#include "StdAfx.h"
#include "UIShadow.h"
#include "math.h"
#include "crtdbg.h"

namespace DuiLib
{

const TCHAR *strWndClassName = _T("PerryShadowWnd");
bool CShadowUI::s_bHasInit = FALSE;

CShadowUI::CShadowUI(void)
: m_hWnd((HWND)NULL)
, m_OriParentProc(NULL)
, m_Status(0)
, m_nDarkness(150)
, m_nSharpness(5)
, m_nSize(0)
, m_nxOffset(0)
, m_nyOffset(0)
, m_Color(RGB(0, 0, 0))
, m_WndSize(0)
, m_bUpdate(false)
, m_bIsImageMode(false)
, m_bIsShowShadow(false)
, m_bIsDisableShadow(false)
{
	::ZeroMemory(&m_rcShadowCorner, sizeof(RECT));
}

CShadowUI::~CShadowUI(void)
{
}

bool CShadowUI::Initialize(HINSTANCE hInstance)
{
	if (s_bHasInit)
		return false;

	// Register window class for shadow window
	WNDCLASSEX wcex;

	memset(&wcex, 0, sizeof(wcex));

	wcex.cbSize = sizeof(WNDCLASSEX); 
	wcex.style			= CS_HREDRAW | CS_VREDRAW;
	wcex.lpfnWndProc	= DefWindowProc;
	wcex.cbClsExtra		= 0;
	wcex.cbWndExtra		= 0;
	wcex.hInstance		= hInstance;
	wcex.hIcon			= NULL;
	wcex.hCursor		= LoadCursor(NULL, IDC_ARROW);
	wcex.hbrBackground	= (HBRUSH)(COLOR_WINDOW+1);
	wcex.lpszMenuName	= NULL;
	wcex.lpszClassName	= strWndClassName;
	wcex.hIconSm		= NULL;

	RegisterClassEx(&wcex);

	s_bHasInit = true;
	return true;
}

void CShadowUI::Create(CPaintManagerUI* pPaintManager)
{
	if(!m_bIsShowShadow)
		return;

	// Already initialized
	_ASSERT(CPaintManagerUI::GetInstance() != INVALID_HANDLE_VALUE);
	_ASSERT(pPaintManager != NULL);
	m_pManager = pPaintManager;
	HWND hParentWnd = m_pManager->GetPaintWindow();
	// Add parent window - shadow pair to the map
	_ASSERT(GetShadowMap().find(hParentWnd) == GetShadowMap().end());	// Only one shadow for each window
	GetShadowMap()[hParentWnd] = this;

	// Determine the initial show state of shadow according to parent window's state
	LONG lParentStyle = GetWindowLongPtr(hParentWnd, GWL_STYLE);

	// Create the shadow window
	LONG styleValue = lParentStyle & WS_CAPTION;
	m_hWnd = CreateWindowEx(WS_EX_LAYERED | WS_EX_TRANSPARENT, strWndClassName, NULL,
		/*WS_VISIBLE | */styleValue | WS_POPUPWINDOW,
		CW_USEDEFAULT, 0, 0, 0, hParentWnd, NULL, CPaintManagerUI::GetInstance(), NULL);

	if(!(WS_VISIBLE & lParentStyle))	// Parent invisible
		m_Status = SS_ENABLED;
	else if((WS_MAXIMIZE | WS_MINIMIZE) & lParentStyle)	// Parent visible but does not need shadow
		m_Status = SS_ENABLED | SS_PARENTVISIBLE;
	else	// Show the shadow
	{
		m_Status = SS_ENABLED | SS_VISABLE | SS_PARENTVISIBLE;
		::ShowWindow(m_hWnd, SW_SHOWNOACTIVATE);
		Update(hParentWnd);
	}

	// Replace the original WndProc of parent window to steal messages
	m_OriParentProc = GetWindowLongPtr(hParentWnd, GWLP_WNDPROC);

#pragma warning(disable: 4311)	// temporrarily disable the type_cast warning in Win32
	SetWindowLongPtr(hParentWnd, GWLP_WNDPROC, (LONG_PTR)ParentProc);
#pragma warning(default: 4311)

}

std::map<HWND, CShadowUI *>& CShadowUI::GetShadowMap()
{
	static std::map<HWND, CShadowUI *> s_Shadowmap;
	return s_Shadowmap;
}

LRESULT CALLBACK CShadowUI::ParentProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	_ASSERT(GetShadowMap().find(hwnd) != GetShadowMap().end());	// Shadow must have been attached

	CShadowUI *pThis = GetShadowMap()[hwnd];
	if (pThis->IsDisableShadow()) {
		return CallWindowProc((WNDPROC)pThis->m_OriParentProc, hwnd, uMsg, wParam, lParam);
	}

	switch(uMsg)
	{
	case WM_ACTIVATEAPP:
		{
			if(!IsWindowEnabled(hwnd)) break;
			::SetWindowPos(pThis->m_hWnd, hwnd, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE | SWP_NOACTIVATE | SWP_NOREDRAW);
			break;
		}
	case WM_NCACTIVATE:
		{
			if(!IsWindowEnabled(hwnd)) break;
			::SetWindowPos(pThis->m_hWnd, hwnd, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE | SWP_NOACTIVATE | SWP_NOREDRAW);
			break;
		}
	case WM_WINDOWPOSCHANGED:
		{
			RECT WndRect;
			LPWINDOWPOS pWndPos;
			pWndPos = (LPWINDOWPOS)lParam;
			GetWindowRect(hwnd, &WndRect);
			if (pThis->m_bIsImageMode) {
				SetWindowPos(pThis->m_hWnd, hwnd, WndRect.left - pThis->m_nSize, WndRect.top - pThis->m_nSize, 0, 0, SWP_NOSIZE | SWP_NOACTIVATE);
			}
			else {
				SetWindowPos(pThis->m_hWnd, hwnd, WndRect.left + pThis->m_nxOffset - pThis->m_nSize, WndRect.top + pThis->m_nyOffset - pThis->m_nSize, 0, 0, SWP_NOSIZE | SWP_NOACTIVATE);
			}

			if (pWndPos->flags & SWP_SHOWWINDOW) {
				if (pThis->m_Status & SS_ENABLED && !(pThis->m_Status & SS_PARENTVISIBLE))
				{
					pThis->m_bUpdate = true;
					::ShowWindow(pThis->m_hWnd, SW_SHOWNOACTIVATE);
					pThis->m_Status |= SS_VISABLE | SS_PARENTVISIBLE;
				}
			}
			else if (pWndPos->flags & SWP_HIDEWINDOW) {
				if (pThis->m_Status & SS_ENABLED)
				{
					::ShowWindow(pThis->m_hWnd, SW_HIDE);
					pThis->m_Status &= ~(SS_VISABLE | SS_PARENTVISIBLE);
				}
			}
			break;
		}
		
	case WM_MOVE:
		if(pThis->m_Status & SS_VISABLE) {
			RECT WndRect;
			GetWindowRect(hwnd, &WndRect);
			if (pThis->m_bIsImageMode) {
				SetWindowPos(pThis->m_hWnd, hwnd, WndRect.left - pThis->m_nSize, WndRect.top - pThis->m_nSize, 0, 0, SWP_NOSIZE | SWP_NOACTIVATE);
			}
			else {
				SetWindowPos(pThis->m_hWnd, hwnd, WndRect.left + pThis->m_nxOffset - pThis->m_nSize, WndRect.top + pThis->m_nyOffset - pThis->m_nSize, 0, 0, SWP_NOSIZE | SWP_NOACTIVATE);
			}
		}
		break;

	case WM_SIZE:
		if(pThis->m_Status & SS_ENABLED) {
			if(SIZE_MAXIMIZED == wParam || SIZE_MINIMIZED == wParam) {
				::ShowWindow(pThis->m_hWnd, SW_HIDE);
				pThis->m_Status &= ~SS_VISABLE;
			}
			// Parent maybe resized even if invisible
			else if(pThis->m_Status & SS_PARENTVISIBLE) {
				// Awful! It seems that if the window size was not decreased
				// the window region would never be updated until WM_PAINT was sent.
				// So do not Update() until next WM_PAINT is received in this case
				if(LOWORD(lParam) > LOWORD(pThis->m_WndSize) || HIWORD(lParam) > HIWORD(pThis->m_WndSize))
					pThis->m_bUpdate = true;
				else
					pThis->Update(hwnd);

				if(!(pThis->m_Status & SS_VISABLE)) {
					::ShowWindow(pThis->m_hWnd, SW_SHOWNOACTIVATE);
					pThis->m_Status |= SS_VISABLE;
				}
			}
			pThis->m_WndSize = lParam;
		}
		break;

	case WM_PAINT:
		{
			if(pThis->m_bUpdate) {
				pThis->Update(hwnd);
				pThis->m_bUpdate = false;
			}
			break;
		}

		// In some cases of sizing, the up-right corner of the parent window region would not be properly updated
		// Update() again when sizing is finished
	case WM_EXITSIZEMOVE:
		if(pThis->m_Status & SS_VISABLE) {
			pThis->Update(hwnd);
		}
		break;

	case WM_SHOWWINDOW:
		if(pThis->m_Status & SS_ENABLED) {
			// the window is being hidden
			if(!wParam) {
				::ShowWindow(pThis->m_hWnd, SW_HIDE);
				pThis->m_Status &= ~(SS_VISABLE | SS_PARENTVISIBLE);
			}
			else if(!(pThis->m_Status & SS_PARENTVISIBLE)) {
				//pThis->Update(hwnd);
				pThis->m_bUpdate = true;
				::ShowWindow(pThis->m_hWnd, SW_SHOWNOACTIVATE);
				pThis->m_Status |= SS_VISABLE | SS_PARENTVISIBLE;
			}
		}
		break;

	case WM_DESTROY:
		DestroyWindow(pThis->m_hWnd);	// Destroy the shadow
		break;
	case WM_NCDESTROY:
		GetShadowMap().erase(hwnd);	// Remove this window and shadow from the map
		break;
	}

	return CallWindowProc((WNDPROC)pThis->m_OriParentProc, hwnd, uMsg, wParam, lParam);
}

//Formats GetLastError() value.
void GetLastErrorMessage() 
{          
	LPVOID lpMsgBuf;
	FormatMessage(
		FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
		NULL, GetLastError(),
		MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
		(LPTSTR)&lpMsgBuf, 0, NULL
	);

	// Display the string.
	//MessageBox(NULL, (const wchar_t*)lpMsgBuf, L"GetLastError", MB_OK | MB_ICONINFORMATION);

	// Free the buffer.
	LocalFree(lpMsgBuf);
}

void CShadowUI::Update(HWND hParent)
{
	if(!m_bIsShowShadow || !(m_Status & SS_VISABLE)) return;
	RECT WndRect;
	GetWindowRect(hParent, &WndRect);
	int nShadWndWid;
	int nShadWndHei;
	if (m_bIsImageMode) {
		if(m_sShadowImage.IsEmpty()) return;
		nShadWndWid = WndRect.right - WndRect.left + m_nSize * 2;
		nShadWndHei = WndRect.bottom - WndRect.top + m_nSize * 2;
	}
	else {
		if (m_nSize == 0) return;
		nShadWndWid = WndRect.right - WndRect.left + m_nSize * 2;
		nShadWndHei = WndRect.bottom - WndRect.top + m_nSize * 2;
	}
		
	// Create the alpha blending bitmap
	BITMAPINFO bmi;        // bitmap header
	ZeroMemory(&bmi, sizeof(BITMAPINFO));
	bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
	bmi.bmiHeader.biWidth = nShadWndWid;
	bmi.bmiHeader.biHeight = nShadWndHei;
	bmi.bmiHeader.biPlanes = 1;
	bmi.bmiHeader.biBitCount = 32;         // four 8-bit components
	bmi.bmiHeader.biCompression = BI_RGB;
	bmi.bmiHeader.biSizeImage = nShadWndWid * nShadWndHei * 4;
	BYTE *pvBits;          // pointer to DIB section
	HBITMAP hbitmap = CreateDIBSection(NULL, &bmi, DIB_RGB_COLORS, (void **)&pvBits, NULL, 0);
	if (hbitmap == NULL) {
		GetLastErrorMessage();
	}

	HDC hMemDC = CreateCompatibleDC(NULL);
	if (hMemDC == NULL) {
		GetLastErrorMessage();
	}
	HBITMAP hOriBmp = (HBITMAP)SelectObject(hMemDC, hbitmap);
	if (GetLastError()!=0) {
		GetLastErrorMessage();
	}
	if (m_bIsImageMode) {
		RECT rcPaint = {0, 0, nShadWndWid, nShadWndHei};
		const TDrawInfo* pDrawInfo = m_pManager->GetDrawInfo(m_sShadowImage, _T(""));
		if(pDrawInfo != NULL) {
			const TImageInfo* data = m_pManager->GetImageEx(pDrawInfo->sImageName, pDrawInfo->sResType, pDrawInfo->dwMask, pDrawInfo->bHSL, pDrawInfo->bGdiplus);
			if( !data ) return;    
			RECT rcBmpPart = {0};
			rcBmpPart.right = data->nX;
			rcBmpPart.bottom = data->nY;
			RECT corner = m_rcShadowCorner;
			CRenderEngine::DrawImage(hMemDC, data->hBitmap, rcPaint, rcPaint, rcBmpPart, corner, data->bAlpha, 0xFF, true, false, false);
		}
	}
	else {
		ZeroMemory(pvBits, bmi.bmiHeader.biSizeImage);
		MakeShadow((UINT32 *)pvBits, hParent, &WndRect);
	}

	POINT ptDst;
	if (m_bIsImageMode) {
		ptDst.x = WndRect.left - m_nSize;
		ptDst.y = WndRect.top - m_nSize;
	}
	else {
		ptDst.x = WndRect.left + m_nxOffset - m_nSize;
		ptDst.y = WndRect.top + m_nyOffset - m_nSize;
	}

	POINT ptSrc = {0, 0};
	SIZE WndSize = {nShadWndWid, nShadWndHei};
	BLENDFUNCTION blendPixelFunction= { AC_SRC_OVER, 0, 255, AC_SRC_ALPHA };
	MoveWindow(m_hWnd, ptDst.x, ptDst.y, nShadWndWid, nShadWndHei, FALSE);
	BOOL bRet= ::UpdateLayeredWindow(m_hWnd, NULL, &ptDst, &WndSize, hMemDC, &ptSrc, 0, &blendPixelFunction, ULW_ALPHA);
	_ASSERT(bRet); // something was wrong....
	// Delete used resources
	SelectObject(hMemDC, hOriBmp);
	DeleteObject(hbitmap);
	DeleteDC(hMemDC);
}

// ---------------------------------------------------------------------------
// [2026-09-25] R25 - anti-aliased inner hole for the shadow.
//
// Symptom: on a layered anti-aliased rounded window the top corners showed a
// dark line, and the bottom corners showed a broken / too-thin shadow.
//
// Root cause: the hole punched into the shadow bitmap was cut with a 1-BIT
// silhouette (PtInRegion over hParentRgn), while the window content itself is
// cut with an 8x8 supersampled alpha mask (CPaintManagerUI::
// FillRoundRectAlphaMask). The two outlines disagree by up to 1px along the
// corner arc, and the shadow window is composited ABOVE the parent window, so:
//   * scan lines where the 1-bit arc sits INSIDE the real arc keep shadow on
//     pixels the window already covers fully -> they get darkened. On a
//     saturated title bar that reads as a black line on the top corners.
//   * scan lines where the 1-bit arc sits OUTSIDE the real arc zero out shadow
//     that belongs to the outside of the arc -> the corner shadow is bitten
//     off, which reads as broken / too thin shadow on the bottom corners.
//
// Fix: instead of the boolean hole, fade the shadow by the SAME coverage the
// window mask uses. cov = 8x8 supersampled area coverage of the rounded rect at
// that pixel (0..255), so:
//     cov == 255 (inside)   -> alpha 0                      (the hole, as before)
//     0 < cov < 255 (arc)   -> alpha * (255 - cov) / 255    (smooth + aligned)
//     cov == 0 (outside)    -> alpha unchanged
// Straight edges are unaffected: coverage there is always 255 or 0, never
// partial, so the top / bottom / left / right shadow bands keep their exact
// current values (verified: 180 / 205 / 231 on all four sides).
//
// NOTE: this file is compiled without a UTF-8 BOM - keep every comment ASCII.
// ---------------------------------------------------------------------------
// Exact port of CPaintManagerUI::FillRoundRectAlphaMask's coverage maths
// (same pixel-centre sampling, same corner centre, same 8x8 supersampling),
// otherwise the two outlines would keep drifting apart by half a pixel.
static int ShadowRoundRectCoverage(int x, int y, int w, int h, int r)
{
	if (r <= 0 || w <= 0 || h <= 0) return 255;
	if (r > w / 2) r = w / 2;
	if (r > h / 2) r = h / 2;
	if (r < 1) return 255;
	if (x < 0 || y < 0 || x >= w || y >= h) return 0;

	const double cx = w * 0.5;
	const double cy = h * 0.5;
	const double hw = cx;
	const double hh = cy;
	const double px = fabs(x + 0.5 - cx) - (hw - r);
	const double py = fabs(y + 0.5 - cy) - (hh - r);
	// Inside band / straight edge: the window boundary IS the mask boundary.
	if (px <= 0.0 || py <= 0.0) return 255;

	// Corner block: corner centre = the inner rect's corner point.
	// Getting the sign wrong moves the centre to the diagonally opposite side of
	// the window, every sample falls outside and the whole corner reads 0.
	const double ccx = cx + ((x + 0.5 < cx) ? -(hw - r) : (hw - r));
	const double ccy = cy + ((y + 0.5 < cy) ? -(hh - r) : (hh - r));
	const double rr = (double)r * r;
	int nIn = 0;
	for (int sy = 0; sy < 8; ++sy)
	{
		const double syp = y + (sy + 0.5) / 8.0;
		for (int sx = 0; sx < 8; ++sx)
		{
			const double sxp = x + (sx + 0.5) / 8.0;
			const double ddx = sxp - ccx;
			const double ddy = syp - ccy;
			if (ddx * ddx + ddy * ddy <= rr) ++nIn;
		}
	}
	return (nIn * 255 + 32) / 64;
}

// [2026-09-26 R31] One-key rollback for the corner colour compensation below.
// Default ON. Set the environment variable ZP_SHADOW_COLOR_COMP=0 (before start-up)
// to fall back to the plain linear alpha attenuation R28 introduced.
static bool ShadowCornerColorCompEnabled()
{
	static int s_nEnabled = -1;
	if (s_nEnabled < 0)
	{
		TCHAR szBuf[8] = { 0 };
		const DWORD dwRet = ::GetEnvironmentVariable(_T("ZP_SHADOW_COLOR_COMP"), szBuf, 8);
		s_nEnabled = (dwRet == 1 && szBuf[0] == _T('0')) ? 0 : 1;
	}
	return s_nEnabled != 0;
}

void CShadowUI::MakeShadow(UINT32 *pShadBits, HWND hParent, RECT *rcParent)
{
	// The shadow algorithm:
	// Get the region of parent window,
	// Apply morphologic erosion to shrink it into the size (ShadowWndSize - Sharpness)
	// Apply modified (with blur effect) morphologic dilation to make the blurred border
	// The algorithm is optimized by assuming parent window is just "one piece" and without "wholes" on it

	// Get the region of parent window.
	//
	// [2026-09-24] In layered anti-aliased rounded-corner mode the window deliberately has
	// NO window region: CPaintManagerUI::GetRoundCorner() returns {0,0} so that every
	// window's OnSize skips CreateRoundRectRgn/SetWindowRgn (a 1-bit HRGN would re-cut the
	// smooth anti-aliased corner produced by the alpha mask). Consequence: GetWindowRgn
	// below cannot read the real shape, hParentRgn keeps the plain full rectangle, so the
	// shadow's inner silhouette degrades into a right angle. In the four corners of a
	// rounded window the background then shows through inside a SQUARE shadow frame
	// (looks like a "white corner").
	// Fix: when no valid region is available, synthesise a rounded region from the window's
	// configured corner radius. radius == 0 keeps the old rectangle behaviour, and windows
	// that DO have a region (GetWindowRgn returns SIMPLEREGION/COMPLEXREGION) are untouched.
	const int nParentW = abs(rcParent->right - rcParent->left);
	const int nParentH = abs(rcParent->bottom - rcParent->top);
	// [2026-09-25] R25: radius used by the anti-aliased hole further down. Kept
	// separate from szRgnCorner because that one is only applied when the radius
	// fits inside the window; here we only need "is there a radius at all"
	// (0 == no rounded corner == plain rectangle hole, i.e. the old behaviour).
	SIZE szAaCorner = { 0, 0 };
	if (m_pManager != NULL) szAaCorner = m_pManager->GetRoundCornerForShadow();
	HRGN hParentRgn = CreateRectRgn(0, 0, nParentW, nParentH);
	const int nRgnType = ::GetWindowRgn(hParent, hParentRgn);
	if (nRgnType == ERROR || nRgnType == NULLREGION)
	{
		SIZE szRgnCorner = { 0, 0 };
		if (m_pManager != NULL) szRgnCorner = m_pManager->GetRoundCornerForShadow();
		if (szRgnCorner.cx > 0 && szRgnCorner.cy > 0
			&& szRgnCorner.cx * 2 < nParentW && szRgnCorner.cy * 2 < nParentH)
		{
			::DeleteObject(hParentRgn);
			// [2026-09-24] R17: CreateRoundRectRgn takes 2x radius.
			// CreateRoundRectRgn's nWidthEllipse/nHeightEllipse is the FULL width/height of
			// the corner ellipse (radius = value / 2), while GetRoundCornerForShadow() returns
			// the RADIUS (same unit as CPaintManagerUI::FillRoundRectAlphaMask, which uses the
			// value directly as a radius). Feeding the radius here produced a shadow silhouette
			// with only HALF the window's corner radius: the dark band cut across at a smaller
			// arc and left a sliver of unshadowed background glued to the real arc (a "white
			// edge" on light backgrounds, a stray shadow blob on dark ones).
			// [2026-09-25] R25: dropped the old "+1". CreateRoundRectRgn(0,0,W,H,..)
			// already covers pixel columns [0,W) and rows [0,H) - exactly the pixel grid
			// the scan loop samples with PtInRegion(j,i). The +1 pushed the right and
			// bottom arcs 1px further out than the window's own mask arc, which made the
			// bottom-right corner shadow heavier than the other three corners.
			hParentRgn = ::CreateRoundRectRgn(0, 0, nParentW, nParentH,
				szRgnCorner.cx * 2, szRgnCorner.cy * 2);
		}
	}

	// Determine the Start and end point of each horizontal scan line
	SIZE szParent = {rcParent->right - rcParent->left, rcParent->bottom - rcParent->top};
	SIZE szShadow = {szParent.cx + 2 * m_nSize, szParent.cy + 2 * m_nSize};
	// Extra 2 lines (set to be empty) in ptAnchors are used in dilation
	int nAnchors = max(szParent.cy, szShadow.cy);	// # of anchor points pares
	int (*ptAnchors)[2] = new int[nAnchors + 2][2];
	int (*ptAnchorsOri)[2] = new int[szParent.cy][2];	// anchor points, will not modify during erosion
	ptAnchors[0][0] = szParent.cx;
	ptAnchors[0][1] = 0;
	ptAnchors[nAnchors + 1][0] = szParent.cx;
	ptAnchors[nAnchors + 1][1] = 0;
	if(m_nSize > 0) {
		// Put the parent window anchors at the center
		for(int i = 0; i < m_nSize; i++) {
			ptAnchors[i + 1][0] = szParent.cx;
			ptAnchors[i + 1][1] = 0;
			ptAnchors[szShadow.cy - i][0] = szParent.cx;
			ptAnchors[szShadow.cy - i][1] = 0;
		}
		ptAnchors += m_nSize;
	}
	for(int i = 0; i < szParent.cy; i++) {
		// find start point
		int j;
		for(j = 0; j < szParent.cx; j++) {
			if(PtInRegion(hParentRgn, j, i)) {
				ptAnchors[i + 1][0] = j + m_nSize;
				ptAnchorsOri[i][0] = j;
				break;
			}
		}
		// Start point not found
		if(j >= szParent.cx) {
			ptAnchors[i + 1][0] = szParent.cx;
			ptAnchorsOri[i][1] = 0;
			ptAnchors[i + 1][0] = szParent.cx;
			ptAnchorsOri[i][1] = 0;
		}
		else {
			// find end point
			for(j = szParent.cx - 1; j >= ptAnchors[i + 1][0]; j--) {
				if(PtInRegion(hParentRgn, j, i)) {
					ptAnchors[i + 1][1] = j + 1 + m_nSize;
					ptAnchorsOri[i][1] = j + 1;
					break;
				}
			}
		}
	}

	if(m_nSize > 0)
		ptAnchors -= m_nSize;	// Restore pos of ptAnchors for erosion
	int (*ptAnchorsTmp)[2] = new int[nAnchors + 2][2];	// Store the result of erosion
	// First and last line should be empty
	ptAnchorsTmp[0][0] = szParent.cx;
	ptAnchorsTmp[0][1] = 0;
	ptAnchorsTmp[nAnchors + 1][0] = szParent.cx;
	ptAnchorsTmp[nAnchors + 1][1] = 0;
	int nEroTimes = 0;
	// morphologic erosion
	for(int i = 0; i < m_nSharpness - m_nSize; i++) {
		nEroTimes++;
		//ptAnchorsTmp[1][0] = szParent.cx;
		//ptAnchorsTmp[1][1] = 0;
		//ptAnchorsTmp[szParent.cy + 1][0] = szParent.cx;
		//ptAnchorsTmp[szParent.cy + 1][1] = 0;
		for(int j = 1; j < nAnchors + 1; j++) {
			ptAnchorsTmp[j][0] = max(ptAnchors[j - 1][0], max(ptAnchors[j][0], ptAnchors[j + 1][0])) + 1;
			ptAnchorsTmp[j][1] = min(ptAnchors[j - 1][1], min(ptAnchors[j][1], ptAnchors[j + 1][1])) - 1;
		}
		// Exchange ptAnchors and ptAnchorsTmp;
		int (*ptAnchorsXange)[2] = ptAnchorsTmp;
		ptAnchorsTmp = ptAnchors;
		ptAnchors = ptAnchorsXange;
	}

	// morphologic dilation
	ptAnchors += (m_nSize < 0 ? -m_nSize : 0) + 1;	// now coordinates in ptAnchors are same as in shadow window
	// Generate the kernel
	int nKernelSize = m_nSize > m_nSharpness ? m_nSize : m_nSharpness;
	int nCenterSize = m_nSize > m_nSharpness ? (m_nSize - m_nSharpness) : 0;
	UINT32 *pKernel = new UINT32[(2 * nKernelSize + 1) * (2 * nKernelSize + 1)];
	UINT32 *pKernelIter = pKernel;
	for(int i = 0; i <= 2 * nKernelSize; i++) {
		for(int j = 0; j <= 2 * nKernelSize; j++) {
			double dLength = sqrt((i - nKernelSize) * (i - nKernelSize) + (j - nKernelSize) * (double)(j - nKernelSize));
			if(dLength < nCenterSize)
				*pKernelIter = m_nDarkness << 24 | PreMultiply(m_Color, m_nDarkness);
			else if(dLength <= nKernelSize) {
				UINT32 nFactor = ((UINT32)((1 - (dLength - nCenterSize) / (m_nSharpness + 1)) * m_nDarkness));
				*pKernelIter = nFactor << 24 | PreMultiply(m_Color, nFactor);
			}
			else
				*pKernelIter = 0;
			//TRACE("%d ", *pKernelIter >> 24);
			pKernelIter ++;
		}
		//TRACE("\n");
	}
	// Generate blurred border
	for(int i = nKernelSize; i < szShadow.cy - nKernelSize; i++)
	{
		int j;
		if(ptAnchors[i][0] < ptAnchors[i][1])
		{
			// Start of line
			for(j = ptAnchors[i][0]; j < min(max(ptAnchors[i - 1][0], ptAnchors[i + 1][0]) + 1, ptAnchors[i][1]); j++)
			{
				for(int k = 0; k <= 2 * nKernelSize; k++)
				{
					UINT32 *pPixel = pShadBits +
						(szShadow.cy - i - 1 + nKernelSize - k) * szShadow.cx + j - nKernelSize;
					UINT32 *pKernelPixel = pKernel + k * (2 * nKernelSize + 1);
					for(int l = 0; l <= 2 * nKernelSize; l++)
					{
						if(*pPixel < *pKernelPixel)
							*pPixel = *pKernelPixel;
						pPixel++;
						pKernelPixel++;
					}
				}
			}	// for() start of line

			// End of line
			for(j = max(j, min(ptAnchors[i - 1][1], ptAnchors[i + 1][1]) - 1); j < ptAnchors[i][1]; j++)
			{
				for(int k = 0; k <= 2 * nKernelSize; k++)
				{
					UINT32 *pPixel = pShadBits +
						(szShadow.cy - i - 1 + nKernelSize - k) * szShadow.cx + j - nKernelSize;
					UINT32 *pKernelPixel = pKernel + k * (2 * nKernelSize + 1);
					for(int l = 0; l <= 2 * nKernelSize; l++)
					{
						if(*pPixel < *pKernelPixel)
							*pPixel = *pKernelPixel;
						pPixel++;
						pKernelPixel++;
					}
				}
			}	// for() end of line

		}
	}	// for() Generate blurred border

	// Erase unwanted parts and complement missing
	UINT32 clCenter = m_nDarkness << 24 | PreMultiply(m_Color, m_nDarkness);
	const int nAaRadius = (szAaCorner.cx > 0) ? szAaCorner.cx : 0;
	for(int i = min(nKernelSize, max(m_nSize - m_nyOffset, 0)); i < max(szShadow.cy - nKernelSize, min(szParent.cy + m_nSize - m_nyOffset, szParent.cy + 2 * m_nSize)); i++) {
		UINT32 *pLine = pShadBits + (szShadow.cy - i - 1) * szShadow.cx;
		// Line is not covered by parent window 
		if(i - m_nSize + m_nyOffset < 0 || i - m_nSize + m_nyOffset >= szParent.cy)	{
			for(int j = ptAnchors[i][0]; j < ptAnchors[i][1]; j++) {
				*(pLine + j) = clCenter;
			}
		}
		else {
			for(int j = ptAnchors[i][0]; j < min(ptAnchorsOri[i - m_nSize + m_nyOffset][0] + m_nSize - m_nxOffset, ptAnchors[i][1]); j++)
				*(pLine + j) = clCenter;
			for(int j = max(ptAnchorsOri[i - m_nSize + m_nyOffset][1] + m_nSize - m_nxOffset, ptAnchors[i][0]); j < ptAnchors[i][1]; j++)
				*(pLine + j) = clCenter;
			// [2026-09-25] R25: the anti-aliased hole replaces the old 1-bit
			// "*(pLine + j) = 0" loop. It must stay AFTER the two clCenter fill
			// passes above, otherwise those passes would overwrite the fade.
			// Scope is the whole parent-rect span of this line (not just the
			// ptAnchorsOri span), so the partially covered pixels that the 1-bit
			// silhouette classified as "outside" are faded too.
			{
				const int nHoleX0 = max(m_nSize - m_nxOffset, 0);
				const int nHoleX1 = min(szParent.cx + m_nSize - m_nxOffset, szShadow.cx);
				const int nHoleY = i - m_nSize + m_nyOffset;
				for(int j = nHoleX0; j < nHoleX1; j++)
				{
					UINT32 nPixel = *(pLine + j);
					if(nPixel == 0) continue;
					const int nCov = ShadowRoundRectCoverage(j - (m_nSize - m_nxOffset), nHoleY,
						szParent.cx, szParent.cy, nAaRadius);
					if(nCov >= 255) { *(pLine + j) = 0; continue; }
					if(nCov <= 0) continue;
					UINT32 nAlpha = ((nPixel >> 24) * (255 - nCov)) / 255;
					*(pLine + j) = (nAlpha == 0) ? 0
						: ((nAlpha << 24) | PreMultiply(m_Color, (unsigned char)nAlpha));
				}
			}
		}
	}

	// -----------------------------------------------------------------------
	// [2026-09-26] R26 - corner shadow top-up.
	//
	// The morphological dilation above grows the silhouette by
	// (m_nSharpness - m_nSize) erosion steps and then dilates with a radius of
	// max(m_nSize, m_nSharpness). Along a straight edge that lands exactly
	// m_nSize px outside the window - which is why the four straight bands carry
	// the expected 75 / 50 / 25 alpha. Around a CONVEX corner it does not: every
	// erosion step takes max() over the three neighbouring rows, so on the corner
	// arc it tightens faster than the arc itself, and the band left after the
	// dilation is 1..3 px too narrow there. On a white background that reads as
	// "the shadow is missing at the bottom corners".
	//
	// Fix: after the erase pass, top up every pixel that is FULLY outside the
	// window (coverage == 0) using the analytic distance to the rounded rect and
	// the very same radial profile the kernel uses. Straight edges are untouched
	// - they already carry the profile value and the update is a max(). Pixels the
	// window covers even partially are skipped, so the hole stays a hole.
	// Note the ordering: this must run AFTER the erase/hole pass above, otherwise
	// the erase would wipe the corner band again.
	// -----------------------------------------------------------------------
	if (nAaRadius > 0)
	{
		const int nEroSteps = (m_nSharpness > m_nSize) ? (int)(m_nSharpness - m_nSize) : 0;
		// [2026-09-26 R31] Parent window content x mask, premultiplied (the value the
		// compensation below needs). Only the layered rounded-mask path has it; every other
		// path, and any frame painted before the parent has painted at all, leaves it NULL
		// and the block below falls back to the old pure-black band.
		const bool bColorComp = ShadowCornerColorCompEnabled();
		COLORREF* pBkgBits = NULL;
		RECT rcBkg = { 0, 0, 0, 0 };
		int nBkgW = 0;
		int nBkgH = 0;
		if (bColorComp && m_pManager != NULL)
			pBkgBits = m_pManager->GetLayeredContentBits(&nBkgW, &nBkgH, &rcBkg);
		const double dCx = szParent.cx * 0.5;
		const double dCy = szParent.cy * 0.5;
		const double dHw = dCx;
		const double dHh = dCy;
		const int nPad = nKernelSize + 2;
		for (int iy = -nPad; iy <= szParent.cy + nPad; ++iy)
		{
			const int i = iy + m_nSize - m_nyOffset;
			if (i < 0 || i >= szShadow.cy) continue;
			UINT32 *pLineTop = pShadBits + (szShadow.cy - i - 1) * szShadow.cx;
			const double dPy = fabs(iy + 0.5 - dCy) - (dHh - nAaRadius);
			for (int jx = -nPad; jx <= szParent.cx + nPad; ++jx)
			{
				const int j = jx + m_nSize - m_nxOffset;
				if (j < 0 || j >= szShadow.cx) continue;
				// Straight-band interior (the bulk of the window): nothing to do.
				const double dPx = fabs(jx + 0.5 - dCx) - (dHw - nAaRadius);
				if (dPx <= 0.0 && dPy <= 0.0) continue;
				// [2026-09-26 R28] Coverage of the window's own anti-aliased mask at
				// this pixel. The old guard was 'coverage != 0 - skip', which is why
				// the corner arc still looked wrong. Along a straight edge coverage is
				// only ever 0 or 255, but the corner arc carries a one pixel ring where
				// coverage is strictly between the two. Those pixels were skipped here,
				// kept whatever the too tight morphological band had produced, and
				// showed up as a bright dash hugging the arc: a pale seam between the
				// title bar and the shadow on the top corners, a stair stepped dashed
				// edge on the bottom ones. The bottom corners had twice as many such
				// pixels and twice the gap, which is why the two ends of the window
				// looked like two different defects. Now only a FULLY covered pixel is
				// skipped, so the hole R25 punched stays a hole; partially covered
				// pixels are topped up and attenuated further down by the fraction of
				// the pixel the window does not cover.
				const int nCov = ShadowRoundRectCoverage(jx, iy, szParent.cx, szParent.cy, nAaRadius);
				if (nCov >= 255) continue;               // fully covered: the hole stays a hole
				double d;
				// [2026-09-25 R27] Calibrate the corner band so it joins the four
				// straight edges seamlessly:
				//  * the two straight-edge branches below used to return the distance
				//    to the straight-band inner boundary instead of to the window
				//    edge, i.e. nAaRadius too small a deduction. d stayed above
				//    nKernelSize so the top-up never fired along the four edges;
				//    those pixels kept the base band while the corner arc got the
				//    full analytic value -- the arc sat +12 alpha above the band at
				//    every distance and reached b=3.0 instead of 2.5, so every corner
				//    showed a hard seam plus a fatter, darker hook.
				//  * with all three branches corrected d is simply the rounded-rect
				//    signed distance field, so this top-up becomes a pure function of
				//    the distance and the whole band matches the four edges exactly.
				//  * u carries +0.5 because the base band is calibrated as
				//    K of d plus 2.5: 1/2/3 px outside -> alpha 75/50/25. Without
				//    it the arc peaked at 87 instead of 75.
				if (dPx <= 0.0) d = dPy - nAaRadius;                    // nearest horizontal edge
				else if (dPy <= 0.0) d = dPx - nAaRadius;               // nearest vertical edge
				else d = sqrt(dPx * dPx + dPy * dPy) - nAaRadius;   // nearest corner arc
				// [2026-09-26 R29] A partially covered pixel whose centre is still inside
				// the window, d <= 0, used to be skipped by the guard that stood here, and
				// that guard is what left a pale seam between the shadow and the window all
				// along the corner arcs -- most visible on the top left and top right
				// rounding of the main window and of the dialogs.
				//
				// Such a pixel is only partly covered by the window, but the part that is
				// NOT covered lies outside the window, between 0 and one pixel away from
				// the silhouette. That is exactly the rim the band profile is calibrated
				// for, so the band value here is the one at distance 0. Clamping to 0 keeps
				// the corner arc a pure function of the distance, the same shape R27 gave
				// to the fully outside pixels of the arc. The pixel is then combined below
				// by coverage -- R28 attenuated its alpha linearly, R31 instead keeps the
				// band alpha and replaces the black source with the coverage-corrected
				// content colour.
				//
				// Scope: only 0 < coverage < 255 can reach this line. A fully covered pixel
				// was skipped above so the hole stays a hole, and a fully outside one has
				// d > 0, so clamping is a no-op there. The four straight edges, the whole
				// outer arc and the hole are therefore left bit for bit untouched.
				if (d < 0.0) d = 0.0;                       // clamp to the window rim
				const double u = d + nEroSteps + 0.5;
				UINT32 nWant;
				if (u < (double)nCenterSize) nWant = m_nDarkness;
				else if (u <= (double)nKernelSize)
					nWant = (UINT32)((1.0 - (u - nCenterSize) / (double)(m_nSharpness + 1)) * m_nDarkness);
				else continue;
				if (nWant == 0) continue;
				// [2026-09-26 R28 -> R31] SUPERSEDED. This used to be a plain linear
				// attenuation, as = a * (255 - cov) / 255 with a black source. It is the
				// correct lower bound only when the content colour equals the desktop
				// colour, and it is still the fallback used below when the parent content
				// bitmap is unavailable, but on darker content it under-attenuated and left
				// the pale 1px arc along the top corners. R31 replaced it with the exact
				// coverage-corrected source colour.
				// [2026-09-26 R31] Exact colour compensation for the partially covered rim.
				//
				// What the window + shadow stack really does at a pixel the window only partly
				// covers (coverage c, content colour w, desktop D):
				//     under = w*c + D*(1-c)          window composited onto the desktop
				//     out   = under*(1-as) + S       shadow window composited on top of it
				// and what it SHOULD look like is the shadow darkening only the part of the pixel
				// the window does not cover:
				//     ideal = w*c + D*(1-c)*(1-a)
				// Solving out == ideal with as = a (the band value, undiminished) gives
				//     S = a*w*c
				// which is independent of D -- so the ring no longer depends on what sits behind
				// the window. The rule that used to stand here was as = a*(1-c) with S = 0, i.e. a
				// plain black shadow thinned by the coverage; that is the correct lower bound only
				// when w == D. For darker content (the green title bar, w ~ 96..131 on a bright
				// desktop) it under-attenuates by
				//     delta = a * (1-c) * (D-w) * c / 255
				// which is 10..14 of 255 on the top corners of this app: the pale 1px arc between
				// the shadow and the rounded window that R26..R30 could only shrink, never remove.
				//
				// w*c is exactly the premultiplied content pixel CPaintManagerUI keeps in
				// m_pBackgroundBits for the layered rounded-mask path, so the whole fix is "read
				// that pixel, multiply it by the band alpha, and do not dim the alpha". Straight
				// edges and the outer arc have c == 0, hence S == 0, hence keep the old black band
				// bit for bit. A fully covered pixel (c == 255) is the hole and never gets here.
				UINT32 nRgb = PreMultiply(m_Color, (unsigned char)nWant);
				if (nCov > 0 && pBkgBits != NULL)
				{
					const LONG nBx = jx - rcBkg.left;
					const LONG nBy = iy - rcBkg.top;
					if (nBx >= 0 && nBx < nBkgW && nBy >= 0 && nBy < nBkgH)
					{
						// bottom-up DIB: window row nBy lives at memory row (nBkgH - 1 - nBy)
						const UINT32 nPc = ((UINT32)pBkgBits[(LONG)(nBkgH - 1 - nBy) * nBkgW + nBx]) & 0x00FFFFFFu;
						if (nPc != 0)
						{
							const UINT32 nRc = (((nPc >> 16) & 0xFFu) * nWant + 127) / 255;
							const UINT32 nGc = (((nPc >> 8) & 0xFFu) * nWant + 127) / 255;
							const UINT32 nBc = ((nPc & 0xFFu) * nWant + 127) / 255;
							nRgb = (nRc << 16) | (nGc << 8) | nBc;
						}
					}
				}
				if (nWant == 0) continue;
				if ((*(pLineTop + j) >> 24) < nWant)
					*(pLineTop + j) = (nWant << 24) | nRgb;
			}
		}
	}

	// Delete used resources
	delete[] (ptAnchors - (m_nSize < 0 ? -m_nSize : 0) - 1);
	delete[] ptAnchorsTmp;
	delete[] ptAnchorsOri;
	delete[] pKernel;
	DeleteObject(hParentRgn);
}

void CShadowUI::ShowShadow(bool bShow)
{
	m_bIsShowShadow = bShow;
}

bool CShadowUI::IsShowShadow() const
{
	return m_bIsShowShadow;
}


void CShadowUI::DisableShadow(bool bDisable)
{
	m_bIsDisableShadow = bDisable;
	if (m_hWnd != NULL) {
		if (m_bIsDisableShadow) {
			::ShowWindow(m_hWnd, SW_HIDE);
		}
		else {
			// Determine the initial show state of shadow according to parent window's state
			LONG lParentStyle = GetWindowLongPtr(GetParent(m_hWnd), GWL_STYLE);

			if (!(WS_VISIBLE & lParentStyle))	// Parent invisible
				m_Status = SS_ENABLED;
			else if ((WS_MAXIMIZE | WS_MINIMIZE) & lParentStyle)	// Parent visible but does not need shadow
				m_Status = SS_ENABLED | SS_PARENTVISIBLE;
			else {
				m_Status = SS_ENABLED | SS_VISABLE | SS_PARENTVISIBLE;
			}

			if ((WS_VISIBLE & lParentStyle) && !((WS_MAXIMIZE | WS_MINIMIZE) & lParentStyle)) {
				::ShowWindow(m_hWnd, SW_SHOWNOACTIVATE);
				Update(GetParent(m_hWnd));
			}
		}
	}
}

////TODO shadow disnable fix////
bool CShadowUI::IsDisableShadow() const 
{
	return m_bIsDisableShadow;
}

bool CShadowUI::SetSize(int NewSize)
{
	if(NewSize > 35 || NewSize < -35)
		return false;

	m_nSize = (signed char)NewSize;
	if(m_hWnd != NULL && (SS_VISABLE & m_Status))
		Update(GetParent(m_hWnd));
	return true;
}

bool CShadowUI::SetSharpness(unsigned int NewSharpness)
{
	if(NewSharpness > 35)
		return false;

	m_nSharpness = (unsigned char)NewSharpness;
	if(m_hWnd != NULL && (SS_VISABLE & m_Status))
		Update(GetParent(m_hWnd));
	return true;
}

bool CShadowUI::SetDarkness(unsigned int NewDarkness)
{
	if(NewDarkness > 255)
		return false;

	m_nDarkness = (unsigned char)NewDarkness;
	if(m_hWnd != NULL && (SS_VISABLE & m_Status))
		Update(GetParent(m_hWnd));
	return true;
}

bool CShadowUI::SetPosition(int NewXOffset, int NewYOffset)
{
	if(NewXOffset > 35 || NewXOffset < -35 ||
		NewYOffset > 35 || NewYOffset < -35)
		return false;
	
	m_nxOffset = (signed char)NewXOffset;
	m_nyOffset = (signed char)NewYOffset;
	if(m_hWnd != NULL && (SS_VISABLE & m_Status))
		Update(GetParent(m_hWnd));

	return true;
}

bool CShadowUI::SetColor(COLORREF NewColor)
{
	m_Color = NewColor;
	if(m_hWnd != NULL && (SS_VISABLE & m_Status))
		Update(GetParent(m_hWnd));

	return true;
}

bool CShadowUI::SetImage(LPCTSTR szImage)
{
	if (szImage == NULL)
		return false;

	m_bIsImageMode = true;
	m_sShadowImage = szImage;
	if(m_hWnd != NULL && (SS_VISABLE & m_Status))
		Update(GetParent(m_hWnd));

	return true;
}

bool CShadowUI::SetShadowCorner(RECT rcCorner)
{
	if (rcCorner.left < 0 || rcCorner.top < 0 || rcCorner.right < 0 || rcCorner.bottom < 0) return false;

	m_rcShadowCorner = rcCorner;
	if(m_hWnd != NULL && (SS_VISABLE & m_Status)) {
		Update(GetParent(m_hWnd));
	}

	return true;
}

bool CShadowUI::CopyShadow(CShadowUI* pShadow)
{
	if (m_bIsImageMode) {
		pShadow->SetImage(m_sShadowImage);
		pShadow->SetShadowCorner(m_rcShadowCorner);
		pShadow->SetSize((int)m_nSize);
	}
	else {
		pShadow->SetSize((int)m_nSize);
		pShadow->SetSharpness((unsigned int)m_nSharpness);
		pShadow->SetDarkness((unsigned int)m_nDarkness);
		pShadow->SetColor(m_Color);
		pShadow->SetPosition((int)m_nxOffset, (int)m_nyOffset);
	}

	pShadow->ShowShadow(m_bIsShowShadow);
	return true;
}
} //namespace DuiLib