<?php
/**
 * SaaS Communication for Agentorie Chat.
 *
 * Handles all communication with the Agentorie SaaS backend.
 *
 * @package    Agentorie_Chat
 * @subpackage Agentorie_Chat/includes
 * @since      1.0.0
 */

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

/**
 * API SaaS class.
 *
 * @since 1.0.0
 */
class Agentorie_API_SaaS {

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

	/**
	 * API URL.
	 *
	 * @var string
	 */
	private $api_url = '';

	/**
	 * License key.
	 *
	 * @var string
	 */
	private $license_key = '';

	/**
	 * Request timeout.
	 *
	 * @var int
	 */
	private $timeout = 30;

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

	/**
	 * Constructor.
	 */
	private function __construct() {
		$this->api_url     = AGENTORIE_CHAT_API_URL;
		$this->license_key = agentorie_chat_get_setting( 'license_key', '' );
	}

	/**
	 * Get language code mapping (short code to full locale).
	 *
	 * @since 1.0.0
	 * @return array Mapping of short language codes to full locale codes.
	 */
	private static function get_lang_map() {
		return array(
			'fr' => 'fr-FR',
			'en' => 'en-US',
			'es' => 'es-ES',
			'de' => 'de-DE',
			'it' => 'it-IT',
			'pt' => 'pt-PT',
			'ru' => 'ru-RU',
			'zh' => 'zh-CN',
			'ja' => 'ja-JP',
			'ar' => 'ar-SA',
		);
	}

	/**
	 * Send message to SaaS.
	 *
	 * @param string $session_id        Session ID.
	 * @param string $message           Message content.
	 * @param array  $context           Context data.
	 * @param bool   $exclude_from_stats Exclude from stats.
	 * @return array|WP_Error Response or error.
	 */
	public function send_message( $session_id, $message, $context = array(), $exclude_from_stats = false ) {
		$endpoint = $this->api_url . '/chat';
		$body     = array(
			'session_id'         => $session_id,
			'message'            => $message,
			'exclude_from_stats' => $exclude_from_stats,
			'site_url'           => home_url(),
			'context'            => array_merge(
				array(
					'visitor_id'  => isset( $context['visitor_id'] ) ? $context['visitor_id'] : '',
					'current_url' => isset( $context['current_url'] ) ? $context['current_url'] : '',
					'page_title'  => isset( $context['page_title'] ) ? $context['page_title'] : '',
					'referrer'    => isset( $context['referrer'] ) ? $context['referrer'] : '',
					'user_agent'  => isset( $context['user_agent'] ) ? $context['user_agent'] : '',
					'ip_address'  => Agentorie_Session::get_client_ip(),
					'language'    => isset( $context['language'] ) ? $context['language'] : get_locale(),
				),
				$context
			),
		);
		return $this->make_request( 'POST', $endpoint, $body );
	}

	/**
	 * Sync config with SaaS.
	 *
	 * @param array $config Configuration data.
	 * @return array|WP_Error Response or error.
	 */
	public function sync_config( $config = array() ) {
		$endpoint = $this->api_url . '/license/config';
		$body     = array_merge(
			array( 'site_url' => home_url() ),
			$config
		);
		return $this->make_request( 'POST', $endpoint, $body );
	}

	/**
	 * Complete onboarding.
	 *
	 * @return array|WP_Error Response or error.
	 */
	public function complete_onboarding() {
		$endpoint = $this->api_url . '/onboarding/complete';
		return $this->make_request( 'POST', $endpoint, array() );
	}

	/**
	 * Notify SaaS that indexed content has been updated.
	 *
	 * This triggers cache-busting by incrementing the content_version
	 * on the SaaS side. The next chat request will use a different
	 * query parameter, bypassing any cached responses.
	 *
	 * @since 1.0.0
	 * @return array|WP_Error Response or error.
	 */
	public function notify_content_updated() {
		$endpoint = $this->api_url . '/content/updated';
		$body     = array(
			'event'     => 'content.updated',
			'timestamp' => time(),
		);
		return $this->make_request( 'POST', $endpoint, $body );
	}

	/**
	 * Check license status.
	 *
	 * @param string $license_key   License key.
	 * @param bool   $force_refresh Force refresh.
	 * @return array|WP_Error Response or error.
	 */
	public static function check_license( $license_key, $force_refresh = false ) {
		$instance = self::get_instance();

		if ( ! $force_refresh ) {
			$cached = get_transient( 'agentorie_chat_license_cache' );
			if ( false !== $cached ) {
				return $cached;
			}
		}

		$endpoint = $instance->api_url . '/license/status';
		$body     = array(
			'license_key' => $license_key,
			'site_url'    => home_url(),
		);
		$response = $instance->make_request( 'POST', $endpoint, $body );

		if ( ! is_wp_error( $response ) ) {
			set_transient( 'agentorie_chat_license_cache', $response, 6 * HOUR_IN_SECONDS );
			self::process_license_response( $response );
		}

		return $response;
	}

	/**
	 * Process license response and update settings.
	 *
	 * @param array $response License response data.
	 */
	private static function process_license_response( $response ) {
		if ( ! isset( $response['status'] ) ) {
			return;
		}

		$status = ( 'active' === $response['status'] ) ? 'active' : 'inactive';
		agentorie_chat_update_setting( 'license_status', $status );

		if ( isset( $response['features'] ) && is_array( $response['features'] ) ) {
			agentorie_chat_update_setting( 'license_features', $response['features'] );
		}

		if ( isset( $response['active_languages'] ) && is_array( $response['active_languages'] ) ) {
			agentorie_chat_update_setting( 'active_languages', array_map( 'sanitize_text_field', $response['active_languages'] ) );
		}

		if ( isset( $response['rate_limit'] ) ) {
			agentorie_chat_update_setting( 'rate_limit', (int) $response['rate_limit'] );
		}

		if ( isset( $response['demos'] ) && is_array( $response['demos'] ) ) {
			$demos = $response['demos'];
			agentorie_chat_update_setting( 'demo_voice_active', isset( $demos['voice_active'] ) ? (bool) $demos['voice_active'] : false );
			agentorie_chat_update_setting( 'demo_voice_remaining', isset( $demos['voice_remaining'] ) ? (int) $demos['voice_remaining'] : 0 );
			agentorie_chat_update_setting( 'demo_lang_remaining', isset( $demos['lang_remaining'] ) ? (int) $demos['lang_remaining'] : 0 );
			agentorie_chat_update_setting( 'demo_lang_active', isset( $demos['lang_active'] ) ? sanitize_text_field( $demos['lang_active'] ) : '' );
		}

		if ( isset( $response['usage'] ) && is_array( $response['usage'] ) ) {
			if ( isset( $response['usage']['test_conversations'] ) ) {
				agentorie_chat_update_setting( 'test_conversations_count', (int) $response['usage']['test_conversations'] );
			}
		}

		if ( isset( $response['config']['lead_collection_instructions'] ) ) {
			agentorie_chat_update_setting( 'lead_collection_instructions', sanitize_textarea_field( $response['config']['lead_collection_instructions'] ) );
		}

		if ( isset( $response['config']['lead_collection_email'] ) ) {
			agentorie_chat_update_setting( 'lead_collection_email', sanitize_email( $response['config']['lead_collection_email'] ) );
		}

		if ( isset( $response['config']['voice_enabled'] ) ) {
			agentorie_chat_update_setting( 'voice_enabled', (bool) $response['config']['voice_enabled'] );
		}

		if ( isset( $response['config']['content_indexing_limit'] ) ) {
			agentorie_chat_update_setting( 'content_indexing_limit', (int) $response['config']['content_indexing_limit'] );
		}

		if ( isset( $response['config']['woo_indexing_limit'] ) ) {
			agentorie_chat_update_setting( 'woo_indexing_limit', (int) $response['config']['woo_indexing_limit'] );
		}

		if ( isset( $response['config']['language'] ) ) {
			// SaaS now stores BCP-47 directly (fr-FR, en-US, etc.).
			$saas_lang = sanitize_text_field( $response['config']['language'] );
			// Only set language from SaaS on initial activation (when no local value exists yet).
			if ( ! agentorie_chat_get_setting( 'default_language' ) ) {
				agentorie_chat_update_setting( 'default_language', $saas_lang );
			}
		}

		if ( 'active' !== $status ) {
			agentorie_chat_update_setting( 'enabled', false );
		}
	}

	/**
	 * Invalidate license cache.
	 */
	public static function invalidate_license_cache() {
		delete_transient( 'agentorie_chat_license_cache' );
	}

	/**
	 * Activate license.
	 *
	 * @param string $license_key License key.
	 * @return array|WP_Error Response or error.
	 */
	public static function activate_license( $license_key ) {
		$instance = self::get_instance();
		$endpoint = $instance->api_url . '/license/activate';
		$body     = array(
			'license_key'    => $license_key,
			'domain'         => wp_parse_url( home_url(), PHP_URL_HOST ),
			'site_url'       => home_url(),
			'site_name'      => get_bloginfo( 'name' ),
			'admin_email'    => get_option( 'admin_email' ),
			'wp_version'     => get_bloginfo( 'version' ),
			'php_version'    => PHP_VERSION,
			'plugin_version' => AGENTORIE_CHAT_VERSION,
		);

		$response = $instance->make_request( 'POST', $endpoint, $body, false );

		if ( ! is_wp_error( $response ) && ! empty( $response['success'] ) ) {
			$instance->license_key = $license_key;
			delete_transient( 'agentorie_chat_license_cache' );
		}

		return $response;
	}

	/**
	 * Deactivate license.
	 *
	 * @param string $license_key License key.
	 * @return array|WP_Error Response or error.
	 */
	public static function deactivate_license( $license_key = '' ) {
		$instance = self::get_instance();
		$endpoint = $instance->api_url . '/license/deactivate';
		$body     = array(
			'license_key' => $license_key ? $license_key : $instance->license_key,
			'domain'      => wp_parse_url( home_url(), PHP_URL_HOST ),
			'site_url'    => home_url(),
		);
		return $instance->make_request( 'POST', $endpoint, $body );
	}

	/**
	 * Send admin message (stub for future WebSocket integration).
	 *
	 * @param string $session_id Session ID.
	 * @param string $message    Message content.
	 * @param int    $admin_id   Admin user ID.
	 * @return array Empty array (handled via WebSocket).
	 */
	public function send_admin_message( $session_id, $message, $admin_id ) { // phpcs:ignore Generic.CodeAnalysis.UnusedFunctionParameter.FoundAfterLastUsed -- Stub method, parameters required by interface.
		return array();
	}

	/**
	 * Takeover conversation (stub for future WebSocket integration).
	 *
	 * @param string $session_id Session ID.
	 * @param int    $admin_id   Admin user ID.
	 * @return array Empty array (handled via WebSocket).
	 */
	public function takeover_conversation( $session_id, $admin_id ) { // phpcs:ignore Generic.CodeAnalysis.UnusedFunctionParameter.FoundAfterLastUsed -- Stub method, parameters required by interface.
		return array();
	}

	/**
	 * Release conversation (stub for future WebSocket integration).
	 *
	 * @param string $session_id Session ID.
	 * @param int    $admin_id   Admin user ID.
	 * @return array Empty array (handled via WebSocket).
	 */
	public function release_conversation( $session_id, $admin_id ) { // phpcs:ignore Generic.CodeAnalysis.UnusedFunctionParameter.FoundAfterLastUsed -- Stub method, parameters required by interface.
		return array();
	}

	/**
	 * Updates the presence status of an admin on livechat.
	 *
	 * @param int    $admin_id   WordPress user ID.
	 * @param string $admin_name Display name.
	 * @param bool   $online     Online status.
	 * @return array|WP_Error Response array or WP_Error on failure.
	 */
	public function update_presence( int $admin_id, string $admin_name, bool $online ) {
		$endpoint = $this->api_url . '/livechat/presence';
		$body     = array(
			'admin_id'   => (string) $admin_id,
			'admin_name' => $admin_name,
			'online'     => $online,
		);

		$response = $this->make_request( 'POST', $endpoint, $body );

		// If WP_Error (e.g. 403), extract data from body.
		if ( is_wp_error( $response ) ) {
			$error_data = $response->get_error_data();

			// Data is in error_data['body'] (see make_request).
			if ( isset( $error_data['body'] ) && is_array( $error_data['body'] ) ) {
				$body_data  = $error_data['body'];
				$error_code = isset( $body_data['error_code'] ) ? $body_data['error_code'] : null;

				// If it's a limit error, create WP_Error with proper data.
				if ( 'admin_limit_reached' === $error_code ) {
					return new WP_Error(
						'agentorie_chat_admin_limit_reached',
						isset( $body_data['error'] ) ? $body_data['error'] : 'Admin seat limit reached',
						array(
							'error_code'   => 'admin_limit_reached',
							'online_count' => isset( $body_data['online_count'] ) ? $body_data['online_count'] : 0,
							'max_admins'   => isset( $body_data['max_admins'] ) ? $body_data['max_admins'] : 1,
						)
					);
				}
			}

			return $response;
		}

		// Check if it's a limit error in response (success=false case).
		if ( isset( $response['success'] ) && false === $response['success'] ) {
			return new WP_Error(
				isset( $response['error_code'] ) ? $response['error_code'] : 'agentorie_chat_presence_error',
				isset( $response['error'] ) ? $response['error'] : 'Unknown error',
				array(
					'error_code'   => isset( $response['error_code'] ) ? $response['error_code'] : null,
					'online_count' => isset( $response['online_count'] ) ? $response['online_count'] : 0,
					'max_admins'   => isset( $response['max_admins'] ) ? $response['max_admins'] : 1,
				)
			);
		}

		return $response;
	}

	/**
	 * Speech to text.
	 *
	 * @param string $audio_data Base64 audio data.
	 * @param string $language   Language code.
	 * @return array|WP_Error Response or error.
	 */
	public function speech_to_text( $audio_data, $language = 'fr-FR' ) {
		$endpoint = $this->api_url . '/voice/stt';
		$body     = array(
			'audio'    => $audio_data,
			'language' => $language,
			'site_url' => home_url(),
		);
		return $this->make_request( 'POST', $endpoint, $body );
	}

	/**
	 * Text to speech.
	 *
	 * @param string $text     Text content.
	 * @param string $language Language code.
	 * @return array|WP_Error Response or error.
	 */
	public function text_to_speech( $text, $language = 'fr-FR' ) {
		$endpoint = $this->api_url . '/voice/tts';
		$body     = array(
			'text'     => $text,
			'language' => $language,
			'site_url' => home_url(),
		);
		return $this->make_request( 'POST', $endpoint, $body );
	}

	/**
	 * Translate widget UI texts via SaaS (Gemini + Redis cache).
	 *
	 * @since 1.1.6
	 * @param string $target_lang BCP-47 language code.
	 * @param array  $texts       Key-value pairs of texts to translate.
	 * @return array|WP_Error Response with translations or error.
	 */
	public function translate_texts( $target_lang, $texts ) {
		$endpoint = $this->api_url . '/translate';
		$body     = array(
			'target_lang' => $target_lang,
			'texts'       => $texts,
		);
		return $this->make_request( 'POST', $endpoint, $body );
	}

	/**
	 * Check if API is reachable.
	 *
	 * @return bool True if reachable.
	 */
	public function is_api_reachable() {
		$response = wp_remote_get(
			$this->api_url . '/health',
			array(
				'timeout'   => 5,
				'sslverify' => true,
			)
		);
		if ( is_wp_error( $response ) ) {
			return false;
		}
		$code = wp_remote_retrieve_response_code( $response );
		return $code >= 200 && $code < 300;
	}

	/**
	 * Request WebSocket token from SaaS.
	 *
	 * @param string $session_id Session ID.
	 * @param string $user_type  User type (visitor or admin).
	 * @param bool   $test_mode  Whether the visitor is in test mode (excluded from stats).
	 * @return array|WP_Error Response or error.
	 */
	public function make_ws_token_request( $session_id, $user_type = 'visitor', $test_mode = false ) {
		$endpoint = $this->api_url . '/ws/token';
		$body     = array(
			'session_id' => $session_id,
			'user_type'  => $user_type,
			'test_mode'  => (bool) $test_mode,
		);
		return $this->make_request( 'POST', $endpoint, $body );
	}

	/**
	 * Handle search content REST endpoint.
	 *
	 * @param WP_REST_Request $request The request object.
	 * @return WP_REST_Response Response.
	 */
	public function handle_search_content( $request ) {
		$query = sanitize_text_field( $request->get_param( 'query' ) );
		$limit = absint( $request->get_param( 'limit' ) );

		if ( empty( $query ) ) {
			return new WP_REST_Response(
				array(
					'success' => false,
					'error'   => 'Query parameter is required',
				),
				400
			);
		}

		if ( $limit < 1 || $limit > 20 ) {
			$limit = 5;
		}

		if ( ! class_exists( 'Agentorie_Content_Indexer' ) ) {
			return new WP_REST_Response(
				array(
					'success' => false,
					'error'   => 'Content Indexer not available',
				),
				500
			);
		}

		$indexer = Agentorie_Content_Indexer::get_instance();
		$results = $indexer->search( $query, $limit );

		return new WP_REST_Response(
			array(
				'success' => true,
				'results' => $results,
				'query'   => $query,
			),
			200
		);
	}

	/**
	 * Handle get indexed content REST endpoint.
	 *
	 * Returns indexed content for direct AI injection. Supports an optional
	 * limit parameter to restrict the number of results, allowing the SaaS
	 * to enforce plan-based quotas.
	 *
	 * @since 1.0.0
	 * @param WP_REST_Request $request The request object.
	 * @return WP_REST_Response Response with indexed content.
	 */
	public function handle_get_indexed_content( $request ) {
		if ( ! class_exists( 'Agentorie_Content_Indexer' ) ) {
			return new WP_REST_Response(
				array(
					'success' => false,
					'error'   => 'Content Indexer not available',
				),
				500
			);
		}

		$indexer = Agentorie_Content_Indexer::get_instance();

		// Get optional limit parameter from SaaS (plan-based quota).
		$limit = $request->get_param( 'limit' );
		$limit = ( null !== $limit ) ? absint( $limit ) : null;

		// Get results with optional limit.
		$results = $indexer->get_all_indexed( $limit );

		// Get total count for UI display (shows "X indexed, Y used by AI").
		$total_indexed = $indexer->get_total_count();

		return new WP_REST_Response(
			array(
				'success'       => true,
				'results'       => $results,
				'count'         => count( $results ),
				'total_indexed' => $total_indexed,
			),
			200
		);
	}

	/**
	 * Handle get indexed products REST endpoint.
	 *
	 * Returns WooCommerce products with pre-stored enriched data (price, stock,
	 * categories, attributes) from the index. Returns empty results if no
	 * products are indexed.
	 *
	 * @since 1.2.0
	 * @param WP_REST_Request $request The request object.
	 * @return WP_REST_Response Response with indexed products.
	 */
	public function handle_get_indexed_products( $request ) {
		if ( ! class_exists( 'Agentorie_Content_Indexer' ) ) {
			return new WP_REST_Response(
				array(
					'success' => false,
					'error'   => 'Content Indexer not available',
				),
				500
			);
		}

		$indexer = Agentorie_Content_Indexer::get_instance();

		// Get optional limit parameter from SaaS (plan-based quota).
		$limit = $request->get_param( 'limit' );
		$limit = ( null !== $limit ) ? absint( $limit ) : null;

		$results       = $indexer->get_all_indexed_products( $limit );
		$product_stats = $indexer->get_product_stats();

		return new WP_REST_Response(
			array(
				'success'       => true,
				'results'       => $results,
				'count'         => count( $results ),
				'total_indexed' => $product_stats['total_indexed'],
			),
			200
		);
	}

	/**
	 * Make HTTP request to SaaS API.
	 *
	 * @param string $method       HTTP method.
	 * @param string $endpoint     API endpoint URL.
	 * @param array  $body         Request body.
	 * @param bool   $include_auth Include authentication headers.
	 * @return array|WP_Error Response data or error.
	 */
	private function make_request( $method, $endpoint, $body = array(), $include_auth = true ) {
		$headers = array(
			'Content-Type' => 'application/json',
			'Accept'       => 'application/json',
			'User-Agent'   => 'Agentorie-Chat-Plugin/' . AGENTORIE_CHAT_VERSION,
		);

		if ( $include_auth ) {
			$license_key = isset( $body['license_key'] ) ? $body['license_key'] : $this->license_key;
			if ( ! empty( $license_key ) ) {
				$headers['X-License-Key'] = $license_key;
			}
			$headers['X-Domain'] = wp_parse_url( home_url(), PHP_URL_HOST );
		}

		$args = array(
			'method'    => $method,
			'headers'   => $headers,
			'timeout'   => $this->timeout,
			'sslverify' => true,
		);

		if ( ! empty( $body ) && in_array( $method, array( 'POST', 'PUT', 'PATCH' ), true ) ) {
			$args['body'] = wp_json_encode( $body );
		}

		$response = wp_remote_request( $endpoint, $args );

		if ( is_wp_error( $response ) ) {
			Agentorie_Logger::error(
				'API request failed',
				array(
					'endpoint' => $endpoint,
					'error'    => $response->get_error_message(),
				)
			);
			return $response;
		}

		$response_code = wp_remote_retrieve_response_code( $response );
		$response_body = wp_remote_retrieve_body( $response );
		$data          = json_decode( $response_body, true );

		if ( $response_code >= 400 ) {
			$error_message = isset( $data['error'] ) ? $data['error'] : ( isset( $data['message'] ) ? $data['message'] : 'Unknown API error' );
			Agentorie_Logger::error(
				'API error response',
				array(
					'endpoint' => $endpoint,
					'code'     => $response_code,
					'message'  => $error_message,
				)
			);
			return new WP_Error(
				'agentorie_chat_api_error',
				$error_message,
				array(
					'status' => $response_code,
					'body'   => $data,
				)
			);
		}

		if ( null === $data && ! empty( $response_body ) ) {
			Agentorie_Logger::warning( 'Invalid JSON response from API', array( 'endpoint' => $endpoint ) );
			return new WP_Error( 'agentorie_chat_json_error', __( 'Invalid response from API', 'agentorie-chat' ) );
		}

		return $data ? $data : array();
	}
}