From f7702f287226330e99f38bdbf8b27018c7acb1af Mon Sep 17 00:00:00 2001
From: Javier Casares
Date: Thu, 19 Feb 2026 11:15:55 +0000
Subject: [PATCH] v1.0.0
---
CHANGELOG.md | 38 +
LICENSE | 674 ++++++++++++++++
README.md | 132 ++++
admin/class-robotstxt-og-admin-settings.php | 733 ++++++++++++++++++
admin/views/settings-page.php | 389 ++++++++++
assets/admin.css | 8 +
assets/admin.js | 29 +
changelog.txt | 63 ++
docs/FILTERS-HOOKS.md | 240 ++++++
docs/OG-TWITTER-REFERENCE.md | 183 +++++
docs/WP-CLI.md | 103 +++
includes/class-robotstxt-og-cli.php | 337 ++++++++
.../class-robotstxt-og-image-fallback.php | 247 ++++++
.../class-robotstxt-og-image-resolver.php | 583 ++++++++++++++
includes/class-robotstxt-og-meta-box.php | 219 ++++++
includes/class-robotstxt-og-rest-api.php | 209 +++++
includes/class-robotstxt-og-tags.php | 579 ++++++++++++++
languages/robotstxt-og-es_ES.mo | Bin 0 -> 10610 bytes
languages/robotstxt-og-es_ES.po | 427 ++++++++++
languages/robotstxt-og.pot | 476 ++++++++++++
readme.txt | 209 +++++
robotstxt-og.php | 45 ++
robotstxt-updater.php | 383 +++++++++
uninstall.php | 120 +++
update.json | 27 +
25 files changed, 6453 insertions(+)
create mode 100644 CHANGELOG.md
create mode 100644 LICENSE
create mode 100644 README.md
create mode 100644 admin/class-robotstxt-og-admin-settings.php
create mode 100644 admin/views/settings-page.php
create mode 100644 assets/admin.css
create mode 100644 assets/admin.js
create mode 100644 changelog.txt
create mode 100644 docs/FILTERS-HOOKS.md
create mode 100644 docs/OG-TWITTER-REFERENCE.md
create mode 100644 docs/WP-CLI.md
create mode 100644 includes/class-robotstxt-og-cli.php
create mode 100644 includes/class-robotstxt-og-image-fallback.php
create mode 100644 includes/class-robotstxt-og-image-resolver.php
create mode 100644 includes/class-robotstxt-og-meta-box.php
create mode 100644 includes/class-robotstxt-og-rest-api.php
create mode 100644 includes/class-robotstxt-og-tags.php
create mode 100644 languages/robotstxt-og-es_ES.mo
create mode 100644 languages/robotstxt-og-es_ES.po
create mode 100644 languages/robotstxt-og.pot
create mode 100644 robotstxt-og.php
create mode 100644 robotstxt-updater.php
create mode 100644 uninstall.php
create mode 100644 update.json
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..bd297af
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,38 @@
+# Changelog
+
+All notable changes to OpenGraph (by ROBOTSTXT) will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [1.0.0] - 2026-02-18
+
+### Added
+- Automatic format detection for AVIF, WebP, GIF, BMP, SVG, and TIFF featured images
+- HTTP HEAD-based resolution of compatible JPEG/PNG alternatives
+- Postmeta caching (`_og_image_fallback_url`) with automatic invalidation on featured image change
+- Negative caching via transients (1-hour TTL) to avoid repeated failed HEAD requests
+- Open Graph meta tags: `og:image`, `og:image:secure_url`, `og:image:width`, `og:image:height`, `og:image:type`
+- Direct `wp_head` tag injection (when no SEO plugin is active)
+- Yoast SEO integration via `wpseo_opengraph_image` filter
+- RankMath integration via `rank_math/opengraph/facebook/og_image` filter
+- Global fallback image setting (configurable in Settings > OpenGraph)
+- Taxonomy archive image support via `robotstxt_og_taxonomy_image` filter
+- Admin settings page (Settings > OpenGraph) with three tabs: Settings, Tools, Diagnostics
+- WP-CLI commands: `wp og-fallback resolve` and `wp og-fallback clear-cache`
+- REST API: `POST /wp-json/robotstxt-og/v1/resolve/{post_id}` and `GET /wp-json/robotstxt-og/v1/status/{post_id}`
+- Developer filters: `robotstxt_og_external_image_enabled`, `robotstxt_og_external_image_timeout`, `robotstxt_og_taxonomy_image`, `robotstxt_og_enable_logging`
+- Auto-updater via Gitea (`robotstxt-updater.php`)
+- Multisite compatible with per-site configuration
+- Full internationalization support (text domain: `robotstxt-og`)
+- `uninstall.php` with optional data deletion on plugin removal
+
+### Security
+- Nonce verification on all forms and state-changing actions
+- `manage_options` capability check on all admin pages, REST endpoints, and WP-CLI commands
+- Input sanitization via WordPress APIs throughout
+- Output escaping on all dynamic HTML
+- WordPress database APIs exclusively (no direct SQL writes; `$wpdb->prepare()` for reads)
+- CSRF protection on all state-changing actions
+
+[1.0.0]: https://git.robotstxt.es/ROBOTSTXT/robotstxt-og/releases/tag/1.0.0
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..f288702
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
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+ If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
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+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients. "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
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+
+ If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
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+receiving the covered work authorizing them to use, propagate, modify
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+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+ A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License. You may not convey a covered
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+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
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+parties who would receive the covered work from you, a discriminatory
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+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+ Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+ 12. No Surrender of Others' Freedom.
+
+ If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
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+not convey it at all. For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+ 13. Use with the GNU Affero General Public License.
+
+ Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
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+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+ 14. Revised Versions of this License.
+
+ The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time. Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+ Each version is given a distinguishing version number. If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation. If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+ If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+ Later license versions may give you additional or different
+permissions. However, no additional obligations are imposed on any
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+ 15. Disclaimer of Warranty.
+
+ THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
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+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
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+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ Copyright (C)
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..1838829
--- /dev/null
+++ b/README.md
@@ -0,0 +1,132 @@
+# OpenGraph (by ROBOTSTXT)
+
+> Intelligent Open Graph image fallback for social media crawlers.
+
+Automatically detects when a post's featured image uses a modern format (AVIF, WebP) that social media crawlers cannot render, and resolves a compatible JPEG/PNG alternative to use in `og:image` meta tags.
+
+## Requirements
+
+- **WordPress:** 6.7+
+- **PHP:** 8.2–8.5
+- **WP-CLI:** 2.x (optional, for CLI tools)
+
+## Installation
+
+```bash
+# From the plugin directory
+composer install
+```
+
+Activate the plugin through the WordPress admin or WP-CLI:
+
+```bash
+wp plugin activate robotstxt-og --allow-root
+```
+
+## Architecture
+
+```
+robotstxt-og/
+├── robotstxt-og.php # Main plugin file, constants, bootstrap
+├── includes/
+│ ├── class-robotstxt-og-image-fallback.php # Singleton, orchestration
+│ ├── class-robotstxt-og-image-resolver.php # Image detection, HEAD requests, caching
+│ ├── class-robotstxt-og-tags.php # OG tag injection, SEO plugin filters
+│ ├── class-robotstxt-og-cli.php # WP-CLI commands
+│ └── class-robotstxt-og-rest-api.php # REST API endpoints
+├── admin/
+│ ├── class-robotstxt-og-admin-settings.php # Admin page, settings, cache actions
+│ └── views/settings-page.php # Settings page template (tabbed)
+├── assets/
+│ ├── admin.js # Media uploader integration
+│ └── admin.css # Admin styles
+├── languages/
+│ └── robotstxt-og.pot # Translation template
+├── docs/
+│ ├── FILTERS-HOOKS.md # Developer filter/hook reference
+│ ├── WP-CLI.md # WP-CLI command reference
+│ └── IDEA.md # Original concept document
+├── bin/
+│ └── deploy.sh # Build and ZIP packaging script
+├── robotstxt-updater.php # Auto-updater (Gitea-based)
+├── uninstall.php # Data cleanup on uninstall
+├── readme.txt # WordPress.org plugin readme
+└── changelog.txt # Full changelog (WordPress.org format)
+```
+
+## Development
+
+### Code Standards
+
+```bash
+# Lint
+vendor/bin/phpcs .
+
+# Auto-fix
+vendor/bin/phpcbf .
+
+# PHP compatibility check (8.2–8.5)
+vendor/bin/phpcs -p . --standard=PHPCompatibility --runtime-set testVersion 8.2-8.5
+```
+
+### Regenerate translation template
+
+```bash
+wp i18n make-pot . languages/robotstxt-og.pot --domain=robotstxt-og --exclude=vendor,node_modules,tests --allow-root
+```
+
+### Build release ZIP
+
+```bash
+bash bin/deploy.sh
+```
+
+The ZIP is created at `../robotstxt-og-{version}.zip` (i.e. in `wp-content/plugins/`).
+
+## WP-CLI Commands
+
+```bash
+# Resolve fallback for a single post
+wp og-fallback resolve 123
+
+# Re-resolve all posts with featured images
+wp og-fallback resolve --all
+
+# Dry-run (no changes saved)
+wp og-fallback resolve --all --dry-run
+
+# Clear cache for a single post
+wp og-fallback clear-cache 123
+
+# Clear all caches
+wp og-fallback clear-cache --all
+```
+
+## REST API
+
+All endpoints require the `manage_options` capability.
+
+| Method | Endpoint | Description |
+|--------|----------|-------------|
+| `POST` | `/wp-json/robotstxt-og/v1/resolve/{post_id}` | Force re-resolve fallback image |
+| `GET` | `/wp-json/robotstxt-og/v1/status/{post_id}` | Get current cache status |
+
+## Filters
+
+| Filter | Default | Description |
+|--------|---------|-------------|
+| `robotstxt_og_external_image_enabled` | `true` | Enable/disable external image resolution |
+| `robotstxt_og_external_image_timeout` | `5` | HEAD request timeout (seconds) |
+| `robotstxt_og_taxonomy_image` | `''` | Image URL for taxonomy archive pages |
+| `robotstxt_og_enable_logging` | `false` | Enable debug logging to `debug.log` |
+
+Full documentation: [`docs/FILTERS-HOOKS.md`](docs/FILTERS-HOOKS.md)
+
+## License
+
+GPL-3.0-or-later — see [LICENSE](https://www.gnu.org/licenses/gpl-3.0.txt)
+
+## Author
+
+**ROBOTSTXT** — [robotstxt.es](https://www.robotstxt.es/)
+Contributors: javiercasares, robotstxt
diff --git a/admin/class-robotstxt-og-admin-settings.php b/admin/class-robotstxt-og-admin-settings.php
new file mode 100644
index 0000000..bcec130
--- /dev/null
+++ b/admin/class-robotstxt-og-admin-settings.php
@@ -0,0 +1,733 @@
+resolver = $resolver;
+ }
+
+ /**
+ * Initialize admin hooks.
+ *
+ * @since 1.0.0
+ *
+ * @return void
+ */
+ public function init(): void {
+ add_action( 'admin_menu', array( $this, 'add_settings_page' ) );
+ add_action( 'admin_init', array( $this, 'register_settings' ) );
+ add_action( 'admin_init', array( $this, 'handle_clear_cache' ) );
+ add_action( 'admin_init', array( $this, 'handle_resolve_all' ) );
+ add_action( 'admin_init', array( $this, 'handle_clear_single' ) );
+ add_action( 'admin_enqueue_scripts', array( $this, 'enqueue_admin_assets' ) );
+ }
+
+ /**
+ * Handle clear single post cache action.
+ *
+ * @since 1.0.0
+ *
+ * @return void
+ */
+ public function handle_clear_single(): void {
+ // Check if this is a single clear request.
+ $post_id_raw = filter_input( INPUT_GET, 'robotstxt_og_clear_single', FILTER_SANITIZE_NUMBER_INT );
+ if ( null === $post_id_raw ) {
+ return;
+ }
+
+ $post_id = absint( $post_id_raw );
+
+ if ( $post_id <= 0 ) {
+ return;
+ }
+
+ // Verify nonce.
+ $nonce_raw = filter_input( INPUT_GET, '_wpnonce', FILTER_SANITIZE_SPECIAL_CHARS );
+ $nonce = $nonce_raw ? sanitize_text_field( wp_unslash( $nonce_raw ) ) : '';
+
+ if ( ! wp_verify_nonce( $nonce, 'robotstxt_og_clear_single_' . $post_id ) ) {
+ wp_die( esc_html__( 'Security check failed', 'robotstxt-og' ) );
+ }
+
+ // Check permissions.
+ if ( ! current_user_can( 'manage_options' ) ) {
+ wp_die( esc_html__( 'You do not have sufficient permissions to access this page.', 'robotstxt-og' ) );
+ }
+
+ // Clear single post cache.
+ $this->resolver->clear_cache( $post_id );
+
+ // Add admin notice.
+ add_settings_error(
+ 'robotstxt_og_messages',
+ 'robotstxt_og_single_cleared',
+ /* translators: %d: post ID */
+ sprintf( __( 'Successfully cleared cached fallback URL for post #%d.', 'robotstxt-og' ), $post_id ),
+ 'success'
+ );
+
+ // Redirect back to diagnostics tab.
+ $page_url = admin_url( 'options-general.php?page=robotstxt-og-settings' );
+ wp_safe_redirect(
+ add_query_arg( 'tab', 'diagnostics', remove_query_arg( array( 'robotstxt_og_clear_single', '_wpnonce' ), $page_url ) )
+ );
+ exit;
+ }
+
+ /**
+ * Add settings page to WordPress admin menu.
+ *
+ * @since 1.0.0
+ *
+ * @return void
+ */
+ public function add_settings_page(): void {
+ add_options_page(
+ __( 'OpenGraph Settings', 'robotstxt-og' ),
+ __( 'OpenGraph', 'robotstxt-og' ),
+ 'manage_options',
+ 'robotstxt-og-settings',
+ array( $this, 'render_settings_page' )
+ );
+ }
+
+ /**
+ * Register plugin settings.
+ *
+ * @since 1.0.0
+ *
+ * @return void
+ */
+ public function register_settings(): void {
+ // Register settings.
+ register_setting(
+ 'robotstxt_og_settings',
+ 'robotstxt_og_fallback_image',
+ array(
+ 'type' => 'string',
+ 'sanitize_callback' => array( $this, 'sanitize_image_url' ),
+ 'default' => '',
+ )
+ );
+
+ register_setting(
+ 'robotstxt_og_settings',
+ 'robotstxt_og_homepage_image',
+ array(
+ 'type' => 'string',
+ 'sanitize_callback' => array( $this, 'sanitize_image_url' ),
+ 'default' => '',
+ )
+ );
+
+ register_setting(
+ 'robotstxt_og_settings',
+ 'robotstxt_og_enable_facebook',
+ array(
+ 'type' => 'boolean',
+ 'sanitize_callback' => 'rest_sanitize_boolean',
+ 'default' => true,
+ )
+ );
+
+ register_setting(
+ 'robotstxt_og_settings',
+ 'robotstxt_og_enable_twitter',
+ array(
+ 'type' => 'boolean',
+ 'sanitize_callback' => 'rest_sanitize_boolean',
+ 'default' => true,
+ )
+ );
+
+ register_setting(
+ 'robotstxt_og_settings',
+ 'robotstxt_og_twitter_card_type',
+ array(
+ 'type' => 'string',
+ 'sanitize_callback' => 'sanitize_key',
+ 'default' => 'summary_large_image',
+ )
+ );
+
+ register_setting(
+ 'robotstxt_og_settings',
+ 'robotstxt_og_twitter_site',
+ array(
+ 'type' => 'string',
+ 'sanitize_callback' => 'sanitize_text_field',
+ 'default' => '',
+ )
+ );
+
+ register_setting(
+ 'robotstxt_og_settings',
+ 'robotstxt_og_delete_data_on_uninstall',
+ array(
+ 'type' => 'boolean',
+ 'sanitize_callback' => 'rest_sanitize_boolean',
+ 'default' => false,
+ )
+ );
+
+ // --- General Settings section ---
+ add_settings_section(
+ 'robotstxt_og_main_section',
+ __( 'General Settings', 'robotstxt-og' ),
+ array( $this, 'render_main_section' ),
+ 'robotstxt-og-settings'
+ );
+
+ add_settings_field(
+ 'robotstxt_og_fallback_image',
+ __( 'Global Fallback Image', 'robotstxt-og' ),
+ array( $this, 'render_fallback_image_field' ),
+ 'robotstxt-og-settings',
+ 'robotstxt_og_main_section'
+ );
+
+ add_settings_field(
+ 'robotstxt_og_homepage_image',
+ __( 'Homepage Image', 'robotstxt-og' ),
+ array( $this, 'render_homepage_image_field' ),
+ 'robotstxt-og-settings',
+ 'robotstxt_og_main_section'
+ );
+
+ add_settings_field(
+ 'robotstxt_og_delete_data_on_uninstall',
+ __( 'Data Management', 'robotstxt-og' ),
+ array( $this, 'render_delete_data_field' ),
+ 'robotstxt-og-settings',
+ 'robotstxt_og_main_section'
+ );
+
+ // --- Social Media Tags section ---
+ add_settings_section(
+ 'robotstxt_og_social_section',
+ __( 'Social Media Tags', 'robotstxt-og' ),
+ array( $this, 'render_social_section' ),
+ 'robotstxt-og-settings'
+ );
+
+ add_settings_field(
+ 'robotstxt_og_enable_facebook',
+ __( 'Facebook / OG Tags', 'robotstxt-og' ),
+ array( $this, 'render_enable_facebook_field' ),
+ 'robotstxt-og-settings',
+ 'robotstxt_og_social_section'
+ );
+
+ add_settings_field(
+ 'robotstxt_og_enable_twitter',
+ __( 'Twitter Card Tags', 'robotstxt-og' ),
+ array( $this, 'render_enable_twitter_field' ),
+ 'robotstxt-og-settings',
+ 'robotstxt_og_social_section'
+ );
+
+ add_settings_field(
+ 'robotstxt_og_twitter_card_type',
+ __( 'Twitter Card Type', 'robotstxt-og' ),
+ array( $this, 'render_twitter_card_type_field' ),
+ 'robotstxt-og-settings',
+ 'robotstxt_og_social_section'
+ );
+
+ add_settings_field(
+ 'robotstxt_og_twitter_site',
+ __( 'Twitter/X Site Handle', 'robotstxt-og' ),
+ array( $this, 'render_twitter_site_field' ),
+ 'robotstxt-og-settings',
+ 'robotstxt_og_social_section'
+ );
+ }
+
+ /**
+ * Sanitize and validate an image URL for use as an OG image.
+ *
+ * Validates URL format and checks compatibility (JPEG/PNG). For AVIF/WebP
+ * and other incompatible formats, attempts to find a JPEG/PNG alternative.
+ * Returns empty string and adds a settings error if the URL is invalid or
+ * no compatible version can be found.
+ *
+ * @since 1.2.0
+ *
+ * @param string $raw Raw value from the settings form.
+ * @return string Validated, compatible image URL or empty string.
+ */
+ public function sanitize_image_url( string $raw ): string {
+ $url = esc_url_raw( trim( $raw ) );
+
+ if ( empty( $url ) ) {
+ return '';
+ }
+
+ if ( ! filter_var( $url, FILTER_VALIDATE_URL ) ) {
+ add_settings_error(
+ 'robotstxt_og_messages',
+ 'robotstxt_og_invalid_url',
+ __( 'The image URL is not valid. Please enter a full URL starting with https://.', 'robotstxt-og' ),
+ 'error'
+ );
+ return '';
+ }
+
+ $compatible = $this->resolver->ensure_compatible_format( $url );
+
+ if ( empty( $compatible ) ) {
+ add_settings_error(
+ 'robotstxt_og_messages',
+ 'robotstxt_og_incompatible_format',
+ __( 'The image URL is not in a compatible format (JPEG or PNG), and no compatible alternative could be found.', 'robotstxt-og' ),
+ 'error'
+ );
+ return '';
+ }
+
+ return $compatible;
+ }
+
+ /**
+ * Render main settings section description.
+ *
+ * @since 1.0.0
+ *
+ * @return void
+ */
+ public function render_main_section(): void {
+ echo '