<?php
/**
 * @package AgentgateWebMCP
 */

namespace AgentgateWebMCP;

defined( 'ABSPATH' ) || exit;

class Tools_Registry {

	private const CAT = 'webmcp';

	public function setup_category(): void {
		wp_register_ability_category( self::CAT, [
			'label'       => __( 'WebMCP', 'agentgate-for-webmcp' ),
			'description' => __( 'Tools available to AI agents through the WebMCP browser API.', 'agentgate-for-webmcp' ),
		] );
	}

	public function setup_tools(): void {
		if ( ! apply_filters( 'webmcp_register_default_tools', true ) ) {
			return;
		}

		$this->register_search();
		$this->register_post();
		$this->register_categories();
	}

	// --- wp/search-posts --------------------------------------------------

	private function register_search(): void {
		wp_register_ability( 'wp/search-posts', [
			'label'       => __( 'Search Posts', 'agentgate-for-webmcp' ),
			'description' => __( 'Find published posts matching a keyword. Returns title, excerpt, and link for each result.', 'agentgate-for-webmcp' ),
			'category'    => self::CAT,
			'input_schema' => [
				'type'       => 'object',
				'required'   => [ 'query' ],
				'properties' => [
					'query' => [ 'type' => 'string', 'description' => __( 'Search term.', 'agentgate-for-webmcp' ) ],
					'limit' => [ 'type' => 'integer', 'description' => __( 'Max results (1-50).', 'agentgate-for-webmcp' ), 'default' => 10, 'minimum' => 1, 'maximum' => 50 ],
				],
			],
			'execute_callback'    => [ $this, 'handle_search' ],
			'permission_callback' => '__return_true',
			'meta'                => [ 'webmcp_readonly' => true, 'webmcp_public' => true ],
		] );
	}

	public function handle_search( array $p ) {
		$q = sanitize_text_field( $p['query'] ?? '' );
		if ( $q === '' ) {
			return new \WP_Error( 'missing_query', __( 'A search query is required.', 'agentgate-for-webmcp' ) );
		}

		$n = isset( $p['limit'] ) ? max( 1, min( 50, intval( $p['limit'] ) ) ) : 10;

		return array_map(
			[ $this, 'format_post_summary' ],
			get_posts( [ 'post_status' => 'publish', 'posts_per_page' => $n, 's' => $q ] )
		);
	}

	// --- wp/get-post ------------------------------------------------------

	private function register_post(): void {
		wp_register_ability( 'wp/get-post', [
			'label'       => __( 'Get Post', 'agentgate-for-webmcp' ),
			'description' => __( 'Retrieve a single published post by ID or slug. Returns full content, categories, and tags.', 'agentgate-for-webmcp' ),
			'category'    => self::CAT,
			'input_schema' => [
				'type'       => 'object',
				'properties' => [
					'id'   => [ 'type' => 'integer', 'description' => __( 'Post ID.', 'agentgate-for-webmcp' ) ],
					'slug' => [ 'type' => 'string',  'description' => __( 'Post URL slug.', 'agentgate-for-webmcp' ) ],
				],
			],
			'execute_callback'    => [ $this, 'handle_post' ],
			'permission_callback' => '__return_true',
			'meta'                => [ 'webmcp_readonly' => true, 'webmcp_public' => true ],
		] );
	}

	public function handle_post( array $p ) {
		$post = $this->find_post( $p );

		if ( ! $post ) {
			return new \WP_Error( 'not_found', __( 'Post not found.', 'agentgate-for-webmcp' ), [ 'status' => 404 ] );
		}

		$cats = wp_get_post_categories( $post->ID, [ 'fields' => 'names' ] );
		$tags = wp_get_post_tags( $post->ID, [ 'fields' => 'names' ] );

		return [
			'id'         => $post->ID,
			'title'      => get_the_title( $post ),
			'content'    => wp_strip_all_tags( apply_filters( 'the_content', $post->post_content ) ), // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound -- Core WordPress filter.
			'excerpt'    => wp_strip_all_tags( get_the_excerpt( $post ) ),
			'published'  => get_the_date( 'c', $post ),
			'link'       => get_permalink( $post ),
			'categories' => is_array( $cats ) ? array_values( $cats ) : [],
			'tags'       => is_array( $tags ) ? array_values( $tags ) : [],
		];
	}

	private function find_post( array $p ): ?\WP_Post {
		if ( ! empty( $p['id'] ) ) {
			$post = get_post( intval( $p['id'] ) );
		} elseif ( ! empty( $p['slug'] ) ) {
			$hits = get_posts( [ 'name' => sanitize_title( $p['slug'] ), 'post_status' => 'publish', 'numberposts' => 1 ] );
			$post = $hits[0] ?? null;
		} else {
			return null;
		}

		if ( ! $post instanceof \WP_Post ) {
			return null;
		}

		if ( $post->post_status !== 'publish' && ! current_user_can( 'read_post', $post->ID ) ) {
			return null;
		}

		return $post;
	}

	// --- wp/get-categories ------------------------------------------------

	private function register_categories(): void {
		wp_register_ability( 'wp/get-categories', [
			'label'       => __( 'Get Categories', 'agentgate-for-webmcp' ),
			'description' => __( 'List all post categories including name, description, and post count.', 'agentgate-for-webmcp' ),
			'category'    => self::CAT,
			'input_schema' => [ 'type' => 'object', 'properties' => new \stdClass() ],
			'execute_callback'    => [ $this, 'handle_categories' ],
			'permission_callback' => '__return_true',
			'meta'                => [ 'webmcp_readonly' => true, 'webmcp_public' => true ],
		] );
	}

	public function handle_categories( array $p ): array {
		$cats = get_categories( [ 'hide_empty' => false, 'orderby' => 'name' ] );

		if ( ! is_array( $cats ) ) {
			return [];
		}

		return array_map( fn( \WP_Term $c ) => [
			'id'          => $c->term_id,
			'name'        => $c->name,
			'slug'        => $c->slug,
			'description' => wp_strip_all_tags( $c->description ),
			'post_count'  => (int) $c->count,
			'link'        => get_category_link( $c->term_id ),
		], array_values( $cats ) );
	}

	// --- shared helpers ---------------------------------------------------

	private function format_post_summary( \WP_Post $p ): array {
		return [
			'id'        => $p->ID,
			'title'     => get_the_title( $p ),
			'snippet'   => wp_strip_all_tags( get_the_excerpt( $p ) ),
			'link'      => get_permalink( $p ),
			'published' => get_the_date( 'c', $p ),
		];
	}
}