<?php
/**
 * Frontend Assets Generator Cache
 *
 * @author Jegstudio
 * @since 1.0.0
 * @package gutenverse-framework
 */

namespace Gutenverse\Framework;

/**
 * Class Frontend Cache.
 *
 * @since 2.3.0:
 *      - Class renamed from Style_Cache to Frontend_Cache
 *      - Add function get_path_by_type to load different path
 *
 * @package gutenverse-framework
 */
class Frontend_Cache {
	/**
	 * Option Name.
	 *
	 * @var string
	 */
	public static $option_name = 'gutenverse-style-cache-id';

	/**
	 * Font Cache Name.
	 *
	 * @var string
	 */
	protected $font_cache_name;

	/**
	 * Script Cache Name.
	 *
	 * @var string
	 */
	protected $conditional_script_cache_name;

	/**
	 * Style Cache Name.
	 *
	 * @var string
	 */
	protected $conditional_style_cache_name;

	/**
	 * Init constructor.
	 */
	public function __construct() {
		// Perlu Test Schedule.
		add_action( 'wp_loaded', array( $this, 'schedule_cleanup_cron' ) );
		add_action( 'gutenverse_cleanup_cached_style', array( $this, 'cleanup_cached_style' ) );
		add_action( 'switch_theme', array( $this, 'delete_generated_files_when_switch_theme' ) );
		add_filter( 'cron_schedules', array( $this, 'add_custom_intervals' ) );

		// Reset Generator ID when this hook triggered.
		add_action( 'save_post', array( $this, 'generate_style_cache_id' ) );
		add_action( 'gutenverse_modify_global_variable', array( $this, 'generate_style_cache_id' ) );

		// Filter.
		add_filter( 'gutenverse_frontend_render_mechanism', array( $this, 'render_mechanism' ) );
		add_filter( 'gutenverse_bypass_generate_style', array( $this, 'bypass_generate_css' ), null, 3 );
		add_filter( 'gutenverse_bypass_generate_script', array( $this, 'bypass_script' ), null, 2 );
		add_filter( 'gutenverse_global_fonts', array( $this, 'global_fonts' ), null, 2 );
		add_filter( 'gutenverse_conditional_script_handles', array( $this, 'script_handles' ), null, 2 );
		add_filter( 'gutenverse_conditional_style_handles', array( $this, 'style_handles' ), null, 2 );
		add_filter( 'gutenverse_render_generated_style', array( $this, 'render_style' ), null, 4 );
		add_action( 'gutenverse_cache_preload_assets', array( $this, 'cache_preload_assets' ), null, 3 );
		add_filter( 'gutenverse_load_cached_preload_assets', array( $this, 'load_preload_assets' ), null, 3 );
	}

	/**
	 * Make preload assets cache
	 *
	 * @param string $assets  Assets string.
	 * @param string $type    Preload type.
	 * @param mixed  $post_id Post ID.
	 *
	 * @return void
	 */
	public function cache_preload_assets( $assets, $type = 'image', $post_id = false ) {
		$mechanism = apply_filters( 'gutenverse_frontend_render_mechanism', 'direct' );
		if ( 'file' === $mechanism && ! empty( $assets ) && '' !== $type ) {
			$name     = $this->get_preload_asset_filename( $type, $post_id );
			$filename = $this->get_file_name( $name, '.json' );
			$this->create_cache_file( $filename, wp_json_encode( $assets, true ), 'preload_assets' );
		}
	}

	/**
	 * Overwrite Render Mechanism
	 *
	 * @return string
	 */
	public function render_mechanism() {
		$options = get_option( 'gutenverse-settings' );

		if ( isset( $options['frontend_settings']['render_mechanism'] ) ) {
			$render_mechanism = $options['frontend_settings']['render_mechanism'];
			if ( ! empty( $render_mechanism ) ) {
				return $render_mechanism;
			}
		}
		return 'file';
	}

	/**
	 * Get Font Cache Name.
	 *
	 * @return string
	 */
	public function get_font_cache_filename() {
		return $this->font_cache_name;
	}

	/**
	 * Get Script Cache Name.
	 *
	 * @return string
	 */
	public function get_script_cache_filename() {
		return $this->conditional_script_cache_name;
	}

	/**
	 * Get Style Cache Name.
	 *
	 * @return string
	 */
	public function get_style_cache_filename() {
		return $this->conditional_style_cache_name;
	}

	/**
	 * Set Font Cache Name
	 *
	 * @param string $name Name of cache.
	 * @param string $type Type of generated css.
	 */
	public function set_font_cache_name( $name, $type ) {
		$cache_id       = $this->get_style_cache_id();
		$font_file_name = $name . '-font-' . $cache_id . '.json';

		if ( is_page() || is_single() && 'content' === $type ) {
			$this->font_cache_name = $font_file_name;
		} elseif ( 'template' === $type ) {
			$this->font_cache_name = $font_file_name;
		}
	}

	/**
	 * Set Modular Script Cache Name
	 *
	 * @param string $name Name of cache.
	 */
	public function set_conditional_script_cache_name( $name ) {
		$cache_id                            = $this->get_style_cache_id();
		$script_file_name                    = $name . '-script-' . $cache_id . '.json';
		$this->conditional_script_cache_name = $script_file_name;
	}

	/**
	 * Set Modular Style Cache Name
	 *
	 * @param string $name Name of cache.
	 */
	public function set_conditional_style_cache_name( $name ) {
		$cache_id                           = $this->get_style_cache_id();
		$style_file_name                    = $name . '-style-' . $cache_id . '.json';
		$this->conditional_style_cache_name = $style_file_name;
	}

	/**
	 * By Pass Populate Font.
	 *
	 * @param array $fonts Array of fonts.
	 *
	 * @return array
	 */
	public function global_fonts( $fonts ) {
		$filename  = $this->get_font_cache_filename();
		$mechanism = apply_filters( 'gutenverse_frontend_render_mechanism', 'direct' );

		if ( 'file' === $mechanism ) {
			if ( $this->is_file_exist( $filename, 'font' ) ) {
				$fonts = $this->read_cache_file( $filename, 'font' );
				return json_decode( $fonts, true );
			} else {
				$this->create_cache_file( $filename, wp_json_encode( $fonts, true ), 'font' );
			}
		}

		return $fonts;
	}

	/**
	 * By Pass Script Loop Attribute.
	 *
	 * @param array $handles Array of script handles.
	 *
	 * @return array
	 */
	public function script_handles( $handles ) {
		$filename  = $this->get_script_cache_filename();
		$mechanism = apply_filters( 'gutenverse_frontend_render_mechanism', 'direct' );

		if ( 'file' === $mechanism ) {
			if ( $this->is_file_exist( $filename, 'conditional_js' ) ) {
				$handles = $this->read_cache_file( $filename, 'conditional_js' );
				return json_decode( $handles, true );
			} else {
				$this->create_cache_file( $filename, wp_json_encode( $handles, true ), 'conditional_js' );
			}
		}

		return $handles;
	}

	/**
	 * By Pass Script Loop Attribute.
	 *
	 * @param array $handles Array of style handles.
	 *
	 * @return array
	 */
	public function style_handles( $handles ) {
		$filename  = $this->get_style_cache_filename();
		$mechanism = apply_filters( 'gutenverse_frontend_render_mechanism', 'direct' );

		if ( 'file' === $mechanism ) {
			if ( $this->is_file_exist( $filename, 'conditional_css' ) ) {
				$handles = $this->read_cache_file( $filename, 'conditional_css' );
				return json_decode( $handles, true );
			} else {
				$this->create_cache_file( $filename, wp_json_encode( $handles, true ), 'conditional_css' );
			}
		}

		return $handles;
	}

	/**
	 * Check if we going to by pass css generation.
	 *
	 * @param boolean $flag Flag.
	 * @param string  $name Name of file.
	 * @param string  $type Type of generated css.
	 *
	 * @return bool
	 */
	public function bypass_generate_css( $flag, $name, $type ) {
		$this->set_font_cache_name( $name, $type );

		$mechanism = apply_filters( 'gutenverse_frontend_render_mechanism', 'direct' );
		$filename  = $this->get_file_name( $name );

		if ( 'file' === $mechanism && $this->is_file_exist( $filename, 'css' ) ) {
			$this->inject_to_header( $filename, $type );
			return true;
		}

		return $flag;
	}

	/**
	 * Load preload assets.
	 *
	 * @param string $type     Preload Type.
	 * @param mixed  $post_id  Post ID.
	 *
	 * @return string
	 */
	public function get_preload_asset_filename( $type, $post_id ) {
		$name = "gutenverse-preload-{$type}";
		if ( $post_id ) {
			$name = "{$name}-{$post_id}";
		}
		return $name;
	}

	/**
	 * Load preload assets.
	 *
	 * @param array  $preloads Preload list.
	 * @param string $type     Preload Type.
	 * @param mixed  $post_id  Post ID.
	 *
	 * @return array
	 */
	public function load_preload_assets( $preloads, $type = 'image', $post_id = false ) {
		$mechanism     = apply_filters( 'gutenverse_frontend_render_mechanism', 'direct' );
		$filename      = $this->get_preload_asset_filename( $type, $post_id );
		$cache_preload = $this->get_file_name( $filename, '.json' );
		if ( 'file' === $mechanism && $this->is_file_exist( $cache_preload, 'preload_assets' ) ) {
			$handles  = $this->read_cache_file( $cache_preload, 'preload_assets' );
			$content  = json_decode( $handles, true );
			$preloads = array_merge( $preloads, $content );
		}

		return $preloads;
	}

	/**
	 * Check if we going to by pass script checking.
	 *
	 * @param boolean $flag Flag.
	 * @param string  $name Name of file.
	 *
	 * @return bool
	 */
	public function bypass_script( $flag, $name ) {
		$this->set_conditional_script_cache_name( $name );
		$this->set_conditional_style_cache_name( $name );
		$mechanism = apply_filters( 'gutenverse_frontend_render_mechanism', 'direct' );
		$filename  = $this->get_file_js_name( $name );

		if ( 'file' === $mechanism && $this->is_file_exist( $filename, 'conditional_js' ) ) {
			return true;
		}

		return $flag;
	}

	/**
	 * Get File Name.
	 *
	 * @param string $name Name of file.
	 *
	 * @return string
	 */
	public function get_file_js_name( $name ) {
		$cache_id         = $this->get_style_cache_id();
		$script_file_name = $name . '-script-' . $cache_id . '.json';
		return $script_file_name;
	}

	/**
	 * Delete Generated CSS & JSON when Switching Theme
	 */
	public function delete_generated_files_when_switch_theme() {
		delete_option( self::$option_name );

		$css_path = gutenverse_css_path();
		$this->delete_file( $css_path );

		$conditional_path = gutenverse_conditional_path();
		$this->delete_file( $conditional_path );
	}

	/**
	 * Add Custom Interval for Sceduler
	 *
	 * @param array $schedules Schedules.
	 *
	 * @return array
	 */
	public function add_custom_intervals( $schedules ) {
		$schedules['yearly']             = array(
			'interval' => 365 * 24 * 60 * 60, // 365 days in seconds
			'display'  => esc_html__( 'Once a Year', 'gutenverse-news' ),
		);
		$schedules['monthly']            = array(
			'interval' => 30 * 24 * 60 * 60, // 30 days in seconds
			'display'  => esc_html__( 'Once a Month', 'gutenverse-news' ),
		);
		$schedules['weekly']             = array(
			'interval' => 7 * 24 * 60 * 60, // 7 days in seconds
			'display'  => esc_html__( 'Every Week', 'gutenverse-news' ),
		);
		$schedules['every_two_days']     = array(
			'interval' => 2 * 24 * 60 * 60, // 2 days in seconds
			'display'  => esc_html__( 'Once Every 2 Days', 'gutenverse-news' ),
		);
		$schedules['daily']              = array(
			'interval' => 24 * 60 * 60, // 1 day in seconds
			'display'  => esc_html__( 'Daily', 'gutenverse-news' ),
		);
		$schedules['every_five_minutes'] = array(
			'interval' => 5 * 60, // 5 minutes in seconds
			'display'  => esc_html__( 'Once Every 5 Minutes', 'gutenverse-news' ),
		);
		return $schedules;
	}
	/**
	 * Schedule Delete Cron.
	 */
	public function schedule_cleanup_cron() {
		$options = get_option( 'gutenverse-settings' );
		// Safe access.
		$frontend = isset( $options['frontend_settings'] ) && is_array( $options['frontend_settings'] )
		? $options['frontend_settings']
		: array();

		$render_mechanism      = $frontend['render_mechanism'] ?? '';
		$file_delete_mechanism = $frontend['file_delete_mechanism'] ?? '';
		$file_delete_mechanism = '';

		$custom_schedule = $frontend['old_render_deletion_schedule'] ?? 'daily';

		$hook = 'gutenverse_cleanup_cached_style';

		// Validate schedule.
		$schedules = wp_get_schedules();
		if ( ! isset( $schedules[ $custom_schedule ] ) ) {
			$custom_schedule = 'daily';
		}

		// Check if feature should be active.
		$should_schedule = (
			( 'file' === $render_mechanism || ! $render_mechanism ) &&
			( 'auto' === $file_delete_mechanism )
		);

		// Get current scheduled event.
		$timestamp = wp_next_scheduled( $hook );

		// Get next midnight using WP timezone.
		$now      = current_time( 'timestamp' );
		$midnight = strtotime( 'tomorrow midnight', $now );

		// CASE 1: Should NOT be scheduled → clear if exists.
		if ( ! $should_schedule ) {
			if ( $timestamp ) {
				wp_clear_scheduled_hook( $hook );
			}
			return;
		}

		// CASE 2: Should be scheduled but not yet scheduled.
		if ( ! $timestamp ) {
			wp_schedule_event( $midnight, $custom_schedule, $hook );
			return;
		}

		// CASE 3: Already scheduled → check if rescheduling needed.
		$current_schedule = wp_get_schedule( $hook );

		if ( $current_schedule !== $custom_schedule ) {
			// Reschedule with new interval.
			wp_clear_scheduled_hook( $hook );
			wp_schedule_event( $midnight, $custom_schedule, $hook );
		}
	}

	/**
	 * Delete File if not Containing String.
	 *
	 * @param string $folder_path Folder Path.
	 * @param string $cache_id Cache Id.
	 *
	 * @return void
	 */
	public function delete_file( $folder_path, $cache_id = false ) {
		if ( ! is_dir( $folder_path ) ) {
			return;
		}
		$files = list_files( $folder_path );

		foreach ( $files as $file ) {
			if ( is_file( $file ) ) {
				$filename = basename( $file );
				if ( $cache_id ) {
					if ( strpos( $filename, $cache_id ) === false ) {
						wp_delete_file( $file );
					}
				} else {
					wp_delete_file( $file );
				}
			}
		}
	}

	/**
	 * Clean up cache style.
	 */
	public function cleanup_cached_style() {
		$cache_id = $this->get_style_cache_id();

		$css_path = gutenverse_css_path();
		$this->delete_file( $css_path, $cache_id );

		$conditional_path = gutenverse_conditional_path();
		$this->delete_file( $conditional_path, $cache_id );

		$preload_path = gutenverse_preload_assets_path();
		$this->delete_file( $preload_path, $cache_id );
	}

	/**
	 * Rolling cache ID.
	 */
	public function generate_style_cache_id() {
		$cache_id = wp_rand( 111111, 999999 );
		update_option( self::$option_name, $cache_id, true );
	}

	/**
	 * Get Cache ID.
	 *
	 * @return string
	 */
	public function get_style_cache_id() {
		return get_option( self::$option_name, 'initial-cache' );
	}

	/**
	 * Get File Name.
	 *
	 * @param string $name Name of file.
	 * @param string $mime Mime of file.
	 *
	 * @return string
	 */
	public function get_file_name( $name, $mime = '.css' ) {
		$cache_id = $this->get_style_cache_id();
		return $name . '-' . $cache_id . $mime;
	}

	/**
	 * Render Generated Style.
	 *
	 * @param string $flag render flag.
	 * @param string $name Name of file.
	 * @param string $style Generated Style.
	 * @param string $source Source of content.
	 *
	 * @return boolean
	 */
	public function render_style( $flag, $name, $style, $source ) {
		$mechanism = apply_filters( 'gutenverse_frontend_render_mechanism', 'direct' );

		if ( 'file' === $mechanism ) {
			$this->generate_and_render( $name, $style, $source );
			return true;
		}

		return $flag;
	}

	/**
	 * Generate and Render Style
	 *
	 * @param string $name Name of file.
	 * @param string $style Generated Style.
	 * @param string $source Source of content.
	 */
	public function generate_and_render( $name, $style, $source ) {
		$filename = $this->get_file_name( $name );
		$this->create_cache_file( $filename, $style, 'css' );
		$this->inject_to_header( $filename, $source );
	}

	/**
	 * Inject to header.
	 *
	 * @param string $filename with extension and style id.
	 * @param string $type Type of generate style cache.
	 */
	public function inject_to_header( $filename, $type ) {
		$cache_id = $this->get_style_cache_id();
		$file_url = gutenverse_css_url( $filename );
		$includes = array( 'gutenverse-frontend-style' );

		if ( gutenverse_pro_active() ) {
			$includes[] = 'gutenverse-pro-block';
		}

		wp_enqueue_style(
			'gutenverse-generated-' . $type,
			$file_url,
			$includes,
			$cache_id
		);
	}

	/**
	 * Initialize WP Filesystem.
	 */
	public function initialize_wp_filesystem() {
		if ( ! function_exists( 'WP_Filesystem' ) ) {
			require_once ABSPATH . 'wp-admin/includes/file.php';
		}
		WP_Filesystem();
	}

	/**
	 * Create File.
	 *
	 * @since 2.3.0: add this function to load different path
	 *
	 * @param string $type File type.
	 * @param string $filename File name with extension.
	 *
	 * @return bool
	 */
	protected function get_path_by_type( $type, $filename = '' ) {
		switch ( $type ) {
			case 'conditional_js':
			case 'conditional_css':
				return gutenverse_conditional_path( $filename );
			case 'preload_assets':
				return gutenverse_preload_assets_path( $filename );
			case 'css':
			case 'font':
			default:
				return gutenverse_css_path( $filename );
		}
	}

	/**
	 * Create File.
	 *
	 * @since 2.3.0: add $type to load different path
	 *
	 * @param string $filename File name with extension.
	 * @param string $content Style content.
	 * @param string $type File type.
	 *
	 * @return bool
	 */
	public function create_cache_file( $filename, $content, $type = 'css' ) {
		global $wp_filesystem;
		$this->initialize_wp_filesystem();

		$style_directory = $this->get_path_by_type( $type );
		$file_path       = $this->get_path_by_type( $type, $filename );

		if ( ! $wp_filesystem->is_dir( $style_directory ) ) {
			wp_mkdir_p( $style_directory );
		}

		if ( $wp_filesystem->put_contents( $file_path, $content, FS_CHMOD_FILE ) ) {
			defined( 'WP_DEBUG' ) && WP_DEBUG && gutenverse_rlog( 'File created with name : ' . $filename );
			return true;
		} else {
			defined( 'WP_DEBUG' ) && WP_DEBUG && gutenverse_rlog( 'Failed to create file with name : ' . $filename );
			return false;
		}
	}


	/**
	 * Read Cache File.
	 *
	 * @since 2.3.0: add $type to load different path
	 *
	 * @param string $filename File name.
	 * @param string $type File type.
	 *
	 * @return string
	 */
	public function read_cache_file( $filename, $type = 'css' ) {
		global $wp_filesystem;
		$this->initialize_wp_filesystem();
		$file_path = $this->get_path_by_type( $type, $filename );

		if ( $wp_filesystem->exists( $file_path ) ) {
			return $wp_filesystem->get_contents( $file_path );
		} else {
			return 'File does not exist.';
		}
	}

	/**
	 * Check if file exist.
	 *
	 * @since 2.3.0: add $type to load different path
	 *
	 * @param string $filename File name.
	 * @param string $type File type.
	 *
	 * @return bool
	 */
	public function is_file_exist( $filename, $type = 'css' ) {
		global $wp_filesystem;
		$this->initialize_wp_filesystem();

		$file_path = $this->get_path_by_type( $type, $filename );

		if ( $wp_filesystem->exists( $file_path ) ) {
			return true;
		} else {
			return false;
		}
	}
}
