*
* - filetype - string, type of searched files,
* meaningful values: 'audioclip', 'playlist'
* - operator - string, type of conditions join
* (any condition matches / all conditions match),
* meaningful values: 'and', 'or', ''
* (may be empty or ommited only with less then 2 items in
* "conditions" field)
*
* - conditions - array of hashes with structure:
*
* - cat - string, metadata category name
* - op - string, operator - meaningful values:
* 'full', 'partial', 'prefix', '=', '<',
* '<=', '>', '>='
* - val - string, search value
*
*
*
*
* Format of search/browse results: hash, with following structure:
*
* - results : array of gunids have found
* - cnt : integer - number of matching items
*
*
* @see MetaData
* @see StoredFile
*/
class DataEngine{
/**
* Constructor
*
* @param gb reference to BasicStor object
* @return this
*/
function DataEngine(&$gb)
{
$this->gb =& $gb;
$this->dbc =& $gb->dbc;
$this->mdataTable = $gb->mdataTable;
$this->filesTable = $gb->filesTable;
$this->filetypes =
array('audioclip'=>'audioclip', 'playlist'=>'playlist');
}
/**
* Method returning array with where-parts of sql queries
*
* @param conditions array - see conditions field in search criteria format
* definition in DataEngine class documentation
* @return array of strings - where-parts of SQL qyeries
*/
function _makeWhereArr($conditions)
{
$ops = array('full'=>"='%s'", 'partial'=>"like '%%%s%%'", 'prefix'=>"like '%s%%'",
'<'=>"< '%s'", '='=>"= '%s'", '>'=>"> '%s'", '<='=>"<= '%s'", '>='=>">= '%s'"
);
$whereArr = array();
if(is_array($conditions)){
foreach($conditions as $cond){
$catQn = strtolower($cond['cat']);
$op = strtolower($cond['op']);
$value = strtolower($cond['val']);
$splittedQn = XML_Util::splitQualifiedName($catQn);
$catNs = $splittedQn['namespace'];
$cat = $splittedQn['localPart'];
$opVal = sprintf($ops[$op], addslashes($value));
// escape % for sprintf in whereArr construction:
$cat = str_replace("%", "%%", $cat);
$opVal = str_replace("%", "%%", $opVal);
$sqlCond =
" %s.predicate = '{$cat}' AND".
" %s.objns='_L' AND lower(%s.object) {$opVal}\n";
if(!is_null($catNs)){
$catNs = str_replace("%", "%%", $catNs);
$sqlCond = " %s.predns = '{$catNs}' AND $sqlCond";
}
$whereArr[] = $sqlCond;
}
}
return $whereArr;
}
/**
* Method returning SQL query for search/browse with AND operator
* (without using INTERSECT command)
*
* @param fldsPart string - fields part of sql query
* @param whereArr array - array of where-parts
* @param fileCond string - condition for files table
* @param browse boolean - true if browse vals required instead of gunids
* @param brFldNs string - namespace prefix of category for browse
* @param brFld string - category for browse
* @return query string
*/
function _makeAndSqlWoIntersect($fldsPart, $whereArr, $fileCond, $browse,
$brFldNs=NULL, $brFld=NULL)
{
$innerBlocks = array();
foreach($whereArr as $i=>$v){
$whereArr[$i] = sprintf($v, "md$i", "md$i", "md$i", "md$i");
$lastTbl = ($i==0 ? "f" : "md".($i-1));
$innerBlocks[] =
"INNER JOIN {$this->mdataTable} md$i ON md$i.gunid = $lastTbl.gunid\n";
}
// query construcion:
$sql = "SELECT $fldsPart\nFROM {$this->filesTable} f\n".join("", $innerBlocks);
if($browse){
$sql .= "INNER JOIN {$this->mdataTable} br".
"\n ON br.gunid = f.gunid AND br.objns='_L' AND br.predicate='{$brFld}'";
if(!is_null($brFldNs)) $sql .= " AND br.predns='{$brFldNs}'";
$sql .= "\n";
}
if(!is_null($fileCond)) $whereArr[] = " $fileCond";
if(count($whereArr)>0) $sql .= "WHERE\n".join(" AND\n", $whereArr);
if($browse) $sql .= "\nORDER BY br.object";
return $sql;
}
/**
* Method returning SQL query for search/browse with AND operator
* (using INTERSECT command)
*
* @param fldsPart string - fields part of sql query
* @param whereArr array - array of where-parts
* @param fileCond string - condition for files table
* @param browse boolean - true if browse vals required instead of gunids
* @param brFldNs string - namespace prefix of category for browse
* @param brFld string - category for browse
* @return query string
*/
function _makeAndSql($fldsPart, $whereArr, $fileCond, $browse,
$brFldNs=NULL, $brFld=NULL)
{
if(!USE_INTERSECT) return $this->_makeAndSqlWoIntersect(
$fldsPart, $whereArr, $fileCond, $browse, $brFldNs, $brFld);
$isectBlocks = array();
foreach($whereArr as $i=>$v){
$whereArr[$i] = sprintf($v, "md$i", "md$i", "md$i", "md$i");
$isectBlocks[] =
" SELECT gunid FROM {$this->mdataTable} md$i\n".
" WHERE\n {$whereArr[$i]}";
}
// query construcion:
if(count($isectBlocks)>0){
$isectBlock =
"FROM\n(\n".join("INTERSECT\n", $isectBlocks).") sq\n".
"INNER JOIN {$this->filesTable} f ON f.gunid = sq.gunid";
}else{
$isectBlock = "FROM {$this->filesTable} f";
}
$sql =
"SELECT $fldsPart\n".$isectBlock;
if($browse){
$sql .= "\nINNER JOIN {$this->mdataTable} br ON br.gunid = f.gunid\n".
"WHERE br.objns='_L' AND br.predicate='{$brFld}'";
if(!is_null($brFldNs)) $sql .= " AND br.predns='{$brFldNs}'";
$glue = " AND";
}else{ $glue = "WHERE";}
if(!is_null($fileCond)) $sql .= "\n$glue $fileCond";
if($browse) $sql .= "\nORDER BY br.object";
return $sql;
}
/**
* Method returning SQL query for search/browse with OR operator
*
* @param fldsPart string - fields part of sql query
* @param whereArr array - array of where-parts
* @param fileCond string - condition for files table
* @param browse boolean - true if browse vals required instead of gunids
* @param brFldNs string - namespace prefix of category for browse
* @param brFld string - category for browse
* @return query string
*/
function _makeOrSql($fldsPart, $whereArr, $fileCond, $browse,
$brFldNs=NULL, $brFld=NULL)
{
$whereArr[] = " FALSE\n";
foreach($whereArr as $i=>$v){
$whereArr[$i] = sprintf($v, "md", "md", "md", "md");
}
// query construcion:
$sql = "SELECT $fldsPart\nFROM {$this->filesTable} f\n";
if($browse){
$sql .= "INNER JOIN {$this->mdataTable} br".
"\n ON br.gunid = f.gunid AND br.objns='_L' AND br.predicate='{$brFld}'";
if(!is_null($brFldNs)) $sql .= " AND br.predns='{$brFldNs}'";
$sql .= "\n";
}
if(count($whereArr)>0){
$sql .= "INNER JOIN {$this->mdataTable} md ON md.gunid=f.gunid\n";
$sql .= "WHERE\n(\n".join(" OR\n", $whereArr).")";
$glue = " AND";
}else{ $glue = "WHERE"; }
if(!is_null($fileCond)) $sql .= "$glue $fileCond";
if($browse) $sql .= "\nORDER BY br.object";
return $sql;
}
/**
* Search in local metadata database.
*
* @param cri hash, search criteria see DataEngine class documentation
* @param limit int, limit for result arrays (0 means unlimited)
* @param offset int, starting point (0 means without offset)
* @return hash, fields:
* results : array with gunid strings
* cnt : integer - number of matching gunids
* of files have been found
*/
function localSearch($cri, $limit=0, $offset=0)
{
$res = $this->_localGenSearch($cri, $limit, $offset);
// if(PEAR::isError($res)) return $res;
return $res;
}
/**
* Search in local metadata database, more general version.
*
* @param criteria hash, search criteria see DataEngine class documentation
* @param limit int, limit for result arrays (0 means unlimited)
* @param offset int, starting point (0 means without offset)
* @param brFldNs string - namespace prefix of category for browse
* @param brFld string, metadata category identifier for browse
* @return hash, fields:
* results : array with gunid strings
* cnt : integer - number of matching gunids
* of files have been found
*/
function _localGenSearch($criteria, $limit=0, $offset=0,
$brFldNs=NULL, $brFld=NULL)
{
$filetype = $this->filetypes[strtolower($criteria['filetype'])];
# if(is_null($filetype)) $filetype =
$operator = strtolower($criteria['operator']);
$whereArr = $this->_makeWhereArr($criteria['conditions']);
$browse = !is_null($brFld);
if(!$browse){
$fldsPart = "DISTINCT to_hex(f.gunid)as gunid";
}else{
$fldsPart = "DISTINCT br.object";
}
$limitPart = ($limit != 0 ? " LIMIT $limit" : '' ).
($offset != 0 ? " OFFSET $offset" : '' );
$fileCond = "f.state='ready'";
if(!is_null($filetype)) $fileCond .= " AND f.ftype='$filetype'";
if($operator == 'and'){ // operator: and
$sql = $this->_makeAndSql(
$fldsPart, $whereArr, $fileCond, $browse, $brFldNs, $brFld);
}else{ // operator: or
$sql = $this->_makeOrSql(
$fldsPart, $whereArr, $fileCond, $browse, $brFldNs, $brFld);
}
// echo "\n---\n$sql\n---\n";
$cnt = $this->_getNumRows($sql);
if(PEAR::isError($cnt)) return $cnt;
$res = $this->dbc->getCol($sql.$limitPart);
if(PEAR::isError($res)) return $res;
if(!is_array($res)) $res = array();
if(!$browse){
$res = array_map(array("StoredFile", "_normalizeGunid"), $res);
}
return array('results'=>$res, 'cnt'=>$cnt);
}
/**
* Return values of specified metadata category
*
* @param category string, metadata category name
* with or without namespace prefix (dc:title, author)
* @param limit int, limit for result arrays (0 means unlimited)
* @param offset int, starting point (0 means without offset)
* @param criteria hash
* @return hash, fields:
* results : array with gunid strings
* cnt : integer - number of matching values
*/
function browseCategory($category, $limit=0, $offset=0, $criteria=NULL)
{
$category = strtolower($category);
$r = XML_Util::splitQualifiedName($category);
$catNs = $r['namespace'];
$cat = $r['localPart'];
if(is_array($criteria) && count($criteria)>0){
return $this->_localGenSearch($criteria, $limit, $offset, $catNs, $cat);
}
$sqlCond = "m.predicate='$cat' AND m.objns='_L'";
if(!is_null($catNs)){
$sqlCond = "m.predns = '{$catNs}' AND $sqlCond";
}
$limitPart = ($limit != 0 ? " LIMIT $limit" : '' ).
($offset != 0 ? " OFFSET $offset" : '' );
$sql =
"SELECT DISTINCT m.object FROM {$this->mdataTable} m\n".
"WHERE $sqlCond";
// echo "\n---\n$sql\n---\n";
$cnt = $this->_getNumRows($sql);
if(PEAR::isError($cnt)) return $cnt;
$res = $this->dbc->getCol($sql.$limitPart);
if(PEAR::isError($res)) return $res;
if(!is_array($res)) $res = array();
return array('results'=>$res, 'cnt'=>$cnt);
}
/**
* Get number of rows in query result
*
* @param query string, sql query
* @return int, number of rows in query result
*/
function _getNumRows($query)
{
$rh = $this->dbc->query($query);
if(PEAR::isError($rh)) return $rh;
$cnt = $rh->numRows();
if(PEAR::isError($cnt)) return $cnt;
$rh->free();
return $cnt;
}
}
?>