// Copyright 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 "base/command_line.h"
#include "content/browser/renderer_host/render_process_host_impl.h"
#include "content/common/child_process_messages.h"
#include "content/public/browser/render_process_host.h"
#include "content/public/browser/render_process_host_observer.h"
#include "content/public/browser/render_view_host.h"
#include "content/public/browser/web_contents.h"
#include "content/public/common/content_switches.h"
#include "content/public/common/url_constants.h"
#include "content/public/test/content_browser_test.h"
#include "content/public/test/content_browser_test_utils.h"
#include "content/shell/browser/shell.h"
#include "net/test/embedded_test_server/embedded_test_server.h"

#if defined(OS_WIN)
#include "base/win/windows_version.h"
#endif

namespace content {
namespace {

int RenderProcessHostCount() {
  content::RenderProcessHost::iterator hosts =
      content::RenderProcessHost::AllHostsIterator();
  int count = 0;
  while (!hosts.IsAtEnd()) {
    if (hosts.GetCurrentValue()->HasConnection())
      count++;
    hosts.Advance();
  }
  return count;
}

class RenderProcessHostTest : public ContentBrowserTest,
                              public RenderProcessHostObserver {
 public:
  RenderProcessHostTest() : process_exits_(0), host_destructions_(0) {}

 protected:
  // RenderProcessHostObserver:
  void RenderProcessExited(RenderProcessHost* host,
                           base::TerminationStatus status,
                           int exit_code) override {
    ++process_exits_;
  }
  void RenderProcessHostDestroyed(RenderProcessHost* host) override {
    ++host_destructions_;
  }

  int process_exits_;
  int host_destructions_;
};

// Sometimes the renderer process's ShutdownRequest (corresponding to the
// ViewMsg_WasSwappedOut from a previous navigation) doesn't arrive until after
// the browser process decides to re-use the renderer for a new purpose.  This
// test makes sure the browser doesn't let the renderer die in that case.  See
// http://crbug.com/87176.
IN_PROC_BROWSER_TEST_F(RenderProcessHostTest,
                       ShutdownRequestFromActiveTabIgnored) {
  ASSERT_TRUE(embedded_test_server()->InitializeAndWaitUntilReady());

  GURL test_url = embedded_test_server()->GetURL("/simple_page.html");
  NavigateToURL(shell(), test_url);
  RenderProcessHost* rph =
      shell()->web_contents()->GetRenderViewHost()->GetProcess();

  host_destructions_ = 0;
  process_exits_ = 0;
  rph->AddObserver(this);
  ChildProcessHostMsg_ShutdownRequest msg;
  rph->OnMessageReceived(msg);

  // If the RPH sends a mistaken ChildProcessMsg_Shutdown, the renderer process
  // will take some time to die. Wait for a second tab to load in order to give
  // that time to happen.
  NavigateToURL(CreateBrowser(), test_url);

  EXPECT_EQ(0, process_exits_);
  if (!host_destructions_)
    rph->RemoveObserver(this);
}

IN_PROC_BROWSER_TEST_F(RenderProcessHostTest,
                       GuestsAreNotSuitableHosts) {
  // Set max renderers to 1 to force running out of processes.
  content::RenderProcessHost::SetMaxRendererProcessCount(1);

  ASSERT_TRUE(embedded_test_server()->InitializeAndWaitUntilReady());

  GURL test_url = embedded_test_server()->GetURL("/simple_page.html");
  NavigateToURL(shell(), test_url);
  RenderProcessHost* rph =
      shell()->web_contents()->GetRenderViewHost()->GetProcess();
  // Make it believe it's a guest.
  reinterpret_cast<RenderProcessHostImpl*>(rph)->
      set_is_for_guests_only_for_testing(true);
  EXPECT_EQ(1, RenderProcessHostCount());

  // Navigate to a different page.
  GURL::Replacements replace_host;
  replace_host.SetHostStr("localhost");
  GURL another_url = embedded_test_server()->GetURL("/simple_page.html");
  another_url = another_url.ReplaceComponents(replace_host);
  NavigateToURL(CreateBrowser(), another_url);

  // Expect that we got another process (the guest renderer was not reused).
  EXPECT_EQ(2, RenderProcessHostCount());
}

class ShellCloser : public RenderProcessHostObserver {
 public:
  ShellCloser(Shell* shell, std::string* logging_string)
      : shell_(shell), logging_string_(logging_string) {}

 protected:
  // RenderProcessHostObserver:
  void RenderProcessExited(RenderProcessHost* host,
                           base::TerminationStatus status,
                           int exit_code) override {
    logging_string_->append("ShellCloser::RenderProcessExited ");
    shell_->Close();
  }

  void RenderProcessHostDestroyed(RenderProcessHost* host) override {
    logging_string_->append("ShellCloser::RenderProcessHostDestroyed ");
  }

  Shell* shell_;
  std::string* logging_string_;
};

class ObserverLogger : public RenderProcessHostObserver {
 public:
  explicit ObserverLogger(std::string* logging_string)
      : logging_string_(logging_string), host_destroyed_(false) {}

  bool host_destroyed() { return host_destroyed_; }

 protected:
  // RenderProcessHostObserver:
  void RenderProcessExited(RenderProcessHost* host,
                           base::TerminationStatus status,
                           int exit_code) override {
    logging_string_->append("ObserverLogger::RenderProcessExited ");
  }

  void RenderProcessHostDestroyed(RenderProcessHost* host) override {
    logging_string_->append("ObserverLogger::RenderProcessHostDestroyed ");
    host_destroyed_ = true;
  }

  std::string* logging_string_;
  bool host_destroyed_;
};

IN_PROC_BROWSER_TEST_F(RenderProcessHostTest,
                       AllProcessExitedCallsBeforeAnyHostDestroyedCalls) {
  ASSERT_TRUE(embedded_test_server()->InitializeAndWaitUntilReady());

  GURL test_url = embedded_test_server()->GetURL("/simple_page.html");
  NavigateToURL(shell(), test_url);

  std::string logging_string;
  ShellCloser shell_closer(shell(), &logging_string);
  ObserverLogger observer_logger(&logging_string);
  RenderProcessHost* rph =
      shell()->web_contents()->GetRenderViewHost()->GetProcess();

  // Ensure that the ShellCloser observer is first, so that it will have first
  // dibs on the ProcessExited callback.
  rph->AddObserver(&shell_closer);
  rph->AddObserver(&observer_logger);

  // This will crash the render process, and start all the callbacks.
  // We can't use NavigateToURL here since it accesses the shell() after
  // navigating, which the shell_closer deletes.
  NavigateToURLBlockUntilNavigationsComplete(
      shell(), GURL(kChromeUICrashURL), 1);

  // The key here is that all the RenderProcessExited callbacks precede all the
  // RenderProcessHostDestroyed callbacks.
  EXPECT_EQ("ShellCloser::RenderProcessExited "
            "ObserverLogger::RenderProcessExited "
            "ShellCloser::RenderProcessHostDestroyed "
            "ObserverLogger::RenderProcessHostDestroyed ", logging_string);

  // If the test fails, and somehow the RPH is still alive somehow, at least
  // deregister the observers so that the test fails and doesn't also crash.
  if (!observer_logger.host_destroyed()) {
    rph->RemoveObserver(&shell_closer);
    rph->RemoveObserver(&observer_logger);
  }
}

}  // namespace
}  // namespace content