search.class.php

Go to the documentation of this file.

<?php
class search {

        private $_registry;
        
        private $_table;

        function __construct($table, $opts=null) {
        
                $this->_registry = registry::instance();
                $this->_table = $table;
                $this->_highlight_range = gOpt($opts, 'highlight_range', 120);

        }

        private function clearSearchString($search_string) {

                $unconsidered = array("lo", "l", "il", "la", "i", "gli", "le", "uno", "un", "una", "un", "su", "sul", "sulla", "sullo", "sull", "in", "nel", "nello", "nella", "nell", "con", "di", "da", "dei", "d",  "della", "dello", "del", "dell", "che", "a", "dal", "è", "e", "per", "non", "si", "al", "ai", "allo", "all", "al", "o", "the", "a", "an", "on", "in", "with", "of", "which", "that", "is", "for", "to");

                $clean_string = strtolower($search_string);

                $clean_string = preg_replace("#\b(".preg_quote(implode("|", $unconsidered)).")\b#", "", $clean_string);
                $clean_string = preg_replace("#\W|(\s+)#", " ", $clean_string);

                $clean_string = preg_quote($clean_string);
        
                return $clean_string;

        }

        private function getKeywords($search_string) {
                
                $clean_string = $this->clearSearchString($search_string);

                $empty_array = array(""," ");

                return  array_diff(array_unique(explode(" ", $clean_string)), $empty_array);

        }

        public function makeQuery($selected_fields, $required_clauses, $weight_clauses){
        
                $final_keywords = 0;

                $selected = array();
                foreach($selected_fields as $f) {
                        $selected[] = is_array($f) ? $f['field'] : $f;
                }
                $relevance = "(";
                $occurrences = "(";
                $sqlwhere_r = "";
                $sqlwhere_w = "";
                $sql_where = '';
                foreach($required_clauses as $f=>$fp) {
                        if(is_array($fp)) {
                                if(isset($fp['inside']) && $fp['inside']) $sqlwhere_r .= "$f LIKE '%".$fp['value']."%' AND ";
                                elseif(isset($fp['begin']) && $fp['begin']) $sqlwhere_r .= "$f LIKE '".$fp['value']."%' AND ";
                                elseif(isset($fp['end']) && $fp['end']) $sqlwhere_r .= "$f LIKE '%".$fp['value']."' AND ";
                                elseif(isset($fp['field']) && $fp['field']) $sqlwhere_r .= "$f=".$fp['value']." AND ";
                                else $sqlwhere_r .= "$f='".$fp['value']."' AND ";
                        }
                        else {
                                $sqlwhere_r .= "$f='$fp' AND ";
                        }
                }
                foreach($weight_clauses as $f=>$fp) {
                        $search_keywords = $this->getKeywords($fp['value']);
                        $final_keywords += count($search_keywords);

                        foreach($search_keywords as $keyw) {
                                $occurrences .= "IFNULL(((LENGTH($f)-LENGTH(replace_ci($f,'$keyw','')))/LENGTH('$keyw')), 0) + ";
                                if(isset($fp['inside']) && $fp['inside']) {
                                        $relevance .= "(INSTR(`$f`, '".$keyw."')>0)*".$fp['weight']." + ";
                                        $sqlwhere_w .= "`$f` LIKE '%".$keyw."%' OR ";
                                }
                                else {
                                        $relevance .= "IFNULL(((`$f` REGEXP '[[:<:]]".$keyw."[[:>:]]')>0)*".$fp['weight'].", 0) + ";
                                        $sqlwhere_w .= "`$f` REGEXP '[[:<:]]".$keyw."[[:>:]]' OR ";
                                }
                        }
                }
                if($final_keywords) $sqlwhere_w = substr($sqlwhere_w, 0, strlen($sqlwhere_w)-4);
                $relevance .= "0)";
                $occurrences .= "0)";
                if($sqlwhere_r || $sqlwhere_w) {
                        $sqlwhere = "WHERE ";
                        if($sqlwhere_r) $sqlwhere .= $sqlwhere_r;
                        if($sqlwhere_w) $sqlwhere .= "(".$sqlwhere_w.")";
                        else $sqlwhere = substr($sqlwhere, 0, strlen($sqlwhere)-5);
                }
                $query = "SELECT ".implode(",", $selected).", $relevance AS relevance, $occurrences AS occurrences FROM $this->_table $sqlwhere ORDER BY relevance DESC, occurrences DESC";
                        
                return $final_keywords ? $query : false;

        }

        public function getSearchResults($selected_fields, $required_clauses, $weight_clauses) {
        
                $res = array();

                $query = $this->makeQuery($selected_fields, $required_clauses, $weight_clauses);

                if($query===false) return array();
                $rows = $this->_registry->db->queryResult($query);
                if(sizeof($rows)>0) {
                        $i = 0;
                        foreach($rows as $row) {
                                $res[$i] = array(); 
                                foreach($selected_fields as $f) {
                                        $res[$i]['relevance'] = $row['relevance'];
                                        $res[$i]['occurrences'] = $row['occurrences'];
                                        if(is_array($f) && isset($f['highlight']) && $f['highlight']) {
                                                $fp = $weight_clauses[$f['field']];
                                                $get_search_keywords = $this->getKeywords($fp['value']);
                                                $search_keywords = array();
                                                foreach($get_search_keywords as $kw) {
                                                        $search_keywords[] = preg_quote($kw);
                                                }
                                                $rexp = (isset($fp['inside']) && $fp['inside']) 
                                                        ? implode("|", $search_keywords) 
                                                        : "\b".implode("\b|\b", $search_keywords)."\b";
                                                if(preg_match("#(.){0,$this->_highlight_range}($rexp)(.){0,$this->_highlight_range}#sui", cutHtmlText($row[preg_replace("#.*?\.#", "", $f['field'])], 50000000, '', true, false, true), $matches)) {
                                                        $res[$i][$f['field']] = preg_replace("#".$rexp."#i", "<span class=\"evidence\">$0</span>", $matches[0]);
                                                }
                                                else $res[$i][$f['field']] = '';
                                        }
                                        else $res[$i][$f] = $row[preg_replace("#.*?\.#", "", $f)];
                                }
                                $i++;
                        }
                }

                return $res;
        
        }


}

?>