feat: AI事前预警 — 现金流预测+预警扩展+准确率+情景建议

backend/app/api/predict.py

@@ -1,10 +1,16 @@
 """预测模拟API — 管理会计OS"""
 import logging
-from fastapi import APIRouter, HTTPException
+from fastapi import APIRouter, HTTPException, Depends
 from app.utils.predict_engine import (
     cvp_analysis, npv, irr,
     sensitivity_analysis, scenario_analysis,
 )
+from app.utils.cash_forecast_engine import (
+    forecast_cash_flow, save_forecast_to_db,
+    calculate_accuracy, generate_scenario_suggestion,
+)
+from app.database import get_db
+from sqlalchemy.orm import Session
 
 logger = logging.getLogger("cma.predict")
 router = APIRouter(prefix="/api/cma/predict", tags=["预测模拟"])
@@ -154,6 +160,105 @@ def api_cvp_detailed(data: dict):
         raise HTTPException(400, f"CVP详细分析失败: {str(e)}")
 
 
+# ── 现金流预测（AI事前预警） ────────────────────────────────────
+
+
+@router.post("/cash-forecast")
+def api_cash_forecast(data: dict, db: Session = Depends(get_db)):
+    """现金流预测 — 根据历史KPI推算未来30天现金流"""
+    try:
+        entity_id = int(data.get("entity_id", 1))
+        days = int(data.get("days", 30))
+        current_cash = float(data["current_cash"]) if data.get("current_cash") else None
+        result = forecast_cash_flow(entity_id, db, days, current_cash)
+        # 保存到数据库
+        try:
+            save_forecast_to_db(entity_id, result, db)
+        except Exception as e:
+            logger.warning(f"保存预测结果失败: {e}")
+        return result
+    except Exception as e:
+        raise HTTPException(400, f"现金流预测失败: {str(e)}")
+
+
+@router.get("/cash-forecast/history")
+def api_cash_forecast_history(
+    entity_id: int = 1,
+    days: int = 30,
+    db: Session = Depends(get_db),
+):
+    """获取已保存的现金流预测历史"""
+    from app.models import CashForecast
+    forecasts = db.query(CashForecast).filter(
+        CashForecast.entity_id == entity_id,
+    ).order_by(CashForecast.forecast_date.desc()).limit(days).all()
+    return {
+        "data": [{
+            "id": f.id,
+            "forecast_date": f.forecast_date.isoformat(),
+            "predicted_cash": f.predicted_cash,
+            "lower_bound": f.lower_bound,
+            "upper_bound": f.upper_bound,
+            "alert_status": f.alert_status,
+        } for f in forecasts]
+    }
+
+
+@router.get("/accuracy")
+def api_forecast_accuracy(
+    entity_id: int = 1,
+    db: Session = Depends(get_db),
+):
+    """预测准确率报表 — 上期预测 vs 本期实际"""
+    try:
+        results = calculate_accuracy(entity_id, db)
+
+        # 计算整体MAE/MAPE
+        if results:
+            total_mae = sum(r["mae"] for r in results) / len(results)
+            total_mape = sum(r["mape"] for r in results) / len(results)
+        else:
+            total_mae = 0
+            total_mape = 0
+
+        return {
+            "data": results,
+            "summary": {
+                "total_periods": len(results),
+                "avg_mae": round(total_mae, 2),
+                "avg_mape": round(total_mape, 2),
+            },
+        }
+    except Exception as e:
+        raise HTTPException(400, f"获取准确率失败: {str(e)}")
+
+
+@router.get("/scenario-suggestions")
+def api_scenario_suggestions(alert_type: str = None):
+    """获取情景建议模板"""
+    types = ["cash_low", "cash_critical", "cost_high", "revenue_drop"]
+    results = []
+    for at in types:
+        if alert_type and at != alert_type:
+            continue
+        sug = generate_scenario_suggestion(at, "")
+        results.append({"alert_type": at, **sug})
+    return {"data": results}
+
+
+@router.post("/scenario-suggestion/generate")
+def api_generate_suggestion(data: dict):
+    """根据预警信息动态生成情景建议"""
+    try:
+        alert_type = data.get("alert_type", "cash_low")
+        kpi_name = data.get("kpi_name", "未知KPI")
+        extra = data.get("extra", {})
+        sug = generate_scenario_suggestion(alert_type, kpi_name, extra)
+        return sug
+    except Exception as e:
+        raise HTTPException(400, f"生成建议失败: {str(e)}")
+
+
 # ── 实物期权计算器 ─────────────────────────────────────────────
 import math