webview_universal/windows/utils.cc

//
// Created by yangbin on 2021/11/11.
//

#include <windows.h>

#include "utils.h"

#include <memory>
#include <set>


namespace webview_window {

void ClipOrCenterRectToMonitor(LPRECT prc, UINT flags) {
  HMONITOR hMonitor;
  MONITORINFO mi;
  RECT rc;
  int w = prc->right - prc->left;
  int h = prc->bottom - prc->top;

  //
  // get the nearest monitor to the passed rect.
  //
  hMonitor = MonitorFromRect(prc, MONITOR_DEFAULTTONEAREST);

  //
  // get the work area or entire monitor rect.
  //
  mi.cbSize = sizeof(mi);
  GetMonitorInfo(hMonitor, &mi);

  if (flags & MONITOR_WORKAREA)
    rc = mi.rcWork;
  else
    rc = mi.rcMonitor;

  //
  // center or clip the passed rect to the monitor rect
  //
  if (flags & MONITOR_CENTER) {
    prc->left = rc.left + (rc.right - rc.left - w) / 2;
    prc->top = rc.top + (rc.bottom - rc.top - h) / 2;
    prc->right = prc->left + w;
    prc->bottom = prc->top + h;
  } else {
    prc->left = max(rc.left, min(rc.right - w, prc->left));
    prc->top = max(rc.top, min(rc.bottom - h, prc->top));
    prc->right = prc->left + w;
    prc->bottom = prc->top + h;
  }
}

void ClipOrCenterWindowToMonitor(HWND hwnd, UINT flags) {
  RECT rc;
  GetWindowRect(hwnd, &rc);
  ClipOrCenterRectToMonitor(&rc, flags);
  SetWindowPos(hwnd, nullptr, rc.left, rc.top, 0, 0, SWP_NOSIZE | SWP_NOZORDER | SWP_NOACTIVATE);
}

bool SetWindowBackgroundTransparent(HWND hwnd) {
  // TODO
  return false;
}

static std::unique_ptr<std::set<LPCWSTR>> class_registered_;

const wchar_t *RegisterWindowClass(LPCWSTR class_name, WNDPROC wnd_proc) {
  if (!class_registered_ || class_registered_->count(class_name) == 0) {
    if (!class_registered_) {
      class_registered_ = std::make_unique<std::set<LPCWSTR>>();
    }
    WNDCLASS window_class{};
    window_class.hCursor = LoadCursor(nullptr, IDC_ARROW);
    window_class.lpszClassName = class_name;
    window_class.style = CS_HREDRAW | CS_VREDRAW;
    window_class.cbClsExtra = 0;
    window_class.cbWndExtra = 0;
    window_class.hInstance = GetModuleHandle(nullptr);
    window_class.hIcon =
        LoadIcon(window_class.hInstance, IDI_APPLICATION);
    window_class.hbrBackground = (HBRUSH) (COLOR_WINDOW + 1);
    window_class.lpszMenuName = nullptr;
    window_class.lpfnWndProc = wnd_proc;
    RegisterClass(&window_class);
    class_registered_->insert(class_name);
  }
  return class_name;
}

void UnregisterWindowClass(LPCWSTR class_name) {
  if (!class_registered_) {
    return;
  }
  class_registered_->erase(class_name);
  UnregisterClass(class_name, nullptr);
}

}  // namespace webview_window