<?php
/**
 * Tools that make the AI faster and cheaper: batch calls, tool discovery,
 * history/undo, and the search/fetch pair ChatGPT connectors expect.
 *
 * @package HandyMCP
 */

namespace HandyMCP\Integrations;

use HandyMCP\Plugin;
use HandyMCP\Tools\History;
use HandyMCP\Tools\Registry;
use HandyMCP\Tools\Util;

defined( 'ABSPATH' ) || exit;

/**
 * Assistant tools.
 */
final class Assistant {

	/**
	 * Register.
	 *
	 * @param Registry $r Registry.
	 */
	public static function register( Registry $r ): void {
		$r->group(
			'assistant',
			array(
				'label'       => 'AI helpers and undo',
				'description' => 'Batch actions, on-demand tool lookup, undo history, and site search for AI apps.',
				'detected'    => true,
				'plugins'     => array( 'Built in' => '' ),
			)
		);

		$r->add(
			array(
				'name'        => 'batch',
				'group'       => 'assistant',
				'title'       => 'Run several tools in one call',
				'description' => 'Run up to 30 tool calls in order in a single request, e.g. create all pages of a site, upload images and build the menu at once. Each item is {"tool":"name","args":{...}}. Use "$N.field" in a string arg to insert a value from the result of item N (0-based), e.g. "$0.id". Stops at the first error unless continue_on_error.',
				'write'       => true,
				'cap'         => 'read',
				'scope'       => 'read',
				'input'       => array(
					'required'   => array( 'calls' ),
					'properties' => array(
						'calls'             => array(
							'type'     => 'array',
							'minItems' => 1,
							'maxItems' => 30,
							'items'    => array(
								'type'                 => 'object',
								'required'             => array( 'tool' ),
								'properties'           => array(
									'tool' => array( 'type' => 'string' ),
									'args' => array( 'type' => 'object', 'additionalProperties' => true ),
								),
								'additionalProperties' => false,
							),
						),
						'continue_on_error' => array( 'type' => 'boolean', 'default' => false ),
					),
				),
				'run'         => static function ( array $a, $identity ) {
					$reg     = Plugin::instance()->container()->get( 'registry' );
					$results = array();
					$ok      = 0;
					History::end(); // Every inner call records its own undo entry.
					foreach ( $a['calls'] as $i => $call ) {
						if ( 'batch' === $call['tool'] ) {
							$results[] = array( 'tool' => 'batch', 'error' => array( 'code' => 'nested_batch', 'message' => 'Batches cannot be nested.' ) );
							continue;
						}
						$args = self::substitute( (array) ( $call['args'] ?? array() ), $results );
						if ( ! $reg->has( $call['tool'], $identity ) ) {
							$res = array( 'result' => array( 'error' => array( 'code' => 'unknown_tool', 'message' => 'Unknown or disabled tool: ' . $call['tool'] . \HandyMCP\Tools\Registry::pro_hint( (string) $call['tool'] ) ) ), 'error' => true );
						} else {
							$res = $reg->call( $call['tool'], $args, $identity );
						}
						$results[] = array_merge( array( 'tool' => $call['tool'] ), is_array( $res['result'] ) ? $res['result'] : array( 'result' => $res['result'] ) );
						if ( $res['error'] ) {
							if ( ! $a['continue_on_error'] ) {
								break;
							}
						} else {
							++$ok;
						}
					}
					return array( 'completed' => $ok, 'total' => count( $a['calls'] ), 'results' => $results );
				},
			)
		);

		$r->add(
			array(
				'name'        => 'tools_find',
				'group'       => 'assistant',
				'title'       => 'Find tools',
				'description' => 'Search all tools available on this site by keyword (e.g. "elementor template", "menu", "seo") and get their input schemas. Then call them directly or with tools_run.',
				'input'       => array( 'required' => array( 'query' ), 'properties' => array( 'query' => array( 'type' => 'string' ) ) ),
				'run'         => static function ( array $a, $identity ) {
					$words = array_filter( preg_split( '/\s+/', strtolower( $a['query'] ) ) );
					$found = array();
					foreach ( Plugin::instance()->container()->get( 'registry' )->definitions( $identity, true ) as $t ) {
						if ( in_array( $t['name'], array( 'tools_find', 'tools_run', 'batch' ), true ) ) {
							continue;
						}
						$hay   = strtolower( $t['name'] . ' ' . $t['title'] . ' ' . $t['description'] );
						$score = 0;
						$hits  = 0;
						$named = 0;
						foreach ( $words as $w ) {
							$in     = substr_count( $hay, $w );
							$nm     = false !== strpos( $t['name'], $w );
							$hits  += $in ? 1 : 0;
							$named += $nm ? 1 : 0;
							$score += min( $in, 3 ) + ( $nm ? 4 : 0 );
						}
						if ( $score && $hits * 2 >= count( $words ) ) {
							$found[] = array( 'score' => $score, 'named' => $named, 'tool' => array( 'name' => $t['name'], 'description' => '' !== $t['description'] ? $t['description'] : $t['title'], 'inputSchema' => $t['inputSchema'] ) + ( empty( $t['annotations']['destructiveHint'] ) ? array() : array( 'destructive' => true ) ) );
						}
					}
					usort( $found, static function ( $x, $y ) { return $y['score'] <=> $x['score']; } );
					$min   = $found ? $found[0]['score'] * 0.4 : 0;
					$named = $found && $found[0]['named'] * 2 > count( $words );
					$top   = array_filter( $found, static function ( $f ) use ( $min ) { return $f['score'] >= $min; } );
					$out   = array( 'tools' => array_column( array_slice( $top, 0, $named ? 6 : 3 ), 'tool' ) );
					if ( ! $named ) {
						$out['note'] = 'No tool matches. HandyMCP Pro adds tools for WooCommerce, other page builders, plugins and themes, files and more (https://handymcp.com/#pricing).';
					}
					return $out;
				},
			)
		);

		$r->add(
			array(
				'name'        => 'tools_run',
				'group'       => 'assistant',
				'title'       => 'Run a tool by name',
				'description' => 'Run any tool found with tools_find: {"name":"...","arguments":{...}}.',
				'write'       => true,
				'scope'       => 'read',
				'input'       => array(
					// Inner tool arguments sent next to "name" are moved into "arguments" below.
					'additionalProperties' => true,
					'required'   => array( 'name' ),
					'properties' => array(
						'name'      => array( 'type' => 'string' ),
						'arguments' => array( 'type' => 'object', 'additionalProperties' => true ),
					),
				),
				'run'         => static function ( array $a, $identity ) {
					$reg = Plugin::instance()->container()->get( 'registry' );
					if ( in_array( $a['name'], array( 'tools_run', 'batch' ), true ) || ! $reg->has( $a['name'], $identity ) ) {
						return new \WP_Error( 'unknown_tool', 'Unknown or disabled tool: ' . $a['name'] . \HandyMCP\Tools\Registry::pro_hint( (string) $a['name'] ) );
					}
					// Arguments sent next to "name" instead of inside "arguments": merge them, explicit arguments win.
					$args  = is_array( $a['arguments'] ?? null ) ? $a['arguments'] : array();
					$extra = array_diff_key( $a, array( 'name' => 1, 'arguments' => 1 ) );
					$args  = array_merge( $extra, $args );
					History::end();
					$res = $reg->call( $a['name'], $args, $identity );
					\HandyMCP\Tools\Registry::$inner_logged = true;
					if ( $res['error'] ) {
						$e = $res['result']['error'];
						return new \WP_Error( $e['code'], $e['message'], $e['details'] ?? null );
					}
					return is_array( $res['result'] ) ? $res['result'] : array( 'result' => $res['result'] );
				},
			)
		);

		$r->add(
			array(
				'name'        => 'activity_list',
				'group'       => 'assistant',
				'title'       => 'Read the activity log',
				'description' => 'Recent requests from AI apps, newest first, as shown in HandyMCP > Activity. Default: errors from the last 7 days. Use it to find out why a change failed or what an app did. Administrators only.',
				'cap'         => 'manage_options',
				'input'       => array(
					'properties' => array(
						'status' => array( 'type' => 'string', 'enum' => array( 'error', 'denied', 'ok', 'any' ), 'default' => 'error' ),
						'hours'  => array( 'type' => 'integer', 'minimum' => 1, 'maximum' => 720, 'default' => 168, 'description' => 'How far back to look.' ),
						'tool'   => array( 'type' => 'string', 'maxLength' => 120, 'pattern' => '^[a-z0-9_]*$' ),
						'limit'  => array( 'type' => 'integer', 'minimum' => 1, 'maximum' => 100, 'default' => 30 ),
					),
				),
				'run'         => static function ( array $a ) {
					global $wpdb;
					$status = (string) ( $a['status'] ?? 'error' );
					$since  = gmdate( 'Y-m-d H:i:s', time() - (int) ( $a['hours'] ?? 168 ) * HOUR_IN_SECONDS );
					$tool   = (string) ( $a['tool'] ?? '' );
					$limit  = (int) ( $a['limit'] ?? 30 );
					$table  = \HandyMCP\Database\Installer::table( 'log' );
					// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- custom table, must be current.
					$rows = $wpdb->get_results( $wpdb->prepare( 'SELECT created_at, client, tool, status, object_ref, summary, duration_ms FROM %i WHERE created_at >= %s AND ( %s = %s OR status = %s ) AND ( %s = %s OR tool = %s ) ORDER BY id DESC LIMIT %d', $table, $since, $status, 'any', $status, $tool, '', $tool, $limit ), ARRAY_A );
					$out  = array();
					foreach ( (array) $rows as $row ) {
						$out[] = array(
							'when'    => (string) $row['created_at'] . ' UTC',
							'app'     => mb_substr( (string) $row['client'], 0, 60 ),
							'tool'    => (string) $row['tool'],
							'status'  => (string) $row['status'],
							'item'    => (string) $row['object_ref'],
							'message' => \HandyMCP\Support\Redactor::scrub_string( mb_substr( (string) $row['summary'], 0, 500 ) ),
							'ms'      => (int) $row['duration_ms'],
						);
					}
					return array( 'entries' => $out, 'count' => count( $out ) );
				},
			)
		);

		$r->add(
			array(
				'name'        => 'history_changes',
				'group'       => 'assistant',
				'title'       => 'Show what a change did',
				'description' => 'Before and now, field by field, for one change from history_list (history_id): title, text, SEO fields, prices, terms and settings. Use it to tell the user exactly what was changed, or to check a change before undoing it.',
				'cap'         => 'edit_posts',
				'input'       => array(
					'required'   => array( 'history_id' ),
					'properties' => array(
						'history_id' => array( 'type' => 'string', 'pattern' => '^op_[0-9]{12}_[a-f0-9]{6}$' ),
					),
				),
				'run'         => static function ( array $a ) {
					$op    = (string) $a['history_id'];
					$owner = History::op_user( $op );
					if ( ! $owner ) {
						return new \WP_Error( 'not_found', 'This change is no longer in the history.' );
					}
					if ( ! current_user_can( 'manage_options' ) && get_current_user_id() !== $owner ) {
						return new \WP_Error( 'forbidden', 'You can only view your own changes.' );
					}
					return array( 'history_id' => $op, 'items' => \HandyMCP\Support\ChangeView::for_ai( $op ) );
				},
			)
		);

		$r->add(
			array(
				'name'        => 'history_list',
				'group'       => 'assistant',
				'title'       => 'List recent changes (undo history)',
				'description' => 'Changes made through MCP, newest first. Each has a history_id; changes from the same conversation share a task_id. Pass post_id for one page.',
				'cap'         => 'edit_posts',
				'input'       => array(
					'properties' => array(
						'post_id' => array( 'type' => 'integer', 'minimum' => 1 ),
						'limit'   => array( 'type' => 'integer', 'minimum' => 1, 'maximum' => 100, 'default' => 20 ),
					),
				),
				'run'         => static function ( array $a ) {
					$limit = (int) $a['limit'];
					$post  = (int) ( $a['post_id'] ?? 0 );
					if ( current_user_can( 'manage_options' ) ) {
						$rows = History::operations( $limit, 0, $post );
					} else {
						// Non-administrators only see their own changes.
						$rows = array();
						$me   = get_current_user_id();
						for ( $offset = 0; $offset < 1000 && count( $rows ) < $limit; $offset += 100 ) {
							$page = History::operations( 100, $offset, $post );
							foreach ( $page as $row ) {
								if ( (int) ( $row['user_id'] ?? 0 ) === $me ) {
									$rows[] = $row;
								}
							}
							if ( count( $page ) < 100 ) {
								break;
							}
						}
						$rows = array_slice( $rows, 0, $limit );
					}
					return array(
						'changes' => array_map(
							static function ( $r ) {
								return array( 'history_id' => $r['op_id'], 'task_id' => $r['task'] ?? '', 'when' => $r['created_at'], 'tool' => $r['tool'], 'touched' => mb_substr( (string) $r['labels'], 0, 300 ), 'undone' => (bool) $r['reverted_at'] );
							},
							$rows
						),
					);
				},
			)
		);

		$r->add(
			array(
				'name'        => 'history_revert',
				'group'       => 'assistant',
				'title'       => 'Undo changes',
				'description' => 'Undo one change (history_id), every change from one conversation (task_id), or every change made to one page or post (post_id, optionally only since a time). Posts, pages, builder layouts, templates, media, menus and terms are restored. The last 20 changes are kept. The undo is recorded too, so it can be redone by undoing it.',
				'write'       => true,
				'cap'         => 'edit_posts',
				'input'       => array(
					'properties' => array(
						'history_id' => array( 'type' => 'string', 'pattern' => '^op_[0-9]{12}_[a-f0-9]{6}$' ),
						'task_id'    => array( 'type' => 'string', 'pattern' => '^[a-z0-9-]{4,40}$' ),
						'post_id'    => array( 'type' => 'integer', 'minimum' => 1 ),
						'since'      => array( 'type' => 'string', 'description' => 'With post_id: only undo changes after this time (YYYY-MM-DD HH:MM:SS, UTC).' ),
					),
				),
				'run'         => static function ( array $a, $identity = null ) {
					global $wpdb;
					if ( ! empty( $a['history_id'] ) ) {
						$ops = array( $a['history_id'] );
					} elseif ( ! empty( $a['task_id'] ) || ! empty( $a['post_id'] ) ) {
						$ops = History::ops_for( (string) ( $a['task_id'] ?? '' ), (int) ( $a['post_id'] ?? 0 ), (string) ( $a['since'] ?? '' ) );
						if ( ! $ops ) {
							return new \WP_Error( 'nothing_to_undo', 'No changes found to undo.' );
						}
					} else {
						return new \WP_Error( 'missing_target', 'Pass history_id, task_id or post_id.' );
					}
					$t     = \HandyMCP\Database\Installer::table( 'history' );
					$in    = implode( ',', array_fill( 0, count( $ops ), '%s' ) );
					$owners = array_map( 'intval', (array) $wpdb->get_col( $wpdb->prepare( "SELECT DISTINCT user_id FROM %i WHERE op_id IN ($in)", array_merge( array( $t ), $ops ) ) ) ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching, WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- custom table; $in is placeholders built from count($ops).
					if ( ! current_user_can( 'manage_options' ) && array_diff( $owners, array( get_current_user_id() ) ) ) {
						return new \WP_Error( 'forbidden', 'Only an administrator can undo another user\'s change.' );
					}
					// Free records posts, pages, media, menus and terms only. Other changes were made with Pro.
					$kinds = array_unique( (array) $wpdb->get_col( $wpdb->prepare( "SELECT DISTINCT kind FROM %i WHERE op_id IN ($in)", array_merge( array( $t ), $ops ) ) ) ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching, WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- custom table; $in is placeholders built from count($ops).
					if ( array_diff( $kinds, array( 'post', 'created_post', 'term', 'created_term' ) ) ) {
						return new \WP_Error( 'not_supported', 'Some of these changes were made with HandyMCP Pro (settings, files, plugins or users) and can only be undone there.' );
					}
					return 1 === count( $ops ) ? History::revert( $ops[0] ) : History::revert_many( $ops );
				},
			)
		);

		// ChatGPT connectors (deep research / company knowledge) call these two by name.
		$r->add(
			array(
				'name'        => 'search',
				'group'       => 'assistant',
				'title'       => 'Search site content',
				'description' => 'Search published and draft posts, pages and products. Returns ids for fetch.',
				'cap'         => 'edit_posts',
				'input'       => array( 'required' => array( 'query' ), 'properties' => array( 'query' => array( 'type' => 'string' ) ) ),
				'run'         => static function ( array $a ) {
					$q   = new \WP_Query( array( 's' => $a['query'], 'post_type' => array_values( get_post_types( array( 'public' => true ) ) ), 'post_status' => array( 'publish', 'draft', 'private', 'pending' ), 'perm' => 'readable', 'posts_per_page' => 10 ) );
					$out = array();
					foreach ( $q->posts as $p ) {
						if ( ! current_user_can( 'read_post', $p->ID ) ) {
							continue;
						}
						$out[] = array( 'id' => (string) $p->ID, 'title' => get_the_title( $p ), 'url' => get_permalink( $p ) );
					}
					return array( 'results' => $out );
				},
			)
		);
		$r->add(
			array(
				'name'        => 'fetch',
				'group'       => 'assistant',
				'title'       => 'Fetch a post or page',
				'description' => 'Full text of a post, page or product by id (from search), or by its address on this site (url).',
				'cap'         => 'edit_posts',
				'input'       => array( 'properties' => array( 'id' => array( 'type' => 'string' ), 'url' => array( 'type' => 'string', 'maxLength' => 2000 ) ) ),
				'run'         => static function ( array $a ) {
					$id = (int) ( $a['id'] ?? 0 );
					if ( ! $id && ! empty( $a['url'] ) ) {
						$host = strtolower( (string) wp_parse_url( (string) $a['url'], PHP_URL_HOST ) );
						if ( '' !== $host && strtolower( (string) wp_parse_url( home_url(), PHP_URL_HOST ) ) !== $host ) {
							return new \WP_Error( 'not_found', 'That address is not on this site.' );
						}
						$id = url_to_postid( (string) $a['url'] );
						if ( ! $id && '/' === untrailingslashit( (string) wp_parse_url( (string) $a['url'], PHP_URL_PATH ) ) . '/' ) {
							$id = (int) get_option( 'page_on_front' );
						}
					}
					if ( ! $id ) {
						return new \WP_Error( 'not_found', 'Pass the id from search, or the address of a page on this site.' );
					}
					$p = Util::post( $id, null, 'read' );
					if ( is_wp_error( $p ) ) {
						return $p;
					}
					// Form configs and stored messages (Flamingo, form plugins), non-public types and password-protected posts need edit rights.
					$config = array( 'flamingo_inbound', 'flamingo_outbound', 'flamingo_contact', 'wpcf7_contact_form', 'wpforms', 'metform-form', 'metform-entry', 'jet-form-builder', 'jet-fb-records', 'forminator_forms', 'nf_sub', 'frm_form_actions' );
					if ( ( ! is_post_type_viewable( $p->post_type ) || in_array( $p->post_type, $config, true ) || '' !== (string) $p->post_password ) && ! current_user_can( 'edit_post', $p->ID ) ) {
						return new \WP_Error( 'forbidden', 'You cannot read this item.' );
					}
					$text = trim( preg_replace( '/\s+/', ' ', wp_strip_all_tags( do_blocks( $p->post_content ) ) ) );
					if ( '' === $text && 'builder' === get_post_meta( $p->ID, '_elementor_edit_mode', true ) ) {
						$text = wp_strip_all_tags( (string) get_post_meta( $p->ID, '_elementor_data', true ) );
					}
					return array( 'id' => (string) $p->ID, 'title' => get_the_title( $p ), 'text' => mb_substr( $text, 0, 20000 ), 'url' => get_permalink( $p ), 'metadata' => array( 'type' => $p->post_type, 'status' => $p->post_status, 'builder' => Util::builder_of( $p->ID ), 'modified' => Util::modified( $p ) ) );
				},
			)
		);
	}

	/**
	 * Replace "$N.path" strings with values from earlier results.
	 *
	 * @param mixed                            $value   Value.
	 * @param array<int, array<string, mixed>> $results Results.
	 * @return mixed
	 */
	private static function substitute( $value, array $results ) {
		if ( is_array( $value ) ) {
			foreach ( $value as $k => $v ) {
				$value[ $k ] = self::substitute( $v, $results );
			}
			return $value;
		}
		if ( is_string( $value ) && preg_match( '/^\$(\d+)\.([A-Za-z0-9_.]+)$/', $value, $m ) && isset( $results[ (int) $m[1] ] ) ) {
			$cur = $results[ (int) $m[1] ];
			foreach ( explode( '.', $m[2] ) as $part ) {
				if ( is_array( $cur ) && array_key_exists( $part, $cur ) ) {
					$cur = $cur[ $part ];
				} else {
					return $value;
				}
			}
			return $cur;
		}
		return $value;
	}
}