/*
 * nghttp2 - HTTP/2 C Library
 *
 * Copyright (c) 2012 Tatsuhiro Tsujikawa
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#include "nghttp2_config.h"

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif // HAVE_UNISTD_H
#include <signal.h>
#include <getopt.h>

#include <cstdlib>
#include <cstring>
#include <cassert>
#include <string>
#include <iostream>
#include <string>

#include <openssl/ssl.h>
#include <openssl/err.h>
#include <openssl/conf.h>
#include <nghttp2/nghttp2.h>

#include "app_helper.h"
#include "HttpServer.h"
#include "util.h"
#include "ssl.h"

namespace nghttp2 {

namespace {
int parse_push_config(Config &config, const char *optarg) {
  const char *eq = strchr(optarg, '=');
  if (eq == NULL) {
    return -1;
  }
  auto &paths = config.push[std::string(optarg, eq)];
  auto optarg_end = optarg + strlen(optarg);
  auto i = eq + 1;
  for (;;) {
    const char *j = strchr(i, ',');
    if (j == NULL) {
      j = optarg_end;
    }
    paths.emplace_back(i, j);
    if (j == optarg_end) {
      break;
    }
    i = j;
    ++i;
  }

  return 0;
}
} // namespace

namespace {
void print_version(std::ostream &out) {
  out << "nghttpd nghttp2/" NGHTTP2_VERSION << std::endl;
}
} // namespace

namespace {
void print_usage(std::ostream &out) {
  out << "Usage: nghttpd [OPTION]... <PORT> [<PRIVATE_KEY> <CERT>]\n"
      << "HTTP/2 experimental server" << std::endl;
}
} // namespace

namespace {
void print_help(std::ostream &out) {
  Config config;
  print_usage(out);
  out << R"(
  <PORT>      Specify listening port number.
  <PRIVATE_KEY>
              Set  path  to  server's private  key.   Required  unless
              --no-tls is specified.
  <CERT>      Set  path  to  server's  certificate.   Required  unless
              --no-tls is specified.
Options:
  -a, --address=<ADDR>
              The address to bind to.  If not specified the default IP
              address determined by getaddrinfo is used.
  -D, --daemon
              Run in a background.  If -D is used, the current working
              directory is  changed to '/'.  Therefore  if this option
              is used, -d option must be specified.
  -V, --verify-client
              The server  sends a client certificate  request.  If the
              client did  not return  a certificate, the  handshake is
              terminated.   Currently,  this  option just  requests  a
              client certificate and does not verify it.
  -d, --htdocs=<PATH>
              Specify document root.  If this option is not specified,
              the document root is the current working directory.
  -v, --verbose
              Print debug information  such as reception/ transmission
              of frames and name/value pairs.
  --no-tls    Disable SSL/TLS.
  -c, --header-table-size=<SIZE>
              Specify decoder header table size.
  --color     Force colored log output.
  -p, --push=<PATH>=<PUSH_PATH,...>
              Push  resources <PUSH_PATH>s  when <PATH>  is requested.
              This option  can be used repeatedly  to specify multiple
              push  configurations.    <PATH>  and   <PUSH_PATH>s  are
              relative  to   document  root.   See   --htdocs  option.
              Example: -p/=/foo.png -p/doc=/bar.css
  -b, --padding=<N>
              Add at  most <N>  bytes to a  frame payload  as padding.
              Specify 0 to disable padding.
  -m, --max-concurrent-streams=<N>
              Set the maximum number of  the concurrent streams in one
              HTTP/2 session.
              Default: )" << config.max_concurrent_streams << R"(
  -n, --workers=<N>
              Set the number of worker threads.
              Default: 1
  -e, --error-gzip
              Make error response gzipped.
  --dh-param-file=<PATH>
              Path to file that contains  DH parameters in PEM format.
              Without  this   option,  DHE   cipher  suites   are  not
              available.
  --early-response
              Start sending response when request HEADERS is received,
              rather than complete request is received.
  --trailer=<HEADER>
              Add a trailer  header to a response.   <HEADER> must not
              include pseudo header field  (header field name starting
              with ':').  The  trailer is sent only if  a response has
              body part.  Example: --trailer 'foo: bar'.
  --hexdump   Display the  incoming traffic in  hexadecimal (Canonical
              hex+ASCII display).  If SSL/TLS  is used, decrypted data
              are used.
  --echo-upload
              Send back uploaded content if method is POST or PUT.
  --version   Display version information and exit.
  -h, --help  Display this help and exit.

--

  The <SIZE> argument is an integer and an optional unit (e.g., 10K is
  10 * 1024).  Units are K, M and G (powers of 1024).)" << std::endl;
}
} // namespace

int main(int argc, char **argv) {
#ifndef NOTHREADS
  ssl::LibsslGlobalLock lock;
#endif // NOTHREADS
  SSL_load_error_strings();
  SSL_library_init();
  OpenSSL_add_all_algorithms();
  OPENSSL_config(nullptr);

  Config config;
  bool color = false;
  while (1) {
    static int flag = 0;
    static option long_options[] = {
        {"address", required_argument, nullptr, 'a'},
        {"daemon", no_argument, nullptr, 'D'},
        {"htdocs", required_argument, nullptr, 'd'},
        {"help", no_argument, nullptr, 'h'},
        {"verbose", no_argument, nullptr, 'v'},
        {"verify-client", no_argument, nullptr, 'V'},
        {"header-table-size", required_argument, nullptr, 'c'},
        {"push", required_argument, nullptr, 'p'},
        {"padding", required_argument, nullptr, 'b'},
        {"max-concurrent-streams", required_argument, nullptr, 'm'},
        {"workers", required_argument, nullptr, 'n'},
        {"error-gzip", no_argument, nullptr, 'e'},
        {"no-tls", no_argument, &flag, 1},
        {"color", no_argument, &flag, 2},
        {"version", no_argument, &flag, 3},
        {"dh-param-file", required_argument, &flag, 4},
        {"early-response", no_argument, &flag, 5},
        {"trailer", required_argument, &flag, 6},
        {"hexdump", no_argument, &flag, 7},
        {"echo-upload", no_argument, &flag, 8},
        {nullptr, 0, nullptr, 0}};
    int option_index = 0;
    int c = getopt_long(argc, argv, "DVb:c:d:ehm:n:p:va:", long_options,
                        &option_index);
    char *end;
    if (c == -1) {
      break;
    }
    switch (c) {
    case 'a':
      config.address = optarg;
      break;
    case 'D':
      config.daemon = true;
      break;
    case 'V':
      config.verify_client = true;
      break;
    case 'b':
      config.padding = strtol(optarg, nullptr, 10);
      break;
    case 'd':
      config.htdocs = optarg;
      break;
    case 'e':
      config.error_gzip = true;
      break;
    case 'm': {
      // max-concurrent-streams option
      auto n = util::parse_uint(optarg);
      if (n == -1) {
        std::cerr << "-m: invalid argument: " << optarg << std::endl;
        exit(EXIT_FAILURE);
      }
      config.max_concurrent_streams = n;
      break;
    }
    case 'n':
#ifdef NOTHREADS
      std::cerr << "-n: WARNING: Threading disabled at build time, "
                << "no threads created." << std::endl;
#else
      errno = 0;
      config.num_worker = strtoul(optarg, &end, 10);
      if (errno == ERANGE || *end != '\0' || config.num_worker == 0) {
        std::cerr << "-n: Bad option value: " << optarg << std::endl;
        exit(EXIT_FAILURE);
      }
#endif // NOTHREADS
      break;
    case 'h':
      print_help(std::cout);
      exit(EXIT_SUCCESS);
    case 'v':
      config.verbose = true;
      break;
    case 'c':
      errno = 0;
      config.header_table_size = util::parse_uint_with_unit(optarg);
      if (config.header_table_size == -1) {
        std::cerr << "-c: Bad option value: " << optarg << std::endl;
        exit(EXIT_FAILURE);
      }
      break;
    case 'p':
      if (parse_push_config(config, optarg) != 0) {
        std::cerr << "-p: Bad option value: " << optarg << std::endl;
      }
      break;
    case '?':
      util::show_candidates(argv[optind - 1], long_options);
      exit(EXIT_FAILURE);
    case 0:
      switch (flag) {
      case 1:
        // no-tls option
        config.no_tls = true;
        break;
      case 2:
        // color option
        color = true;
        break;
      case 3:
        // version
        print_version(std::cout);
        exit(EXIT_SUCCESS);
      case 4:
        // dh-param-file
        config.dh_param_file = optarg;
        break;
      case 5:
        // early-response
        config.early_response = true;
        break;
      case 6: {
        // trailer option
        auto header = optarg;
        auto value = strchr(optarg, ':');
        if (!value) {
          std::cerr << "--trailer: invalid header: " << optarg << std::endl;
          exit(EXIT_FAILURE);
        }
        *value = 0;
        value++;
        while (isspace(*value)) {
          value++;
        }
        if (*value == 0) {
          // This could also be a valid case for suppressing a header
          // similar to curl
          std::cerr << "--trailer: invalid header - value missing: " << optarg
                    << std::endl;
          exit(EXIT_FAILURE);
        }
        config.trailer.emplace_back(header, value, false);
        util::inp_strlower(config.trailer.back().name);
        break;
      }
      case 7:
        // hexdump option
        config.hexdump = true;
        break;
      case 8:
        // echo-upload option
        config.echo_upload = true;
        break;
      }
      break;
    default:
      break;
    }
  }
  if (argc - optind < (config.no_tls ? 1 : 3)) {
    print_usage(std::cerr);
    std::cerr << "Too few arguments" << std::endl;
    exit(EXIT_FAILURE);
  }

  config.port = strtol(argv[optind++], nullptr, 10);

  if (!config.no_tls) {
    config.private_key_file = argv[optind++];
    config.cert_file = argv[optind++];
  }

  if (config.daemon) {
    if (config.htdocs.empty()) {
      print_usage(std::cerr);
      std::cerr << "-d option must be specified when -D is used." << std::endl;
      exit(EXIT_FAILURE);
    }
    if (daemon(0, 0) == -1) {
      perror("daemon");
      exit(EXIT_FAILURE);
    }
  }
  if (config.htdocs.empty()) {
    config.htdocs = "./";
  }

  set_color_output(color || isatty(fileno(stdout)));

  struct sigaction act;
  memset(&act, 0, sizeof(struct sigaction));
  act.sa_handler = SIG_IGN;
  sigaction(SIGPIPE, &act, nullptr);

  reset_timer();

  HttpServer server(&config);
  if (server.run() != 0) {
    exit(EXIT_FAILURE);
  }
  return 0;
}

} // namespace nghttp2

int main(int argc, char **argv) { return nghttp2::main(argc, argv); }