<?php
namespace AdvancedAddons\Tools;

use AdvancedAddons\Connector_Settings;
use AdvancedAddons\Tool;

/**
 * Search Unsplash for images.
 */
class Search_Unsplash_Image_Tool implements Tool {
	const DOWNLOAD_MAP_TRANSIENT_PREFIX = 'advanced_addons_unsplash_dl_';

	public function name(): string {
		return 'search_unsplash_image';
	}

	public function description(): string {
		return 'Search Unsplash for high-quality stock images. Returns image URLs and attribution info. ' .
			'Call this before generating a section that needs images (hero backgrounds, cards, galleries, feature images) ' .
			'and use the returned "url" values directly in the generated HTML <img> src or CSS background-image. ' .
			'Always include photographer credit (name + Unsplash profile link) near the image when displayed. ' .
			'Requires an Unsplash API key configured in Settings > Connectors.';
	}

	public function input_schema(): array {
		return array(
			'type'       => 'object',
			'properties' => array(
				'query' => array(
					'type'        => 'string',
					'description' => 'Search keywords describing the image, e.g. "mountain landscape sunset".',
				),
				'per_page' => array(
					'type'        => 'integer',
					'minimum'     => 1,
					'maximum'     => 20,
					'default'     => 5,
					'description' => 'Number of results to return (max 20).',
				),
				'orientation' => array(
					'type'        => 'string',
					'enum'        => array( 'landscape', 'portrait', 'squarish' ),
					'description' => 'Optional. Preferred orientation of the images.',
				),
			),
			'required' => array( 'query' ),
		);
	}

	public function execute( array $input, array $context = array() ): array {
		$api_key = Connector_Settings::get_unsplash_api_key();

		if ( empty( $api_key ) ) {
			return array(
				'type'    => 'error',
				'message' => __( 'Unsplash API key is not configured. Please add it in Settings > Connectors.', 'advanced-animation' ),
			);
		}

		$query    = sanitize_text_field( (string) ( $input['query'] ?? '' ) );
		$per_page = min( max( intval( $input['per_page'] ?? 5 ), 1 ), 20 );

		if ( empty( $query ) ) {
			return array(
				'type'    => 'error',
				'message' => __( 'No search query provided.', 'advanced-animation' ),
			);
		}

		$args = array(
			'query'     => $query,
			'per_page'  => $per_page,
			'client_id' => $api_key,
		);

		$orientation = sanitize_key( (string) ( $input['orientation'] ?? '' ) );
		if ( in_array( $orientation, array( 'landscape', 'portrait', 'squarish' ), true ) ) {
			$args['orientation'] = $orientation;
		}

		$url = add_query_arg( $args, 'https://api.unsplash.com/search/photos' );

		$response = wp_remote_get(
			$url,
			array(
				'timeout' => 15,
				'headers' => array(
					'Accept-Version' => 'v1',
				),
			)
		);

		if ( is_wp_error( $response ) ) {
			return array(
				'type'    => 'error',
				'message' => $response->get_error_message(),
			);
		}

		$code = wp_remote_retrieve_response_code( $response );
		$body = wp_remote_retrieve_body( $response );
		$data = json_decode( $body, true );

		if ( 200 !== intval( $code ) ) {
			$message = __( 'Unsplash request failed.', 'advanced-animation' );
			if ( is_array( $data ) && ! empty( $data['errors'] ) ) {
				$first_error = is_array( $data['errors'][0] ) ? ( $data['errors'][0]['detail'] ?? '' ) : (string) $data['errors'][0];
				if ( $first_error ) {
					$message = sanitize_text_field( $first_error );
				}
			}
			return array(
				'type'    => 'error',
				'message' => $message,
			);
		}

		if ( ! is_array( $data ) || ! isset( $data['results'] ) || ! is_array( $data['results'] ) ) {
			return array(
				'type'    => 'error',
				'message' => __( 'Unsplash returned an unexpected response.', 'advanced-animation' ),
			);
		}

		$images = array();
		foreach ( $data['results'] as $result ) {
			if ( ! is_array( $result ) ) {
				continue;
			}

			$user         = is_array( $result['user'] ?? null ) ? $result['user'] : array();
			$urls         = is_array( $result['urls'] ?? null ) ? $result['urls'] : array();
			$links        = is_array( $result['links'] ?? null ) ? $result['links'] : array();
			$user_links   = is_array( $user['links'] ?? null ) ? $user['links'] : array();
			$photographer = sanitize_text_field( (string) ( $user['name'] ?? '' ) );
			$username     = sanitize_text_field( (string) ( $user['username'] ?? '' ) );
			$profile_url  = esc_url_raw( (string) ( $user_links['html'] ?? '' ) );
			$photo_url    = esc_url_raw( (string) ( $links['html'] ?? '' ) );
			$download_loc = esc_url_raw( (string) ( $links['download_location'] ?? '' ) );

			$images[] = array(
				'id'                => sanitize_text_field( (string) ( $result['id'] ?? '' ) ),
				'description'       => sanitize_text_field( (string) ( $result['description'] ?? ( $result['alt_description'] ?? '' ) ) ),
				'url'               => esc_url_raw( (string) ( $urls['regular'] ?? '' ) ),
				'full'              => esc_url_raw( (string) ( $urls['full'] ?? '' ) ),
				'thumb'             => esc_url_raw( (string) ( $urls['small'] ?? '' ) ),
				'width'             => intval( $result['width'] ?? 0 ),
				'height'            => intval( $result['height'] ?? 0 ),
				'photographer'      => $photographer,
				'photographer_url'  => $profile_url,
				'unsplash_url'      => $photo_url,
				'attribution'       => $photographer && $username
					? sprintf(
						/* translators: 1: photographer name, 2: Unsplash username */
						__( 'Photo by %1$s (@%2$s) on Unsplash', 'advanced-animation' ),
						$photographer,
						$username
					)
					: '',
				'download_location' => $download_loc,
			);
		}

		self::remember_images( $images );

		return array(
			'type'   => 'image_search_results',
			'images' => $images,
		);
	}

	/**
	 * Remember download endpoints for image URLs returned by search.
	 *
	 * @param array $images Search result image rows.
	 */
	public static function remember_images( array $images ): void {
		$map = self::get_download_map();

		foreach ( $images as $image ) {
			if ( ! is_array( $image ) ) {
				continue;
			}
			$download = esc_url_raw( (string) ( $image['download_location'] ?? '' ) );
			if ( '' === $download ) {
				continue;
			}
			foreach ( array( 'url', 'full', 'thumb' ) as $key ) {
				$image_url = esc_url_raw( (string) ( $image[ $key ] ?? '' ) );
				if ( '' === $image_url ) {
					continue;
				}
				$map[ self::normalize_image_url( $image_url ) ] = $download;
			}
		}

		self::set_download_map( $map );
	}

	/**
	 * Ping Unsplash download endpoints for any Unsplash images found in content.
	 *
	 * @param string $content HTML or CSS that may embed images.unsplash.com URLs.
	 * @return int Number of download pings dispatched.
	 */
	public static function track_downloads_in_content( string $content ): int {
		if ( '' === $content || false === stripos( $content, 'images.unsplash.com' ) ) {
			return 0;
		}

		if ( ! preg_match_all( '#https?://images\.unsplash\.com/[^\s"\'\)<>]+#i', $content, $matches ) ) {
			return 0;
		}

		$map     = self::get_download_map();
		$tracked = array();
		$count   = 0;

		foreach ( $matches[0] as $raw_url ) {
			$key = self::normalize_image_url( $raw_url );
			if ( isset( $tracked[ $key ] ) ) {
				continue;
			}
			$tracked[ $key ] = true;

			$download = $map[ $key ] ?? '';
			if ( '' === $download ) {
				continue;
			}

			if ( self::track_download( $download ) ) {
				++$count;
			}
		}

		return $count;
	}

	/**
	 * Notify Unsplash that a photo was used (API guideline).
	 *
	 * @param string $download_location Download endpoint from the API response.
	 * @return bool True when the request was dispatched.
	 */
	public static function track_download( string $download_location ): bool {
		$download_location = esc_url_raw( $download_location );
		if ( '' === $download_location ) {
			return false;
		}

		$api_key = Connector_Settings::get_unsplash_api_key();
		if ( '' === $api_key ) {
			return false;
		}

		$url = add_query_arg( 'client_id', $api_key, $download_location );
		wp_remote_get(
			$url,
			array(
				'timeout'  => 5,
				'blocking' => false,
				'headers'  => array(
					'Accept-Version' => 'v1',
				),
			)
		);

		return true;
	}

	/**
	 * Normalize an Unsplash CDN URL for map lookups (strip query string).
	 *
	 * @param string $url Image URL.
	 * @return string
	 */
	public static function normalize_image_url( string $url ): string {
		$parts = wp_parse_url( $url );
		if ( ! is_array( $parts ) || empty( $parts['host'] ) || empty( $parts['path'] ) ) {
			return untrailingslashit( esc_url_raw( $url ) );
		}
		$scheme = ! empty( $parts['scheme'] ) ? $parts['scheme'] : 'https';
		return $scheme . '://' . $parts['host'] . $parts['path'];
	}

	/**
	 * @return array<string, string>
	 */
	private static function get_download_map(): array {
		$user_id = get_current_user_id();
		$key     = self::DOWNLOAD_MAP_TRANSIENT_PREFIX . $user_id;
		$map     = get_transient( $key );
		return is_array( $map ) ? $map : array();
	}

	/**
	 * @param array<string, string> $map URL path => download_location.
	 */
	private static function set_download_map( array $map ): void {
		$user_id = get_current_user_id();
		$key     = self::DOWNLOAD_MAP_TRANSIENT_PREFIX . $user_id;
		set_transient( $key, $map, HOUR_IN_SECONDS );
	}
}