devperf/backend/src/services/roi/strategy-params.ts

import { eq } from 'drizzle-orm';
import { db } from '../../db/index';
import { roiStrategies } from '../../db/schema';
import type { RoiCategory, StrategyParams } from './types';

const DEFAULTS: StrategyParams = {
  hourlyRate: 400,
  amortYears: 3,
  commitHourCoef: 0.5,
  taskHourCoef: 6,
};

let cache: Map<RoiCategory, StrategyParams> | null = null;
let cacheLoadedAt = 0;
const CACHE_TTL_MS = 60_000;  // 1 分钟缓存,改完策略最多 1 分钟生效

async function loadCache(): Promise<Map<RoiCategory, StrategyParams>> {
  const now = Date.now();
  if (cache && now - cacheLoadedAt < CACHE_TTL_MS) return cache;

  const rows = await db.select().from(roiStrategies);
  const map = new Map<RoiCategory, StrategyParams>();
  for (const row of rows) {
    const p = (row.params as Partial<StrategyParams>) || {};
    map.set(row.category, {
      hourlyRate: p.hourlyRate ?? DEFAULTS.hourlyRate,
      amortYears: p.amortYears ?? DEFAULTS.amortYears,
      commitHourCoef: p.commitHourCoef ?? DEFAULTS.commitHourCoef,
      taskHourCoef: p.taskHourCoef ?? DEFAULTS.taskHourCoef,
    });
  }
  cache = map;
  cacheLoadedAt = now;
  return map;
}

/**
 * 取某个分类的策略参数。未打标(null)时返回 cash_cow 的参数作为默认。
 */
export async function getStrategyParams(category: RoiCategory | null): Promise<StrategyParams> {
  const map = await loadCache();
  const cat: RoiCategory = category ?? 'cash_cow';
  return map.get(cat) ?? DEFAULTS;
}

export function invalidateStrategyCache(): void {
  cache = null;
  cacheLoadedAt = 0;
}