<?php

	class SearchACFBetterSearch {

		function __construct() {

			$this->getDatabaseClass();
			$this->loadSettings();

			$this->loadFilters();

		}

		private function getDatabaseClass() {

			global $wpdb;

			$this->wpdb = $wpdb;

		}

		private function loadSettings() {

			if (get_option('acfbs_fields_types') !== false) {

				$this->fieldsTypes = is_array(get_option('acfbs_fields_types')) ? get_option('acfbs_fields_types') : array();

			} else {

				$this->fieldsTypes = array('text', 'textarea', 'wysiwyg');

			}


			if (get_option('acfbs_whole_phrases') !== false) {

				$this->wholePhrases = get_option('acfbs_whole_phrases') ? true : false;

			} else {

				$this->wholePhrases = false;

			}

		}

		private function loadFilters() {

			add_filter('posts_search',  array($this, 'sqlWhere'),    10, 2); 
			add_filter('posts_join',    array($this, 'sqlJoin'),     10, 2);
			add_filter('posts_request', array($this, 'sqlDistinct'), 10, 2); 

		}

		public function sqlWhere($where, $query) {

			if (!isset($query->query_vars['s']) || empty($query->query_vars['s']))
				return $where;


			$acfConditions       = $this->getACFConditions($query->query_vars['s']);
			$wordpressConditions = $this->getDefaultWordPressConditions($query->query_vars['s']);
			
			$where = 'AND (' . $acfConditions . ' OR ' . $wordpressConditions . ')';

			return $where;

		}

		private function getACFConditions($words) {

			if (!$this->fieldsTypes)
				return '(1 = 2)';


			$words           = !$this->wholePhrases ? explode(' ', $words) : array($words);
			$wordsConditions = array();

			foreach ($words as $word) {

				$wordsConditions[] = 'a.meta_value LIKE \'%' . $word . '%\'';

			}

			$wordsConditions = '(' . implode(') AND (', $wordsConditions) . ')';
			$conditions      = '(' . $wordsConditions . ' AND (b.meta_id = a.meta_id + 1) AND (c.post_name = b.meta_value))';

			return $conditions;

		}

		private function getDefaultWordPressConditions($words) {

			$words           = !$this->wholePhrases ? explode(' ', $words) : array($words);
			$wordsConditions = array();

			foreach ($words as $word) {

				$wordConditions   = array();
				$wordConditions[] = '(' . $this->wpdb->posts . '.post_title LIKE \'%' . $word . '%\')';
				$wordConditions[] = '(' . $this->wpdb->posts . '.post_content LIKE \'%' . $word . '%\')';
				$wordConditions[] = '(' . $this->wpdb->posts . '.post_excerpt LIKE \'%' . $word . '%\')';

				$wordsConditions[] = '(' . implode(' OR ', $wordConditions) . ')';

			}

			if (count($wordsConditions) > 1) {

				$conditions = '(' . implode(' AND ', $wordsConditions) . ')';

			} else {

				$conditions = $wordsConditions[0];

			}

			return $conditions;

		}

		public function sqlJoin($join, $query) {

			if (empty($query->query_vars['s']))
				return $join;

			if (!$this->fieldsTypes)
				return $join;


			$parts   = array();
			$parts[] = 'LEFT JOIN ' . $this->wpdb->postmeta . ' AS a ON (a.post_id = ' . $this->wpdb->posts . '.ID)';
			$parts[] = 'LEFT JOIN ' . $this->wpdb->postmeta . ' AS b ON (b.post_id = ' . $this->wpdb->posts . '.ID)';
			$parts[] = 'LEFT JOIN ' . $this->wpdb->posts . ' AS c ON ' . $this->getFieldsTypesConditions();
			$join   .= implode(' ', $parts);

			return $join;

		}

		private function getFieldsTypesConditions() {

			$typesConditions  = array();
			$conditions       = array();

			foreach ($this->fieldsTypes as $type) {

				$typesConditions[] = '(c.post_content LIKE \'%:"' . $type. '"%\')';

			}

			$conditions[] = '(c.post_type = \'acf-field\')';

			if (count($typesConditions) > 1) {

				$conditions[] = '(' . implode(' OR ', $typesConditions) . ')';

			} else {

				$conditions[] = $typesConditions[0];

			}
			
			$conditions = '(' . implode(' AND ', $conditions) . ')';

			return $conditions;

		}

		public function sqlDistinct($sql, $query) {

			if (empty($query->query_vars['s']))
				return $sql;


			$sql = str_replace('SELECT', 'SELECT DISTINCT', $sql);

			return $sql;

		}

	}