/* 9 april 2015 */
#include "uipriv_windows.hpp"

WCHAR *windowTextAndLen(HWND hwnd, LRESULT *len)
{
   WCHAR *text = NULL;
   LRESULT n   = SendMessageW(hwnd, WM_GETTEXTLENGTH, 0, 0);

   if (len != NULL)
      *len = n;
   /* WM_GETTEXTLENGTH does not include the null terminator */
   text = (WCHAR *) uiAlloc((n + 1) * sizeof (WCHAR), "WCHAR[]");
   /* note the comparison: the size includes the 
    * null terminator, but the return does not */
   if (GetWindowTextW(hwnd, text, n + 1) != n)
   {
      logLastError(L"error getting window text");
      /* on error, return an empty string to be safe */
      *text = L'\0';
      if (len != NULL)
         *len = 0;
   }
   return text;
}

WCHAR *windowText(HWND hwnd)
{
   return windowTextAndLen(hwnd, NULL);
}

void setWindowText(HWND hwnd, WCHAR *wtext)
{
   if (SetWindowTextW(hwnd, wtext) == 0)
      logLastError(L"error setting window text");
}

void uiFreeText(char *text)
{
	uiFree(text);
}

int uiWindowsWindowTextWidth(HWND hwnd)
{
   LRESULT len;
   HDC dc;
   HFONT prevfont;
   SIZE size;
   WCHAR *text = windowTextAndLen(hwnd, &len);

   size.cx = 0;
   size.cy = 0;

   if (len == 0)		/* no text; nothing to do */
      goto noTextOrError;

   /* now we can do the calculations */
   dc = GetDC(hwnd);
   if (dc == NULL)
   {
      logLastError(L"error getting DC");
      /* on any error, assume no text */
      goto noTextOrError;
   }
   prevfont = (HFONT) SelectObject(dc, hMessageFont);
   if (prevfont == NULL)
   {
      logLastError(L"error loading control font into device context");
      ReleaseDC(hwnd, dc);
      goto noTextOrError;
   }
   if (GetTextExtentPoint32W(dc, text, len, &size) == 0)
   {
      logLastError(L"error getting text extent point");
      /* continue anyway, assuming size is 0 */
      size.cx = 0;
      size.cy = 0;
   }
   /* continue on errors; we got what we want */
   if (SelectObject(dc, prevfont) != hMessageFont)
      logLastError(L"error restoring previous font into device context");
   if (ReleaseDC(hwnd, dc) == 0)
      logLastError(L"error releasing DC");

   uiFree(text);
   return size.cx;

noTextOrError:
   uiFree(text);
   return 0;
}

char *uiWindowsWindowText(HWND hwnd)
{
	WCHAR *wtext = windowText(hwnd);
	char *text   = toUTF8(wtext);
	uiFree(wtext);
	return text;
}

void uiWindowsSetWindowText(HWND hwnd, const char *text)
{
	WCHAR *wtext = toUTF16(text);
	setWindowText(hwnd, wtext);
	uiFree(wtext);
}