<?php
if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

class QEPW_Admin {
    public static function init() {
        add_action( 'admin_menu', [ self::class, 'add_admin_menu' ] );
        add_action( 'admin_init', [ self::class, 'register_settings' ] );
    }

    public static function add_admin_menu() {
        add_options_page(
            'Quick Embed PDF Settings',
            'Quick Embed PDF',
            'manage_options',
            'qepw',
            [ self::class, 'settings_page' ]
        );
    }

    public static function register_settings() {
        register_setting(
            'qepw_settings',
            'qepw_width',
            [
                'type'              => 'integer',
                'sanitize_callback' => 'absint',
                'default'           => 800,
            ]
        );

        register_setting(
            'qepw_settings',
            'qepw_download_button',
            [
                'type'              => 'boolean',
                'sanitize_callback' => 'rest_sanitize_boolean',
                'default'           => true,
            ]
        );
    }

    public static function render_usage_instructions() {
        ?>
        <div>
            <h3>1. Embedding in Classic Editor</h3>
            <p>To embed a PDF file in a post or page using the plugin, use the following shortcode. Example:</p>
            <code>[qepw_pdf_viewer file="YOUR_PDF_FILE_URL"]</code>
            <p>Replace <code>YOUR_PDF_FILE_URL</code> with the actual URL of your PDF file.</p>

            <h3>2. Embedding in Gutenberg Editor</h3>
            <p>In the Gutenberg editor, use the "Quick Embed PDF" block. It is available in the "Embed" category in the block menu. After adding the block, select a PDF from your media library or upload a new one.</p>

            <h3>3. Manually Embedding the Shortcode</h3>
            <p>If you want to manually embed a PDF file at any place in the content, use the following shortcode:</p>
            <code>[qepw_pdf_viewer file="YOUR_PDF_FILE_URL"]</code>
            <p>Replace <code>YOUR_PDF_FILE_URL</code> with the link to your PDF file.</p>
        </div>
        <?php
    }

    public static function settings_page() {
        ?>
        <div class="wrap">
            <h1>Quick Embed PDF Settings</h1>
            <form method="post" action="options.php">
                <?php
                settings_fields( 'qepw_settings' );
                ?>
                <table class="form-table">
                    <tr>
                        <th scope="row">Block Width (px)</th>
                        <td>
                            <input type="text"
                                   name="qepw_width"
                                   value="<?php echo esc_attr( get_option( 'qepw_width', 800 ) ); ?>"
                                   pattern="[0-9]*"
                                   required />
                        </td>
                    </tr>
                    <tr>
                        <th scope="row">Show Download Button</th>
                        <td>
                            <input type="checkbox"
                                   name="qepw_download_button"
                                   value="1"
                                   <?php checked( get_option( 'qepw_download_button', true ), true ); ?> />
                        </td>
                    </tr>
                </table>
                <?php submit_button(); ?>
            </form>

            <h2>Plugin Usage</h2>
            <div>
                <?php self::render_usage_instructions(); ?>
            </div>
        </div>
        <?php
    }
}