enhancing backtesting functionality

backend/indicators/sessions.py

@@ -1,5 +1,6 @@
 from datetime import time
 
+# EST sessions (for histdata CSVs)
 SESSIONS_EST = {
     "asian": (time(19, 0), time(3, 0)),
     "london": (time(2, 0), time(5, 0)),
@@ -8,25 +9,42 @@ SESSIONS_EST = {
     "london_ny_overlap": (time(8, 0), time(10, 0)),
 }
 
+# UTC+2 sessions (for MetaTrader exported CSVs)
+SESSIONS_MT5 = {
+    "asian": (time(2, 0), time(10, 0)),
+    "london": (time(9, 0), time(12, 0)),
+    "new_york": (time(14, 0), time(17, 0)),
+    "london_close": (time(17, 0), time(19, 0)),
+    "london_ny_overlap": (time(15, 0), time(17, 0)),
+}
+
+# Active session map (switch based on data source)
+_active_sessions = SESSIONS_EST
+
+
+def set_timezone(tz="est"):
+    global _active_sessions
+    if tz.lower() in ("mt5", "utc+2", "server"):
+        _active_sessions = SESSIONS_MT5
+    else:
+        _active_sessions = SESSIONS_EST
+
 
 def in_session(candle_time, session_name):
     if session_name == "all":
         return True
-
-    if session_name not in SESSIONS_EST:
+    if session_name not in _active_sessions:
         return True
 
     t = candle_time.time()
-    start, end = SESSIONS_EST[session_name]
+    start, end = _active_sessions[session_name]
     if start > end:
         return t >= start or t < end
     return start <= t < end
 
 
 def get_session(candle_time):
-    for name in SESSIONS_EST:
-        if name == "all":
-            continue
+    for name in _active_sessions:
         if in_session(candle_time, name):
             return name
     return "off_hours"