AsterionWP2026/tools/av-bricks-rest-bridge.php

<?php
/**
 * Plugin Name: Asterion — Bricks REST Bridge
 * Description: Exposes Bricks Builder data (templates CPT + page/post/CPT meta keys) over the WP REST API so the bricks-mcp-server (sabiertas) can read/write Bricks content. Idempotent — safe to keep installed.
 *
 * Why this is needed :
 *  - Bricks registers the bricks_template CPT WITHOUT show_in_rest, so /wp/v2/bricks_template returns 404.
 *  - The Bricks element JSON lives in post_meta keys (_bricks_page_content_2 etc.) that aren't exposed by default.
 *  - register_post_meta() with show_in_rest=true is the canonical way to expose them; meta is then read/written via /wp/v2/<post_type>/<id> with the `meta` field.
 *
 * Auth :
 *  - Read : public (REST default for show_in_rest)
 *  - Write : edit_posts capability (=> the WP Application Password user must have at least Editor role)
 */

defined('ABSPATH') || exit;

/* ----------------------------------------------------------------
   1) Force show_in_rest=true on bricks_template + our CPTs.
   ---------------------------------------------------------------- */
add_filter('register_post_type_args', function ($args, $post_type) {

    // bricks_template intentionally excluded : touching its supports/show_in_rest
    // breaks Bricks's own builder (it expects the original registration verbatim).
    // The MCP server doesn't need REST access to templates anyway — we use direct
    // PHP scripts to manage them. Only case_study + scenario stay REST-exposed.
    $needs_rest = ['case_study', 'scenario'];

    if (! in_array($post_type, $needs_rest, true)) {
        return $args;
    }

    $args['show_in_rest']          = true;
    $args['rest_base']             = $post_type . 's';
    $args['rest_controller_class'] = 'WP_REST_Posts_Controller';

    // Only add 'custom-fields' so the meta field is exposed via REST.
    $existing_supports = $args['supports'] ?? [];
    if (! in_array('custom-fields', $existing_supports, true)) {
        $existing_supports[] = 'custom-fields';
    }
    $args['supports'] = $existing_supports;

    return $args;
}, 10, 2);

/* ----------------------------------------------------------------
   2) Register Bricks meta keys for REST on every relevant post type.
   ---------------------------------------------------------------- */
add_action('init', function () {

    // Post types that may carry Bricks content
    $post_types = ['page', 'post', 'bricks_template', 'case_study', 'scenario'];

    // Bricks meta keys we want exposed (read+write) over REST
    // Keys come from wp-content/themes/bricks/functions.php
    $bricks_meta = [
        '_bricks_page_content_2'    => 'string', // The element JSON (the main payload)
        '_bricks_page_css_2'        => 'string',
        '_bricks_page_header_2'     => 'string',
        '_bricks_page_footer_2'     => 'string',
        '_bricks_page_settings'     => 'string',
        '_bricks_template_type'     => 'string',
        '_bricks_template_settings' => 'string',
    ];

    $auth_cb = function () {
        return current_user_can('edit_posts');
    };

    // Pass-through sanitize : keep the JSON string verbatim. Default sanitize for
    // type=string strips slashes / escapes which corrupts our JSON payload.
    $sanitize_passthrough = function ($value) { return $value; };

    foreach ($post_types as $type) {
        foreach ($bricks_meta as $meta_key => $meta_type) {
            register_post_meta($type, $meta_key, [
                'type'              => $meta_type,
                'single'            => true,
                'show_in_rest'      => true,
                'auth_callback'     => $auth_cb,
                'sanitize_callback' => $sanitize_passthrough,
            ]);
        }
    }
}, 30); // priority 30 — after both Bricks (10-25) and our CPTs registration (10)

/* ----------------------------------------------------------------
   3) Permit also unknown _bricks_* meta keys (e.g. _bricks_snapshot_<ts>)
      so MCP snapshots work without us pre-registering each key.
   ---------------------------------------------------------------- */
add_filter('is_protected_meta', function ($protected, $meta_key, $meta_type) {
    if ($meta_type !== 'post') return $protected;
    if (strpos($meta_key, '_bricks_snapshot_') === 0) {
        return false; // expose snapshot meta in REST despite the leading underscore
    }
    return $protected;
}, 10, 3);

/* ----------------------------------------------------------------
   4) AUTO-MIRROR : the bricks-mcp-server writes element JSON to
      _bricks_page_content_2, but Bricks reads HEADER templates from
      _bricks_page_header_2 and FOOTER templates from _bricks_page_footer_2.
      Mirror the content into the correct key whenever a bricks_template
      with type=header/footer is saved.
   ---------------------------------------------------------------- */
/* DUAL-FORMAT META READ : the MCP server writes Bricks element data as a JSON
   string into post_meta. Bricks's renderer expects a PHP array. We keep the JSON
   string format in DB (so REST reads it back fine for the MCP's Json.parse), and
   decode on the fly when Bricks reads via get_post_meta (non-REST context).
   Result : same value, two views — JSON for the MCP, array for the renderer. */
add_filter('get_post_metadata', 'av_decode_bricks_meta_for_renderer', 10, 5);

function av_decode_bricks_meta_for_renderer($value, $post_id, $meta_key, $single, $meta_type) {
    // Only post-type meta concerns us
    if ($meta_type !== 'post') return $value;

    // Only Bricks element content keys
    $content_keys = ['_bricks_page_content_2', '_bricks_page_header_2', '_bricks_page_footer_2'];
    if (! in_array($meta_key, $content_keys, true)) return $value;

    // In REST context, leave the raw string for the MCP server
    if (defined('REST_REQUEST') && REST_REQUEST) return $value;

    // Bricks renderer context : fetch the raw stored value (bypassing this filter
    // via remove_filter, then re-add) and decode JSON → array
    remove_filter('get_post_metadata', __FUNCTION__, 10);
    $raw = get_post_meta($post_id, $meta_key, $single);
    add_filter('get_post_metadata', __FUNCTION__, 10, 5);

    if (! is_string($raw)) return $value;
    $trim = trim($raw);
    if ($trim === '' || $trim === '[]') return $value;
    if ($trim[0] !== '[' && $trim[0] !== '{') return $value;

    $decoded = json_decode($raw, true);
    if (! is_array($decoded)) return $value;

    // WP's get_metadata_raw() convention for filter return values :
    //   - When filter returns array AND $single=true  → WP returns $check[0]
    //   - When filter returns array AND $single=false → WP returns $check as-is
    // Both cases need a list wrapper around our decoded value so WP's
    // single-mode auto-indexing yields the decoded array (not the section).
    return [$decoded];
}

add_action('updated_post_meta', 'av_mirror_bricks_template_content', 10, 4);
add_action('added_post_meta',   'av_mirror_bricks_template_content', 10, 4);

function av_mirror_bricks_template_content($meta_id, $post_id, $meta_key, $meta_value) {
    // Trigger 1 : content updated → mirror to header/footer if type already known
    // Trigger 2 : type updated → re-mirror existing content (fixes the order-of-writes
    //             on REST create_template which writes content before type)
    if (! in_array($meta_key, ['_bricks_page_content_2', '_bricks_template_type'], true)) return;
    if (get_post_type($post_id) !== 'bricks_template') return;

    // Reuse the av_decode filter logic by reading via get_post_meta (which now
    // returns array) when the value is JSON, or by direct decoding here.
    if ($meta_key === '_bricks_page_content_2') {
        $type    = get_post_meta($post_id, '_bricks_template_type', true);
        $content = is_string($meta_value) ? $meta_value : '';
    } else {
        // type just updated → fetch raw content (bypass our filter to get string)
        $type = is_string($meta_value) ? $meta_value : '';
        remove_filter('get_post_metadata', 'av_decode_bricks_meta_for_renderer', 10);
        $content = get_post_meta($post_id, '_bricks_page_content_2', true);
        add_filter('get_post_metadata', 'av_decode_bricks_meta_for_renderer', 10, 5);
    }

    $mirror_key = match ($type) {
        'header' => '_bricks_page_header_2',
        'footer' => '_bricks_page_footer_2',
        default  => null,
    };

    if (! $mirror_key) return;

    // Bricks stores element JSON as a PHP-serialized array. Decode JSON string to array first.
    $value = is_string($content) ? json_decode($content, true) : $content;
    if (! is_array($value)) return;

    // Bypass register_post_meta string-coercion by writing a serialized blob directly via $wpdb.
    // This is what Bricks's own builder save does — the value lands as a serialized PHP array,
    // which `get_post_meta($id, $key, true)` auto-unserializes back to array on read.
    global $wpdb;
    $serialized = maybe_serialize($value);
    $existing   = $wpdb->get_var($wpdb->prepare(
        "SELECT meta_id FROM {$wpdb->postmeta} WHERE post_id=%d AND meta_key=%s LIMIT 1",
        $post_id, $mirror_key
    ));

    if ($existing) {
        $wpdb->update(
            $wpdb->postmeta,
            ['meta_value' => $serialized],
            ['meta_id'    => $existing],
            ['%s'], ['%d']
        );
    } else {
        $wpdb->insert(
            $wpdb->postmeta,
            ['post_id' => $post_id, 'meta_key' => $mirror_key, 'meta_value' => $serialized],
            ['%d', '%s', '%s']
        );
    }
    wp_cache_delete($post_id, 'post_meta');
}

/* ----------------------------------------------------------------
   5) BACKFILL : trigger a manual mirror via URL.
      Useful one-shot for templates created before this plugin was installed.
      Visit /?av_mirror_template=ID
   ---------------------------------------------------------------- */
/* One-shot : ensure all Bricks content meta is stored as JSON STRING in DB.
   - PHP-serialized arrays (legacy from earlier hook) → re-encode to JSON
   - JSON strings → leave alone
   This is the canonical storage format. The av_decode filter handles
   the array-view for Bricks's renderer at read time.
   /?av_fix_all_bricks_content=1 */
add_action('init', function () {
    if (empty($_GET['av_fix_all_bricks_content'])) return;
    if (! in_array($_SERVER['SERVER_NAME'] ?? '', ['localhost', '127.0.0.1'], true)) wp_die('localhost only');

    global $wpdb;
    $rows = $wpdb->get_results(
        "SELECT meta_id, post_id, meta_key, meta_value
         FROM {$wpdb->postmeta}
         WHERE meta_key IN ('_bricks_page_content_2','_bricks_page_header_2','_bricks_page_footer_2')
           AND LENGTH(meta_value) > 4"
    );

    $report = ['Normalizing Bricks content meta to JSON strings...'];
    foreach ($rows as $r) {
        $val   = $r->meta_value;
        $first = $val[0] ?? '';

        if ($first === '[' || $first === '{') {
            // Already JSON string : skip
            $report[] = "  OK   meta_id={$r->meta_id} post={$r->post_id} key={$r->meta_key} (JSON)";
            continue;
        }

        // Serialized PHP array → unserialize, JSON-encode
        if (is_serialized($val)) {
            $array = unserialize($val);
            if (is_array($array)) {
                $json = wp_json_encode($array);
                $wpdb->update(
                    $wpdb->postmeta,
                    ['meta_value' => $json],
                    ['meta_id'    => $r->meta_id],
                    ['%s'], ['%d']
                );
                wp_cache_delete($r->post_id, 'post_meta');
                $report[] = "  CONV meta_id={$r->meta_id} post={$r->post_id} key={$r->meta_key} (" . count($array) . " elements, " . strlen($json) . " bytes)";
                continue;
            }
        }

        $report[] = "  SKIP meta_id={$r->meta_id} post={$r->post_id} key={$r->meta_key} (unknown format)";
    }

    header('Content-Type: text/plain; charset=utf-8');
    echo implode("\n", $report);
    exit;
});

add_action('init', function () {
    if (empty($_GET['av_mirror_template'])) return;
    // localhost-only debug — no auth required (we're on http://localhost:10004)
    if (! in_array($_SERVER['SERVER_NAME'] ?? '', ['localhost', '127.0.0.1'], true)) wp_die('localhost only');

    $id      = (int) $_GET['av_mirror_template'];
    $content = get_post_meta($id, '_bricks_page_content_2', true);
    $type    = get_post_meta($id, '_bricks_template_type', true);

    if (! is_string($content) && ! is_array($content)) wp_die('no content meta');

    $value = is_string($content) ? json_decode($content, true) : $content;
    if (! is_array($value)) wp_die('content is not an array');

    $mirror_key = match ($type) {
        'header' => '_bricks_page_header_2',
        'footer' => '_bricks_page_footer_2',
        default  => null,
    };

    if (! $mirror_key) wp_die("no mirror needed for type=$type");

    // Write directly to DB as a serialized PHP array (the format Bricks's renderer expects)
    global $wpdb;
    $serialized = maybe_serialize($value);
    $existing = $wpdb->get_var($wpdb->prepare(
        "SELECT meta_id FROM {$wpdb->postmeta} WHERE post_id=%d AND meta_key=%s LIMIT 1",
        $id, $mirror_key
    ));
    if ($existing) {
        $wpdb->update($wpdb->postmeta, ['meta_value' => $serialized], ['meta_id' => $existing], ['%s'], ['%d']);
    } else {
        $wpdb->insert($wpdb->postmeta, ['post_id' => $id, 'meta_key' => $mirror_key, 'meta_value' => $serialized], ['%d', '%s', '%s']);
    }
    wp_cache_delete($id, 'post_meta');

    // Verify
    $after = get_post_meta($id, $mirror_key, true);
    $is_array = is_array($after);

    wp_die('<pre style="font:12px/1.5 monospace;padding:2rem;background:#0B1F3A;color:#E0C892;">'
        . esc_html("Mirror done : template #$id ($type)\n  _bricks_page_content_2 -> $mirror_key\n  " . count($value) . " elements\n  stored as " . ($is_array ? 'array (correct)' : 'string (WRONG)'))
        . '</pre>', 'Mirror done');
});