import { type Request, type Response, type NextFunction } from "express";

const TIER_FEATURES: Record<string, string[]> = {
  free: ["browse", "rate", "search"],
  premium: ["browse", "rate", "search", "similar-tools", "costs", "redundancy", "analytics-advanced", "trash", "compare", "watchlist", "tool-import"],
  enterprise: ["browse", "rate", "search", "similar-tools", "costs", "redundancy", "analytics-advanced", "trash", "compare", "watchlist", "tool-import", "sso", "audit-export", "api-access"],
};

export function getEntitlements(tier: string | undefined, role: string | undefined): string[] {
  if (role === "admin") {
    const all = new Set<string>();
    for (const features of Object.values(TIER_FEATURES)) {
      for (const f of features) all.add(f);
    }
    return [...all];
  }
  return TIER_FEATURES[tier ?? "free"] ?? TIER_FEATURES.free;
}

export function hasFeature(tier: string | undefined, feature: string, role?: string): boolean {
  return getEntitlements(tier, role).includes(feature);
}

export function requireFeature(feature: string) {
  return (req: Request, res: Response, next: NextFunction): void => {
    if (!req.session.user) {
      res.status(401).json({ error: "Authentication required" });
      return;
    }
    if (!hasFeature(req.session.user.tier, feature, req.session.user.role)) {
      res.status(403).json({ error: `Feature "${feature}" requires a higher tier` });
      return;
    }
    next();
  };
}