import { SECTOR, ASSET_TYPE, REGIME } from '../config/constants.js';
import type { MarketContext, AssetType } from '../types.js';

interface InflatedOverrides {
  gates: Record<string, number>;
  thresholds: Record<string, number>;
}

export class MarketRegime {
  private marketPE: number;
  private techPE: number;
  private reitYield: number;
  private igSpread: number;
  private rateRegime: string;
  private volatilityRegime: string;

  constructor(marketContext: Partial<MarketContext>) {
    const b = marketContext?.benchmarks ?? ({} as 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: AssetType, sector?: string): InflatedOverrides {
    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: {} };
  }

  private _stock(sector?: string): InflatedOverrides {
    if (sector === SECTOR.REIT) {
      return {
        gates: {},
        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: {},
      };
    }
    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: {},
    };
  }

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

  private _bond(): InflatedOverrides {
    const spreadMultiplier = this.rateRegime === REGIME.HIGH ? 0.9 : 0.8;
    return {
      gates: {},
      thresholds: { minSpread: +(this.igSpread * spreadMultiplier).toFixed(2) },
    };
  }
}