fixed the manipulation for the FIELD() function with column name

git-svn-id: https://plugins.svn.wordpress.org/sqlite-integration/trunk@949333 b8457f37-d9ea-0310-8a92-e5e31aec5664

functions-5-2.php

@@ -478,14 +478,21 @@ class PDOSQLiteUDFS {
 	 * @return unsigned integer
 	 */
 	public function field() {
+		global $wpdb;
 		$numArgs = func_num_args();
 		if ($numArgs < 2 or is_null(func_get_arg(0))) {
 			return 0;
+		} else {
+			$arg_list = func_get_args();
 		}
-		$arr = func_get_args();
+		$searchString = array_shift($arg_list);
-		$searchString = strtolower(array_shift($arr));
+		$str_to_check = substr($searchString, 0, strpos($searchString, '.'));
+		$str_to_check = str_replace($wpdb->prefix, '', $str_to_check);
+		if ($str_to_check && in_array(trim($str_to_check), $wpdb->tables)) return;
 		for ($i = 0; $i < $numArgs-1; $i++) {
-			if ($searchString === strtolower($arr[$i])) return $i + 1;
+			if ($searchString === strtolower($arg_list[$i])) {
+				return $i + 1;
+			}
 		}
 		return 0;
 	}

functions.php

@@ -442,6 +442,7 @@ class PDOSQLiteUDFS {
 	 * @return unsigned integer
 	 */
 	public function field() {
+		global $wpdb;
 		$numArgs = func_num_args();
 		if ($numArgs < 2 or is_null(func_get_arg(0))) {
 			return 0;
@@ -449,6 +450,9 @@ class PDOSQLiteUDFS {
 			$arg_list = func_get_args();
 		}
 		$searchString = array_shift($arg_list);
+		$str_to_check = substr($searchString, 0, strpos($searchString, '.'));
+		$str_to_check = str_replace($wpdb->prefix, '', $str_to_check);
+		if ($str_to_check && in_array(trim($str_to_check), $wpdb->tables)) return;
 		for ($i = 0; $i < $numArgs-1; $i++) {
 			if ($searchString === strtolower($arg_list[$i])) {
 				return $i + 1;

pdoengine.class.php

@@ -26,6 +26,12 @@ class PDOEngine extends PDO {
 	 * @var unsigned integer
 	 */
 	public  $found_rows_result = null;
+	/**
+	 * Class variable used for query with ORDER BY FIELD()
+	 *
+	 * @var array of the object
+	 */
+	public $pre_ordered_results = null;
 	/**
 	 * Class variable to store the rewritten queries.
 	 *
@@ -370,6 +376,12 @@ class PDOEngine extends PDO {
 			default:
 				$engine = $this->prepare_engine($this->query_type);
 				$this->rewritten_query = $engine->rewrite_query($query, $this->query_type);
+				if (!is_null($this->pre_ordered_results)) {
+					$this->results = $this->pre_ordered_results;
+					$this->num_rows = $this->return_value = count($this->results);
+					$this->pre_ordered_results = null;
+					break;
+				}
 				$this->queries[]       = "Rewritten:\n$this->rewritten_query";
 				$this->extract_variables();
 				$statement = $this->prepare_query();

query.class.php

@@ -54,6 +54,12 @@ class PDOSQLiteDriver {
 	 * @var integer
 	 */
 	private $num_of_rewrite_between = 0;
+	/**
+	 * Variable to check order by field() with column data.
+	 *
+	 * @var boolean
+	 */
+	private $orderby_field = false;
 	/**
 	 * Method to rewrite a query string for SQLite to execute.
 	 *
@@ -97,6 +103,7 @@ class PDOSQLiteDriver {
 				//$this->rewrite_boolean();
 				$this->fix_date_quoting();
 				$this->rewrite_between();
+				$this->handle_orderby_field();
 				break;
 			case 'insert':
 				//$this->safe_strip_backticks();
@@ -192,6 +199,9 @@ class PDOSQLiteDriver {
 						$this->rewrite_between = true;
 						$this->num_of_rewrite_between++;
 					}
+					if (stripos($token, 'ORDER BY FIELD') !== false) {
+						$this->orderby_field = true;
+					}
 				}
 			}
 			$query_string .= $token;
@@ -726,6 +736,45 @@ class PDOSQLiteDriver {
 			$this->num_of_rewrite_between--;
 		} while ($this->num_of_rewrite_between > 0);
 	}
+	/**
+	 * Method to handle ORDER BY FIELD() clause.
+	 *
+	 * When FIELD() function has column name to compare, we can't rewrite it with
+	 * use defined functions. When this function detect column name in the argument,
+	 * it creates another instance, does the query withuot ORDER BY clause and gives
+	 * the result array sorted to the main instance.
+	 *
+	 * If FIELD() function doesn't have column name, it will use the user defined
+	 * function. usort() function closure function to compare the items.
+	 *
+	 * @access private
+	 */
+	private function handle_orderby_field() {
+		if (!$this->orderby_field) return;
+		global $wpdb;
+		$pattern = '/\\s+ORDER\\s+BY\\s+FIELD\\s*\(\\s*([^\)]+?)\\s*\)/i';
+		if (preg_match($pattern, $this->_query, $match)) {
+			global $flipped;
+			$params   = explode(',', $match[1]);
+			$params   = array_map('trim', $params);
+			$tbl_col  = array_shift($params);
+			$flipped  = array_flip($params);
+			$tbl_name = substr($tbl_col, 0, strpos($tbl_col, '.'));
+			$tbl_name = str_replace($wpdb->prefix, '', $tbl_name);
+			if ($tbl_name && in_array($tbl_name, $wpdb->tables)) {
+				$query = str_replace($match[0], '', $this->_query);
+				$_wpdb = new PDODB();
+				$results = $_wpdb->get_results($query);
+				$_wpdb = null;
+				$compare = function($a, $b) {
+					global $flipped;
+					return $flipped[$a->ID] - $flipped[$b->ID];
+				};
+				usort($results, $compare);
+			}
+			$wpdb->dbh->pre_ordered_results = $results;
+		}
+	}
 	/**
 	 * Method to avoid DELETE with JOIN statement.
 	 *