Fix Missing Alt Text in WordPress Automatically (Bulk + Auto Method)

				
					/**
 * ODesigning - Missing Image Alt Text Helper
 * Safe version for Woodmart child theme functions.php
 */

/**
 * Generate clean alt text from attachment title
 */
function odesigning_generate_clean_alt_from_title( $attachment_id ) {
    $title = get_the_title( $attachment_id );

    if ( empty( $title ) ) {
        return '';
    }

    // Remove common image extensions from title if present
    $title = preg_replace( '/\.(jpg|jpeg|png|gif|webp|svg|avif)$/i', '', $title );

    // Replace separators with spaces
    $title = str_replace( array( '-', '_', '.' ), ' ', $title );

    // Remove extra spaces
    $title = preg_replace( '/\s+/', ' ', $title );
    $title = trim( $title );

    return $title;
}

/**
 * Frontend fallback:
 * If image alt is empty, use attachment title as alt
 * Does not overwrite saved alt text
 */
function odesigning_set_missing_image_alt_clean( $attr, $attachment, $size ) {
    $existing_alt = get_post_meta( $attachment->ID, '_wp_attachment_image_alt', true );

    if ( empty( trim( (string) $existing_alt ) ) ) {
        $generated_alt = odesigning_generate_clean_alt_from_title( $attachment->ID );
        $attr['alt']   = $generated_alt;
    }

    return $attr;
}
add_filter( 'wp_get_attachment_image_attributes', 'odesigning_set_missing_image_alt_clean', 10, 3 );

/**
 * Add submenu page under Media
 */
function odesigning_register_bulk_alt_update_submenu() {
    add_media_page(
        'Bulk Alt Update',
        'Bulk Alt Update',
        'manage_options',
        'odesigning-bulk-alt-update',
        'odesigning_render_bulk_alt_update_page'
    );
}
add_action( 'admin_menu', 'odesigning_register_bulk_alt_update_submenu' );

/**
 * Count images with missing alt text
 */
function odesigning_count_images_missing_alt() {
    global $wpdb;

    $count = $wpdb->get_var(
        "
        SELECT COUNT(p.ID)
        FROM {$wpdb->posts} p
        LEFT JOIN {$wpdb->postmeta} pm
            ON p.ID = pm.post_id
            AND pm.meta_key = '_wp_attachment_image_alt'
        WHERE p.post_type = 'attachment'
        AND p.post_mime_type LIKE 'image/%'
        AND p.post_status = 'inherit'
        AND (
            pm.meta_value IS NULL
            OR TRIM(pm.meta_value) = ''
        )
        "
    );

    return (int) $count;
}

/**
 * Run one batch update only
 */
function odesigning_run_bulk_alt_update_batch( $limit = 100 ) {
    global $wpdb;

    $limit = absint( $limit );

    if ( $limit < 1 ) {
        $limit = 100;
    }

    $image_ids = $wpdb->get_col(
        $wpdb->prepare(
            "
            SELECT p.ID
            FROM {$wpdb->posts} p
            LEFT JOIN {$wpdb->postmeta} pm
                ON p.ID = pm.post_id
                AND pm.meta_key = '_wp_attachment_image_alt'
            WHERE p.post_type = 'attachment'
            AND p.post_mime_type LIKE 'image/%'
            AND p.post_status = 'inherit'
            AND (
                pm.meta_value IS NULL
                OR TRIM(pm.meta_value) = ''
            )
            ORDER BY p.ID ASC
            LIMIT %d
            ",
            $limit
        )
    );

    $updated = 0;
    $skipped = 0;

    if ( ! empty( $image_ids ) ) {
        foreach ( $image_ids as $image_id ) {
            $existing_alt = get_post_meta( $image_id, '_wp_attachment_image_alt', true );

            if ( ! empty( trim( (string) $existing_alt ) ) ) {
                $skipped++;
                continue;
            }

            $new_alt = odesigning_generate_clean_alt_from_title( $image_id );

            if ( '' !== $new_alt ) {
                update_post_meta( $image_id, '_wp_attachment_image_alt', $new_alt );
                $updated++;
            } else {
                $skipped++;
            }
        }
    }

    $remaining = odesigning_count_images_missing_alt();

    return array(
        'updated'   => $updated,
        'skipped'   => $skipped,
        'remaining' => $remaining,
    );
}

/**
 * Render admin page under Media
 */
function odesigning_render_bulk_alt_update_page() {
    if ( ! current_user_can( 'manage_options' ) ) {
        return;
    }

    $result = null;

    if (
        isset( $_POST['odesigning_run_bulk_alt_update_batch'] ) &&
        isset( $_POST['odesigning_bulk_alt_nonce'] ) &&
        wp_verify_nonce(
            sanitize_text_field( wp_unslash( $_POST['odesigning_bulk_alt_nonce'] ) ),
            'odesigning_bulk_alt_action'
        )
    ) {
        $result = odesigning_run_bulk_alt_update_batch( 100 );
    }

    $missing_count = odesigning_count_images_missing_alt();
    ?>
    <div class="wrap">
        <h1>Bulk Alt Update</h1>
        <p>This tool fills missing image alt text using the attachment title.</p>
        <p><strong>Only images with empty alt text are updated.</strong> Existing alt text will not be changed.</p>

        <hr>

        <p><strong>Images currently missing alt text:</strong> <?php echo esc_html( $missing_count ); ?></p>

        <?php if ( $result ) : ?>
            <div class="notice notice-success is-dismissible">
                <p><strong>Batch completed successfully.</strong></p>
                <p>Updated: <?php echo esc_html( $result['updated'] ); ?></p>
                <p>Skipped: <?php echo esc_html( $result['skipped'] ); ?></p>
                <p>Remaining: <?php echo esc_html( $result['remaining'] ); ?></p>
            </div>
        <?php endif; ?>

        <form method="post">
            <?php wp_nonce_field( 'odesigning_bulk_alt_action', 'odesigning_bulk_alt_nonce' ); ?>
            <p>
                <input type="submit" name="odesigning_run_bulk_alt_update_batch" class="button button-primary" value="Run Batch Update (100 Images)">
            </p>
        </form>
    </div>
    <?php
}