import { SECTOR, ASSET_TYPE, REGIME } from '../config/constants.js';

export class MarketRegime {
  constructor(marketContext) {
    const b = marketContext?.benchmarks ?? {};
    this.marketPE = b.marketPE ?? 22;
    this.techPE = b.techPE ?? 30;
    this.reitYield = b.reitYield ?? 3.5;
    this.igSpread = b.igSpread ?? 1.0;
    this.rateRegime = marketContext?.rateRegime ?? REGIME.NORMAL;
    this.volatilityRegime = marketContext?.volatilityRegime ?? REGIME.NORMAL;
  }

  getInflatedOverrides(type, sector) {
    if (type === ASSET_TYPE.STOCK) return this._stock(sector);
    if (type === ASSET_TYPE.ETF) return this._etf();
    if (type === ASSET_TYPE.BOND) return this._bond();
    return { gates: {}, thresholds: {} };
  }

  _stock(sector) {
    if (sector === SECTOR.REIT) {
      return {
        gates: {},
        // In HIGH rate environment tighten REIT yield floor — REITs must compete harder with bonds.
        thresholds: {
          minYield: +(this.reitYield * (this.rateRegime === REGIME.HIGH ? 0.95 : 0.85)).toFixed(2),
          maxPFFO: 20,
        },
      };
    }
    if (sector === SECTOR.TECHNOLOGY) {
      return {
        gates: {
          maxPERatio: Math.round(this.techPE * 1.3),
          maxPegGate: +(this.techPE / 15).toFixed(1),
        },
        thresholds: {},
      };
    }
    // In HIGH rate environment, compress the P/E tolerance — higher rates mean
    // future earnings are discounted more aggressively (lower DCF valuations).
    const peMultiplier = this.rateRegime === REGIME.HIGH ? 1.2 : 1.5;
    return {
      gates: {
        maxPERatio: Math.round(this.marketPE * peMultiplier),
        maxPegGate: +(this.marketPE / 12).toFixed(1),
      },
      thresholds: {},
    };
  }

  _etf() {
    return { gates: { maxExpenseRatio: 0.75 }, thresholds: { minYield: 0.5 } };
  }

  _bond() {
    // In HIGH rate environment demand a wider spread — the opportunity cost of holding
    // corporate bonds over Treasuries is higher when risk-free rate is elevated.
    const spreadMultiplier = this.rateRegime === REGIME.HIGH ? 0.9 : 0.8;
    return { gates: {}, thresholds: { minSpread: +(this.igSpread * spreadMultiplier).toFixed(2) } };
  }
}