<?php

namespace Boxzilla;

class BoxLoader {

	/**
	 * @var Plugin
	 */
	private $plugin;

	/**
	 * @var array
	 */
	private $box_ids_to_load = array();

	/**
	 * @var array
	 */
	protected $options;

	/**
	 * Constructor
	 *
	 * @param Plugin $plugin
	 * @param array $options
	 */
	public function __construct( Plugin $plugin, array $options ) {
		$this->plugin = $plugin;
		$this->options = $options;
	}

	/**
	 * Initializes the plugin, runs on `wp` hook.
	 */
	public function init() {

		$this->box_ids_to_load = $this->filter_boxes();

		// Only add other hooks if necessary
		if( count( $this->box_ids_to_load ) > 0 ) {
			add_action( 'wp_enqueue_scripts', array( $this, 'load_assets' ), 90 );
		}
	}

	/**
	 * Get global rules for all boxes
	 *
	 * @return array
	 */
	protected function get_filter_rules() {
		$rules = get_option( 'boxzilla_rules', array() );

		if( ! is_array( $rules ) ) {
			return array();
		}

		return $rules;
	}


	/**
	 * Match a string against an array of patterns, glob-style.
	 *
	 * @param string $string
	 * @param array $patterns
	 *
	 * @return boolean
	 */
	protected function match_patterns( $string, $patterns ) {
		$string = strtolower( $string );

		foreach( $patterns as $pattern ) {

			$pattern = strtolower( $pattern );

			if( function_exists( 'fnmatch' ) ) {
				$match = fnmatch( $pattern, $string );
			} else {
				$match = ( $pattern === $string );
			}

			if( $match ) {
				return true;
			}
		}

		return false;
	}

	/**
	 * Check if this rule passes (conditional matches expected value)
	 *
	 * @param string $condition
	 * @param string $value
	 * @param boolean $qualifier
	 *
	 * @return bool
	 */
	protected function match_rule( $condition, $value, $qualifier = true ) {

		$matched = false;

		// cast value to array & trim whitespace or excess comma's
		$value = array_map( 'trim', explode( ',', rtrim( trim( $value ), ',' ) ) );

		switch ( $condition ) {
			case 'everywhere';
				$matched = true;
				break;

			case 'is_url':
				$matched = $this->match_patterns( $_SERVER['REQUEST_URI'], $value );
				break;

			case 'is_referer':
				if( ! empty( $_SERVER['HTTP_REFERER'] ) ) {
					$referer = $_SERVER['HTTP_REFERER'];
					$matched = $this->match_patterns( $referer, $value );
				}
				break;

			case 'is_post_type':
				$post_type = (string) get_post_type();
				$matched = in_array( $post_type, (array) $value );
				break;

			case 'is_single':
			case 'is_post':
				$matched = is_single( $value );
				break;

			case 'is_post_in_category':
				$matched = is_singular( 'post' ) && has_category( $value );
				break;


			case 'is_page':
				$matched = is_page( $value );
				break;

		}

		// if qualifier is set to false, we need to reverse this value here.
		if( ! $qualifier ) {
			$matched = ! $matched;
		}

		return $matched;
	}

	/**
	 * Checks which boxes should be loaded for this request.
	 *
	 * @return array
	 */
	private function filter_boxes() {

		$box_ids_to_load = array();
		$rules = $this->get_filter_rules();

		foreach( $rules as $box_id => $box_rules ) {

			$matched = false;
			$comparision = isset( $box_rules['comparision'] ) ? $box_rules['comparision'] : 'any';

			// loop through all rules for all boxes
			foreach ( $box_rules as $rule ) {

				// skip faulty values (and comparision rule)
				if( empty( $rule['condition'] ) ) {
					continue;
				}

				$qualifier = isset( $rule['qualifier'] ) ? $rule['qualifier'] : true;
				$matched = $this->match_rule( $rule['condition'], $rule['value'], $qualifier );

				// break out of loop if we've already matched
				if( $comparision === 'any' && $matched ) {
					break;
				}

				// no need to continue if this rule didn't match
				if( $comparision === 'all' && ! $matched ) {
					break;
				}
			}

			// value of $matched at this point determines whether box should be loaded
			$load_box = $matched;

			/**
			 * Filters whether a box should be loaded into the page HTML.
			 *
			 * The dynamic portion of the hook, `$box_id`, refers to the ID of the box. Return true if you want to output the box.
			 *
			 * @param boolean $load_box
			 */
			$load_box = apply_filters( 'boxzilla_load_box_' . $box_id, $load_box );

			/**
			 * Filters whether a box should be loaded into the page HTML.
			 *
			 * @param boolean $load_box
			 * @param int $box_id
			 */
			$load_box = apply_filters( 'boxzilla_load_box', $load_box, $box_id );

			// if matched, box should be loaded on this page
			if ( $load_box ) {
				$box_ids_to_load[] = $box_id;
			}

		}

		return $box_ids_to_load;
	}

	/**
	* Load plugin styles
	*/
	public function load_assets() {
		$pre_suffix = defined( 'SCRIPT_DEBUG' ) && SCRIPT_DEBUG ? '' : '.min';

		// stylesheets
		wp_register_style( 'boxzilla', $this->plugin->url( '/assets/css/styles' . $pre_suffix . '.css' ), array(), $this->plugin->version() );

		// scripts
		wp_register_script( 'boxzilla',$this->plugin->url( '/assets/js/script' . $pre_suffix . '.js' ), array( 'jquery' ), $this->plugin->version(), true );

		// Finally, enqueue style.
		wp_enqueue_style( 'boxzilla' );
		wp_enqueue_script( 'boxzilla' );

		$this->pass_box_options();

		do_action( 'boxzilla_load_assets', $this );
	}

	/**
	 * Get an array of Box objects. These are the boxes that will be loaded for the current request.
	 *
	 * @return Box[]
	 */
	public function get_matched_boxes() {
		static $boxes;

		if( is_null( $boxes ) ) {

			if( count( $this->box_ids_to_load ) === 0 ) {
				$boxes = array();
				return $boxes;
			}

			// query Box posts
			$boxes = get_posts(
				array(
					'post_type' => 'boxzilla-box',
					'post_status' => 'publish',
					'post__in'    => $this->box_ids_to_load,
					'numberposts' => -1
				)
			);

			// create `Box` instances out of \WP_Post instances
			foreach ( $boxes as $key => $box ) {
				$boxes[ $key ] = new Box( $box );
			}
		}

		return $boxes;
	}

	/**
	 * Create array of Box options and pass it to JavaScript script.
	 */
	public function pass_box_options() {

		// create boxzilla_Global_Options object
		$plugin_options = $this->options;
		$boxes = $this->get_matched_boxes();

		$data = array(
			'testMode' => (boolean) $plugin_options['test_mode'],
			'boxes' => array_map( function(Box $box) { return $box->get_client_options(); }, $boxes ),
		);

		wp_localize_script( 'boxzilla', 'boxzilla_options', $data );
	}

}