// Copyright (c) 2012 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 "ui/aura/remote_window_tree_host_win.h"

#include <windows.h>

#include <algorithm>

#include "base/message_loop/message_loop.h"
#include "ipc/ipc_message.h"
#include "ipc/ipc_sender.h"
#include "ui/aura/client/cursor_client.h"
#include "ui/aura/window_event_dispatcher.h"
#include "ui/aura/window_property.h"
#include "ui/base/cursor/cursor_loader_win.h"
#include "ui/base/ime/composition_text.h"
#include "ui/base/ime/input_method.h"
#include "ui/base/ime/remote_input_method_win.h"
#include "ui/base/ime/text_input_client.h"
#include "ui/base/view_prop.h"
#include "ui/events/event_utils.h"
#include "ui/events/keycodes/keyboard_code_conversion_win.h"
#include "ui/gfx/geometry/insets.h"
#include "ui/gfx/win/dpi.h"
#include "ui/metro_viewer/metro_viewer_messages.h"

namespace aura {

namespace {

const char* kWindowTreeHostWinKey = "__AURA_REMOTE_WINDOW_TREE_HOST_WIN__";

// Sets the keystate for the virtual key passed in to down or up.
void SetKeyState(uint8* key_states, bool key_down, uint32 virtual_key_code) {
  DCHECK(key_states);

  if (key_down)
    key_states[virtual_key_code] |= 0x80;
  else
    key_states[virtual_key_code] &= 0x7F;
}

// Sets the keyboard states for the Shift/Control/Alt/Caps lock keys.
void SetVirtualKeyStates(uint32 flags) {
  uint8 keyboard_state[256] = {0};
  ::GetKeyboardState(keyboard_state);

  SetKeyState(keyboard_state, !!(flags & ui::EF_SHIFT_DOWN), VK_SHIFT);
  SetKeyState(keyboard_state, !!(flags & ui::EF_CONTROL_DOWN), VK_CONTROL);
  SetKeyState(keyboard_state, !!(flags & ui::EF_ALT_DOWN), VK_MENU);
  SetKeyState(keyboard_state, !!(flags & ui::EF_CAPS_LOCK_DOWN), VK_CAPITAL);
  SetKeyState(keyboard_state, !!(flags & ui::EF_LEFT_MOUSE_BUTTON), VK_LBUTTON);
  SetKeyState(keyboard_state, !!(flags & ui::EF_RIGHT_MOUSE_BUTTON),
              VK_RBUTTON);
  SetKeyState(keyboard_state, !!(flags & ui::EF_MIDDLE_MOUSE_BUTTON),
              VK_MBUTTON);

  ::SetKeyboardState(keyboard_state);
}

void FillCompositionText(
    const base::string16& text,
    int32 selection_start,
    int32 selection_end,
    const std::vector<metro_viewer::UnderlineInfo>& underlines,
    ui::CompositionText* composition_text) {
  composition_text->Clear();
  composition_text->text = text;
  composition_text->selection.set_start(selection_start);
  composition_text->selection.set_end(selection_end);
  composition_text->underlines.resize(underlines.size());
  for (size_t i = 0; i < underlines.size(); ++i) {
    composition_text->underlines[i].start_offset = underlines[i].start_offset;
    composition_text->underlines[i].end_offset = underlines[i].end_offset;
    composition_text->underlines[i].color = SK_ColorBLACK;
    composition_text->underlines[i].thick = underlines[i].thick;
    composition_text->underlines[i].background_color = SK_ColorTRANSPARENT;
  }
}

}  // namespace

RemoteWindowTreeHostWin* g_instance = NULL;

// static
RemoteWindowTreeHostWin* RemoteWindowTreeHostWin::Instance() {
  return g_instance;
}

RemoteWindowTreeHostWin::RemoteWindowTreeHostWin()
    : remote_window_(NULL),
      host_(NULL),
      ignore_mouse_moves_until_set_cursor_ack_(0),
      event_flags_(0),
      window_size_(GetSystemMetrics(SM_CXSCREEN),
                   GetSystemMetrics(SM_CYSCREEN)) {
  CHECK(!g_instance);
  g_instance = this;
  prop_.reset(new ui::ViewProp(NULL, kWindowTreeHostWinKey, this));
  CreateCompositor();
  OnAcceleratedWidgetAvailable();
}

RemoteWindowTreeHostWin::~RemoteWindowTreeHostWin() {
  DestroyCompositor();
  DestroyDispatcher();
  DCHECK_EQ(g_instance, this);
  g_instance = NULL;
}

// static
bool RemoteWindowTreeHostWin::IsValid() {
  return Instance()->remote_window_ != NULL;
}

void RemoteWindowTreeHostWin::SetRemoteWindowHandle(HWND remote_window) {
  remote_window_ = remote_window;
}

void RemoteWindowTreeHostWin::Connected(IPC::Sender* host) {
  CHECK(host_ == NULL);
  DCHECK(remote_window_);
  host_ = host;
  // Recreate the compositor for the target surface represented by the
  // remote_window HWND.
  CreateCompositor();
  OnAcceleratedWidgetAvailable();
  InitCompositor();
}

void RemoteWindowTreeHostWin::Disconnected() {
  // Don't CHECK here, Disconnected is called on a channel error which can
  // happen before we're successfully Connected.
  if (!host_)
    return;
  ui::RemoteInputMethodPrivateWin* remote_input_method_private =
      GetRemoteInputMethodPrivate();
  if (remote_input_method_private)
    remote_input_method_private->SetRemoteDelegate(NULL);
  host_ = NULL;
  remote_window_ = NULL;
}

bool RemoteWindowTreeHostWin::OnMessageReceived(const IPC::Message& message) {
  bool handled = true;
  IPC_BEGIN_MESSAGE_MAP(RemoteWindowTreeHostWin, message)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_MouseMoved, OnMouseMoved)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_MouseButton, OnMouseButton)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_KeyDown, OnKeyDown)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_KeyUp, OnKeyUp)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_Character, OnChar)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_WindowActivated,
                        OnWindowActivated)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_EdgeGesture, OnEdgeGesture)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_TouchDown,
                        OnTouchDown)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_TouchUp,
                        OnTouchUp)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_TouchMoved,
                        OnTouchMoved)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_SetCursorPosAck,
                        OnSetCursorPosAck)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_ImeCandidatePopupChanged,
                        OnImeCandidatePopupChanged)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_ImeCompositionChanged,
                        OnImeCompositionChanged)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_ImeTextCommitted,
                        OnImeTextCommitted)
    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_ImeInputSourceChanged,
                        OnImeInputSourceChanged)
    IPC_MESSAGE_UNHANDLED(handled = false)
  IPC_END_MESSAGE_MAP()
  return handled;
}

void RemoteWindowTreeHostWin::HandleOpenURLOnDesktop(
    const base::FilePath& shortcut,
    const base::string16& url) {
  if (!host_)
    return;
  host_->Send(new MetroViewerHostMsg_OpenURLOnDesktop(shortcut, url));
}

void RemoteWindowTreeHostWin::HandleWindowSizeChanged(uint32 width,
                                                      uint32 height) {
  SetBounds(gfx::Rect(0, 0, width, height));
}

bool RemoteWindowTreeHostWin::IsForegroundWindow() {
  return ::GetForegroundWindow() == remote_window_;
}

Window* RemoteWindowTreeHostWin::GetAshWindow() {
  return window();
}

ui::EventSource* RemoteWindowTreeHostWin::GetEventSource() {
  return this;
}

gfx::AcceleratedWidget RemoteWindowTreeHostWin::GetAcceleratedWidget() {
  if (remote_window_)
    return remote_window_;
  // Getting here should only happen for ash_unittests.exe and related code.
  return ::GetDesktopWindow();
}

void RemoteWindowTreeHostWin::ShowImpl() {
  ui::RemoteInputMethodPrivateWin* remote_input_method_private =
      GetRemoteInputMethodPrivate();
  if (remote_input_method_private)
    remote_input_method_private->SetRemoteDelegate(this);
}

void RemoteWindowTreeHostWin::HideImpl() {
  NOTIMPLEMENTED();
}

gfx::Rect RemoteWindowTreeHostWin::GetBounds() const {
  return gfx::Rect(window_size_);
}

void RemoteWindowTreeHostWin::SetBounds(const gfx::Rect& bounds) {
  window_size_ = bounds.size();
  OnHostResized(bounds.size());
}

gfx::Point RemoteWindowTreeHostWin::GetLocationOnNativeScreen() const {
  return gfx::Point(0, 0);
}

void RemoteWindowTreeHostWin::SetCapture() {
}

void RemoteWindowTreeHostWin::ReleaseCapture() {
}

void RemoteWindowTreeHostWin::SetCursorNative(gfx::NativeCursor native_cursor) {
  if (!host_)
    return;
  host_->Send(
      new MetroViewerHostMsg_SetCursor(uint64(native_cursor.platform())));
}

void RemoteWindowTreeHostWin::MoveCursorToNative(const gfx::Point& location) {
  VLOG(1) << "In MoveCursorTo: " << location.x() << ", " << location.y();
  if (!host_)
    return;

  // This function can be called in cases like when the mouse cursor is
  // restricted within a viewport (For e.g. LockCursor) which assumes that
  // subsequent mouse moves would be received starting with the new cursor
  // coordinates. This is a challenge for Windows ASH for the reasons
  // outlined below.
  // Other cases which don't expect this behavior should continue to work
  // without issues.

  // The mouse events are received by the viewer process and sent to the
  // browser. If we invoke the SetCursor API here we continue to receive
  // mouse messages from the viewer which were posted before the SetCursor
  // API executes which messes up the state in the browser. To workaround
  // this we invoke the SetCursor API in the viewer process and ignore
  // mouse messages until we received an ACK from the viewer indicating that
  // the SetCursor operation completed.
  ignore_mouse_moves_until_set_cursor_ack_++;
  VLOG(1) << "In MoveCursorTo. Sending IPC";
  host_->Send(new MetroViewerHostMsg_SetCursorPos(location.x(), location.y()));
}

void RemoteWindowTreeHostWin::OnCursorVisibilityChangedNative(bool show) {
  NOTIMPLEMENTED();
}

void RemoteWindowTreeHostWin::CancelComposition() {
  if (!host_)
    return;
  host_->Send(new MetroViewerHostMsg_ImeCancelComposition);
}

void RemoteWindowTreeHostWin::OnTextInputClientUpdated(
    const std::vector<int32>& input_scopes,
    const std::vector<gfx::Rect>& composition_character_bounds) {
  if (!host_)
    return;
  std::vector<metro_viewer::CharacterBounds> character_bounds;
  for (size_t i = 0; i < composition_character_bounds.size(); ++i) {
    const gfx::Rect& rect = composition_character_bounds[i];
    metro_viewer::CharacterBounds bounds;
    bounds.left = rect.x();
    bounds.top = rect.y();
    bounds.right = rect.right();
    bounds.bottom = rect.bottom();
    character_bounds.push_back(bounds);
  }
  host_->Send(new MetroViewerHostMsg_ImeTextInputClientUpdated(
      input_scopes, character_bounds));
}

gfx::Point PointFromNativeEvent(int32 x, int32 y) {
  static float scale_factor = gfx::GetDPIScale();
  gfx::Point result( x * scale_factor, y * scale_factor);
  return result;
}

void RemoteWindowTreeHostWin::OnMouseMoved(int32 x, int32 y, int32 flags) {
  if (ignore_mouse_moves_until_set_cursor_ack_)
    return;

  gfx::Point location = PointFromNativeEvent(x, y);
  ui::MouseEvent event(ui::ET_MOUSE_MOVED, location, location,
                       ui::EventTimeForNow(), flags, 0);
  SendEventToProcessor(&event);
}

void RemoteWindowTreeHostWin::OnMouseButton(
    const MetroViewerHostMsg_MouseButtonParams& params) {
  gfx::Point location = PointFromNativeEvent(params.x, params.y);
  ui::MouseEvent mouse_event(
      params.event_type, location, location, ui::EventTimeForNow(),
      static_cast<int>(params.flags), static_cast<int>(params.changed_button));

  SetEventFlags(params.flags | key_event_flags());
  if (params.event_type == ui::ET_MOUSEWHEEL) {
    int x_offset = params.is_horizontal_wheel ? params.extra : 0;
    int y_offset = !params.is_horizontal_wheel ? params.extra : 0;
    ui::MouseWheelEvent wheel_event(mouse_event, x_offset, y_offset);
    SendEventToProcessor(&wheel_event);
  } else if (params.event_type == ui::ET_MOUSE_PRESSED) {
    // TODO(shrikant): Ideally modify code in event.cc by adding automatic
    // tracking of double clicks in synthetic MouseEvent constructor code.
    // Non-synthetic MouseEvent constructor code does automatically track
    // this. Need to use some caution while modifying synthetic constructor
    // as many tests and other code paths depend on it and apparently
    // specifically depend on non implicit tracking of previous mouse event.
    if (last_mouse_click_event_ &&
        ui::MouseEvent::IsRepeatedClickEvent(mouse_event,
                                             *last_mouse_click_event_)) {
      mouse_event.SetClickCount(2);
    } else {
      mouse_event.SetClickCount(1);
    }
    last_mouse_click_event_ .reset(new ui::MouseEvent(mouse_event));
    SendEventToProcessor(&mouse_event);
  } else {
    SendEventToProcessor(&mouse_event);
  }
}

void RemoteWindowTreeHostWin::OnKeyDown(uint32 vkey,
                                        uint32 repeat_count,
                                        uint32 scan_code,
                                        uint32 flags) {
  DispatchKeyboardMessage(ui::ET_KEY_PRESSED, vkey, repeat_count, scan_code,
                          flags, false);
}

void RemoteWindowTreeHostWin::OnKeyUp(uint32 vkey,
                                      uint32 repeat_count,
                                      uint32 scan_code,
                                      uint32 flags) {
  DispatchKeyboardMessage(ui::ET_KEY_RELEASED, vkey, repeat_count, scan_code,
                          flags, false);
}

void RemoteWindowTreeHostWin::OnChar(uint32 key_code,
                                     uint32 repeat_count,
                                     uint32 scan_code,
                                     uint32 flags) {
  DispatchKeyboardMessage(ui::ET_KEY_PRESSED, key_code, repeat_count,
                          scan_code, flags, true);
}

void RemoteWindowTreeHostWin::OnWindowActivated(bool repaint) {
  OnHostActivated();
  if (repaint && compositor())
    compositor()->ScheduleFullRedraw();
}

void RemoteWindowTreeHostWin::OnEdgeGesture() {
  ui::GestureEvent event(
      0,
      0,
      0,
      ui::EventTimeForNow(),
      ui::GestureEventDetails(ui::ET_GESTURE_WIN8_EDGE_SWIPE));
  SendEventToProcessor(&event);
}

void RemoteWindowTreeHostWin::OnTouchDown(int32 x,
                                          int32 y,
                                          uint64 timestamp,
                                          uint32 pointer_id) {
  gfx::Point location = PointFromNativeEvent(x, y);
  ui::TouchEvent event(ui::ET_TOUCH_PRESSED,
                       location,
                       pointer_id,
                       base::TimeDelta::FromMicroseconds(timestamp));
  SendEventToProcessor(&event);
}

void RemoteWindowTreeHostWin::OnTouchUp(int32 x,
                                        int32 y,
                                        uint64 timestamp,
                                        uint32 pointer_id) {
  gfx::Point location = PointFromNativeEvent(x, y);
  ui::TouchEvent event(ui::ET_TOUCH_RELEASED,
                       location,
                       pointer_id,
                       base::TimeDelta::FromMicroseconds(timestamp));
  SendEventToProcessor(&event);
}

void RemoteWindowTreeHostWin::OnTouchMoved(int32 x,
                                           int32 y,
                                           uint64 timestamp,
                                           uint32 pointer_id) {
  gfx::Point location = PointFromNativeEvent(x, y);
  ui::TouchEvent event(ui::ET_TOUCH_MOVED,
                       location,
                       pointer_id,
                       base::TimeDelta::FromMicroseconds(timestamp));
  SendEventToProcessor(&event);
}

void RemoteWindowTreeHostWin::OnSetCursorPosAck() {
  DCHECK_GT(ignore_mouse_moves_until_set_cursor_ack_, 0);
  ignore_mouse_moves_until_set_cursor_ack_--;
}

ui::RemoteInputMethodPrivateWin*
RemoteWindowTreeHostWin::GetRemoteInputMethodPrivate() {
  return ui::RemoteInputMethodPrivateWin::Get(GetInputMethod());
}

void RemoteWindowTreeHostWin::OnImeCandidatePopupChanged(bool visible) {
  ui::RemoteInputMethodPrivateWin* remote_input_method_private =
      GetRemoteInputMethodPrivate();
  if (!remote_input_method_private)
    return;
  remote_input_method_private->OnCandidatePopupChanged(visible);
}

void RemoteWindowTreeHostWin::OnImeCompositionChanged(
    const base::string16& text,
    int32 selection_start,
    int32 selection_end,
    const std::vector<metro_viewer::UnderlineInfo>& underlines) {
  ui::RemoteInputMethodPrivateWin* remote_input_method_private =
      GetRemoteInputMethodPrivate();
  if (!remote_input_method_private)
    return;
  ui::CompositionText composition_text;
  FillCompositionText(
      text, selection_start, selection_end, underlines, &composition_text);
  remote_input_method_private->OnCompositionChanged(composition_text);
}

void RemoteWindowTreeHostWin::OnImeTextCommitted(const base::string16& text) {
  ui::RemoteInputMethodPrivateWin* remote_input_method_private =
      GetRemoteInputMethodPrivate();
  if (!remote_input_method_private)
    return;
  remote_input_method_private->OnTextCommitted(text);
}

void RemoteWindowTreeHostWin::OnImeInputSourceChanged(uint16 language_id,
                                                      bool is_ime) {
  ui::RemoteInputMethodPrivateWin* remote_input_method_private =
      GetRemoteInputMethodPrivate();
  if (!remote_input_method_private)
    return;
  remote_input_method_private->OnInputSourceChanged(language_id, is_ime);
}

void RemoteWindowTreeHostWin::DispatchKeyboardMessage(ui::EventType type,
                                                      uint32 vkey,
                                                      uint32 repeat_count,
                                                      uint32 scan_code,
                                                      uint32 flags,
                                                      bool is_character) {
  SetEventFlags(flags | mouse_event_flags());
  if (base::MessageLoop::current()->IsNested()) {
    int index = (flags & ui::EF_ALT_DOWN) ? 1 : 0;
    const int char_message[] = {WM_CHAR, WM_SYSCHAR};
    const int keydown_message[] = {WM_KEYDOWN, WM_SYSKEYDOWN};
    const int keyup_message[] = {WM_KEYUP, WM_SYSKEYUP};
    uint32 message = is_character
                         ? char_message[index]
                         : (type == ui::ET_KEY_PRESSED ? keydown_message[index]
                                                       : keyup_message[index]);
    ::PostThreadMessage(::GetCurrentThreadId(),
                        message,
                        vkey,
                        repeat_count | scan_code >> 15);
  } else if (is_character) {
    ui::KeyEvent event(static_cast<base::char16>(vkey),
                       ui::KeyboardCodeForWindowsKeyCode(vkey),
                       flags);
    SendEventToProcessor(&event);
  } else {
    ui::KeyEvent event(type,
                       ui::KeyboardCodeForWindowsKeyCode(vkey),
                       flags);
    SendEventToProcessor(&event);
  }
}

void RemoteWindowTreeHostWin::SetEventFlags(uint32 flags) {
  if (flags == event_flags_)
    return;
  event_flags_ = flags;
  SetVirtualKeyStates(event_flags_);
}

}  // namespace aura