// source/memory-store.ts
var calculateNextResetTime = (windowMs) => {
  const resetTime = new Date();
  resetTime.setMilliseconds(resetTime.getMilliseconds() + windowMs);
  return resetTime;
};
var MemoryStore = class {
  init(options) {
    this.windowMs = options.windowMs;
    this.resetTime = calculateNextResetTime(this.windowMs);
    this.hits = {};
    const interval = setInterval(async () => {
      await this.resetAll();
    }, this.windowMs);
    if (interval.unref) {
      interval.unref();
    }
  }
  async increment(key) {
    const totalHits = (this.hits[key] ?? 0) + 1;
    this.hits[key] = totalHits;
    return {
      totalHits,
      resetTime: this.resetTime
    };
  }
  async decrement(key) {
    const current = this.hits[key];
    if (current) {
      this.hits[key] = current - 1;
    }
  }
  async resetKey(key) {
    delete this.hits[key];
  }
  async resetAll() {
    this.hits = {};
    this.resetTime = calculateNextResetTime(this.windowMs);
  }
};

// source/lib.ts
var isLegacyStore = (store) => typeof store.incr === "function" && typeof store.increment !== "function";
var promisifyStore = (passedStore) => {
  if (!isLegacyStore(passedStore)) {
    return passedStore;
  }
  const legacyStore = passedStore;
  class PromisifiedStore {
    async increment(key) {
      return new Promise((resolve, reject) => {
        legacyStore.incr(key, (error, totalHits, resetTime) => {
          if (error)
            reject(error);
          resolve({ totalHits, resetTime });
        });
      });
    }
    async decrement(key) {
      return Promise.resolve(legacyStore.decrement(key));
    }
    async resetKey(key) {
      return Promise.resolve(legacyStore.resetKey(key));
    }
    async resetAll() {
      if (typeof legacyStore.resetAll === "function")
        return Promise.resolve(legacyStore.resetAll());
    }
  }
  return new PromisifiedStore();
};
var parseOptions = (passedOptions) => {
  const options = {
    windowMs: 60 * 1e3,
    store: new MemoryStore(),
    max: 5,
    message: "Too many requests, please try again later.",
    statusCode: 429,
    legacyHeaders: passedOptions.headers ?? true,
    standardHeaders: passedOptions.draft_polli_ratelimit_headers ?? false,
    requestPropertyName: "rateLimit",
    skipFailedRequests: false,
    skipSuccessfulRequests: false,
    requestWasSuccessful: (_request, response) => response.statusCode < 400,
    skip: (_request, _response) => false,
    keyGenerator: (request, _response) => {
      if (!request.ip) {
        console.error("WARN | `express-rate-limit` | `request.ip` is undefined. You can avoid this by providing a custom `keyGenerator` function, but it may be indicative of a larger issue.");
      }
      return request.ip;
    },
    handler: (_request, response, _next, _optionsUsed) => {
      response.status(options.statusCode).send(options.message);
    },
    onLimitReached: (_request, _response, _optionsUsed) => {
    },
    ...passedOptions
  };
  if (typeof options.store.incr !== "function" && typeof options.store.increment !== "function" || typeof options.store.decrement !== "function" || typeof options.store.resetKey !== "function" || typeof options.store.resetAll !== "undefined" && typeof options.store.resetAll !== "function" || typeof options.store.init !== "undefined" && typeof options.store.init !== "function") {
    throw new TypeError("An invalid store was passed. Please ensure that the store is a class that implements the `Store` interface.");
  }
  options.store = promisifyStore(options.store);
  return options;
};
var handleAsyncErrors = (fn) => async (request, response, next) => {
  try {
    await Promise.resolve(fn(request, response, next)).catch(next);
  } catch (error) {
    next(error);
  }
};
var rateLimit = (passedOptions) => {
  const options = parseOptions(passedOptions ?? {});
  if (typeof options.store.init === "function")
    options.store.init(options);
  const middleware = handleAsyncErrors(async (request, response, next) => {
    const skip = await options.skip(request, response);
    if (skip) {
      next();
      return;
    }
    const augmentedRequest = request;
    const key = await options.keyGenerator(request, response);
    const { totalHits, resetTime } = await options.store.increment(key);
    const retrieveQuota = typeof options.max === "function" ? options.max(request, response) : options.max;
    const maxHits = await retrieveQuota;
    augmentedRequest[options.requestPropertyName] = {
      limit: maxHits,
      current: totalHits,
      remaining: Math.max(maxHits - totalHits, 0),
      resetTime
    };
    if (options.legacyHeaders && !response.headersSent) {
      response.setHeader("X-RateLimit-Limit", maxHits);
      response.setHeader("X-RateLimit-Remaining", augmentedRequest[options.requestPropertyName].remaining);
      if (resetTime instanceof Date) {
        response.setHeader("Date", new Date().toUTCString());
        response.setHeader("X-RateLimit-Reset", Math.ceil(resetTime.getTime() / 1e3));
      }
    }
    if (options.standardHeaders && !response.headersSent) {
      response.setHeader("RateLimit-Limit", maxHits);
      response.setHeader("RateLimit-Remaining", augmentedRequest[options.requestPropertyName].remaining);
      if (resetTime) {
        const deltaSeconds = Math.ceil((resetTime.getTime() - Date.now()) / 1e3);
        response.setHeader("RateLimit-Reset", Math.max(0, deltaSeconds));
      }
    }
    if (options.skipFailedRequests || options.skipSuccessfulRequests) {
      let decremented = false;
      const decrementKey = async () => {
        if (!decremented) {
          await options.store.decrement(key);
          decremented = true;
        }
      };
      if (options.skipFailedRequests) {
        response.on("finish", async () => {
          if (!options.requestWasSuccessful(request, response))
            await decrementKey();
        });
        response.on("close", async () => {
          if (!response.writableEnded)
            await decrementKey();
        });
        response.on("error", async () => {
          await decrementKey();
        });
      }
      if (options.skipSuccessfulRequests) {
        response.on("finish", async () => {
          if (options.requestWasSuccessful(request, response))
            await decrementKey();
        });
      }
    }
    if (maxHits && totalHits === maxHits + 1) {
      options.onLimitReached(request, response, options);
    }
    if (maxHits && totalHits > maxHits) {
      if ((options.legacyHeaders || options.standardHeaders) && !response.headersSent) {
        response.setHeader("Retry-After", Math.ceil(options.windowMs / 1e3));
      }
      options.handler(request, response, next, options);
      return;
    }
    next();
  });
  middleware.resetKey = options.store.resetKey.bind(options.store);
  return middleware;
};
var lib_default = rateLimit;
export {
  lib_default as default,
  lib_default as rateLimit
};