<?php
/**
 * RWPAI Plugin Public Functions
 *
 * @package AI_Agent
 */

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

/**
 * Get the language translation pack for the TTS plugin or list available translations.
 *
 * This function has two modes:
 * 1. **List mode** (no 'lang' param): Returns list of available translation files
 * 2. **Get mode** (with 'lang' param): Returns specific translation content
 *
 * It supports language codes in the format "en-US", "fr-CA", etc., but only the first
 * part of the code (e.g., "en" from "en-US") is used to locate the translation file.
 *
 * Priority order for translation lookup:
 * 1. wp-content/uploads/ai-agent/translations/{lang}.json (user custom)
 * 2. public/translations/{lang}.json (plugin default)
 * 3. Fallback to English (en.json) following the same priority
 *
 * @param WP_REST_Request $request The REST API request object.
 *     Optional parameters:
 *     - 'lang' (string): Language code (e.g., 'en', 'fr'). If not provided, lists all files.
 *     - 'folder' (string): 'plugin' (default) or 'upload' to specify which directory to list/read from.
 *
 * @return array|WP_Error Returns translation array, list of files, or WP_Error.
 *
 * Example usage (via REST API):
 * GET /wp-json/natuteto/v1/localization
 * Returns: ["en.json", "fr.json", "es.json"]
 *
 * GET /wp-json/natuteto/v1/localization?folder=upload
 * Returns: list of files in upload directory
 *
 * GET /wp-json/natuteto/v1/localization?lang=en-US
 * Returns: contents of translation file
 */
function rwpai_get_language_pack( $request ) {
	// Get parameters.
	$lang   = sanitize_text_field( $request->get_param( 'lang' ) );
	$folder = sanitize_text_field( $request->get_param( 'folder' ) );

	// Define directories.
	$upload_dir = wp_upload_dir();
	$custom_dir = trailingslashit( $upload_dir['basedir'] ) . 'ai-agent/translations/';
	$plugin_dir = RWPAI_PLUGIN_DIR . 'public/translations/';

	// LIST MODE: If no lang parameter provided, list all available translation files.
	if ( empty( $lang ) ) {
		$target_dir = $plugin_dir; // default to plugin directory.

		if ( 'upload' === $folder ) {
			$target_dir = $custom_dir;
			// Create directory if it doesn't exist for upload folder.
			if ( ! file_exists( $target_dir ) ) {
				wp_mkdir_p( $target_dir );
			}
		}

		if ( ! is_dir( $target_dir ) ) {
			return array();
		}

		// Read directory and filter for .json files.
		$files = array();
		$dh    = opendir( $target_dir );
		if ( false !== $dh ) {
			// phpcs:ignore Squiz.PHP.DisallowMultipleAssignments.FoundInControlStructure
			while ( false !== ( $entry = readdir( $dh ) ) ) {
				if ( '.' === $entry || '..' === $entry ) {
					continue;
				}
				// Only include .json files.
				if ( is_file( $target_dir . $entry ) && '.json' === substr( $entry, -5 ) ) {
					$files[] = $entry;
				}
			}
			closedir( $dh );
		}

		// Sort alphabetically.
		sort( $files );

		return rest_ensure_response(
			array(
				'status' => true,
				'data'   => $files,
			)
		);
	}

	// GET MODE: Return specific translation content.
	// Take only the first part before '-' (e.g., 'en' from 'en-US').
	$lang = explode( '-', $lang )[0];

	// If folder is specified, only check that specific folder.
	if ( 'upload' === $folder ) {
		$custom_file = $custom_dir . "{$lang}.json";
		if ( file_exists( $custom_file ) ) {
			// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents -- Reading local file, not remote.
			$content = file_get_contents( $custom_file );
			return json_decode( $content, true );
		}
		return new WP_Error(
			'not_found',
			'Translation not found in upload directory: ' . $lang,
			array( 'status' => 404 )
		);
	} elseif ( 'plugin' === $folder ) {
		$plugin_file = $plugin_dir . "{$lang}.json";
		if ( file_exists( $plugin_file ) ) {
			// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents -- Reading local file, not remote.
			$content = file_get_contents( $plugin_file );
			return json_decode( $content, true );
		}
		return new WP_Error(
			'not_found',
			'Translation not found in plugin directory: ' . $lang,
			array( 'status' => 404 )
		);
	}

	// Default: Check both with priority (custom first, then plugin).
	// Check custom translation first (user override).
	$custom_file = $custom_dir . "{$lang}.json";
	if ( file_exists( $custom_file ) ) {
		// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents -- Reading local file, not remote.
		$content = file_get_contents( $custom_file );
		return json_decode( $content, true );
	}

	// Check plugin default translation.
	$plugin_file = $plugin_dir . "{$lang}.json";
	if ( file_exists( $plugin_file ) ) {
		// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents -- Reading local file, not remote.
		$content = file_get_contents( $plugin_file );
		return json_decode( $content, true );
	}

	// Fallback to English - check custom first, then plugin.
	$custom_en = $custom_dir . 'en.json';
	if ( file_exists( $custom_en ) ) {
		// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents -- Reading local file, not remote.
		$content = file_get_contents( $custom_en );
		return json_decode( $content, true );
	}

	$plugin_en = $plugin_dir . 'en.json';
	if ( file_exists( $plugin_en ) ) {
		// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents -- Reading local file, not remote.
		$content = file_get_contents( $plugin_en );
		return json_decode( $content, true );
	}

	// If even English is missing, return error.
	return new WP_Error(
		'not_found',
		'Translation not found: ' . $lang,
		array( 'status' => 404 )
	);
}

/**
 * Upload a custom translation file.
 *
 * This function allows administrators to upload custom translation JSON files
 * that will override the default plugin translations. The uploaded file is saved
 * to wp-content/uploads/ai-agent/translations/.
 *
 * @param WP_REST_Request $request The REST API request object containing:
 *                                 - 'lang' (string): Language code (e.g., 'en', 'fr', 'es').
 *                                 - 'translation' (array): Translation data as a JSON object.
 *
 * @return WP_REST_Response|WP_Error Response with success status or error.
 *
 * Example usage (via REST API):
 * POST /wp-json/natuteto/v1/localization/upload
 * Body: {
 *   "lang": "en",
 *   "translation": {
 *     "key1": "value1",
 *     "key2": "value2"
 *   }
 * }
 */
function rwpai_upload_language_pack( WP_REST_Request $request ) {
	// Get and validate language code.
	$lang = sanitize_text_field( $request->get_param( 'lang' ) );
	if ( empty( $lang ) ) {
		return new WP_Error(
			'missing_lang',
			'Language code is required.',
			array( 'status' => 400 )
		);
	}

	// Take only the first part before '-' (e.g., 'en' from 'en-US').
	$lang = explode( '-', $lang )[0];

	// Validate language code format (2-11 letter code).
	if ( ! preg_match( '/^[a-z]{2,11}$/', $lang ) ) {
		return new WP_Error(
			'invalid_lang',
			'Invalid language code format. Use 2-11 letter codes like "en", "fr", "es".',
			array( 'status' => 400 )
		);
	}

	// Get translation data.
	$translation = $request->get_param( 'translation' );
	if ( empty( $translation ) || ! is_array( $translation ) ) {
		return new WP_Error(
			'missing_translation',
			'Translation data is required and must be a JSON object.',
			array( 'status' => 400 )
		);
	}

	// Prepare upload directory.
	$upload_dir = wp_upload_dir();
	$custom_dir = trailingslashit( $upload_dir['basedir'] ) . 'ai-agent/translations/';

	// Create directory if it doesn't exist.
	if ( ! file_exists( $custom_dir ) ) {
		// phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_mkdir
		if ( ! wp_mkdir_p( $custom_dir ) ) {
			return new WP_Error(
				'mkdir_failed',
				'Failed to create translations directory.',
				array( 'status' => 500 )
			);
		}
	}

	// Prepare file path.
	$file_path = $custom_dir . $lang . '.json';

	// Convert translation array to JSON.
	$json_content = wp_json_encode( $translation, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE );
	if ( false === $json_content ) {
		return new WP_Error(
			'json_encode_failed',
			'Failed to encode translation data to JSON.',
			array( 'status' => 500 )
		);
	}

	// Write file.
	// phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_file_put_contents
	$result = file_put_contents( $file_path, $json_content );

	if ( false === $result ) {
		return new WP_Error(
			'write_failed',
			'Failed to write translation file.',
			array( 'status' => 500 )
		);
	}

	return rest_ensure_response(
		array(
			'status'  => true,
			'message' => 'Translation uploaded successfully.',
			'lang'    => $lang,
			'path'    => str_replace( $upload_dir['basedir'], '', $file_path ),
		)
	);
}

/**
 * Delete a custom translation file.
 *
 * This function allows administrators to delete custom translation JSON files
 * from wp-content/uploads/ai-agent/translations/
 * Note: This only deletes custom translations, not plugin default translations.
 *
 * @param WP_REST_Request $request The REST API request object containing:.
 *                                 - 'lang' (string): Language code (e.g., 'en', 'fr', 'es').
 *
 * @return WP_REST_Response|WP_Error Response with success status or error.
 *
 * Example usage (via REST API):
 * DELETE /wp-json/natuteto/v1/localization?lang=en
 * Returns: {"status": true, "message": "Translation deleted successfully."}
 */
function rwpai_delete_language_pack( WP_REST_Request $request ) {
	// Get and validate language code.
	$lang = sanitize_text_field( $request->get_param( 'lang' ) );
	if ( empty( $lang ) ) {
		return new WP_Error(
			'missing_lang',
			'Language code is required.',
			array( 'status' => 400 )
		);
	}

	// Take only the first part before '-' (e.g., 'en' from 'en-US').
	$lang = explode( '-', $lang )[0];

	// Validate language code format (2-11 letter code).
	if ( ! preg_match( '/^[a-z]{2,11}$/', $lang ) ) {
		return new WP_Error(
			'invalid_lang',
			'Invalid language code format. Use 2-11 letter codes like "en", "fr", "es".',
			array( 'status' => 400 )
		);
	}

	// Prepare upload directory path.
	$upload_dir = wp_upload_dir();
	$custom_dir = trailingslashit( $upload_dir['basedir'] ) . 'ai-agent/translations/';
	$file_path  = $custom_dir . $lang . '.json';

	// Check if file exists.
	if ( ! file_exists( $file_path ) ) {
		return rest_ensure_response(
			array(
				'status'  => true,
				'message' => 'Translation file not found: ' . $lang . '.json',
				'lang'    => $lang,
			)
		);
	}

	// Security check: ensure we're only deleting from the custom translations directory.
	$real_custom_dir = realpath( $custom_dir );
	$real_file_path  = realpath( $file_path );

	if ( false === $real_custom_dir || false === $real_file_path || strpos( $real_file_path, $real_custom_dir ) !== 0 ) {
		return new WP_Error(
			'forbidden',
			'Cannot delete files outside custom translations directory.',
			array( 'status' => 403 )
		);
	}

	// Delete the file.
	// phpcs:ignore WordPress.WP.AlternativeFunctions.unlink_unlink
	if ( ! unlink( $file_path ) ) {
		return new WP_Error(
			'delete_failed',
			'Failed to delete translation file.',
			array( 'status' => 500 )
		);
	}

	return rest_ensure_response(
		array(
			'status'  => true,
			'message' => 'Translation deleted successfully.',
			'lang'    => $lang,
		)
	);
}


/**
 * Handles REST request for sample posts.
 *
 * @param WP_REST_Request $request The REST request providing optional filters.
 *
 * @return WP_REST_Response The response containing sample post data.
 */
function rwpai_get_sample_post( $request ) {
	$post_type = $request->get_param( 'type' ) ?? 'post';

	$args = array(
		'post_type'      => $post_type,
		'posts_per_page' => 2,
		'post_status'    => 'publish',
		'orderby'        => 'date',
		'order'          => 'DESC',
	);

	$posts = get_posts( $args );

	if ( empty( $posts ) ) {
		return rest_ensure_response( array() );
	}

	$data = array_map(
		function ( $post ) {
			return array(
				'title' => get_the_title( $post ),
				'url'   => get_permalink( $post ),
			);
		},
		$posts
	);

	return rest_ensure_response( $data );
}


/**
 * Get list of all post categories.
 *
 * @return array List of categories with id, name, and slug.
 */
function rwpai_get_post_categories() {
	$cats = get_categories(
		array(
			'hide_empty' => false,
		)
	);

	return array_map(
		function ( $cat ) {
			return array(
				'id'   => $cat->term_id,
				'name' => $cat->name,
				'slug' => $cat->slug,
			);
		},
		$cats
	);
}