">
                    <th scope="row">Select Users</th>
                    <td>
                        <select id="multi-select" class="form-select" name="user_ids[]" multiple>
                            <?php foreach ($users as $user) : ?>
                                <option value="<?php echo esc_attr($user->ID); ?>"><?php echo esc_html($user->display_name); ?></option>
                            <?php endforeach; ?>
                        </select>
                    </td>
                </tr>
                <tr valign="top">
                    <th scope="row">Subject</th>
                    <td>
                        <input type="text" name="subject" required style="width: 100%;">
                    </td>
                </tr>
                <tr valign="top">
                    <th scope="row">Message</th>
                    <td>
                        <textarea name="message" required style="width: 100%;" rows="10"></textarea>
                    </td>
                </tr>
            </table>
            <p class="submit">
                <input type="submit" name="send_email" class="button-primary" value="Send Email">
				<!-- <input type="submit" name="send_sms" class="button-primary" value="Send SMS"> -->
            </p>
        </form>
    </div>
	<!-- Bootstrap 5 JS -->
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/5.3.0/js/bootstrap.bundle.min.js"></script>
    <!-- Choices.js JS -->
    <script src="https://cdn.jsdelivr.net/npm/choices.js/public/assets/scripts/choices.min.js"></script>
    <script>
        document.addEventListener('DOMContentLoaded', function () {
            const element = document.getElementById('multi-select');
            const choices = new Choices(element, {
                removeItemButton: true,
                searchEnabled: true,
                shouldSort: false,
                placeholder: true,
                placeholderValue: 'Select an option',
            });
        });
    </script>
    <?php
}

function custom_send_email_to_users($user_ids, $subject, $message) {
    foreach ($user_ids as $user_id) {
        $user = get_userdata($user_id);
        if ($user) {
            $sendmail = wp_mail($user->user_email, $subject, $message);
			if($sendmail ){
				echo "Email sent successfully";
			}else{
				echo "Error Occurs!!!";
			}
        }else{
			echo "User is not available";
		}
    }
}

function hide_screen_options_for_notification() {
    ?>
    <style>
    <?php if (isset($_GET['page']) && ($_GET['page'] === 'send-email-users')) : ?>
        #screen-meta-links {
            display: none !important;
        }
    <?php endif; ?>
    </style>
    <?php
}
add_action('admin_head', 'hide_screen_options_for_notification');