Add some functions in games.php file but they are not working yet

blokus.php

@@ -139,6 +139,9 @@ public function routeRequest($input) {
 //     }
 // });
 
+//games functions
+
+
 // Handle the request
 $input = json_decode(file_get_contents('php://input'), true);
 $router->routeRequest($input);

lib/games.php

@@ -0,0 +1,84 @@
+<?php
+
+require_once 'dbconnect.php';
+require_once 'helper.php';
+
+header('Content-Type: application/json');
+
+function getNextPlayerTurn($gameId) {
+    global $pdo;
+
+    $sql = "SELECT current_turn FROM games WHERE game_id = ?";
+    $stmt = $pdo->prepare($sql);
+    $stmt->execute([$gameId]);
+    $currentTurn = $stmt->fetchColumn();
+
+    if ($currentTurn !== false) {
+        $sql = "SELECT user_id FROM game_players WHERE game_id = ? ORDER BY player_order";
+        $stmt = $pdo->prepare($sql);
+        $stmt->execute([$gameId]);
+        $players = $stmt->fetchAll(PDO::FETCH_COLUMN);
+
+        $currentIndex = array_search ($currentTurn, $players);
+        $nextIndex = ($currentIndex + 1) % count($players);
+
+        return $players[$nextIndex]; 
+    }
+
+    return null; 
+}
+
+function getAvailableMoves($gameId, $playerId) {
+    global $pdo;
+
+    $sql = "SELECT board_state FROM games WHERE game_id = ?";
+    $stmt = $pdo->prepare($sql);
+    $stmt->execute([$gameId]);
+    $boardState = $stmt->fetchColumn();
+
+    $sql = "SELECT piece_id FROM player_pieces WHERE game_id = ? AND player_id = ? AND is_used = 0";
+    $stmt = $pdo->prepare($sql);
+    $stmt->execute([$gameId, $playerId]);
+    $availablePieces = $stmt->fetchAll(PDO::FETCH_COLUMN);
+
+    $availableMoves = [
+        'placeholder' => 'Implement game rules to calculate moves'
+    ];
+
+    return $availableMoves;
+}
+
+function getPlayerPieces($gameId, $playerId) {
+    global $pdo;
+
+    $sql = "SELECT piece_id FROM player_pieces WHERE game_id = ? AND player_id = ? AND is_used = 0";
+    $stmt = $pdo->prepare($sql);
+    $stmt->execute([$gameId, $playerId]);
+
+    return $stmt->fetchAll(PDO::FETCH_COLUMN);
+}
+
+function updatePlayerMove($gameId, $playerId, $move) {
+    global $pdo;
+
+    $pdo->beginTransaction();
+
+    try {
+        $sql = "UPDATE games SET board_state = ?, current_turn = ? WHERE game_id = ?";
+        $stmt = $pdo->prepare($sql);
+        $newBoardState = json_encode($move['boardState']); 
+        $stmt->execute([$newBoardState, $move['nextPlayer'], $gameId]);
+
+        $sql = "UPDATE player_pieces SET is_used = 1 WHERE game_id = ? AND player_id = ? AND piece_id = ?";
+        $stmt = $pdo->prepare($sql);
+        $stmt->execute([$gameId, $playerId, $move['pieceId']]);
+
+        $pdo->commit();
+
+        return true;
+    } catch (Exception $e) {
+        $pdo->rollBack();
+        return false;
+    }
+}
+?>