/*
 *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#include "peerconnection/samples/client/main_wnd.h"

#include "talk/base/common.h"
#include "talk/base/logging.h"

ATOM MainWnd::wnd_class_ = 0;
const wchar_t MainWnd::kClassName[] = L"WebRTC_MainWnd";

// TODO(tommi): declare in header:
std::string GetDefaultServerName();

namespace {
void CalculateWindowSizeForText(HWND wnd, const wchar_t* text,
                                size_t* width, size_t* height) {
  HDC dc = ::GetDC(wnd);
  RECT text_rc = {0};
  ::DrawText(dc, text, -1, &text_rc, DT_CALCRECT | DT_SINGLELINE);
  ::ReleaseDC(wnd, dc);
  RECT client, window;
  ::GetClientRect(wnd, &client);
  ::GetWindowRect(wnd, &window);

  *width = text_rc.right - text_rc.left;
  *width += (window.right - window.left) -
            (client.right - client.left);
  *height = text_rc.bottom - text_rc.top;
  *height += (window.bottom - window.top) -
             (client.bottom - client.top);
}

HFONT GetDefaultFont() {
  static HFONT font = reinterpret_cast<HFONT>(GetStockObject(DEFAULT_GUI_FONT));
  return font;
}

std::string GetWindowText(HWND wnd) {
  char text[MAX_PATH] = {0};
  ::GetWindowTextA(wnd, &text[0], ARRAYSIZE(text));
  return text;
}

void AddListBoxItem(HWND listbox, const std::string& str, LPARAM item_data) {
  LRESULT index = ::SendMessageA(listbox, LB_ADDSTRING, 0,
      reinterpret_cast<LPARAM>(str.c_str()));
  ::SendMessageA(listbox, LB_SETITEMDATA, index, item_data);
}

}  // namespace

MainWnd::MainWnd()
  : ui_(CONNECT_TO_SERVER), wnd_(NULL), edit1_(NULL), edit2_(NULL),
    label1_(NULL), label2_(NULL), button_(NULL), listbox_(NULL),
    destroyed_(false), callback_(NULL), nested_msg_(NULL) {
}

MainWnd::~MainWnd() {
  ASSERT(!IsWindow());
}

bool MainWnd::Create() {
  ASSERT(wnd_ == NULL);
  if (!RegisterWindowClass())
    return false;

  wnd_ = ::CreateWindowExW(WS_EX_OVERLAPPEDWINDOW, kClassName, L"WebRTC",
      WS_OVERLAPPEDWINDOW | WS_VISIBLE | WS_CLIPCHILDREN,
      CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
      NULL, NULL, GetModuleHandle(NULL), this);

  ::SendMessage(wnd_, WM_SETFONT, reinterpret_cast<WPARAM>(GetDefaultFont()),
                TRUE);

  CreateChildWindows();
  SwitchToConnectUI();

  return wnd_ != NULL;
}

bool MainWnd::Destroy() {
  BOOL ret = FALSE;
  if (IsWindow()) {
    ret = ::DestroyWindow(wnd_);
  }

  return ret != FALSE;
}

void MainWnd::RegisterObserver(MainWndCallback* callback) {
  callback_ = callback;
}

bool MainWnd::IsWindow() const {
  return wnd_ && ::IsWindow(wnd_) != FALSE;
}

bool MainWnd::PreTranslateMessage(MSG* msg) {
  bool ret = false;
  if (msg->message == WM_CHAR) {
    if (msg->wParam == VK_TAB) {
      HandleTabbing();
      ret = true;
    } else if (msg->wParam == VK_RETURN) {
      OnDefaultAction();
      ret = true;
    } else if (msg->wParam == VK_ESCAPE) {
      if (callback_) {
        if (ui_ == STREAMING) {
          callback_->DisconnectFromCurrentPeer();
        } else {
          callback_->DisconnectFromServer();
        }
      }
    }
  }
  return ret;
}

void MainWnd::SwitchToConnectUI() {
  ASSERT(IsWindow());
  LayoutPeerListUI(false);
  ui_ = CONNECT_TO_SERVER;
  LayoutConnectUI(true);
  ::SetFocus(edit1_);
}

void MainWnd::SwitchToPeerList(const Peers& peers) {
  LayoutConnectUI(false);

  ::SendMessage(listbox_, LB_RESETCONTENT, 0, 0);

  AddListBoxItem(listbox_, "List of currently connected peers:", -1);
  Peers::const_iterator i = peers.begin();
  for (; i != peers.end(); ++i)
    AddListBoxItem(listbox_, i->second.c_str(), i->first);

  ui_ = LIST_PEERS;
  LayoutPeerListUI(true);
}

void MainWnd::SwitchToStreamingUI() {
  LayoutConnectUI(false);
  LayoutPeerListUI(false);
  ui_ = STREAMING;
}

void MainWnd::OnPaint() {
  PAINTSTRUCT ps;
  ::BeginPaint(handle(), &ps);

  RECT rc;
  ::GetClientRect(handle(), &rc);
  HBRUSH brush = ::CreateSolidBrush(::GetSysColor(COLOR_WINDOW));
  ::FillRect(ps.hdc, &rc, brush);
  ::DeleteObject(brush);

  ::EndPaint(handle(), &ps);
}

void MainWnd::OnDestroyed() {
  PostQuitMessage(0);
}

void MainWnd::OnDefaultAction() {
  if (!callback_)
    return;
  if (ui_ == CONNECT_TO_SERVER) {
    std::string server(GetWindowText(edit1_));
    std::string port_str(GetWindowText(edit2_));
    int port = port_str.length() ? atoi(port_str.c_str()) : 0;
    callback_->StartLogin(server, port);
  } else if (ui_ == LIST_PEERS) {
    LRESULT sel = ::SendMessage(listbox_, LB_GETCURSEL, 0, 0);
    if (sel != LB_ERR) {
      LRESULT peer_id = ::SendMessage(listbox_, LB_GETITEMDATA, sel, 0);
      if (peer_id != -1 && callback_) {
        callback_->ConnectToPeer(peer_id);
      }
    }
  } else {
    MessageBoxA(wnd_, "OK!", "Yeah", MB_OK);
  }
}

bool MainWnd::OnMessage(UINT msg, WPARAM wp, LPARAM lp, LRESULT* result) {
  switch (msg) {
    case WM_ERASEBKGND:
      *result = TRUE;
      return true;
    case WM_PAINT:
      OnPaint();
      return true;
    case WM_SETFOCUS:
      if (ui_ == CONNECT_TO_SERVER) {
        SetFocus(edit1_);
      }
      return true;
    case WM_SIZE:
      if (ui_ == CONNECT_TO_SERVER) {
        LayoutConnectUI(true);
      } else if (ui_ == LIST_PEERS) {
        LayoutPeerListUI(true);
      }
      break;
    case WM_CTLCOLORSTATIC:
      *result = reinterpret_cast<LRESULT>(GetSysColorBrush(COLOR_WINDOW));
      return true;
    case WM_COMMAND:
      if (button_ == reinterpret_cast<HWND>(lp)) {
        if (BN_CLICKED == HIWORD(wp))
          OnDefaultAction();
      } else if (listbox_ == reinterpret_cast<HWND>(lp)) {
        if (LBN_DBLCLK == HIWORD(wp)) {
          OnDefaultAction();
        }
      }
      return true;
  }
  return false;
}

// static
LRESULT CALLBACK MainWnd::WndProc(HWND hwnd, UINT msg, WPARAM wp, LPARAM lp) {
  MainWnd* me = reinterpret_cast<MainWnd*>(
      ::GetWindowLongPtr(hwnd, GWL_USERDATA));
  if (!me && WM_CREATE == msg) {
    CREATESTRUCT* cs = reinterpret_cast<CREATESTRUCT*>(lp);
    me = reinterpret_cast<MainWnd*>(cs->lpCreateParams);
    me->wnd_ = hwnd;
    ::SetWindowLongPtr(hwnd, GWL_USERDATA, reinterpret_cast<LONG_PTR>(me));
  }

  LRESULT result = 0;
  if (me) {
    void* prev_nested_msg = me->nested_msg_;
    me->nested_msg_ = &msg;

    bool handled = me->OnMessage(msg, wp, lp, &result);
    if (WM_NCDESTROY == msg) {
      me->destroyed_ = true;
    } else if (!handled) {
      result = ::DefWindowProc(hwnd, msg, wp, lp);
    }

    if (me->destroyed_ && prev_nested_msg == NULL) {
      me->OnDestroyed();
      me->wnd_ = NULL;
      me->destroyed_ = false;
    }

    me->nested_msg_ = prev_nested_msg;
  } else {
    result = ::DefWindowProc(hwnd, msg, wp, lp);
  }

  return result;
}

// static
bool MainWnd::RegisterWindowClass() {
  if (wnd_class_)
    return true;

  WNDCLASSEX wcex = { sizeof(WNDCLASSEX) };
  wcex.style = CS_DBLCLKS;
  wcex.hInstance = GetModuleHandle(NULL);
  wcex.hbrBackground = reinterpret_cast<HBRUSH>(COLOR_WINDOW + 1);
  wcex.hCursor = ::LoadCursor(NULL, IDC_ARROW);
  wcex.lpfnWndProc = &WndProc;
  wcex.lpszClassName = kClassName;
  wnd_class_ = ::RegisterClassEx(&wcex);
  ASSERT(wnd_class_);
  return wnd_class_ != 0;
}

void MainWnd::CreateChildWindow(HWND* wnd, MainWnd::ChildWindowID id,
                                const wchar_t* class_name, DWORD control_style,
                                DWORD ex_style) {
  if (::IsWindow(*wnd))
    return;

  // Child windows are invisible at first, and shown after being resized.
  DWORD style = WS_CHILD | control_style;
  *wnd = ::CreateWindowEx(ex_style, class_name, L"", style,
                          100, 100, 100, 100, wnd_,
                          reinterpret_cast<HMENU>(id),
                          GetModuleHandle(NULL), NULL);
  ASSERT(::IsWindow(*wnd));
  ::SendMessage(*wnd, WM_SETFONT, reinterpret_cast<WPARAM>(GetDefaultFont()),
                TRUE);
}

void MainWnd::CreateChildWindows() {
  // Create the child windows in tab order.
  CreateChildWindow(&label1_, LABEL1_ID, L"Static", ES_CENTER | ES_READONLY, 0);
  CreateChildWindow(&edit1_, EDIT_ID, L"Edit",
                    ES_LEFT | ES_NOHIDESEL | WS_TABSTOP, WS_EX_CLIENTEDGE);
  CreateChildWindow(&label2_, LABEL2_ID, L"Static", ES_CENTER | ES_READONLY, 0);
  CreateChildWindow(&edit2_, EDIT_ID, L"Edit",
                    ES_LEFT | ES_NOHIDESEL | WS_TABSTOP, WS_EX_CLIENTEDGE);
  CreateChildWindow(&button_, BUTTON_ID, L"Button", BS_CENTER | WS_TABSTOP, 0);

  CreateChildWindow(&listbox_, LISTBOX_ID, L"ListBox",
                    LBS_HASSTRINGS | LBS_NOTIFY, WS_EX_CLIENTEDGE);

  ::SetWindowTextA(edit1_, GetDefaultServerName().c_str());
  ::SetWindowTextA(edit2_, "8888");
}

void MainWnd::LayoutConnectUI(bool show) {
  struct Windows {
    HWND wnd;
    const wchar_t* text;
    size_t width;
    size_t height;
  } windows[] = {
    { label1_, L"Server" },
    { edit1_, L"XXXyyyYYYgggXXXyyyYYYggg" },
    { label2_, L":" },
    { edit2_, L"XyXyX" },
    { button_, L"Connect" },
  };

  if (show) {
    const size_t kSeparator = 5;
    size_t total_width = (ARRAYSIZE(windows) - 1) * kSeparator;

    for (size_t i = 0; i < ARRAYSIZE(windows); ++i) {
      CalculateWindowSizeForText(windows[i].wnd, windows[i].text,
                                 &windows[i].width, &windows[i].height);
      total_width += windows[i].width;
    }

    RECT rc;
    ::GetClientRect(wnd_, &rc);
    size_t x = (rc.right / 2) - (total_width / 2);
    size_t y = rc.bottom / 2;
    for (size_t i = 0; i < ARRAYSIZE(windows); ++i) {
      size_t top = y - (windows[i].height / 2);
      ::MoveWindow(windows[i].wnd, x, top, windows[i].width, windows[i].height,
                   TRUE);
      x += kSeparator + windows[i].width;
      if (windows[i].text[0] != 'X')
        ::SetWindowText(windows[i].wnd, windows[i].text);
      ::ShowWindow(windows[i].wnd, SW_SHOWNA);
    }
  } else {
    for (size_t i = 0; i < ARRAYSIZE(windows); ++i) {
      ::ShowWindow(windows[i].wnd, SW_HIDE);
    }
  }
}

void MainWnd::LayoutPeerListUI(bool show) {
  if (show) {
    RECT rc;
    ::GetClientRect(wnd_, &rc);
    ::MoveWindow(listbox_, 0, 0, rc.right, rc.bottom, TRUE);
    ::ShowWindow(listbox_, SW_SHOWNA);
  } else {
    ::ShowWindow(listbox_, SW_HIDE);
  }
}

void MainWnd::HandleTabbing() {
  bool shift = ((::GetAsyncKeyState(VK_SHIFT) & 0x8000) != 0);
  UINT next_cmd = shift ? GW_HWNDPREV : GW_HWNDNEXT;
  UINT loop_around_cmd = shift ? GW_HWNDLAST : GW_HWNDFIRST;
  HWND focus = GetFocus(), next;
  do {
    next = ::GetWindow(focus, next_cmd);
    if (IsWindowVisible(next) &&
        (GetWindowLong(next, GWL_STYLE) & WS_TABSTOP)) {
      break;
    }

    if (!next) {
      next = ::GetWindow(focus, loop_around_cmd);
      if (IsWindowVisible(next) &&
          (GetWindowLong(next, GWL_STYLE) & WS_TABSTOP)) {
        break;
      }
    }
    focus = next;
  } while (true);
  ::SetFocus(next);
}