// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <stdio.h>
#include <string>
#include <vector>

#include "base/at_exit.h"
#include "base/bind.h"
#include "base/callback.h"
#include "base/command_line.h"
#include "base/files/file_path.h"
#include "base/lazy_instance.h"
#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "base/message_loop/message_loop.h"
#include "base/run_loop.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/synchronization/waitable_event.h"
#include "base/threading/thread.h"
#include "base/threading/thread_local.h"
#include "chrome/test/chromedriver/chrome/version.h"
#include "chrome/test/chromedriver/logging.h"
#include "chrome/test/chromedriver/server/http_handler.h"
#include "net/base/ip_endpoint.h"
#include "net/base/net_errors.h"
#include "net/server/http_server.h"
#include "net/server/http_server_request_info.h"
#include "net/server/http_server_response_info.h"
#include "net/socket/tcp_listen_socket.h"

namespace {

typedef base::Callback<
    void(const net::HttpServerRequestInfo&, const HttpResponseSenderFunc&)>
    HttpRequestHandlerFunc;

class HttpServer : public net::HttpServer::Delegate {
 public:
  explicit HttpServer(const HttpRequestHandlerFunc& handle_request_func)
      : handle_request_func_(handle_request_func),
        weak_factory_(this) {}

  virtual ~HttpServer() {}

  bool Start(int port) {
    server_ = new net::HttpServer(
        net::TCPListenSocketFactory("0.0.0.0", port), this);
    net::IPEndPoint address;
    return server_->GetLocalAddress(&address) == net::OK;
  }

  // Overridden from net::HttpServer::Delegate:
  virtual void OnHttpRequest(int connection_id,
                             const net::HttpServerRequestInfo& info) OVERRIDE {
    handle_request_func_.Run(
        info,
        base::Bind(&HttpServer::OnResponse,
                   weak_factory_.GetWeakPtr(),
                   connection_id));
  }
  virtual void OnWebSocketRequest(
      int connection_id,
      const net::HttpServerRequestInfo& info) OVERRIDE {}
  virtual void OnWebSocketMessage(int connection_id,
                                  const std::string& data) OVERRIDE {}
  virtual void OnClose(int connection_id) OVERRIDE {}

 private:
  void OnResponse(int connection_id,
                  scoped_ptr<net::HttpServerResponseInfo> response) {
    // Don't support keep-alive, since there's no way to detect if the
    // client is HTTP/1.0. In such cases, the client may hang waiting for
    // the connection to close (e.g., python 2.7 urllib).
    response->AddHeader("Connection", "close");
    server_->SendResponse(connection_id, *response);
    server_->Close(connection_id);
  }

  HttpRequestHandlerFunc handle_request_func_;
  scoped_refptr<net::HttpServer> server_;
  base::WeakPtrFactory<HttpServer> weak_factory_;  // Should be last.
};

void SendResponseOnCmdThread(
    const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
    const HttpResponseSenderFunc& send_response_on_io_func,
    scoped_ptr<net::HttpServerResponseInfo> response) {
  io_task_runner->PostTask(
      FROM_HERE, base::Bind(send_response_on_io_func, base::Passed(&response)));
}

void HandleRequestOnCmdThread(
    HttpHandler* handler,
    const net::HttpServerRequestInfo& request,
    const HttpResponseSenderFunc& send_response_func) {
  handler->Handle(request, send_response_func);
}

void HandleRequestOnIOThread(
    const scoped_refptr<base::SingleThreadTaskRunner>& cmd_task_runner,
    const HttpRequestHandlerFunc& handle_request_on_cmd_func,
    const net::HttpServerRequestInfo& request,
    const HttpResponseSenderFunc& send_response_func) {
  cmd_task_runner->PostTask(
      FROM_HERE,
      base::Bind(handle_request_on_cmd_func,
                 request,
                 base::Bind(&SendResponseOnCmdThread,
                            base::MessageLoopProxy::current(),
                            send_response_func)));
}

base::LazyInstance<base::ThreadLocalPointer<HttpServer> >
    lazy_tls_server = LAZY_INSTANCE_INITIALIZER;

void StopServerOnIOThread() {
  // Note, |server| may be NULL.
  HttpServer* server = lazy_tls_server.Pointer()->Get();
  lazy_tls_server.Pointer()->Set(NULL);
  delete server;
}

void StartServerOnIOThread(int port,
                           const HttpRequestHandlerFunc& handle_request_func) {
  scoped_ptr<HttpServer> temp_server(new HttpServer(handle_request_func));
  if (!temp_server->Start(port)) {
    printf("Port not available. Exiting...\n");
    exit(1);
  }
  lazy_tls_server.Pointer()->Set(temp_server.release());
}

void RunServer(int port, const std::string& url_base, int adb_port) {
  base::Thread io_thread("ChromeDriver IO");
  CHECK(io_thread.StartWithOptions(
      base::Thread::Options(base::MessageLoop::TYPE_IO, 0)));

  base::MessageLoop cmd_loop;
  base::RunLoop cmd_run_loop;
  HttpHandler handler(cmd_run_loop.QuitClosure(),
                      io_thread.message_loop_proxy(),
                      url_base,
                      adb_port);
  HttpRequestHandlerFunc handle_request_func =
      base::Bind(&HandleRequestOnCmdThread, &handler);

  io_thread.message_loop()
      ->PostTask(FROM_HERE,
                 base::Bind(&StartServerOnIOThread,
                            port,
                            base::Bind(&HandleRequestOnIOThread,
                                       cmd_loop.message_loop_proxy(),
                                       handle_request_func)));
  // Run the command loop. This loop is quit after the response for a shutdown
  // request is posted to the IO loop. After the command loop quits, a task
  // is posted to the IO loop to stop the server. Lastly, the IO thread is
  // destroyed, which waits until all pending tasks have been completed.
  // This assumes the response is sent synchronously as part of the IO task.
  cmd_run_loop.Run();
  io_thread.message_loop()
      ->PostTask(FROM_HERE, base::Bind(&StopServerOnIOThread));
}

}  // namespace

int main(int argc, char *argv[]) {
  CommandLine::Init(argc, argv);

  base::AtExitManager at_exit;
  CommandLine* cmd_line = CommandLine::ForCurrentProcess();

  // Parse command line flags.
  int port = 9515;
  int adb_port = 5037;
  std::string url_base;
  if (cmd_line->HasSwitch("h") || cmd_line->HasSwitch("help")) {
    std::string options;
    const char* kOptionAndDescriptions[] = {
        "port=PORT", "port to listen on",
        "adb-port=PORT", "adb server port",
        "log-path=FILE", "write server log to file instead of stderr, "
            "increases log level to INFO",
        "verbose", "log verbosely",
        "silent", "log nothing",
        "url-base", "base URL path prefix for commands, e.g. wd/url",
    };
    for (size_t i = 0; i < arraysize(kOptionAndDescriptions) - 1; i += 2) {
      options += base::StringPrintf(
          "  --%-30s%s\n",
          kOptionAndDescriptions[i], kOptionAndDescriptions[i + 1]);
    }
    printf("Usage: %s [OPTIONS]\n\nOptions\n%s", argv[0], options.c_str());
    return 0;
  }
  if (cmd_line->HasSwitch("port")) {
    if (!base::StringToInt(cmd_line->GetSwitchValueASCII("port"), &port)) {
      printf("Invalid port. Exiting...\n");
      return 1;
    }
  }
  if (cmd_line->HasSwitch("adb-port")) {
    if (!base::StringToInt(cmd_line->GetSwitchValueASCII("adb-port"),
                           &adb_port)) {
      printf("Invalid adb-port. Exiting...\n");
      return 1;
    }
  }
  if (cmd_line->HasSwitch("url-base"))
    url_base = cmd_line->GetSwitchValueASCII("url-base");
  if (url_base.empty() || url_base[0] != '/')
    url_base = "/" + url_base;
  if (url_base[url_base.length() - 1] != '/')
    url_base = url_base + "/";
  if (!cmd_line->HasSwitch("silent")) {
    printf(
        "Starting ChromeDriver (v%s) on port %d\n", kChromeDriverVersion, port);
    fflush(stdout);
  }

  if (!InitLogging()) {
    printf("Unable to initialize logging. Exiting...\n");
    return 1;
  }

  RunServer(port, url_base, adb_port);
  return 0;
}