/*

 * Copyright (C) 2007 Apple Inc.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1.  Redistributions of source code must retain the above copyright

 *     notice, this list of conditions and the following disclaimer. 

 * 2.  Redistributions in binary form must reproduce the above copyright

 *     notice, this list of conditions and the following disclaimer in the

 *     documentation and/or other materials provided with the distribution. 

 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of

 *     its contributors may be used to endorse or promote products derived

 *     from this software without specific prior written permission. 

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY

 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include "config.h"

#include "WebNodeHighlight.h"

#include "WebView.h"

#pragma warning(push, 0)

#include <WebCore/BitmapInfo.h>

#include <WebCore/Color.h>

#include <WebCore/GraphicsContext.h>

#include <WebCore/InspectorController.h>

#include <WebCore/Page.h>

#include <WebCore/WindowMessageBroadcaster.h>

#pragma warning(pop)

#include <wtf/OwnPtr.h>

#include <wtf/HashSet.h>

using namespace WebCore;

static LPCTSTR kOverlayWindowClassName = TEXT("WebNodeHighlightWindowClass");

static ATOM registerOverlayClass();

static LPCTSTR kWebNodeHighlightPointerProp = TEXT("WebNodeHighlightPointer");

WebNodeHighlight::WebNodeHighlight(WebView* webView)

    : m_inspectedWebView(webView)

    , m_overlay(0)

    , m_observedWindow(0)

    , m_showsWhileWebViewIsVisible(false)

{

    m_inspectedWebView->viewWindow(reinterpret_cast<OLE_HANDLE*>(&m_inspectedWebViewWindow));

}

WebNodeHighlight::~WebNodeHighlight()

{

    if (m_observedWindow)

        WindowMessageBroadcaster::removeListener(m_observedWindow, this);

    if (m_inspectedWebViewWindow)

        WindowMessageBroadcaster::removeListener(m_inspectedWebViewWindow, this);

    if (m_overlay)

        ::DestroyWindow(m_overlay);

}

void WebNodeHighlight::setShowsWhileWebViewIsVisible(bool shows)

{

    if (m_showsWhileWebViewIsVisible == shows)

        return;

    m_showsWhileWebViewIsVisible = shows;

    if (!m_showsWhileWebViewIsVisible) {

        hide();

        return;

    }

    bool webViewVisible = isWebViewVisible();

    if (isShowing() == webViewVisible)

        return;

    if (webViewVisible)

        show();

    else

        hide();

}

bool WebNodeHighlight::isWebViewVisible() const

{

    if (!m_inspectedWebViewWindow)

        return false;

    return IsWindowVisible(m_inspectedWebViewWindow);

}

void WebNodeHighlight::show()

{

    if (!m_overlay) {

        registerOverlayClass();

        m_overlay = ::CreateWindowEx(WS_EX_LAYERED | WS_EX_TOOLWINDOW | WS_EX_TRANSPARENT, kOverlayWindowClassName, 0, WS_POPUP,

                                     0, 0, 0, 0,

                                     m_inspectedWebViewWindow, 0, 0, 0);

        if (!m_overlay)

            return;

        ::SetProp(m_overlay, kWebNodeHighlightPointerProp, reinterpret_cast<HANDLE>(this));

        m_observedWindow = GetAncestor(m_inspectedWebViewWindow, GA_ROOT);

        WindowMessageBroadcaster::addListener(m_observedWindow, this);

        WindowMessageBroadcaster::addListener(m_inspectedWebViewWindow, this);

    }

    ASSERT(m_showsWhileWebViewIsVisible);

    update();

    SetWindowPos(m_overlay, 0, 0, 0, 0, 0, SWP_SHOWWINDOW | SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER | SWP_NOACTIVATE);

}

void WebNodeHighlight::hide()

{

    if (m_overlay)

        ::ShowWindow(m_overlay, SW_HIDE);

}

bool WebNodeHighlight::isShowing() const

{

    return m_overlay && ::IsWindowVisible(m_overlay);

}

void WebNodeHighlight::update()

{

    ASSERT(m_overlay);

    HDC hdc = ::CreateCompatibleDC(::GetDC(m_overlay));

    if (!hdc)

        return;

    RECT webViewRect;

    ::GetWindowRect(m_inspectedWebViewWindow, &webViewRect);

    SIZE size;

    size.cx = webViewRect.right - webViewRect.left;

    size.cy = webViewRect.bottom - webViewRect.top;

    BitmapInfo bitmapInfo = BitmapInfo::createBottomUp(IntSize(size));

    void* pixels = 0;

    OwnPtr<HBITMAP> hbmp(::CreateDIBSection(hdc, &bitmapInfo, DIB_RGB_COLORS, &pixels, 0, 0));

    ::SelectObject(hdc, hbmp.get());

    GraphicsContext context(hdc);

    m_inspectedWebView->page()->inspectorController()->drawNodeHighlight(context);

    BLENDFUNCTION bf;

    bf.BlendOp = AC_SRC_OVER;

    bf.BlendFlags = 0;

    bf.SourceConstantAlpha = 255;

    bf.AlphaFormat = AC_SRC_ALPHA;

    POINT srcPoint;

    srcPoint.x = 0;

    srcPoint.y = 0;

    POINT dstPoint;

    dstPoint.x = webViewRect.left;

    dstPoint.y = webViewRect.top;

    ::UpdateLayeredWindow(m_overlay, ::GetDC(0), &dstPoint, &size, hdc, &srcPoint, 0, &bf, ULW_ALPHA);

    ::DeleteDC(hdc);

}

void WebNodeHighlight::placeBehindWindow(HWND window)

{

    ASSERT(m_overlay);

    SetWindowPos(m_overlay, window, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE | SWP_NOACTIVATE);

}

static ATOM registerOverlayClass()

{

    static bool haveRegisteredWindowClass = false;

    if (haveRegisteredWindowClass)

        return true;

    WNDCLASSEX wcex;

    wcex.cbSize = sizeof(WNDCLASSEX);

    wcex.style          = 0;

    wcex.lpfnWndProc    = OverlayWndProc;

    wcex.cbClsExtra     = 0;

    wcex.cbWndExtra     = 0;

    wcex.hInstance      = 0;

    wcex.hIcon          = 0;

    wcex.hCursor        = LoadCursor(0, IDC_ARROW);

    wcex.hbrBackground  = 0;

    wcex.lpszMenuName   = 0;

    wcex.lpszClassName  = kOverlayWindowClassName;

    wcex.hIconSm        = 0;

    haveRegisteredWindowClass = true;

    return ::RegisterClassEx(&wcex);

}

LRESULT CALLBACK OverlayWndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)

{

    WebNodeHighlight* highlight = reinterpret_cast<WebNodeHighlight*>(::GetProp(hwnd, kWebNodeHighlightPointerProp));

    if (!highlight)

        return ::DefWindowProc(hwnd, msg, wParam, lParam);

    return ::DefWindowProc(hwnd, msg, wParam, lParam);

}

void WebNodeHighlight::onWebViewShowWindow(bool showing)

{

    if (!m_showsWhileWebViewIsVisible)

        return;

    if (isShowing() == showing)

        return;

    if (showing)

        show();

    else

        hide();

}

void WebNodeHighlight::onWebViewWindowPosChanged(WINDOWPOS* windowPos)

{

    bool sizing = !(windowPos->flags & SWP_NOSIZE);

    if (!sizing)

        return;

    if (!isShowing())

        return;

    update();

}

void WebNodeHighlight::onRootWindowPosChanged(WINDOWPOS* windowPos)

{

    bool moving = !(windowPos->flags & SWP_NOMOVE);

    bool sizing = !(windowPos->flags & SWP_NOSIZE);

    if (!moving)

        return;

    // Size changes are handled by onWebViewWindowPosChanged.

    if (sizing)

        return;

    if (!isShowing())

        return;

    update();

}

void WebNodeHighlight::windowReceivedMessage(HWND window, UINT msg, WPARAM wParam, LPARAM lParam)

{

    if (window == m_inspectedWebViewWindow) {

        switch (msg) {

            case WM_SHOWWINDOW:

                onWebViewShowWindow(wParam);

                break;

            case WM_WINDOWPOSCHANGED:

                onWebViewWindowPosChanged(reinterpret_cast<WINDOWPOS*>(lParam));

                break;

            default:

                break;

        }

        return;

    }

    ASSERT(window == m_observedWindow);

    switch (msg) {

        case WM_WINDOWPOSCHANGED:

            onRootWindowPosChanged(reinterpret_cast<WINDOWPOS*>(lParam));

            break;

        default:

            break;

    }

}