Add Binance SIM market adapter and exchange switch in settings.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/api/settings.py

@@ -6,6 +6,12 @@ from fastapi import APIRouter, Depends, HTTPException
 from pydantic import BaseModel, Field
 
 from ..config import get_settings
+from ..exchange.runtime import (
+    load_runtime_settings,
+    normalize_exchange_name,
+    persist_exchange_choice,
+    reload_market_session,
+)
 from ..models.db import get_db
 from ..sim.ledger import Ledger
 from ..sim.matcher import Matcher
@@ -46,6 +52,7 @@ class StrategySettingsBody(BaseModel):
     close_bid_mark_max_pct: float | None = Field(default=None, ge=1, le=100)
     perp_qty_eth: float | None = Field(default=None, ge=0.01, le=100)
     option_qty_eth: float | None = Field(default=None, ge=0.01, le=100)
+    exchange: str | None = Field(default=None, pattern="^(okx|binance|bn)$")
 
 
 def _as_bool(raw: str | None, default: bool) -> bool:
@@ -57,6 +64,7 @@ def _as_bool(raw: str | None, default: bool) -> bool:
 def _read_settings() -> dict:
     db = get_db()
     s = get_settings()
+    rt = load_runtime_settings()
     mode = str(db.get_setting("exit_mode", s.exit_mode) or s.exit_mode)
     if mode not in ("fixed_usdt", "premium_multiple"):
         mode = "fixed_usdt"
@@ -102,6 +110,10 @@ def _read_settings() -> dict:
         "option_qty_eth": float(
             db.get_setting("option_qty_eth", str(s.option_qty_eth)) or s.option_qty_eth
         ),
+        "exchange": rt.exchange,
+        "perp_inst_id": rt.perp_inst_id,
+        "option_inst_family": rt.option_inst_family,
+        "index_inst_id": rt.index_inst_id,
         "ledger": Ledger(db).snapshot(),
     }
 
@@ -120,6 +132,21 @@ async def put_strategy_settings(
     s = get_settings()
     data = body.model_dump(exclude_none=True)
     equity_to_apply: float | None = None
+    switch_to: str | None = None
+
+    if "exchange" in data:
+        new_ex = normalize_exchange_name(str(data.pop("exchange")))
+        old_ex = normalize_exchange_name(
+            db.get_setting("exchange", s.exchange) or s.exchange
+        )
+        if new_ex != old_ex:
+            if Matcher(db).has_open_position():
+                raise HTTPException(
+                    status_code=409,
+                    detail="有未平仓，无法切换交易所；请先平仓后再改",
+                )
+            switch_to = new_ex
+
     if "initial_equity" in data:
         new_eq = float(data["initial_equity"])
         old_eq = float(
@@ -132,12 +159,25 @@ async def put_strategy_settings(
                     detail="有未平仓，无法重置模拟资金；请先平仓后再改",
                 )
             equity_to_apply = new_eq
+
     for k, v in data.items():
         if k in KEYS:
             db.set_setting(k, str(v))
+
     if equity_to_apply is not None:
         Ledger(db).reset_equity(
             equity_to_apply,
             note=f"设置模拟资金={equity_to_apply:.2f}",
         )
+
+    if switch_to is not None:
+        rt = persist_exchange_choice(switch_to)
+        try:
+            await reload_market_session(rt)
+        except Exception as e:
+            raise HTTPException(
+                status_code=502,
+                detail=f"交易所已切换为 {switch_to}，但行情重连失败: {e}",
+            ) from e
+
     return _read_settings()