<?php

//this is a workaround because we can't use closures in order to support php < 5.3
class tsml_filter_meetings {

	var $day;
	var $distance;
	var $distance_units;
	var $district_id;
	var $group_id;
	var $latitude;
	var $location_id;
	var $longitude;
	var $now;
	var $query;
	var $region_id;
	var $searchable_keys;
	var $time;
	var $type;

	//sanitize and save arguments (won't be passed to a database)
	function __construct($arguments) {

		if (!empty($arguments['day']) || (isset($arguments['day']) && $arguments['day'] == 0)) {
			$this->day = is_array($arguments['day']) ? array_map('intval', $arguments['day']) : array(intval($arguments['day']));
		}

		if (!empty($arguments['district'])) {
			$this->district_id = is_array($arguments['district']) ? array_map('sanitize_title', $arguments['district']) : array(sanitize_title($arguments['district']));
			//we are recieving district slugs, need to convert to IDs (todo save this in the cache)
			$this->district_id = array_map(array($this, 'get_district_id'), $this->district_id);
		}

		if (!empty($arguments['group_id'])) {
			$this->group_id = is_array($arguments['group_id']) ? array_map('intval', $arguments['group_id']) : array(intval($arguments['group_id']));
		}

		if (!empty($arguments['latitude']) && !empty($arguments['longitude'])) {
			$this->latitude = floatval($arguments['latitude']);
			$this->longitude = floatval($arguments['longitude']);
			$this->distance_units = (!empty($arguments['longitude']) && $arguments['longitude'] == 'km') ? 'km' : 'mi';
			if (!empty($arguments['distance'])) {
				$this->distance = floatval($arguments['distance']);
			}
		}

		if (!empty($arguments['location_id'])) {
			$this->location_id = is_array($arguments['location_id']) ? array_map('intval', $arguments['location_id']) : array(intval($arguments['location_id']));
		}

		if (!empty($arguments['query'])) {
			$this->searchable_keys = array('name', 'notes', 'location', 'location_notes', 'formatted_address', 'group', 'group_notes');
			$this->query = array_map('sanitize_text_field', array_filter(array_unique(explode(' ', $arguments['query']))));
		}

		if (!empty($arguments['region'])) {
			$this->region_id = is_array($arguments['region']) ? array_map('sanitize_title', $arguments['region']) : array(sanitize_title($arguments['region']));
			//we are recieving region slugs, need to convert to IDs (todo save this in the cache)
			$this->region_id = array_map(array($this, 'get_region_id'), $this->region_id);
			//region_id is now an array of arrays because regions can have children
			$return = array();
			foreach ($this->region_id as $region_id_array) {
				$return = array_merge($return, $region_id_array);
			}
			$this->region_id = $return;
		}

		if (!empty($arguments['time'])) {
			$this->time = is_array($arguments['time']) ? array_map('sanitize_title', $arguments['time']) : array(sanitize_title($arguments['time']));
			if (in_array('upcoming', $this->time)) {
				$this->now = current_time('H:i');
			}
		}

		if (!empty($arguments['type'])) {
			$this->type = is_array($arguments['type']) ? array_map('trim', $arguments['type']) : array(trim($arguments['type']));
		}

	}

	//run the filters
	function apply($meetings) {

		//run filters
		if ($this->day) $meetings = array_filter($meetings, array($this, 'filter_day'));
		if ($this->district_id) $meetings = array_filter($meetings, array($this, 'filter_district'));
		if ($this->group_id) $meetings = array_filter($meetings, array($this, 'filter_group'));
		if ($this->location_id) $meetings = array_filter($meetings, array($this, 'filter_location'));
		if ($this->query) $meetings = array_filter($meetings, array($this, 'filter_query'));
		if ($this->region_id) $meetings = array_filter($meetings, array($this, 'filter_region'));
		if ($this->time) $meetings = array_filter($meetings, array($this, 'filter_time'));
		if ($this->type) $meetings = array_filter($meetings, array($this, 'filter_type'));

		//if lat and lon are set then compute distances 
		if ($this->latitude && $this->longitude) {
			$meetings = array_map(array($this, 'calculate_distance'), $meetings);
			if ($this->distance) $meetings = array_filter($meetings, array($this, 'filter_distance'));
		}

		//return data
		return array_values($meetings);
	}

	//calculate distance to meeting
	function calculate_distance($meeting) {
		if (!isset($meeting['latitude']) || !isset($meeting['longitude'])) return $meeting;
		$meeting['distance'] = rad2deg(acos(sin(deg2rad($this->latitude)) * sin(deg2rad($meeting['latitude'])) +  cos(deg2rad($this->latitude)) * cos(deg2rad($meeting['latitude'])) * cos(deg2rad($this->longitude - $meeting['longitude'])))) * 69.09;
		if ($this->distance_units == 'km') $meeting['distance'] *= 1.609344;
		$meeting['distance'] = round($meeting['distance'], 1);
		return $meeting;
	}

	//callback function to pass to array_filter
	function filter_day($meeting) {
		if (!isset($meeting['day'])) return false;
		return in_array($meeting['day'], $this->day);
	}

	//callback function to pass to array_filter
	function filter_distance($meeting) {
		if (!isset($meeting['distance'])) return false;
		return $meeting['distance'] < $this->distance;
	}

	//callback function to pass to array_filter
	function filter_district($meeting) {
		if (!isset($meeting['district_id'])) return false;
		return in_array($meeting['district_id'], $this->district_id);
	}

	//callback function to pass to array_filter
	function filter_group($meeting) {
		if (!isset($meeting['group_id'])) return false;
		return in_array($meeting['group_id'], $this->group_id);
	}

	//callback function to pass to array_filter
	function filter_location($meeting) {
		if (!isset($meeting['location_id'])) return false;
		return in_array($meeting['location_id'], $this->location_id);
	}

	//callback function to pass to array_filter
	function filter_query($meeting) {
		foreach ($this->query as $word) {
			$word_matches = false;
			foreach ($this->searchable_keys as $key) {
				if (isset($meeting[$key]) && stripos($meeting[$key], $word) !== false) {
					$word_matches = true;
					break;
				}
			}
			if (!$word_matches) return false;
		}
		return true;
	}

	//callback function to pass to array_filter
	function filter_region($meeting) {
		if (!isset($meeting['region_id'])) return false;
		return in_array($meeting['region_id'], $this->region_id);
	}

	//callback function to pass to array_filter
	function filter_time($meeting) {
		if (!isset($meeting['time'])) return false;
		foreach ($this->time as $time) {
			if ($time == 'morning') {
				return (strcmp('04:00', $meeting['time']) <= 0 && strcmp('11:59', $meeting['time']) >= 0);
			} elseif ($time == 'midday') {
				return (strcmp('11:00', $meeting['time']) <= 0 && strcmp('16:59', $meeting['time']) >= 0);
			} elseif ($time == 'evening') {
				return (strcmp('16:00', $meeting['time']) <= 0 && strcmp('20:59', $meeting['time']) >= 0);
			} elseif ($time == 'night') {
				return (strcmp('20:00', $meeting['time']) <= 0 || strcmp('04:59', $meeting['time']) >= 0);
			} elseif ($time == 'upcoming') {
				return (strcmp($this->now, $meeting['time']) <= 0);
			}
		}
	}

	//callback function to pass to array_filter
	function filter_type($meeting) {
		if (!isset($meeting['types'])) return false;
		return array_intersect($meeting['types'], $this->type);
	}

	//function to get district id from slug
	function get_district_id($slug) {
		$term = get_term_by('slug', $slug, 'tsml_district');
		return $term->term_id;
	}

	//function to get region id from slug, as well as child region ids
	function get_region_id($slug) {
		$term = get_term_by('slug', $slug, 'tsml_region');
		$children = get_term_children($term->term_id, 'tsml_region');
		return array_merge(array($term->term_id), $children);
	}

}