Fix using SQLite as a database engine

- The ‘sqlite_*’ functions don't exist anymore in PHP 8. They have been replaced
  with several ‘SQLite3*’ classes.

- There are some differences between MySQL and SQLite queries that showed up
  while doing this work. These differences have been pushed into a QueryBuilder
  class so that the other database engines don't have to be modified. This is
  done in an ad-hoc basis for now, just to get things working.

- SQLite doesn't support the ‘!’ negation operator used as ‘!ISNULL(...)’,
  instead I use ‘IIF(...)’.

- SQLite doesn't support a ‘LEFT(...)’ function, instead I use ‘SUBSTRING(...,
  0, ...)’.

- The SQLite3 module doesn't provide a connection identifier, instead you use an
  object that represents the connection.

- SQLite doesn't support the ‘ALL’ keyword (or at least doesn't support it in
  the same way MySQL does). Instead of ‘<> ALL <subquery>’ I use ‘NOT IN
  <subquery>’.

- The ‘SQLite3*’ classes don't provide any way to determine how many rows have
  been returned without iterating through all of them, so any place that tries
  to figure out the rows beforehand just doesn't anymore.

- All the database engine classes require a ‘QueryBuilder’ instance. The sqlite
  one uses a specialized one. I can't test most of these database engines, so
  I'm focusing on SQLite and MySQL/MariaDB for now.

1 files changed, 73 insertions, 43 deletions

diff --git a/src/SemanticScuttle/db/sqlite.php b/src/SemanticScuttle/db/sqlite.php
index 940e194..49de59c 100644
--- a/src/SemanticScuttle/db/sqlite.php
+++ b/src/SemanticScuttle/db/sqlite.php
@@ -1,10 +1,10 @@
 <?php
-/** 
+/**
 *
 * @package dbal_sqlite
 * @version $Id: sqlite.php,v 1.2 2005/06/10 08:52:03 devalley Exp $
-* @copyright (c) 2005 phpBB Group 
-* @license http://opensource.org/licenses/gpl-license.php GNU Public License 
+* @copyright (c) 2005 phpBB Group
+* @license http://opensource.org/licenses/gpl-license.php GNU Public License
 *
 */
 
@@ -16,13 +16,15 @@ if (!defined("SQL_LAYER"))
 
 define("SQL_LAYER","sqlite");
 
+require_once 'sqlite.querybuilder.php';
+
 /**
 * @package dbal_sqlite
 * Sqlite Database Abstraction Layer
 */
 class sql_db
 {
-	var $db_connect_id;
+    var $db_connection;
 	var $query_result;
 	var $return_on_error = false;
 	var $transaction = false;
@@ -38,6 +40,13 @@ class sql_db
 	var $server;
 	/*2023-12-20 end */
 
+    public $QueryBuilder;
+
+    public function __construct()
+    {
+         $this->QueryBuilder = new SQLiteQueryBuilder(); 
+    }
+
 	function sql_connect($sqlserver, $sqluser, $sqlpassword, $database, $port, $persistency = false)
 	{
 		$this->persistency = $persistency;
@@ -45,20 +54,20 @@ class sql_db
 		$this->server = $sqlserver . (($port) ? ':' . $port : '');
 		$this->dbname = $database;
 
-		$this->db_connect_id = ($this->persistency) ? @sqlite_popen($this->server, 0, $error) : @sqlite_open($this->server, 0, $error);
+		$this->db_connection = ($this->persistency) ? @sqlite_popen($this->server, 0, $error) : new SQLite3($this->server);
 
-		return ($this->db_connect_id) ? true : $error;
+		return ($this->db_connection) ? true : $error;
 	}
 
 	// Other base methods
 	function sql_close()
 	{
-		if (!$this->db_connect_id)
+		if (!$this->db_connection)
 		{
 			return false;
 		}
 
-		return @sqlite_close($this->db_connect_id);
+		return $this->db_connection->close();
 	}
 
 	function sql_return_on_error($fail = false)
@@ -77,17 +86,17 @@ class sql_db
 		{
 			case 'begin':
 				$this->transaction = true;
-				$result = @sqlite_query('BEGIN', $this->db_connect_id);
+				$result = $this->db_connection->query('BEGIN');
 				break;
 
 			case 'commit':
 				$this->transaction = false;
-				$result = @sqlite_query('COMMIT', $this->db_connect_id);
+				$result = $this->db_connection->query('COMMIT');
 				break;
 
 			case 'rollback':
 				$this->transaction = false;
-				$result = @sqlite_query('ROLLBACK', $this->db_connect_id);
+				$result = $this->db_connection->query('ROLLBACK');
 				break;
 
 			default:
@@ -98,7 +107,7 @@ class sql_db
 	}
 
 	// Base query method
-	function sql_query($query = '', $expire_time = 0)
+	function sql_query($query = '', $cache_ttl = 0)
 	{
 		if ($query != '')
 		{
@@ -124,7 +133,7 @@ class sql_db
 					$curtime = $curtime[0] + $curtime[1] - $starttime;
 				}
 
-				if (!($this->query_result = @sqlite_query($query, $this->db_connect_id)))
+				if (!($this->query_result = $this->db_connection->query($query)))
 				{
 					$this->sql_error($query);
 				}
@@ -151,9 +160,9 @@ class sql_db
 					if (preg_match('#^SELECT#', $query))
 					{
 						$html_table = FALSE;
-						if ($result = @sqlite_query("EXPLAIN $query", $this->db_connect_id))
+						if ($result = $this->db_connection->query("EXPLAIN $query"))
 						{
-							while ($row = @sqlite_fetch_array($result, @sqlite_ASSOC))
+							while ($row = $result->fetchArray(SQLITE_ASSOC))
 							{
 								if (!$html_table && sizeof($row))
 								{
@@ -261,6 +270,25 @@ class sql_db
 			}
 			$query = implode(', ', $values);
 		}
+        else if ($query == 'SELECT')
+        {
+			foreach ($assoc_ary as $key => $var)
+			{
+				if (is_null($var))
+				{
+					$values[] = "$key = NULL";
+				}
+				elseif (is_string($var))
+				{
+					$values[] = "$key = '" . $this->sql_escape($var) . "'";
+				}
+				else
+				{
+					$values[] = (is_bool($var)) ? "$key = " . intval($var) : "$key = $var";
+				}
+			}
+			$query = implode(' AND ', $values);
+        }
 
 		return $query;
 	}
@@ -271,50 +299,46 @@ class sql_db
 	//         don't want this here by a middle Milestone
 	function sql_numrows($query_id = false)
 	{
-		if (!$query_id)
-		{
-			$query_id = $this->query_result;
-		}
-
-		return ($query_id) ? @sqlite_num_rows($query_id) : false;
+        // The new SQLite3 module in PHP doesn't provide a way of determining
+        // the number of rows returned before iterating through them.
+		throw new Exception('Not Implemented');
 	}
 
 	function sql_affectedrows()
 	{
-		return ($this->db_connect_id) ? @sqlite_changes($this->db_connect_id) : false;
+		return ($this->db_connection) ? $this->db_connection->changes() : false;
 	}
 
-	function sql_fetchrow($query_id = 0)
+	function sql_fetchrow($query_result = NULL)
 	{
 		global $cache;
 
-		if (!$query_id)
+		if (!$query_result)
 		{
-			$query_id = $this->query_result;
+			$query_result = $this->query_result;
 		}
 
-		if ($cache->sql_exists($query_id))
+		if (isset($cache->sql_rowset[$query_result]))
 		{
-			return $cache->sql_fetchrow($query_id);
+			return $cache->sql_fetchrow($query_result);
 		}
 
-		return ($query_id) ? @sqlite_fetch_array($query_id, @sqlite_ASSOC) : false;
+		return ($query_result) ? $query_result->fetchArray(SQLITE3_ASSOC) : false;
 	}
 
-	function sql_fetchrowset($query_id = 0)
+	function sql_fetchrowset($query_result = false)
 	{
-		if (!$query_id)
+		if (!$query_result)
 		{
-			$query_id = $this->query_result;
+			$query_result = $this->query_result;
 		}
 
-		if ($query_id)
+		if ($query_result)
 		{
-			unset($this->rowset[$query_id]);
-			unset($this->row[$query_id]);
-			while ($this->rowset[$query_id] = @sqlite_fetch_array($query_id, @sqlite_ASSOC))
+            $result = array();
+			while ($row = $query_result->fetchArray(SQLITE3_ASSOC))
 			{
-				$result[] = $this->rowset[$query_id];
+				$result[] = $row;
 			}
 			return $result;
 		}
@@ -331,9 +355,15 @@ class sql_db
 			$query_id = $this->query_result;
 		}
 
-		if ($query_id)
+        $row = [];
+
+        while ($rownum > 0) {
+            $row = $query_id->fetchArray(SQLITE3_NUM);
+        }
+
+		if ($row)
 		{
-			return ($rownum > -1) ? ((@sqlite_seek($query_id, $rownum)) ? @sqlite_column($query_id, $field) : false) : @sqlite_column($query_id, $field);
+			return $row[$field];
 		}
 	}
 
@@ -349,7 +379,7 @@ class sql_db
 
 	function sql_nextid()
 	{
-		return ($this->db_connect_id) ? @sqlite_last_insert_rowid($this->db_connect_id) : false;
+		return ($this->db_connection) ? $this->db_connection->lastInsertRowID() : false;
 	}
 
 	function sql_freeresult($query_id = false)
@@ -359,7 +389,7 @@ class sql_db
 
 	function sql_escape($msg)
 	{
-		return @sqlite_escape_string(stripslashes($msg));
+		return SQLite3::escapeString(stripslashes($msg));
 	}
 
 	function sql_error($sql = '')
@@ -369,7 +399,7 @@ class sql_db
 			$this_page = (!empty($_SERVER['PHP_SELF'])) ? $_SERVER['PHP_SELF'] : $_ENV['PHP_SELF'];
 			$this_page .= '&' . ((!empty($_SERVER['QUERY_STRING'])) ? $_SERVER['QUERY_STRING'] : $_ENV['QUERY_STRING']);
 
-			$message = '<u>SQL ERROR</u> [ ' . SQL_LAYER . ' ]<br /><br />' . @sqlite_error_string(@sqlite_last_error($this->db_connect_id)) . '<br /><br /><u>CALLING PAGE</u><br /><br />'  . htmlspecialchars($this_page) . (($sql != '') ? '<br /><br /><u>SQL</u><br /><br />' . $sql : '') . '<br />';
+			$message = '<u>SQL ERROR</u> [ ' . SQL_LAYER . ' ]<br /><br />' . $this->db_connection->lastErrorMsg() . '<br /><br /><u>CALLING PAGE</u><br /><br />'  . htmlspecialchars($this_page) . (($sql != '') ? '<br /><br /><u>SQL</u><br /><br />' . $sql : '') . '<br />';
 
 			if ($this->transaction)
 			{
@@ -380,8 +410,8 @@ class sql_db
 		}
 
 		$result = array(
-			'message'	=> @sqlite_error_string(@sqlite_last_error($this->db_connect_id)),
-			'code'		=> @sqlite_last_error($this->db_connect_id)
+			'message'	=> $this->db_connection->lastErrorMsg(),
+			'code'		=> $this->db_connection->lastErrorCode(),
 		);
 
 		return $result;