feat: field validation, term resolution, post guard and revision points

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01At3V6SjwbMe6eMzVGW3Hs7
2026-09-25 22:29:15 +02:00
parent 98a910f056
commit 95aae74466
11 changed files with 748 additions and 0 deletions
@@ -0,0 +1,79 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\WordPress;
+
+use LIT\MCP\Abilities\Errors;
+use LIT\MCP\Integrations\WordPress\Schema\ContentSchema;
+use WP_Error;
+use WP_Post;
+
+/**
+ * Loads entries and post types for abilities, including the capability checks
+ * of spec §4.5. Every error is ready to be returned from permission()/execute().
+ * Input is not schema-validated yet when permission() runs – hence the defensive id().
+ */
+final class PostGuard
+{
+    public static function editable(mixed $postId, ContentSchema $schema, string $field = 'post_id'): WP_Post|WP_Error
+    {
+        $id = self::id($postId);
+        if ($id === null) {
+            return Errors::invalidInput(
+                sprintf('%s fehlt oder ist ungültig.', $field),
+                [$field => 'positive Ganzzahl erwartet']
+            );
+        }
+
+        $post = get_post($id);
+        if (! $post instanceof WP_Post || ! $schema->isManaged((string) $post->post_type)) {
+            return Errors::notFound(sprintf('Eintrag %d nicht gefunden (oder kein unterstützter Inhaltstyp).', $id));
+        }
+
+        if (! current_user_can('edit_post', $id)) {
+            return Errors::forbidden(sprintf('Keine Berechtigung, Eintrag %d zu bearbeiten.', $id));
+        }
+
+        return $post;
+    }
+
+    /**
+     * The brief declares this `: object|WP_Error`, but `object` already covers every
+     * class type, so PHP refuses `object` inside a union ("Type object cannot be
+     * part of a union type" – fatal at compile time). WP_Error is itself an object,
+     * so a plain `object` return type is accurate and still lets callers branch with
+     * `is_wp_error()` / `instanceof WP_Error`, exactly like editable() above.
+     */
+    public static function postType(mixed $postType, ContentSchema $schema, string $cap): object
+    {
+        $name = is_string($postType) ? $postType : '';
+        $object = $name !== '' && $schema->isManaged($name) ? get_post_type_object($name) : null;
+        if (! is_object($object)) {
+            return Errors::notFound(
+                sprintf('Inhaltstyp "%s" ist nicht verfügbar.', $name),
+                'Verfügbare Inhaltstypen über lit-content-types abrufen.'
+            );
+        }
+
+        $capability = isset($object->cap->{$cap}) ? (string) $object->cap->{$cap} : $cap;
+        if (! current_user_can($capability)) {
+            return Errors::forbidden(sprintf('Keine Berechtigung für Inhaltstyp "%s".', $name));
+        }
+
+        return $object;
+    }
+
+    public static function id(mixed $value): ?int
+    {
+        if (is_int($value)) {
+            return $value > 0 ? $value : null;
+        }
+
+        if (is_string($value) && ctype_digit($value) && (int) $value > 0) {
+            return (int) $value;
+        }
+
+        return null;
+    }
+}