<?php
/**
 * Plugin Name:       ARWP Agents
 * Plugin URI:        https://wordpress.org/plugins/arwp-agents/
 * Description:       Self-hosted AI chat agents for WordPress, using your own OpenRouter API key.
 * Version:           1.6.1
 * Requires at least: 6.2
 * Requires PHP:      7.4
 * Author:            ARWP
 * Author URI:        https://profiles.wordpress.org/artisanswp/
 * License:           GPL-2.0-or-later
 * License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 * Text Domain:       arwp-agents
 * Domain Path:       /languages
 *
 * @package ARWP_Agents
 */

// If this file is called directly, abort.
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

// Define plugin constants.
define( 'ARWP_VERSION', '1.6.1' );
define( 'ARWP_PATH', plugin_dir_path( __FILE__ ) );
define( 'ARWP_URL', plugin_dir_url( __FILE__ ) );
define( 'ARWP_BASENAME', plugin_basename( __FILE__ ) );

// Include required classes.
require_once ARWP_PATH . 'includes/class-arwp-activator.php';
require_once ARWP_PATH . 'includes/class-arwp-settings.php';
require_once ARWP_PATH . 'includes/class-arwp-cpt.php';
require_once ARWP_PATH . 'includes/class-arwp-api.php';
require_once ARWP_PATH . 'includes/class-arwp-shortcode.php';
require_once ARWP_PATH . 'includes/class-arwp-conversations.php';

/**
 * Hard ceiling on how many past messages are replayed to the model.
 *
 * Without a cap an old conversation resends its entire history on every turn, which
 * grows the bill and the request size without bound.
 *
 * @return int
 */
function arwp_default_history_limit() {
	return (int) apply_filters( 'arwp_default_history_limit', 40 );
}

/**
 * Maximum characters accepted in a single chat message. 0 disables the check.
 *
 * @return int
 */
function arwp_max_message_chars() {
	return (int) apply_filters( 'arwp_max_message_chars', 8000 );
}

/**
 * Seconds a visitor must wait between messages in the same session.
 *
 * @return int
 */
function arwp_default_cooldown() {
	return (int) apply_filters( 'arwp_default_cooldown', 5 );
}

/**
 * Max chat turns per visitor IP, per agent, per hour. 0 disables the cap.
 *
 * @return int
 */
function arwp_default_rate_limit_per_ip() {
	return (int) apply_filters( 'arwp_default_rate_limit_per_ip', 30 );
}

/**
 * Max chat turns across all visitors of one agent per hour. 0 disables the cap.
 *
 * @return int
 */
function arwp_default_rate_limit_per_agent() {
	return (int) apply_filters( 'arwp_default_rate_limit_per_agent', 200 );
}

/**
 * Read a non-negative int from post meta, using $default when the field was never saved.
 *
 * @param mixed $raw      Raw meta value.
 * @param int   $fallback Fallback when empty.
 * @return int
 */
function arwp_meta_int( $raw, $fallback ) {
	if ( '' === $raw || false === $raw || null === $raw ) {
		return (int) $fallback;
	}

	return max( 0, (int) $raw );
}

/**
 * Who may open this agent: ok, login, or denied.
 *
 * People who can edit the agent can always open it. Missing or unknown
 * access meta stays public, which is how agents worked before this setting.
 *
 * @param int $agent_id Agent post ID.
 * @return string ok|login|denied
 */
function arwp_agent_access_state( $agent_id ) {
	$agent_id = (int) $agent_id;

	if ( current_user_can( 'edit_post', $agent_id ) ) {
		return 'ok';
	}

	$access = get_post_meta( $agent_id, '_arwp_access', true );
	if ( ! in_array( $access, array( 'public', 'logged_in', 'roles' ), true ) ) {
		$access = 'public';
	}

	if ( 'public' === $access ) {
		return 'ok';
	}

	if ( ! is_user_logged_in() ) {
		return 'login';
	}

	if ( 'logged_in' === $access ) {
		return 'ok';
	}

	$allowed = get_post_meta( $agent_id, '_arwp_access_roles', true );
	if ( ! is_array( $allowed ) ) {
		$allowed = array();
	}

	$user = wp_get_current_user();
	if ( array_intersect( $allowed, (array) $user->roles ) ) {
		return 'ok';
	}

	return 'denied';
}

/**
 * Whether the current visitor may use this agent.
 *
 * @param int $agent_id Agent post ID.
 * @return bool
 */
function arwp_visitor_can_use_agent( $agent_id ) {
	$can = ( 'ok' === arwp_agent_access_state( $agent_id ) );

	return (bool) apply_filters( 'arwp_visitor_can_use_agent', $can, $agent_id );
}

/**
 * Whether a stored pattern is safe to keep and run.
 *
 * @param string $pattern Pattern without delimiters.
 * @return bool
 */
function arwp_pattern_is_safe( $pattern ) {
	if ( ! is_string( $pattern ) ) {
		return false;
	}

	$length = function_exists( 'mb_strlen' ) ? mb_strlen( $pattern ) : strlen( $pattern );
	if ( $length < 1 || $length > 80 ) {
		return false;
	}

	if ( false !== strpos( $pattern, '~' ) || false !== strpos( $pattern, "\0" ) ) {
		return false;
	}

	// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged -- Invalid patterns must be rejected, not thrown.
	return false !== @preg_match( '~' . $pattern . '~iu', '' );
}

/**
 * Match one stored pattern against a visitor message.
 *
 * Backtracking and recursion are capped so a pattern cannot stall PHP.
 * A pattern that hits the cap does not match.
 *
 * @param string $pattern Pattern without delimiters.
 * @param string $subject Visitor message.
 * @return bool
 */
function arwp_pattern_matches( $pattern, $subject ) {
	if ( ! arwp_pattern_is_safe( $pattern ) ) {
		return false;
	}

	$backtrack = ini_get( 'pcre.backtrack_limit' );
	$recursion = ini_get( 'pcre.recursion_limit' );
	// phpcs:disable WordPress.PHP.IniSet.Risky, Squiz.PHP.DiscouragedFunctions.Discouraged -- The cap is restored before this function returns.
	ini_set( 'pcre.backtrack_limit', '20000' );
	ini_set( 'pcre.recursion_limit', '10000' );
	// phpcs:enable WordPress.PHP.IniSet.Risky, Squiz.PHP.DiscouragedFunctions.Discouraged

	// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged -- A pattern that overruns the cap returns false.
	$matched = @preg_match( '~' . $pattern . '~iu', (string) $subject );

	// phpcs:disable WordPress.PHP.IniSet.Risky, Squiz.PHP.DiscouragedFunctions.Discouraged -- Restores the limits captured above.
	if ( false !== $backtrack ) {
		ini_set( 'pcre.backtrack_limit', (string) $backtrack );
	}
	if ( false !== $recursion ) {
		ini_set( 'pcre.recursion_limit', (string) $recursion );
	}
	// phpcs:enable WordPress.PHP.IniSet.Risky, Squiz.PHP.DiscouragedFunctions.Discouraged

	return 1 === $matched;
}

/**
 * Whether this visitor message matches a phrase or pattern on the agent.
 *
 * @param int    $agent_id Agent post ID.
 * @param string $message  Visitor message.
 * @return bool
 */
function arwp_message_is_blocked( $agent_id, $message ) {
	$message = (string) $message;
	$phrases = get_post_meta( $agent_id, '_arwp_blocked_phrases', true );
	if ( ! is_array( $phrases ) ) {
		$phrases = array();
	}

	foreach ( $phrases as $phrase ) {
		if ( ! is_string( $phrase ) || '' === $phrase ) {
			continue;
		}

		$found = function_exists( 'mb_stripos' ) ? mb_stripos( $message, $phrase ) : stripos( $message, $phrase );
		if ( false !== $found ) {
			return true;
		}
	}

	$patterns = get_post_meta( $agent_id, '_arwp_blocked_patterns', true );
	if ( ! is_array( $patterns ) ) {
		$patterns = array();
	}

	foreach ( $patterns as $pattern ) {
		if ( ! is_string( $pattern ) || '' === $pattern ) {
			continue;
		}

		if ( arwp_pattern_matches( $pattern, $message ) ) {
			return true;
		}
	}

	return false;
}

/**
 * Hide emails, phone numbers, and IP addresses when Chats details are off.
 *
 * Display only. Callers must not write the result back to the database.
 *
 * @param string $text Original text.
 * @return string
 */
function arwp_redact_personal_details( $text ) {
	if ( ! is_string( $text ) ) {
		return '';
	}

	if ( '1' === (string) get_option( 'arwp_chats_show_details', '0' ) ) {
		return $text;
	}

	$hidden = '[hidden]';
	$text   = preg_replace( '/[A-Za-z0-9._%+\-]+@[A-Za-z0-9.\-]+\.[A-Za-z]{2,}/', $hidden, $text );
	if ( ! is_string( $text ) ) {
		return '';
	}

	$text = preg_replace( '/\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b/', $hidden, $text );
	if ( ! is_string( $text ) ) {
		return '';
	}

	$text = preg_replace( '/(?<!\w)\+?\d(?:[\s().\-]*\d){9,}(?!\w)/', $hidden, $text );
	if ( ! is_string( $text ) ) {
		return '';
	}

	return $text;
}

/**
 * Capabilities for the agent post type.
 *
 * These must be unique names. Mapping them onto manage_options makes WordPress
 * treat manage_options as a post meta capability, which hides this menu and
 * breaks other administrator checks.
 *
 * @return array<string, string>
 */
function arwp_agent_capabilities() {
	return array(
		'edit_post'              => 'edit_arwp_agent',
		'read_post'              => 'read_arwp_agent',
		'delete_post'            => 'delete_arwp_agent',
		'edit_posts'             => 'edit_arwp_agents',
		'edit_others_posts'      => 'edit_others_arwp_agents',
		'delete_posts'           => 'delete_arwp_agents',
		'publish_posts'          => 'publish_arwp_agents',
		'read_private_posts'     => 'read_private_arwp_agents',
		'delete_private_posts'   => 'delete_private_arwp_agents',
		'delete_published_posts' => 'delete_published_arwp_agents',
		'delete_others_posts'    => 'delete_others_arwp_agents',
		'edit_private_posts'     => 'edit_private_arwp_agents',
		'edit_published_posts'   => 'edit_published_arwp_agents',
		'create_posts'           => 'edit_arwp_agents',
	);
}

/**
 * Give administrators the agent capabilities. Editors do not receive them.
 */
function arwp_grant_agent_caps_to_administrators() {
	$role = get_role( 'administrator' );
	if ( ! $role ) {
		return;
	}

	foreach ( array_unique( arwp_agent_capabilities() ) as $cap ) {
		if ( ! $role->has_cap( $cap ) ) {
			$role->add_cap( $cap );
		}
	}

	$user = wp_get_current_user();
	if ( $user instanceof WP_User && in_array( 'administrator', (array) $user->roles, true ) ) {
		$user->get_role_caps();
	}
}
add_action( 'init', 'arwp_grant_agent_caps_to_administrators', 5 );

/**
 * The code that runs during plugin activation.
 */
function arwp_activate_plugin() {
	ARWP_Activator::activate();
}
register_activation_hook( __FILE__, 'arwp_activate_plugin' );

/**
 * Development paths that are omitted from the release zip.
 *
 * Plugin Check scans the installed directory. These match .distignore so the
 * local result matches the package WordPress.org would receive.
 *
 * @param array $directories Directories to skip.
 * @return array
 */
function arwp_plugin_check_ignore_directories( $directories ) {
	return array_merge( $directories, array( 'tests', '.github' ) );
}
add_filter( 'wp_plugin_check_ignore_directories', 'arwp_plugin_check_ignore_directories' );

/**
 * Development files that are omitted from the release zip.
 *
 * @param array $files Files to skip.
 * @return array
 */
function arwp_plugin_check_ignore_files( $files ) {
	return array_merge(
		$files,
		array(
			'.distignore',
			'.gitignore',
			'.phpcs.cache',
			'.phpunit.result.cache',
			'phpcs.xml.dist',
			'phpunit.xml.dist',
		)
	);
}
add_filter( 'wp_plugin_check_ignore_files', 'arwp_plugin_check_ignore_files' );

/**
 * Initialize all core components of the plugin.
 *
 * Translations ship through the Domain Path header. WordPress loads them.
 */
function arwp_init_plugin() {
	if ( get_option( 'arwp_db_version' ) !== '1.6' ) {
		ARWP_Activator::activate();
		ARWP_Activator::cleanup_removed_features();
		update_option( 'arwp_db_version', '1.6' );
	}

	$cpt = new ARWP_CPT();
	$cpt->init();

	$settings = new ARWP_Settings();
	$settings->init();

	$api = new ARWP_API();
	$api->init();

	$shortcode = new ARWP_Shortcode();
	$shortcode->init();

	$conversations = new ARWP_Conversations();
	$conversations->init();
}
add_action( 'plugins_loaded', 'arwp_init_plugin' );