<?php
/**
 * Public API Handlers for Agentorie Chat.
 *
 * Handles AJAX requests from the visitor widget.
 *
 * @package    Agentorie_Chat
 * @subpackage Agentorie_Chat/includes
 * @since      1.0.0
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * API Public Handlers class.
 *
 * @since 1.0.0
 */
class Agentorie_API_Public {

	/**
	 * Single instance.
	 *
	 * @var Agentorie_API_Public
	 */
	private static $instance = null;

	/**
	 * Get singleton instance.
	 *
	 * @return Agentorie_API_Public
	 */
	public static function get_instance() {
		if ( null === self::$instance ) {
			self::$instance = new self();
		}
		return self::$instance;
	}

	/**
	 * Verify public nonce and handle expiration.
	 *
	 * @return bool True if valid, sends error response and exits if invalid.
	 */
	private function verify_nonce_or_fail() {
		$nonce_check = Agentorie_API_Helpers::verify_public_nonce();

		if ( true === $nonce_check ) {
			// Per-IP flood protection for all public proxy endpoints.
			// Administrators and excluded test IPs bypass this automatically.
			if ( ! Agentorie_API_Helpers::check_ip_rate_limit( 'global', Agentorie_API_Helpers::RATE_LIMIT_IP_GLOBAL ) ) {
				Agentorie_API_Helpers::send_error( __( 'Too many requests. Please slow down and try again.', 'agentorie-chat' ), 429 );
			}
			return true;
		}

		if ( 'expired' === $nonce_check ) {
			// Nonce expired - tell client to refresh and retry.
			Agentorie_API_Helpers::send_nonce_expired();
		}

		// No nonce or invalid.
		Agentorie_API_Helpers::send_error( __( 'Security check failed.', 'agentorie-chat' ), 403 );
		return false; // Never reached due to wp_send_json_error exit.
	}

	/**
	 * Handle send message request.
	 *
	 * @return void
	 */
	public function handle_send_message() {
		$this->verify_nonce_or_fail();

		$session_id = Agentorie_API_Helpers::get_input( 'session_id', '', 'key' );
		$message    = Agentorie_API_Helpers::get_input( 'message', '', 'textarea' );

		if ( empty( $session_id ) || empty( $message ) ) {
			Agentorie_API_Helpers::send_error( __( 'Missing required data.', 'agentorie-chat' ) );
		}

		if ( ! Agentorie_Session::validate_session_id( $session_id ) ) {
			Agentorie_API_Helpers::send_error( __( 'Invalid session.', 'agentorie-chat' ) );
		}

		$message = Agentorie_API_Helpers::sanitize_message( $message );
		if ( empty( $message ) ) {
			Agentorie_API_Helpers::send_error( __( 'Invalid message.', 'agentorie-chat' ) );
		}

		if ( ! Agentorie_API_Helpers::check_message_rate_limit( $session_id ) ) {
			Agentorie_API_Helpers::send_error( __( 'Too many messages. Please wait.', 'agentorie-chat' ), 429 );
		}

		// Per-IP guard on the AI path so rotating session IDs cannot flood the backend.
		if ( ! Agentorie_API_Helpers::check_ip_rate_limit( 'chat', Agentorie_API_Helpers::RATE_LIMIT_IP_CHAT ) ) {
			Agentorie_API_Helpers::send_error( __( 'Too many messages. Please wait.', 'agentorie-chat' ), 429 );
		}

		$honeypot = Agentorie_API_Helpers::get_input( 'website', '', 'text' );
		if ( ! empty( $honeypot ) ) {
			Agentorie_API_Helpers::send_success( array( 'message' => __( 'Thank you for your message.', 'agentorie-chat' ) ) );
		}

		$context = array(
			'visitor_id'  => Agentorie_API_Helpers::get_input( 'visitor_id', '', 'text' ),
			'current_url' => Agentorie_API_Helpers::get_input( 'current_url', '', 'url' ),
			'page_title'  => Agentorie_API_Helpers::get_input( 'page_title', '', 'text' ),
			'referrer'    => esc_url_raw( wp_get_referer() ? wp_get_referer() : '' ),
			'user_agent'  => Agentorie_Session::get_user_agent(),
		);

		// Check admin_takeover directly from database (source of truth).
		// This ensures we don't miss takeover even if transient is stale.
		$db_session        = Agentorie_Database::get_session( $session_id );
		$is_admin_takeover = $db_session && ! empty( $db_session['admin_takeover'] );

		$session = Agentorie_Session::get_or_create( $session_id );
		$session->update_visitor_info( $context['visitor_id'], $context['current_url'], $context['page_title'] );

		// Sync takeover status from DB to session object.
		if ( $is_admin_takeover && ! $session->is_admin_takeover() ) {
			$admin_id = isset( $db_session['admin_user_id'] ) ? $db_session['admin_user_id'] : null;
			$session->set_admin_takeover( true, $admin_id );
			$session->save();
		}

		$user_message_id = Agentorie_Database::insert_message(
			array(
				'session_id' => $session_id,
				'role'       => 'user',
				'message'    => $message,
			)
		);

		// If admin has taken over, don't call AI - just save message and return.
		if ( $is_admin_takeover ) {
			$session->increment_messages();
			$session->set_last_message( $message );
			$session->save();
			$session->sync_to_database();

			Agentorie_API_Helpers::send_success(
				array(
					'message'        => null,
					'admin_takeover' => true,
					'action'         => 'wait_admin',
					'message_id'     => $user_message_id,
				)
			);
			return; // Explicit return for safety.
		}

		$exclude_from_stats = Agentorie_API_Helpers::is_excluded_ip();
		$saas               = Agentorie_API_SaaS::get_instance();
		$response           = $saas->send_message( $session_id, $message, $context, $exclude_from_stats );

		if ( is_wp_error( $response ) ) {
			Agentorie_API_Helpers::send_error( __( 'Sorry, I am experiencing a technical issue. Please try again.', 'agentorie-chat' ) );
		}

		$ai_message = isset( $response['response'] ) ? $response['response'] : ( isset( $response['message'] ) ? $response['message'] : '' );
		$flags      = isset( $response['flags'] ) ? $response['flags'] : array();

		if ( ! empty( $flags['negotiate_detected'] ) || false !== strpos( $ai_message, '[NEGOTIATE_DETECTED]' ) ) {
			$ai_message = str_replace( '[NEGOTIATE_DETECTED]', '', $ai_message );
			$ai_message = trim( $ai_message );
			if ( ! empty( $flags['negotiate_detected'] ) ) {
				$session->set_negotiate_detected( true );
			}
		}

		if ( false !== strpos( $ai_message, '[HUMAN_REQUESTED]' ) ) {
			$ai_message = str_replace( '[HUMAN_REQUESTED]', '', $ai_message );
			$ai_message = trim( $ai_message );
		}
		if ( ! empty( $flags['human_requested'] ) ) {
			$session->set_human_requested( true );
		}

		if ( preg_match( '/\[LEAD_COLLECTED:(\{.*?\})\]/s', $ai_message, $lead_matches ) ) {
			$ai_message = preg_replace( '/\[LEAD_COLLECTED:\{.*?\}\]/s', '', $ai_message );
			$ai_message = trim( $ai_message );

			$lead_data = json_decode( $lead_matches[1], true );
			if ( $lead_data && is_array( $lead_data ) ) {
				$this->process_lead_collection( $lead_data, $session_id, $context );
			}
		}

		// Process lead collection from flags (new format from SaaS).
		// lead_data format: ['name' => '...', 'email' => '...', 'phone' => '...', 'message' => '...'].
		if ( ! empty( $flags['lead_collected'] ) && ! empty( $flags['lead_data'] ) && is_array( $flags['lead_data'] ) ) {
			$this->process_lead_collection( $flags['lead_data'], $session_id, $context );
		}

		// Clean any remaining LEAD_INFO tags from message (in case SaaS didn't fully clean them).
		$ai_message = preg_replace( '/\s*\[LEAD_INFO:[^\]]+\]\s*/', ' ', $ai_message );
		$ai_message = trim( preg_replace( '/\s+/', ' ', $ai_message ) );

		$bot_message_id = Agentorie_Database::insert_message(
			array(
				'session_id' => $session_id,
				'role'       => 'assistant',
				'message'    => $ai_message,
			)
		);

		$session->increment_messages();
		$session->set_last_message( $ai_message );
		$session->save();
		$session->sync_to_database();

		$test_mode      = $exclude_from_stats || ( isset( $response['test_mode'] ) && $response['test_mode'] );
		$test_remaining = isset( $response['test_remaining'] ) ? (int) $response['test_remaining'] : null;

		$result = array(
			'message'        => $ai_message,
			'message_id'     => $bot_message_id,
			'admin_takeover' => false,
			'flags'          => $flags,
			'test_mode'      => $test_mode,
		);

		if ( $test_mode && null !== $test_remaining ) {
			$result['test_remaining'] = $test_remaining;
		}

		if ( isset( $response['onboarding_mode'] ) && $response['onboarding_mode'] ) {
			$result['onboarding_mode'] = true;
		}

		Agentorie_API_Helpers::send_success( $result );
	}

	/**
	 * Handle get history request.
	 *
	 * @return void
	 */
	public function handle_get_history() {
		$this->verify_nonce_or_fail();

		$session_id = Agentorie_API_Helpers::get_input( 'session_id', '', 'key' );

		if ( empty( $session_id ) || ! Agentorie_Session::validate_session_id( $session_id ) ) {
			Agentorie_API_Helpers::send_error( __( 'Invalid session.', 'agentorie-chat' ) );
			return;
		}

		$existing_session = Agentorie_Database::get_session( $session_id );

		if ( ! $existing_session ) {
			Agentorie_API_Helpers::send_success(
				array(
					'history'        => array(),
					'admin_takeover' => false,
				)
			);
			return;
		}

		$session = Agentorie_Session::get_or_create( $session_id );
		$session->update_visitor_info(
			Agentorie_API_Helpers::get_input( 'visitor_id', '', 'text' ),
			Agentorie_API_Helpers::get_input( 'current_url', '', 'url' ),
			Agentorie_API_Helpers::get_input( 'page_title', '', 'text' )
		);
		$session->save();
		$session->sync_to_database(); // FIX: Sync to DB so LiveChat admin sees visitor_id/current_url.

		$messages = Agentorie_Database::get_messages( $session_id );

		Agentorie_API_Helpers::send_success(
			array(
				'history'        => Agentorie_Database::dates_to_iso8601( $messages ),
				'admin_takeover' => $session->is_admin_takeover(),
			)
		);
	}

	/**
	 * Handle send contact request.
	 *
	 * @return void
	 */
	public function handle_send_contact() {
		$this->verify_nonce_or_fail();

		$session_id = Agentorie_API_Helpers::get_input( 'session_id', '', 'key' );
		$name       = Agentorie_API_Helpers::get_input( 'client_nom', '', 'text' );
		$email      = Agentorie_API_Helpers::get_input( 'client_email', '', 'email' );
		$phone      = Agentorie_API_Helpers::get_input( 'client_telephone', '', 'text' );
		$message    = Agentorie_API_Helpers::get_input( 'message_client', '', 'textarea' );

		if ( empty( $session_id ) || empty( $name ) ) {
			Agentorie_API_Helpers::send_error( __( 'Name is required.', 'agentorie-chat' ) );
		}

		if ( ! Agentorie_Session::validate_session_id( $session_id ) ) {
			Agentorie_API_Helpers::send_error( __( 'Invalid session.', 'agentorie-chat' ) );
		}

		if ( empty( $email ) && empty( $phone ) ) {
			Agentorie_API_Helpers::send_error( __( 'Please provide at least an email or phone number.', 'agentorie-chat' ) );
		}

		if ( ! empty( $email ) && ! is_email( $email ) ) {
			Agentorie_API_Helpers::send_error( __( 'Invalid email format.', 'agentorie-chat' ) );
		}

		if ( ! Agentorie_API_Helpers::check_rate_limit( $session_id . '_contact', 1, 600 ) ) {
			Agentorie_API_Helpers::send_error( __( 'You have already sent a request recently.', 'agentorie-chat' ) );
		}

		if ( Agentorie_API_Helpers::is_spam_content( $message ) ) {
			Agentorie_API_Helpers::send_error( __( 'Your message contains suspicious content.', 'agentorie-chat' ) );
		}

		Agentorie_Database::insert_contact(
			array(
				'session_id' => $session_id,
				'name'       => $name,
				'email'      => $email,
				'phone'      => $phone,
				'message'    => $message,
			)
		);

		Agentorie_API_Helpers::send_contact_notification( $session_id, $name, $email, $phone, $message );

		Agentorie_API_Helpers::send_success( array( 'message' => __( 'Your request has been sent! We will contact you shortly.', 'agentorie-chat' ) ) );
	}

	/**
	 * Handle speech to text request.
	 *
	 * The SaaS backend handles all authorization:
	 * - Active subscription with STT feature
	 * - Demo mode with remaining quota
	 *
	 * WordPress plugin simply forwards the request.
	 */
	public function handle_speech_to_text() {
		$this->verify_nonce_or_fail();

		// Per-IP guard on the voice path (STT and TTS share this budget; each call hits the voice API).
		if ( ! Agentorie_API_Helpers::check_ip_rate_limit( 'voice', Agentorie_API_Helpers::RATE_LIMIT_IP_VOICE ) ) {
			Agentorie_API_Helpers::send_error( __( 'Too many requests. Please slow down and try again.', 'agentorie-chat' ), 429 );
		}

		$audio    = Agentorie_API_Helpers::get_input( 'audio', '', 'base64' );
		$language = Agentorie_API_Helpers::get_input( 'language', 'fr-FR', 'text' );

		if ( empty( $audio ) ) {
			Agentorie_API_Helpers::send_error( __( 'No audio data provided.', 'agentorie-chat' ) );
		}

		$saas     = Agentorie_API_SaaS::get_instance();
		$response = $saas->speech_to_text( $audio, $language );

		if ( is_wp_error( $response ) ) {
			// SaaS returns specific error if subscription/demo quota exceeded.
			$error_message = $response->get_error_message();
			Agentorie_API_Helpers::send_error( $error_message ? $error_message : __( 'Speech recognition failed.', 'agentorie-chat' ) );
		}

		Agentorie_API_Helpers::send_success( array( 'text' => isset( $response['text'] ) ? $response['text'] : '' ) );
	}

	/**
	 * Handle text to speech request.
	 *
	 * The SaaS backend handles all authorization:
	 * - Active subscription with TTS feature
	 * - Demo mode with remaining quota
	 *
	 * WordPress plugin simply forwards the request.
	 */
	public function handle_text_to_speech() {
		$this->verify_nonce_or_fail();

		// Per-IP guard on the voice path (STT and TTS share this budget; each call hits the voice API).
		if ( ! Agentorie_API_Helpers::check_ip_rate_limit( 'voice', Agentorie_API_Helpers::RATE_LIMIT_IP_VOICE ) ) {
			Agentorie_API_Helpers::send_error( __( 'Too many requests. Please slow down and try again.', 'agentorie-chat' ), 429 );
		}

		$text     = Agentorie_API_Helpers::get_input( 'text', '', 'textarea' );
		$language = Agentorie_API_Helpers::get_input( 'language', 'fr-FR', 'text' );

		if ( empty( $text ) ) {
			Agentorie_API_Helpers::send_error( __( 'No text provided.', 'agentorie-chat' ) );
		}

		$saas     = Agentorie_API_SaaS::get_instance();
		$response = $saas->text_to_speech( $text, $language );

		if ( is_wp_error( $response ) ) {
			// SaaS returns specific error if subscription/demo quota exceeded.
			$error_message = $response->get_error_message();
			Agentorie_API_Helpers::send_error( $error_message ? $error_message : __( 'Speech synthesis failed.', 'agentorie-chat' ) );
		}

		Agentorie_API_Helpers::send_success( array( 'audio' => isset( $response['audio'] ) ? $response['audio'] : '' ) );
	}

	/**
	 * Handle WebSocket token request.
	 *
	 * This endpoint is used by both:
	 * - Public widget (uses agentorie_public_nonce)
	 * - LiveChat admin (uses agentorie_admin_nonce)
	 *
	 * @return void
	 */
	public function handle_get_ws_token() {
		// Accept either public nonce (widget) or admin nonce (LiveChat).
		$public_nonce_check = Agentorie_API_Helpers::verify_public_nonce();
		$admin_nonce_check  = Agentorie_API_Helpers::verify_nonce( 'agentorie_chat_admin_nonce' );

		if ( true !== $public_nonce_check && ! $admin_nonce_check ) {
			if ( 'expired' === $public_nonce_check ) {
				Agentorie_API_Helpers::send_nonce_expired();
			}
			Agentorie_API_Helpers::send_error( __( 'Security check failed.', 'agentorie-chat' ), 403 );
			return;
		}

		// Per-IP flood protection (anonymous visitors only; admins bypass).
		if ( ! Agentorie_API_Helpers::check_ip_rate_limit( 'global', Agentorie_API_Helpers::RATE_LIMIT_IP_GLOBAL ) ) {
			Agentorie_API_Helpers::send_error( __( 'Too many requests. Please slow down and try again.', 'agentorie-chat' ), 429 );
		}

		$session_id = Agentorie_API_Helpers::get_input( 'session_id', '', 'key' );

		if ( empty( $session_id ) ) {
			Agentorie_API_Helpers::send_error( __( 'Session ID is required.', 'agentorie-chat' ), 400 );
			return;
		}

		// Check settings before making SaaS request.
		$license_status = agentorie_chat_get_setting( 'license_status', 'inactive' );
		$license_key    = agentorie_chat_get_setting( 'license_key', '' );
		$ws_enabled     = agentorie_chat_get_setting( 'websocket_enabled', true );

		if ( 'active' !== $license_status || empty( $license_key ) || ! $ws_enabled ) {
			// Return success with empty token - JS handles this gracefully.
			Agentorie_API_Helpers::send_success( array( 'token' => null ) );
			return;
		}

		$user_type = current_user_can( 'manage_options' ) ? 'admin' : 'visitor';

		// Test mode is decided here, in an uncached AJAX request, rather than
		// read from the page HTML that page caches may serve to every visitor.
		$test_mode = Agentorie_API_Helpers::is_excluded_ip();

		$saas     = Agentorie_API_SaaS::get_instance();
		$response = $saas->make_ws_token_request( $session_id, $user_type, $test_mode );

		if ( is_wp_error( $response ) ) {
			Agentorie_API_Helpers::send_error( $response->get_error_message(), 500 );
			return;
		}

		if ( empty( $response['success'] ) || empty( $response['token'] ) ) {
			Agentorie_API_Helpers::send_error( __( 'Failed to get WebSocket token.', 'agentorie-chat' ), 500 );
			return;
		}

		Agentorie_API_Helpers::send_success(
			array(
				'token'      => $response['token'],
				'ws_url'     => isset( $response['ws_url'] ) ? $response['ws_url'] : 'wss://app.agentorie.com/ws',
				'expires_in' => isset( $response['expires_in'] ) ? $response['expires_in'] : 86400,
				'ui'         => isset( $response['ui'] ) ? $response['ui'] : array(),
			)
		);
	}

	/**
	 * Handle save message request (WebSocket sync).
	 *
	 * This endpoint is used by both:
	 * - Public widget (uses agentorie_public_nonce)
	 * - LiveChat admin (uses agentorie_admin_nonce)
	 *
	 * @return void
	 */
	public function handle_save_message() {
		// Accept either public nonce (widget) or admin nonce (LiveChat).
		$public_nonce_check = Agentorie_API_Helpers::verify_public_nonce();
		$admin_nonce_check  = Agentorie_API_Helpers::verify_nonce( 'agentorie_chat_admin_nonce' );

		if ( true !== $public_nonce_check && ! $admin_nonce_check ) {
			if ( 'expired' === $public_nonce_check ) {
				Agentorie_API_Helpers::send_nonce_expired();
			}
			Agentorie_API_Helpers::send_error( __( 'Security check failed.', 'agentorie-chat' ), 403 );
			return;
		}

		$session_id  = Agentorie_API_Helpers::get_input( 'session_id', '', 'key' );
		$message     = Agentorie_API_Helpers::get_input( 'message', '', 'textarea' );
		$role        = Agentorie_API_Helpers::get_input( 'role', 'user', 'key' );
		$visitor_id  = Agentorie_API_Helpers::get_input( 'visitor_id', '', 'text' );
		$current_url = Agentorie_API_Helpers::get_input( 'current_url', '', 'url' );
		$page_title  = Agentorie_API_Helpers::get_input( 'page_title', '', 'text' );
		$flags       = Agentorie_API_Helpers::get_input( 'flags', array(), 'json' );

		// Per-IP flood protection (anonymous visitors only; admins bypass).
		if ( ! Agentorie_API_Helpers::check_ip_rate_limit( 'global', Agentorie_API_Helpers::RATE_LIMIT_IP_GLOBAL ) ) {
			Agentorie_API_Helpers::send_error( __( 'Too many requests. Please slow down and try again.', 'agentorie-chat' ), 429 );
		}

		// is_admin comes from the widget request, NOT from current_user_can()
		// The widget explicitly sets is_admin=1 only for admin messages from LiveChat
		// Regular bot/user messages from the widget have is_admin=0.
		$is_admin_param = Agentorie_API_Helpers::get_input( 'is_admin', 0, 'absint' );

		// Only trust is_admin=1 if the current user actually has admin rights
		// This prevents visitors from forging is_admin=1.
		$is_admin = ( $is_admin_param && current_user_can( 'manage_options' ) ) ? 1 : 0;
		$admin_id = $is_admin ? get_current_user_id() : 0;

		if ( empty( $session_id ) || ! Agentorie_Session::validate_session_id( $session_id ) ) {
			Agentorie_API_Helpers::send_error( __( 'Invalid session.', 'agentorie-chat' ) );
			return;
		}

		if ( empty( $message ) ) {
			Agentorie_API_Helpers::send_error( __( 'Message is required.', 'agentorie-chat' ) );
			return;
		}

		if ( ! in_array( $role, array( 'user', 'assistant' ), true ) ) {
			$role = 'user';
		}

		$session = Agentorie_Session::get_or_create( $session_id );

		// Update visitor info if provided (for user messages via WebSocket).
		if ( 'user' === $role && ! $is_admin ) {
			if ( ! empty( $visitor_id ) || ! empty( $current_url ) || ! empty( $page_title ) ) {
				$session->update_visitor_info( $visitor_id, $current_url, $page_title );
			}
		}

		$session->save();
		$session->sync_to_database(); // Sync visitor info to DB for LiveChat admin.

		$message_data = array(
			'session_id' => $session_id,
			'role'       => $role,
			'message'    => $message,
			'is_admin'   => $is_admin,
		);

		// Add admin_id only for admin messages.
		if ( $is_admin && $admin_id > 0 ) {
			$message_data['admin_id'] = $admin_id;
		}

		$message_id = Agentorie_Database::insert_message( $message_data );

		if ( ! $message_id ) {
			Agentorie_API_Helpers::send_error( __( 'Failed to save message.', 'agentorie-chat' ), 500 );
			return;
		}

		// Mark session as having admin intervention (permanent flag).
		if ( $is_admin ) {
			Agentorie_Database::update_session_field( $session_id, 'admin_intervened', 1 );
		}

		// Process lead collection flags from WebSocket responses.
		// $flags is already decoded as array by get_input with 'json' type.
		if ( ! empty( $flags ) && 'assistant' === $role ) {
			if ( ! empty( $flags['lead_collected'] ) && ! empty( $flags['lead_data'] ) && is_array( $flags['lead_data'] ) ) {
				$context = array(
					'current_url' => $current_url,
					'page_title'  => $page_title,
				);
				$this->process_lead_collection( $flags['lead_data'], $session_id, $context );
			}
		}

		Agentorie_API_Helpers::send_success( array( 'message_id' => $message_id ) );
	}

	/**
	 * Handle complete onboarding request.
	 *
	 * @return void
	 */
	public function handle_complete_onboarding() {
		$this->verify_nonce_or_fail();

		$saas   = Agentorie_API_SaaS::get_instance();
		$result = $saas->complete_onboarding();

		if ( is_wp_error( $result ) ) {
			Agentorie_API_Helpers::send_error( $result->get_error_message(), 500 );
			return;
		}

		Agentorie_API_SaaS::invalidate_license_cache();

		Agentorie_API_Helpers::send_success(
			array(
				'completed' => true,
				'message'   => __( 'Onboarding completed successfully.', 'agentorie-chat' ),
			)
		);
	}

	/**
	 * Handle translate request.
	 *
	 * Proxies widget UI text translation to SaaS backend.
	 * SaaS uses Gemini + Redis cache for translations.
	 *
	 * @since 1.1.6
	 * @return void
	 */
	public function handle_translate() {
		$this->verify_nonce_or_fail();

		// Per-IP guard on the translation path (each call hits the AI backend).
		if ( ! Agentorie_API_Helpers::check_ip_rate_limit( 'translate', Agentorie_API_Helpers::RATE_LIMIT_IP_TRANSLATE ) ) {
			Agentorie_API_Helpers::send_error( __( 'Too many requests. Please slow down and try again.', 'agentorie-chat' ), 429 );
		}

		$target_lang = Agentorie_API_Helpers::get_input( 'target_lang', '', 'text' );
		$texts       = Agentorie_API_Helpers::get_input( 'texts', array(), 'json' );

		if ( empty( $target_lang ) ) {
			Agentorie_API_Helpers::send_error( __( 'Target language is required.', 'agentorie-chat' ) );
		}

		// Validate BCP-47 format.
		if ( ! preg_match( '/^[a-z]{2,3}(-[A-Z][a-zA-Z]{1,7})?$/i', $target_lang ) ) {
			Agentorie_API_Helpers::send_error( __( 'Invalid language format.', 'agentorie-chat' ) );
		}

		if ( ! is_array( $texts ) || empty( $texts ) ) {
			Agentorie_API_Helpers::send_error( __( 'No texts to translate.', 'agentorie-chat' ) );
		}

		// Sanitize all text values.
		$clean_texts = array();
		foreach ( $texts as $key => $value ) {
			$clean_key   = sanitize_key( $key );
			$clean_value = sanitize_text_field( $value );
			if ( ! empty( $clean_key ) && ! empty( $clean_value ) ) {
				$clean_texts[ $clean_key ] = $clean_value;
			}
		}

		if ( empty( $clean_texts ) ) {
			Agentorie_API_Helpers::send_error( __( 'No valid texts to translate.', 'agentorie-chat' ) );
		}

		$saas     = Agentorie_API_SaaS::get_instance();
		$response = $saas->translate_texts( $target_lang, $clean_texts );

		if ( is_wp_error( $response ) ) {
			$error_message = $response->get_error_message();
			Agentorie_API_Helpers::send_error( $error_message ? $error_message : __( 'Translation failed.', 'agentorie-chat' ) );
		}

		$translations = isset( $response['translations'] ) ? $response['translations'] : array();

		Agentorie_API_Helpers::send_success( array( 'translations' => $translations ) );
	}

	/**
	 * Process lead collection from AI response.
	 *
	 * Accepts lead data from both formats:
	 * - Legacy: ['name', 'email', 'phone', 'request', 'notes']
	 * - New SaaS: ['name', 'email', 'phone', 'message']
	 *
	 * @param array  $lead_data  Lead data.
	 * @param string $session_id Session ID.
	 * @param array  $context    Context data.
	 */
	private function process_lead_collection( $lead_data, $session_id, $context ) {
		$lead_email = agentorie_chat_get_setting( 'lead_collection_email', '' );

		if ( empty( $lead_email ) ) {
			$lead_email = get_option( 'admin_email' );
		}

		$name  = isset( $lead_data['name'] ) ? sanitize_text_field( $lead_data['name'] ) : '';
		$email = isset( $lead_data['email'] ) ? sanitize_email( $lead_data['email'] ) : '';
		$phone = isset( $lead_data['phone'] ) ? sanitize_text_field( $lead_data['phone'] ) : '';
		// Support both 'request' (legacy) and 'message' (new SaaS format).
		$request = isset( $lead_data['request'] ) ? sanitize_text_field( $lead_data['request'] ) : '';
		if ( empty( $request ) && isset( $lead_data['message'] ) ) {
			$request = sanitize_text_field( $lead_data['message'] );
		}
		$notes = isset( $lead_data['notes'] ) ? sanitize_textarea_field( $lead_data['notes'] ) : '';

		$contact_data = array(
			'session_id' => $session_id,
			'name'       => $name,
			'email'      => $email,
			'phone'      => $phone,
			'message'    => $request . ( $notes ? "\n\nNotes: " . $notes : '' ),
		);

		Agentorie_Database::insert_contact( $contact_data );

		$site_name = get_bloginfo( 'name' );
		/* translators: %s: site name */
		$subject = sprintf( __( '[%s] New Lead Collected', 'agentorie-chat' ), $site_name );

		$body = __( "A new lead has been collected by your chatbot.\n\n", 'agentorie-chat' );

		if ( $name ) {
			/* translators: %s: contact name */
			$body .= sprintf( __( "Name: %s\n", 'agentorie-chat' ), $name );
		}
		if ( $email ) {
			/* translators: %s: contact email */
			$body .= sprintf( __( "Email: %s\n", 'agentorie-chat' ), $email );
		}
		if ( $phone ) {
			/* translators: %s: contact phone */
			$body .= sprintf( __( "Phone: %s\n", 'agentorie-chat' ), $phone );
		}
		if ( $request ) {
			/* translators: %s: contact request */
			$body .= sprintf( __( "\nRequest: %s\n", 'agentorie-chat' ), $request );
		}
		if ( $notes ) {
			/* translators: %s: additional notes */
			$body .= sprintf( __( "\nAdditional Notes: %s\n", 'agentorie-chat' ), $notes );
		}

		$body .= "\n---\n";
		/* translators: %s: page URL */
		$body .= sprintf( __( "Page: %s\n", 'agentorie-chat' ), isset( $context['current_url'] ) ? $context['current_url'] : 'N/A' );
		/* translators: %s: session ID */
		$body .= sprintf( __( "Session: %s\n", 'agentorie-chat' ), $session_id );
		/* translators: %s: date and time */
		$body .= sprintf( __( "Date: %s\n", 'agentorie-chat' ), wp_date( 'Y-m-d H:i:s' ) );

		$admin_url = admin_url( 'admin.php?page=agentorie-chat-livechat' );
		/* translators: %s: admin URL to view conversation */
		$body .= sprintf( __( "\nView conversation: %s\n", 'agentorie-chat' ), $admin_url );

		$headers = array( 'Content-Type: text/plain; charset=UTF-8' );

		if ( $email ) {
			$headers[] = 'Reply-To: ' . $name . ' <' . $email . '>';
		}

		wp_mail( $lead_email, $subject, $body, $headers );

		Agentorie_Logger::info(
			'Lead collected',
			array(
				'session_id' => $session_id,
				'name'       => $name,
				'email'      => $email,
				'phone'      => $phone,
				'sent_to'    => $lead_email,
			)
		);
	}
}