// Copyright (c) 2015 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 <oleacc.h>

#include "base/macros.h"
#include "base/strings/string_util.h"
#include "base/win/scoped_bstr.h"
#include "base/win/scoped_com_initializer.h"
#include "base/win/scoped_comptr.h"
#include "base/win/scoped_variant.h"
#include "chrome/app/chrome_command_ids.h"
#include "chrome/browser/ui/browser.h"
#include "chrome/browser/ui/browser_commands.h"
#include "chrome/browser/ui/browser_window.h"
#include "chrome/browser/ui/views/frame/browser_view.h"
#include "chrome/browser/ui/views/omnibox/omnibox_view_views.h"
#include "chrome/browser/ui/views/toolbar/toolbar_view.h"
#include "chrome/test/base/in_process_browser_test.h"
#include "chrome/test/base/interactive_test_utils.h"
#include "chrome/test/base/ui_test_utils.h"
#include "components/omnibox/browser/omnibox_view.h"
#include "content/public/browser/browser_accessibility_state.h"
#include "net/dns/mock_host_resolver.h"
#include "net/test/embedded_test_server/embedded_test_server.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "ui/base/test/ui_controls.h"
#include "url/gurl.h"

// We could move this into a utility file in the future if it ends up
// being useful to other tests.
class WinAccessibilityEventMonitor {
 public:
  WinAccessibilityEventMonitor(UINT event_min, UINT event_max);
  ~WinAccessibilityEventMonitor();

  // Blocks until the next event is received. When it's received, it
  // queries accessibility information about the object that fired the
  // event and populates the event, hwnd, role, state, and name in the
  // passed arguments.
  void WaitForNextEvent(DWORD* out_event,
                        HWND* out_hwnd,
                        UINT* out_role,
                        UINT* out_state,
                        std::string* out_name);

 private:
  void OnWinEventHook(HWINEVENTHOOK handle,
                      DWORD event,
                      HWND hwnd,
                      LONG obj_id,
                      LONG child_id,
                      DWORD event_thread,
                      DWORD event_time);

  static void CALLBACK WinEventHookThunk(
      HWINEVENTHOOK handle,
      DWORD event,
      HWND hwnd,
      LONG obj_id,
      LONG child_id,
      DWORD event_thread,
      DWORD event_time);

  struct EventInfo {
    DWORD event;
    HWND hwnd;
    LONG obj_id;
    LONG child_id;
  };

  std::deque<EventInfo> event_queue_;
  scoped_refptr<content::MessageLoopRunner> loop_runner_;
  HWINEVENTHOOK win_event_hook_handle_;
  static WinAccessibilityEventMonitor* instance_;

  DISALLOW_COPY_AND_ASSIGN(WinAccessibilityEventMonitor);
};

// static
WinAccessibilityEventMonitor* WinAccessibilityEventMonitor::instance_ = NULL;

WinAccessibilityEventMonitor::WinAccessibilityEventMonitor(
    UINT event_min, UINT event_max) {
  CHECK(!instance_) << "There can be only one instance of"
                    << " WinAccessibilityEventMonitor at a time.";
  instance_ = this;
  win_event_hook_handle_ = SetWinEventHook(
      event_min,
      event_max,
      NULL,
      &WinAccessibilityEventMonitor::WinEventHookThunk,
      GetCurrentProcessId(),
      0,  // Hook all threads
      WINEVENT_OUTOFCONTEXT);
}

WinAccessibilityEventMonitor::~WinAccessibilityEventMonitor() {
  UnhookWinEvent(win_event_hook_handle_);
  instance_ = NULL;
}

void WinAccessibilityEventMonitor::WaitForNextEvent(
    DWORD* out_event,
    HWND* out_hwnd,
    UINT* out_role,
    UINT* out_state,
    std::string* out_name) {
  if (event_queue_.empty()) {
    loop_runner_ = new content::MessageLoopRunner();
    loop_runner_->Run();
    loop_runner_ = NULL;
  }
  EventInfo event_info = event_queue_.front();
  event_queue_.pop_front();

  *out_event = event_info.event;
  *out_hwnd = event_info.hwnd;

  base::win::ScopedComPtr<IAccessible> acc_obj;
  base::win::ScopedVariant child_variant;
  CHECK(S_OK == AccessibleObjectFromEvent(
      event_info.hwnd, event_info.obj_id, event_info.child_id,
      acc_obj.Receive(), child_variant.Receive()));

  base::win::ScopedVariant role_variant;
  if (S_OK == acc_obj->get_accRole(child_variant, role_variant.Receive()))
    *out_role = V_I4(role_variant.ptr());
  else
    *out_role = 0;

  base::win::ScopedVariant state_variant;
  if (S_OK == acc_obj->get_accState(child_variant, state_variant.Receive()))
    *out_state = V_I4(state_variant.ptr());
  else
    *out_state = 0;

  base::win::ScopedBstr name_bstr;
  HRESULT hr = acc_obj->get_accName(child_variant, name_bstr.Receive());
  if (S_OK == hr)
    *out_name = base::UTF16ToUTF8(base::string16(name_bstr));
  else
    *out_name = "";
}

void WinAccessibilityEventMonitor::OnWinEventHook(
    HWINEVENTHOOK handle,
    DWORD event,
    HWND hwnd,
    LONG obj_id,
    LONG child_id,
    DWORD event_thread,
    DWORD event_time) {
  EventInfo event_info;
  event_info.event = event;
  event_info.hwnd = hwnd;
  event_info.obj_id = obj_id;
  event_info.child_id = child_id;
  event_queue_.push_back(event_info);
  if (loop_runner_.get())
    loop_runner_->Quit();
}

// static
void CALLBACK WinAccessibilityEventMonitor::WinEventHookThunk(
    HWINEVENTHOOK handle,
    DWORD event,
    HWND hwnd,
    LONG obj_id,
    LONG child_id,
    DWORD event_thread,
    DWORD event_time) {
  if (instance_) {
    instance_->OnWinEventHook(handle, event, hwnd, obj_id, child_id,
                              event_thread, event_time);
  }
}

class NavigationAccessibilityTest : public InProcessBrowserTest {
 protected:
  NavigationAccessibilityTest() {}
  ~NavigationAccessibilityTest() override {}

  void SendKeyPress(ui::KeyboardCode key) {
    gfx::NativeWindow native_window = browser()->window()->GetNativeWindow();
    ASSERT_NO_FATAL_FAILURE(
        ASSERT_TRUE(
            ui_test_utils::SendKeyPressToWindowSync(
                native_window, key, false, false, false, false)));
  }

 private:
  base::win::ScopedCOMInitializer com_initializer_;

  DISALLOW_COPY_AND_ASSIGN(NavigationAccessibilityTest);
};

// Tests that when focus is in the omnibox and the user types a url and
// presses enter, no focus events are sent on the old document.
// TODO(dmazzoni): enable this test.  http://crbug.com/421116
IN_PROC_BROWSER_TEST_F(NavigationAccessibilityTest,
                       DISABLED_TestNavigateToNewUrl) {
  content::BrowserAccessibilityState::GetInstance()->EnableAccessibility();

  ui_test_utils::NavigateToURL(browser(),
                               GURL("data:text/html;charset=utf-8,"
                                    "<head><title>First Page</title></head>"));

  chrome::ExecuteCommand(browser(), IDC_FOCUS_LOCATION);

  host_resolver()->AddRule("*", "127.0.0.1");
  ASSERT_TRUE(embedded_test_server()->Start());
  GURL main_url(embedded_test_server()->GetURL("/english_page.html"));

  OmniboxViewViews* omnibox_view =
      BrowserView::GetBrowserViewForBrowser(browser())->
      toolbar()->location_bar()->omnibox_view();
  omnibox_view->SetUserText(base::UTF8ToUTF16(main_url.spec()),
                            base::UTF8ToUTF16(main_url.spec()),
                            false);

  WinAccessibilityEventMonitor monitor(EVENT_OBJECT_FOCUS, EVENT_OBJECT_FOCUS);
  SendKeyPress(ui::VKEY_RETURN);

  for (;;) {
    DWORD event;
    HWND hwnd;
    UINT role;
    UINT state;
    std::string name;
    monitor.WaitForNextEvent(&event, &hwnd, &role, &state, &name);

    LOG(INFO) << "Got event: "
              << " event=" << event
              << " hwnd=" << hwnd
              << " role=" << role
              << " state=" << state
              << " name=" << name;

    // We should get only focus events.
    EXPECT_EQ(static_cast<DWORD>(EVENT_OBJECT_FOCUS), event);

    // We should get only focus events on document objects. (On a page with
    // JavaScript or autofocus, additional focus events would be expected.)
    EXPECT_EQ(static_cast<DWORD>(ROLE_SYSTEM_DOCUMENT), role);

    // We shouldn't get any events on the first page because from the time
    // we start monitoring, the user has already initiated a load to the
    // second page.
    EXPECT_NE("First Page", name);

    // Finish when we get an event on the second page.
    if (name == "This page is in English") {
      LOG(INFO) << "Got event on second page, finishing test.";
      break;
    }
  }
}