docs: update backtesting research, optimizer, ADX and visual analysis

src/data/fetcher.py

@@ -1,5 +1,4 @@
 # src/data/fetcher.py
-# src/data/fetcher.py
 """
 Módulo para obtener datos de exchanges usando CCXT
 """
@@ -110,7 +109,9 @@ class DataFetcher:
         self,
         symbol: str,
         timeframe: str = '1h',
-        days: int = 30,
+        since: Optional[datetime] = None,
+        until: Optional[datetime] = None,
+        days: Optional[int] = None,
         max_retries: int = 3
     ) -> pd.DataFrame:
         """
@@ -126,7 +127,13 @@ class DataFetcher:
             DataFrame con todos los datos históricos
         """
         all_data = []
-        since = datetime.now() - timedelta(days=days)
+        if since is None:
+            if days is None:
+                raise ValueError("Debes proporcionar 'since' o 'days'")
+            since = datetime.utcnow() - timedelta(days=days)
+
+        if until is None:
+            until = datetime.utcnow()
         
         log.info(f"Iniciando descarga histórica: {symbol} desde {since.date()}")
         
@@ -151,7 +158,8 @@ class DataFetcher:
                     
                     # Actualizar 'since' al último timestamp + 1
                     last_timestamp = df.index[-1]
-                    since = last_timestamp + pd.Timedelta(seconds=1)
+                    timeframe_seconds = self.exchange.parse_timeframe(timeframe)
+                    since = last_timestamp + pd.Timedelta(seconds=timeframe_seconds)
                     
                     # Verificar si ya llegamos al presente
                     if since >= datetime.now():