//
// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2019
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#include "td/telegram/Client.h"
#include "td/telegram/td_api.h"

#include "td/utils/common.h"
#include "td/utils/logging.h"
#include "td/utils/misc.h"

#include <cstdlib>
#include <iostream>
#include <utility>

static void usage() {
  td::TsCerr() << "Tests specified MTProto-proxies, outputs working proxies to stdout; exits with code 0 if a working proxy was found.\n";
  td::TsCerr() << "Usage: check_proxy [options] server:port:secret [server2:port2:secret2 ...]\n";
  td::TsCerr() << "Options:\n";
  td::TsCerr() << "  -v<N>\tSet verbosity level to N\n";
  td::TsCerr() << "  -h/--help\tDisplay this information\n";
  td::TsCerr() << "  -d/--dc-id\tIdentifier of a datacenter, to which try to connect (default is 2)\n";
  td::TsCerr() << "  -t/--timeout\tMaximum overall timeout for the request (default is 10 seconds)\n";
  std::exit(2);
}

int main(int argc, char **argv) {
  int new_verbosity_level = VERBOSITY_NAME(FATAL);

  td::vector<std::pair<td::string, td::td_api::object_ptr<td::td_api::testProxy>>> requests;

  auto add_proxy = [&requests](const td::string &arg) {
    auto secret_pos = arg.rfind(':');
    if (secret_pos == td::string::npos) {
      td::TsCerr() << "Error: failed to find proxy port and secret in \"" << arg << "\"\n";
      usage();
    }
    auto secret = arg.substr(secret_pos + 1);
    auto port_pos = arg.substr(0, secret_pos).rfind(':');
    if (port_pos == td::string::npos) {
      td::TsCerr() << "Error: failed to find proxy secret in \"" << arg << "\"\n";
      usage();
    }
    auto r_port = td::to_integer_safe<td::int32>(arg.substr(port_pos + 1, secret_pos - port_pos - 1));
    if (r_port.is_error()) {
      td::TsCerr() << "Error: failed to parse proxy port in \"" << arg << "\"\n";
      usage();
    }
    auto port = r_port.move_as_ok();
    auto server = arg.substr(0, port_pos);

    if (server.empty() || port <= 0 || port > 65536 || secret.empty()) {
      td::TsCerr() << "Error: proxy address to check is in wrong format: \"" << arg << "\"\n";
      usage();
    }

    requests.emplace_back(arg,
                          td::td_api::make_object<td::td_api::testProxy>(
                              server, port, td::td_api::make_object<td::td_api::proxyTypeMtproto>(secret), -1, -1));
  };

  td::int32 dc_id = 2;
  double timeout = 10.0;

  for (int i = 1; i < argc; i++) {
    td::string arg(argv[i]);
    if (arg.substr(0, 2) == "-v") {
      if (arg.size() == 2 && i + 1 < argc && argv[i + 1][0] != '-') {
        arg = argv[++i];
      } else {
        arg = arg.substr(2);
      }
      int new_verbosity = 1;
      while (arg[0] == 'v') {
        new_verbosity++;
        arg = arg.substr(1);
      }
      if (!arg.empty()) {
        new_verbosity += td::to_integer<int>(arg) - (new_verbosity == 1);
      }
      new_verbosity_level = VERBOSITY_NAME(FATAL) + new_verbosity;
    } else if (arg == "-t" || arg == "--timeout") {
      if (i + 1 == argc) {
        td::TsCerr() << "Value is required after " << arg;
        usage();
      }
      timeout = td::to_double(td::string(argv[++i]));
    } else if (arg == "-d" || arg == "--dc_id") {
      if (i + 1 == argc) {
        td::TsCerr() << "Value is required after " << arg;
        usage();
      }
      dc_id = td::to_integer<td::int32>(td::string(argv[++i]));
    } else if (arg[0] == '-') {
      usage();
    } else {
      add_proxy(arg);
    }
  }

  if (requests.empty()) {
    td::TsCerr() << "Error: proxy address to check is not specified\n";
    usage();
  }

  SET_VERBOSITY_LEVEL(new_verbosity_level);

  td::Client client;
  for (size_t i = 0; i < requests.size(); i++) {
    auto &request = requests[i].second;
    request->dc_id_ = dc_id;
    request->timeout_ = timeout;
    client.send({i + 1, std::move(request)});
  }
  size_t successful_requests = 0;
  size_t failed_requests = 0;

  while (successful_requests + failed_requests != requests.size()) {
    auto response = client.receive(100.0);
    if (1 <= response.id && response.id <= requests.size()) {
      auto &proxy = requests[static_cast<size_t>(response.id - 1)].first;
      if (response.object->get_id() == td::td_api::error::ID) {
        LOG(ERROR) << proxy << ": " << to_string(response.object);
        failed_requests++;
      } else {
        std::cout << proxy << std::endl;
        successful_requests++;
      }
    }
  }

  if (successful_requests == 0) {
    return 1;
  }
}