<?php
/**
 * Stable public integration contract for themes and companion plugins.
 *
 * Consumers should use aimogen_integration() and must not read Aimogen options,
 * database tables, or internal classes directly.
 *
 * @package Aimogen
 */

defined( 'ABSPATH' ) || exit;

if ( ! class_exists( 'Aimogen_Integration_API' ) ) {
	final class Aimogen_Integration_API {
		const API_VERSION = '1.1.0';

		/** @var self|null */
		private static $instance = null;

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

			return self::$instance;
		}

		/** @return string */
		public function get_api_version() {
			return self::API_VERSION;
		}

		/** @param string $minimum_version Required API version. @return bool */
		public function is_compatible( $minimum_version = '1.0.0' ) {
			return version_compare( self::API_VERSION, (string) $minimum_version, '>=' );
		}

		/** @return array<string,mixed> */
		public function get_status() {
			$status = array(
				'available'           => shortcode_exists( 'aimogen-chat-form' ),
				'api_version'         => self::API_VERSION,
				'edition'             => defined( 'AIMOGEN_IS_PRO' ) ? 'pro' : 'free',
				'plugin_version'      => function_exists( 'aimogen_get_version' ) ? aimogen_get_version() : '',
				'pro_plugin_version'  => function_exists( 'aimogenpro_get_version' ) ? aimogenpro_get_version() : '',
			);

			return apply_filters( 'aimogen_integration_status', $status, $this );
		}

		/** @return array<string,bool> */
		public function get_capabilities() {
			$capabilities = array(
				'chat'                => shortcode_exists( 'aimogen-chat-form' ),
				'chatbots'            => true,
				'text'                => false,
				'images'              => false,
				'embeddings'          => false,
				'knowledge_bases'     => false,
				'streaming'           => true,
				'voice'               => false,
				'persistent_chat'     => false,
				'lead_capture'        => false,
				'workflows'           => false,
				'agents'              => false,
				'automation'          => false,
				'provider_management' => false,
				'usage_controls'      => false,
			);

			$capabilities = apply_filters( 'aimogen_integration_capabilities', $capabilities, $this );
			$normalized   = array();

			foreach ( (array) $capabilities as $capability => $supported ) {
				$key = sanitize_key( $capability );
				if ( '' !== $key ) {
					$normalized[ $key ] = (bool) $supported;
				}
			}

			return $normalized;
		}

		/** @param string $capability Capability name. @return bool */
		public function supports( $capability ) {
			$capabilities = $this->get_capabilities();
			$capability   = sanitize_key( $capability );

			return ! empty( $capabilities[ $capability ] );
		}

		/**
		 * Return normalized chatbots available to the active Aimogen renderer.
		 *
		 * @return array<int,array<string,mixed>>
		 */
		public function get_chatbots() {
			$chatbots = array(
				array(
					'id'          => 'default',
					'title'       => __( 'Aimogen Chatbot', 'aimogen' ),
					'description' => __( 'Uses the chatbot configured in Aimogen.', 'aimogen' ),
					'avatar'      => '',
					'source'      => 'aimogen-free',
				),
			);

			$chatbots = apply_filters( 'aimogen_integration_chatbots', $chatbots, $this );

			return $this->normalize_resources( $chatbots, false );
		}

		/**
		 * Backward-compatible alias for early integration consumers.
		 *
		 * @deprecated 1.1.0 Use get_chatbots().
		 * @return array<int,array<string,mixed>>
		 */
		public function get_assistants() {
			return $this->get_chatbots();
		}

		/**
		 * Extensible resource discovery for future approved integrations.
		 *
		 * Supported resource types are intentionally filter-driven. Aimogen Pro can
		 * expose knowledge bases or workflows without changing the public contract.
		 *
		 * @param string $type Resource type.
		 * @return array<int,array<string,mixed>>
		 */
		public function get_resources( $type ) {
			$type      = sanitize_key( $type );
			$resources = apply_filters( 'aimogen_integration_resources_' . $type, array(), $this );

			return $this->normalize_resources( $resources, false );
		}

		/**
		 * Render an approved chatbot instance through Aimogen's registered shortcode.
		 *
		 * @param string $chatbot_id Chatbot ID.
		 * @param array  $args       Approved presentation and feature arguments.
		 * @return string|WP_Error
		 */
		public function render_chatbot( $chatbot_id = 'default', $args = array() ) {
			if ( ! $this->supports( 'chat' ) || ! shortcode_exists( 'aimogen-chat-form' ) ) {
				return new WP_Error( 'aimogen_chat_unavailable', __( 'Aimogen chat is not available.', 'aimogen' ) );
			}

			$chatbot_id = sanitize_key( (string) $chatbot_id );
			$chatbot_id = '' === $chatbot_id ? 'default' : $chatbot_id;
			$valid_ids  = wp_list_pluck( $this->get_chatbots(), 'id' );

			if ( ! in_array( $chatbot_id, $valid_ids, true ) ) {
				return new WP_Error( 'aimogen_invalid_chatbot', __( 'The selected Aimogen chatbot is not available.', 'aimogen' ) );
			}

			$approved = $this->sanitize_chatbot_args( (array) $args );

			global $shortcode_tags;
			$callback = isset( $shortcode_tags['aimogen-chat-form'] ) ? $shortcode_tags['aimogen-chat-form'] : null;
			if ( ! is_callable( $callback ) ) {
				return new WP_Error( 'aimogen_chat_unavailable', __( 'Aimogen chat is not available.', 'aimogen' ) );
			}

			$buffer_level = ob_get_level();
			try {
				ob_start();
				$result   = call_user_func( $callback, $approved, null, 'aimogen-chat-form' );
				$captured = ob_get_clean();
			} catch ( Throwable $error ) {
				while ( ob_get_level() > $buffer_level ) {
					ob_end_clean();
				}
				return new WP_Error( 'aimogen_chat_render_failed', __( 'Aimogen could not render this chatbot.', 'aimogen' ) );
			}

			return (string) $captured . ( is_string( $result ) ? $result : '' );
		}

		/** @param string $area Admin destination. @return string */
		public function get_admin_url( $area = 'chatbot' ) {
			$chatbot_url = admin_url( 'admin.php?page=aimogen_chatbot_panel' );
			$urls = array(
				'chatbot'    => $chatbot_url,
				'assistants' => $chatbot_url,
				'settings'   => admin_url( 'admin.php?page=aimogen_admin_settings' ),
			);

			$urls = apply_filters( 'aimogen_integration_admin_urls', $urls, $this );
			$area = sanitize_key( $area );

			return isset( $urls[ $area ] ) ? esc_url_raw( $urls[ $area ] ) : '';
		}

		/** @param array<string,mixed> $args Raw arguments. @return array<string,string> */
		private function sanitize_chatbot_args( $args ) {
			$output = array();
			$text_limits = array(
				'ai_first_message' => 600,
				'placeholder'      => 180,
				'submit'           => 80,
				'ai_name'          => 120,
				'ai_role'          => 120,
			);

			foreach ( $text_limits as $key => $limit ) {
				if ( isset( $args[ $key ] ) ) {
					$output[ $key ] = $this->limit( sanitize_text_field( $args[ $key ] ), $limit );
				}
			}

			foreach ( array( 'ai_avatar', 'user_avatar' ) as $key ) {
				if ( ! empty( $args[ $key ] ) ) {
					$output[ $key ] = esc_url_raw( $args[ $key ] );
				}
			}

			$enums = array(
				'show_in_window'       => array( 'on', 'off' ),
				'window_location'      => array( 'bottom-right', 'bottom-left', 'top-right', 'top-left' ),
				'show_header'          => array( 'show', 'hide' ),
				'show_ai_avatar'       => array( 'show', 'hide' ),
				'show_user_avatar'     => array( 'show', 'hide' ),
				'bubble_alignment'     => array( 'left', 'center', 'right' ),
				'bubble_user_alignment'=> array( 'left', 'center', 'right' ),
			);

			foreach ( $enums as $key => $allowed ) {
				if ( isset( $args[ $key ] ) && in_array( (string) $args[ $key ], $allowed, true ) ) {
					$output[ $key ] = (string) $args[ $key ];
				}
			}

			foreach ( array( 'background', 'general_background', 'user_font_color', 'user_background_color', 'ai_font_color', 'ai_background_color', 'input_text_color', 'input_placeholder_color', 'input_border_color', 'submit_color', 'submit_text_color' ) as $key ) {
				if ( isset( $args[ $key ] ) ) {
					$color = sanitize_hex_color( $args[ $key ] );
					if ( $color ) {
						$output[ $key ] = $color;
					}
				}
			}

			foreach ( array( 'font_size', 'height', 'minheight', 'width', 'bubble_width' ) as $key ) {
				if ( isset( $args[ $key ] ) && preg_match( '/^(?:\d+(?:\.\d+)?)(?:px|%|em|rem|vh|vw)$/', (string) $args[ $key ] ) ) {
					$output[ $key ] = (string) $args[ $key ];
				}
			}

			if ( $this->supports( 'persistent_chat' ) && isset( $args['persistent'] ) && in_array( $args['persistent'], array( 'off', 'on', 'history', 'logs' ), true ) ) {
				$output['persistent'] = $args['persistent'];
			}

			if ( $this->supports( 'embeddings' ) ) {
				if ( isset( $args['embeddings'] ) && in_array( $args['embeddings'], array( 'enabled', 'disabled' ), true ) ) {
					$output['embeddings'] = $args['embeddings'];
				}
				if ( ! empty( $args['embeddings_namespace'] ) ) {
					$output['embeddings_namespace'] = $this->limit( sanitize_text_field( $args['embeddings_namespace'] ), 190 );
				}
			}

			if ( $this->supports( 'lead_capture' ) && isset( $args['store_data'] ) && in_array( $args['store_data'], array( 'on', 'off' ), true ) ) {
				$output['store_data'] = $args['store_data'];
			}

			if ( $this->supports( 'voice' ) && isset( $args['chatbot_text_speech'] ) && in_array( $args['chatbot_text_speech'], array( '', 'off', 'free' ), true ) ) {
				$output['chatbot_text_speech'] = $args['chatbot_text_speech'];
			}

			return apply_filters( 'aimogen_integration_chatbot_args', $output, $args, $this );
		}

		/** @param array<int,mixed> $resources Resources. @param bool $allow_default Whether an empty ID is valid. @return array<int,array<string,mixed>> */
		private function normalize_resources( $resources, $allow_default ) {
			$output = array();
			$seen   = array();

			foreach ( (array) $resources as $resource ) {
				if ( ! is_array( $resource ) || ! array_key_exists( 'id', $resource ) || empty( $resource['title'] ) ) {
					continue;
				}

				$id = sanitize_text_field( (string) $resource['id'] );
				if ( '' === $id && ! $allow_default ) {
					continue;
				}
				if ( isset( $seen[ $id ] ) ) {
					continue;
				}

				$seen[ $id ] = true;
				$output[]    = array(
					'id'          => $id,
					'title'       => sanitize_text_field( $resource['title'] ),
					'description' => isset( $resource['description'] ) ? sanitize_text_field( $resource['description'] ) : '',
					'avatar'      => isset( $resource['avatar'] ) ? esc_url_raw( $resource['avatar'] ) : '',
					'source'      => isset( $resource['source'] ) ? sanitize_key( $resource['source'] ) : 'aimogen',
				);
			}

			return $output;
		}

		/** @param string $value Value. @param int $maximum Maximum length. @return string */
		private function limit( $value, $maximum ) {
			return function_exists( 'mb_substr' ) ? mb_substr( (string) $value, 0, $maximum ) : substr( (string) $value, 0, $maximum );
		}
	}
}

if ( ! function_exists( 'aimogen_integration' ) ) {
	/** @return Aimogen_Integration_API */
	function aimogen_integration() {
		return Aimogen_Integration_API::instance();
	}
}

add_action(
	'plugins_loaded',
	static function () {
		do_action( 'aimogen_integration_ready', aimogen_integration() );
	},
	25
);