feat: instrument model

backend/routers/instrument_models.py

@@ -37,6 +37,7 @@ class VirtualEvent(BaseModel):
 class WhatIfBody(BaseModel):
     period: str = "1y"
     virtual_events: List[VirtualEvent] = []
+    start_date: Optional[str] = None
 
 
 class CalibrateBody(BaseModel):
@@ -192,10 +193,26 @@ def get_price_history(
         conn.close()
 
 
+def _ph_period(start_date: Optional[str], fallback_period: str) -> str:
+    """Compute the price-history period string needed to cover start_date → today."""
+    if not start_date:
+        return fallback_period
+    try:
+        from datetime import datetime as _dt
+        days = (_dt.utcnow().date() - _dt.fromisoformat(start_date[:10]).date()).days + 10
+        for p, d in [("5d", 7), ("1mo", 35), ("3mo", 95), ("6mo", 190), ("1y", 370), ("2y", 740)]:
+            if days <= d:
+                return p
+        return "2y"
+    except Exception:
+        return fallback_period
+
+
 @router.get("/{instrument}/timeline")
 def get_instrument_timeline(
     instrument: str,
-    period: str = Query("1y", description="5d|1mo|3mo|6mo|1y|2y"),
+    period:     str           = Query("1y",  description="5d|1mo|3mo|6mo|1y|2y"),
+    start_date: Optional[str] = Query(None,  description="Date de début ISO (override period)"),
 ) -> List[Dict[str, Any]]:
     """Simulation jour par jour de tous les nœuds du modèle sur la période."""
     from services.database import get_conn
@@ -203,9 +220,8 @@ def get_instrument_timeline(
     from services.price_history import get_price_history
     conn = get_conn()
     try:
-        # Pré-peupler le cache prix pour que l'auto-anchor ait les données disponibles
-        get_price_history(conn, instrument.upper(), period)
-        data = simulate_timeline(conn, instrument.upper(), period)
+        get_price_history(conn, instrument.upper(), _ph_period(start_date, period))
+        data = simulate_timeline(conn, instrument.upper(), period, start_date=start_date)
         if not data:
             raise HTTPException(status_code=404, detail=f"Modèle introuvable pour {instrument.upper()}")
         return data
@@ -224,10 +240,12 @@ def timeline_whatif(
     from services.price_history import get_price_history
     conn = get_conn()
     try:
-        # Garantir que le cache prix est disponible pour l'auto-anchor
-        get_price_history(conn, instrument.upper(), body.period)
+        get_price_history(conn, instrument.upper(), _ph_period(body.start_date, body.period))
         ve_list = [ve.dict() for ve in body.virtual_events]
-        data = simulate_timeline(conn, instrument.upper(), body.period, virtual_events=ve_list)
+        data = simulate_timeline(
+            conn, instrument.upper(), body.period,
+            virtual_events=ve_list, start_date=body.start_date
+        )
         if not data:
             raise HTTPException(status_code=404, detail=f"Modèle introuvable pour {instrument.upper()}")
         return data