<?php
/**
 * Hatch Blocks - supported-blocks whitelist gate.
 *
 * When the option `hatch_blocks_disable_unsupported` is truthy, the Gutenberg
 * inserter is narrowed to the exact list of core blocks Hatch styles
 * end-to-end. "Styled end-to-end" here means the block has explicit
 * `.wp-block-<slug>` CSS in the shared base layer
 * (astro-starter/src/styles/core-blocks.css) that every Hatch theme inherits,
 * and the per-theme files override on top of that base via element selectors
 * + `.hatch-theme-<name>` token scopes.
 *
 * The whitelist was produced by an audit of
 * astro-starter/src/styles/{core-blocks,theme-blog,theme-tech,theme-docs}.css
 * on 2026-08-13 (see .claude/scratch/block-coverage.md for the full table).
 *
 * Existing content stays intact: this filter only affects what the editor
 * inserter shows for NEW insertions. Posts that already reference an
 * unsupported block (e.g. legacy `core/query`) render unchanged.
 *
 * Default: OFF. Ships as an opt-in toggle on the Plugin Bridge tab.
 *
 * @package Hatch
 * @since 0.7.5
 */

defined( 'ABSPATH' ) || exit;

if ( ! class_exists( 'Hatch_Blocks' ) ) :

	class Hatch_Blocks {

		/**
		 * Option key. Truthy = narrow inserter to the whitelist.
		 */
		const OPTION_KEY = 'hatch_blocks_disable_unsupported';

		/**
		 * The 36 core blocks that carry `.wp-block-<slug>` CSS in
		 * astro-starter/src/styles/core-blocks.css. Audit stamp 2026-08-13.
		 *
		 * Excluded (10) for the record: list-item, query, post-terms,
		 * query-title, query-pagination, query-pagination-next,
		 * query-pagination-previous, query-pagination-numbers, query-no-results,
		 * html. See .claude/scratch/block-coverage.md.
		 *
		 * @return string[]
		 */
		public static function whitelist(): array {
			return array(
				// Text (7).
				'core/paragraph',
				'core/heading',
				'core/list',
				'core/quote',
				'core/pullquote',
				'core/code',
				'core/preformatted',
				'core/verse',
				// Media (6).
				'core/image',
				'core/gallery',
				'core/video',
				'core/audio',
				'core/cover',
				'core/embed',
				// Structure (7).
				'core/columns',
				'core/column',
				'core/group',
				'core/separator',
				'core/spacer',
				'core/table',
				'core/details',
				// Interactive (2).
				'core/button',
				'core/buttons',
				// Utility (1).
				'core/file',
				// Query loop scaffolding + post blocks that DO have base CSS (8).
				// core/query itself and pagination scaffolds are EXCLUDED so we
				// document that gap in the docs; users needing query loops leave
				// the toggle OFF.
				'core/post-template',
				'core/post-title',
				'core/post-excerpt',
				'core/post-date',
				'core/post-featured-image',
				'core/post-author',
				'core/post-content',
				// Widget-family blocks with base CSS (5).
				'core/latest-posts',
				'core/categories',
				'core/tag-cloud',
				'core/rss',
				'core/search',
			);
		}

		/**
		 * Register hooks.
		 */
		public static function init(): void {
			if ( ! self::is_enabled() ) {
				return;
			}
			// Priority 20 runs after any earlier plugin that seeded a base list,
			// so we can safely intersect and not accidentally re-enable blocks
			// another admin explicitly hid.
			add_filter( 'allowed_block_types_all', array( __CLASS__, 'maybe_disable_unsupported' ), 20, 2 );
		}

		/**
		 * Is the master toggle ON?
		 *
		 * Multisite note: this deliberately uses get_option() (per-site) and NOT
		 * get_site_option() (network-wide). Each site in a multisite install
		 * decides its own block whitelist because block support is a
		 * per-site editorial concern: a docs sub-site may want the full palette
		 * while a landing-page sub-site wants the narrow list. Do not "fix" this
		 * to network-wide storage without an explicit product decision.
		 */
		public static function is_enabled(): bool {
			return (bool) get_option( self::OPTION_KEY, 0 );
		}

		/**
		 * Return the whitelist size for UI display.
		 */
		public static function count(): int {
			return count( self::whitelist() );
		}

		/**
		 * Filter callback for `allowed_block_types_all`. Narrows the inserter to
		 * the whitelist only for post types that are public and use the block
		 * editor. Widget/site-editor contexts are left alone since restricting
		 * them would break FSE navigation blocks Hatch does not (yet) style.
		 *
		 * @param bool|string[]           $allowed Existing allowlist or true for all.
		 * @param WP_Block_Editor_Context $context Editor context.
		 * @return bool|string[]
		 */
		public static function maybe_disable_unsupported( $allowed, $context = null ) {
			// Only apply in post-editor context. Widget editor and site editor
			// need the full palette or they break; the toggle is scoped to
			// "content authors picking blocks for posts and pages".
			if ( $context && isset( $context->post ) && $context->post ) {
				$post_type = get_post_type( $context->post );
				if ( $post_type ) {
					$type_obj = get_post_type_object( $post_type );
					if ( ! $type_obj || ! $type_obj->public ) {
						return $allowed;
					}
				}
			} elseif ( $context && ! empty( $context->name ) && 'core/edit-post' !== $context->name ) {
				// Any non-post editor context (e.g. widgets, navigation): skip.
				return $allowed;
			}

			// Another filter already turned every block off: keep it that way.
			if ( false === $allowed ) {
				return false;
			}

			$whitelist = self::whitelist();

			// Respect a narrower list a prior filter already set: intersect.
			if ( is_array( $allowed ) ) {
				return array_values( array_intersect( $allowed, $whitelist ) );
			}

			return $whitelist;
		}
	}

	Hatch_Blocks::init();

endif;