feat(stock): market_events (급변·거래량Z·외인순매도)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

stock/app/holdings_intel.py

@@ -124,6 +124,54 @@ def exit_rules(holding: dict, ticker_prices: "pd.DataFrame", params: dict) -> di
 ADD_SCORE = 70.0   # 이 이상이면 추가매수 후보
 
 
+# ---- Task 3.1: market_events ----
+
+_DEFAULT_EVENT_PARAMS = {"move_pct": 7.0, "vol_z": 2.5}
+
+
+def market_events(ticker: str, ticker_prices: "pd.DataFrame",
+                  ticker_flow: "pd.DataFrame | None", params: dict) -> list[dict]:
+    """일봉/flow 기반 시장 이벤트 (급변·거래량 Z·외인 순매도)."""
+    p = {**_DEFAULT_EVENT_PARAMS, **(params or {})}
+    events = []
+    if ticker_prices is None or ticker_prices.empty or len(ticker_prices) < 2:
+        return events
+    tp = ticker_prices.sort_values("date").reset_index(drop=True)
+    close = tp["close"].astype(float)
+    pct = (close.iloc[-1] - close.iloc[-2]) / close.iloc[-2] * 100.0 if close.iloc[-2] else 0.0
+    if abs(pct) >= p["move_pct"]:
+        events.append({
+            "type": "price_move",
+            "severity": "high" if abs(pct) >= p["move_pct"] * 1.5 else "med",
+            "summary": f"전일 대비 {pct:+.1f}%",
+        })
+    vol = tp["volume"].astype(float)
+    if len(vol) >= 21:
+        base = vol.iloc[-21:-1]
+        mu, sd = base.mean(), base.std(ddof=0)
+        last_vol = vol.iloc[-1]
+        if mu > 0 and (
+            (sd and (last_vol - mu) / sd >= p["vol_z"])
+            or (not sd and last_vol >= mu * p["vol_z"])  # sd=0 fallback: plain ratio
+        ):
+            z_txt = f"{(last_vol - mu) / sd:.1f}" if sd else f"ratio={last_vol / mu:.1f}x"
+            events.append({
+                "type": "volume_surge",
+                "severity": "med",
+                "summary": f"거래량 평소 대비 급증(Z={z_txt})",
+            })
+    if ticker_flow is not None and not ticker_flow.empty:
+        tf = ticker_flow.sort_values("date")
+        recent = tf["foreign_net"].astype(float).iloc[-3:]
+        if len(recent) >= 3 and (recent < 0).all():
+            events.append({
+                "type": "foreign_selling",
+                "severity": "med",
+                "summary": "외국인 3일 연속 순매도",
+            })
+    return events
+
+
 def decide_action(tech_score: float, exit_flags: dict, pnl: float | None,
                   add_score: float = ADD_SCORE) -> tuple[str, str]:
     """액션 결정 매트릭스: sell > trim > add > hold (우선순위 순).