HRESULT ScreenshotCommandHandler::CaptureViewport(BrowserHandle browser) {
LOG(TRACE) << "Entering ScreenshotCommandHandler::CaptureViewport";
HWND content_window_handle = browser->GetContentWindowHandle();
int content_width = 0, content_height = 0;
this->GetWindowDimensions(content_window_handle, &content_width, &content_height);
CaptureWindow(content_window_handle, content_width, content_height);
return S_OK;
}
HRESULT ScreenshotCommandHandler::CaptureFullPage(BrowserHandle browser) {
LOG(TRACE) << "Entering ScreenshotCommandHandler::CaptureFullPage";
HWND ie_window_handle = browser->GetTopLevelWindowHandle();
HWND content_window_handle = browser->GetContentWindowHandle();
CComPtr<IHTMLDocument2> document;
browser->GetDocument(true, &document);
if (!document) {
LOG(WARN) << "Unable to get document from browser. Are you viewing a non-HTML document?";
return E_ABORT;
}
LocationInfo document_info;
bool result = DocumentHost::GetDocumentDimensions(document, &document_info);
if (!result) {
LOG(DEBUG) << "Unable to get document dimensions";
return E_FAIL;
}
LOG(DEBUG) << "Initial document sizes (scrollWidth, scrollHeight) are (w, h): "
<< document_info.width << ", " << document_info.height;
int chrome_width(0);
int chrome_height(0);
this->GetBrowserChromeDimensions(ie_window_handle,
content_window_handle,
&chrome_width,
&chrome_height);
LOG(DEBUG) << "Initial chrome sizes are (w, h): "
<< chrome_width << ", " << chrome_height;
int target_window_width = document_info.width + chrome_width;
int target_window_height = document_info.height + chrome_height;
// For some reason, this technique does not allow the user to resize
// the browser window to greater than SIZE_LIMIT x SIZE_LIMIT. This is
// pretty big, so we'll cap the allowable screenshot size to that.
//
// GDI+ limit after which it may report Generic error for some image types
int SIZE_LIMIT = 65534;
if (target_window_height > SIZE_LIMIT) {
LOG(WARN) << "Required height is greater than limit. Truncating screenshot height.";
target_window_height = SIZE_LIMIT;
document_info.height = target_window_height - chrome_height;
}
if (target_window_width > SIZE_LIMIT) {
LOG(WARN) << "Required width is greater than limit. Truncating screenshot width.";
target_window_width = SIZE_LIMIT;
document_info.width = target_window_width - chrome_width;
}
long original_width = browser->GetWidth();
long original_height = browser->GetHeight();
LOG(DEBUG) << "Initial browser window sizes are (w, h): "
<< original_width << ", " << original_height;
// If the window is already wide enough to accomodate
// the document, don't resize that dimension. Otherwise,
// the window will display a horizontal scroll bar, and
// we need to retain the scrollbar to avoid rerendering
// during the resize, so reduce the target window width
// by two pixels.
if (original_width > target_window_width) {
target_window_width = original_width;
} else {
target_window_width -= 2;
}
// If the window is already tall enough to accomodate
// the document, don't resize that dimension. Otherwise,
// the window will display a vertical scroll bar, and
// we need to retain the scrollbar to avoid rerendering
// during the resize, so reduce the target window height
// by two pixels.
if (original_height > target_window_height) {
target_window_height = original_height;
} else {
target_window_height -= 2;
}
BOOL is_maximized = ::IsZoomed(ie_window_handle);
bool requires_resize = original_width < target_window_width ||
original_height < target_window_height;
if (requires_resize) {
// The resize message is being ignored if the window appears to be
// maximized. There's likely a way to bypass that. The kludgy way
// is to unmaximize the window, then move on with setting the window
// to the dimensions we really want. This is okay because we revert
// back to the original dimensions afterward.
if (is_maximized) {
LOG(DEBUG) << "Window is maximized currently. Demaximizing.";
::ShowWindow(ie_window_handle, SW_SHOWNORMAL);
}
// NOTE: There is a *very* slight chance that resizing the window
// so there are no longer scroll bars to be displayed *might* cause
// layout redraws such that the screenshot does not show the entire
// DOM after the resize. Since we should always be expanding the
// window size, never contracting it, this is a corner case that
// explicitly will *not* be fixed. Any issue reports describing this
// corner case will be closed without action.
RECT ie_window_rect;
::GetWindowRect(ie_window_handle, &ie_window_rect);
::SetWindowPos(ie_window_handle,
NULL,
ie_window_rect.left,
ie_window_rect.top,
target_window_width,
target_window_height,
SWP_NOSENDCHANGING);
}
CaptureWindow(content_window_handle, document_info.width, document_info.height);
if (requires_resize) {
// Restore the browser to the original dimensions.
if (is_maximized) {
::ShowWindow(ie_window_handle, SW_MAXIMIZE);
} else {
browser->SetHeight(original_height);
browser->SetWidth(original_width);
}
}
return S_OK;
}