#include <cstdint>

#include <cstring>

#include <httplib.h>

class FuzzedStream : public httplib::Stream {

public:

  FuzzedStream(const uint8_t *data, size_t size)

      : data_(data), size_(size), read_pos_(0) {}

  ssize_t read(char *ptr, size_t size) override {

    if (size + read_pos_ > size_) { size = size_ - read_pos_; }

    memcpy(ptr, data_ + read_pos_, size);

    read_pos_ += size;

    return static_cast<ssize_t>(size);

  }

  ssize_t write(const char *ptr, size_t size) override {

    request_.append(ptr, size);

    return static_cast<ssize_t>(size);

  }

  ssize_t write(const char *ptr) { return write(ptr, strlen(ptr)); }

  ssize_t write(const std::string &s) { return write(s.data(), s.size()); }

  bool is_readable() const override { return true; }

  bool wait_readable() const override { return true; }

  bool wait_writable() const override { return true; }

  void get_remote_ip_and_port(std::string &ip, int &port) const override {

    ip = "127.0.0.1";

    port = 8080;

  }

  void get_local_ip_and_port(std::string &ip, int &port) const override {

    ip = "127.0.0.1";

    port = 8080;

  }

  socket_t socket() const override { return 0; }

  time_t duration() const override { return 0; };

private:

  const uint8_t *data_;

  size_t size_;

  size_t read_pos_;

  std::string request_;

};

class FuzzableClient : public httplib::ClientImpl {

public:

  FuzzableClient() : httplib::ClientImpl("localhost", 8080) {}

  void ProcessFuzzedResponse(FuzzedStream &stream, const std::string &method) {

    httplib::Request req;

    req.method = method;

    req.path = "/";

    httplib::Response res;

    bool close_connection = false;

    httplib::Error error = httplib::Error::Success;

    process_request(stream, req, res, close_connection, error);

  }

};

extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {

  if (size < 1) return 0;

  FuzzedStream stream{data + 1, size - 1};

  FuzzableClient client;

  // Use the first byte to select method

  std::string method;

  switch (data[0] % 6) {

  case 0: method = "GET"; break;

  case 1: method = "POST"; break;

  case 2: method = "PUT"; break;

  case 3: method = "PATCH"; break;

  case 4: method = "DELETE"; break;

  case 5: method = "OPTIONS"; break;

  }

  client.ProcessFuzzedResponse(stream, method);

  return 0;

}