/*
 * This file is part of the WebKit project.
 *
 * Copyright (C) 2006 Apple Computer, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 */

#include "config.h"
#include "RenderThemeWin.h"

#include "CSSValueKeywords.h"
#include "Document.h"
#include "GraphicsContext.h"
#include "PlatformString.h"
#include "SoftLinking.h"

#include <cairo-win32.h>

/* 
 * The following constants are used to determine how a widget is drawn using
 * Windows' Theme API. For more information on theme parts and states see
 * http://msdn2.microsoft.com/en-us/library/bb773210(VS.85).aspx
 */
#define THEME_COLOR 204
#define THEME_FONT  210

// Generic state constants
#define TS_NORMAL    1
#define TS_HOVER     2
#define TS_ACTIVE    3
#define TS_DISABLED  4
#define TS_FOCUSED   5

// Button constants
#define BP_BUTTON    1
#define BP_RADIO     2
#define BP_CHECKBOX  3

// Textfield constants
#define TFP_TEXTFIELD 1
#define TFS_READONLY  6

// Combobox constants
#define CP_DROPDOWNBUTTON 1

SOFT_LINK_LIBRARY(uxtheme)
SOFT_LINK(uxtheme, OpenThemeData, HANDLE, WINAPI, (HWND hwnd, LPCWSTR pszClassList), (hwnd, pszClassList))
SOFT_LINK(uxtheme, CloseThemeData, HRESULT, WINAPI, (HANDLE hTheme), (hTheme))
SOFT_LINK(uxtheme, DrawThemeBackground, HRESULT, WINAPI, (HANDLE hTheme, HDC hdc, int iPartId, int iStateId, const RECT* pRect, const RECT* pClipRect), (hTheme, hdc, iPartId, iStateId, pRect, pClipRect))
SOFT_LINK(uxtheme, DrawThemeEdge, HRESULT, WINAPI, (HANDLE hTheme, HDC hdc, int iPartId, int iStateId, const RECT* pRect, unsigned uEdge, unsigned uFlags, const RECT* pClipRect), (hTheme, hdc, iPartId, iStateId, pRect, uEdge, uFlags, pClipRect))
SOFT_LINK(uxtheme, GetThemeContentRect, HRESULT, WINAPI, (HANDLE hTheme, HDC hdc, int iPartId, int iStateId, const RECT* pRect, const RECT* pContentRect), (hTheme, hdc, iPartId, iStateId, pRect, pContentRect))
SOFT_LINK(uxtheme, GetThemePartSize, HRESULT, WINAPI, (HANDLE hTheme, HDC hdc, int iPartId, int iStateId, RECT* pRect, int ts, SIZE* psz), (hTheme, hdc, iPartId, iStateId, pRect, ts, psz))
SOFT_LINK(uxtheme, GetThemeSysFont, HRESULT, WINAPI, (HANDLE hTheme, int iFontId, OUT LOGFONT* pFont), (hTheme, iFontId, pFont))
SOFT_LINK(uxtheme, GetThemeColor, HRESULT, WINAPI, (HANDLE hTheme, HDC hdc, int iPartId, int iStateId, int iPropId, OUT COLORREF* pColor), (hTheme, hdc, iPartId, iStateId, iPropId, pColor))

namespace WebCore {

RenderTheme* theme()
{
    static RenderThemeWin winTheme;
    return &winTheme;
}

RenderThemeWin::RenderThemeWin()
    : m_buttonTheme(0)
    , m_textFieldTheme(0)
    , m_menuListTheme(0)
{
}

RenderThemeWin::~RenderThemeWin()
{
    if (!uxthemeLibrary())
        return;

    close();
}

void RenderThemeWin::close()
{
    // This method will need to be called when the OS theme changes to flush our cached themes.
    if (m_buttonTheme)
        CloseThemeData(m_buttonTheme);
    if (m_textFieldTheme)
        CloseThemeData(m_textFieldTheme);
    if (m_menuListTheme)
        CloseThemeData(m_menuListTheme);
    m_buttonTheme = m_textFieldTheme = m_menuListTheme = 0;
}

Color RenderThemeWin::platformActiveSelectionBackgroundColor() const
{
    COLORREF color = GetSysColor(COLOR_HIGHLIGHT);
    return Color(GetRValue(color), GetGValue(color), GetBValue(color), 255);
}

Color RenderThemeWin::platformInactiveSelectionBackgroundColor() const
{
    COLORREF color = GetSysColor(COLOR_GRAYTEXT);
    return Color(GetRValue(color), GetGValue(color), GetBValue(color), 255);
}

Color RenderThemeWin::platformActiveSelectionForegroundColor() const
{
    COLORREF color = GetSysColor(COLOR_HIGHLIGHTTEXT);
    return Color(GetRValue(color), GetGValue(color), GetBValue(color), 255);
}

Color RenderThemeWin::platformInactiveSelectionForegroundColor() const
{
    return Color::white;
}

bool RenderThemeWin::supportsFocus(EAppearance appearance)
{
    switch (appearance) {
        case PushButtonAppearance:
        case DefaultButtonAppearance:
        case ButtonAppearance:
        case TextFieldAppearance:
        case TextAreaAppearance:
            return true;
        default:
            return false;
    }
}

unsigned RenderThemeWin::determineState(RenderObject* o)
{
    unsigned result = TS_NORMAL;
    if (!isEnabled(o))
        result = TS_DISABLED;
    else if (isReadOnlyControl(o))
        result = TFS_READONLY; // Readonly is supported on textfields.
    else if (supportsFocus(o->style()->appearance()) && isFocused(o))
        result = TS_FOCUSED;
    else if (isPressed(o)) // Active overrides hover.
        result = TS_ACTIVE;
    else if (isHovered(o))
        result = TS_HOVER;
    if (isChecked(o))
        result += 4; // 4 unchecked states, 4 checked states.
    return result;
}

unsigned RenderThemeWin::determineClassicState(RenderObject* o)
{
    unsigned result = 0;
    if (!isEnabled(o) || isReadOnlyControl(o))
        result = DFCS_INACTIVE;
    else if (isPressed(o)) // Active supersedes hover
        result = DFCS_PUSHED;
    else if (isHovered(o))
        result = DFCS_HOT;
    if (isChecked(o))
        result |= DFCS_CHECKED;
    return result;
}

ThemeData RenderThemeWin::getThemeData(RenderObject* o)
{
    ThemeData result;
    switch (o->style()->appearance()) {
        case PushButtonAppearance:
        case ButtonAppearance:
            result.m_part = BP_BUTTON;
            result.m_classicState = DFCS_BUTTONPUSH;
            break;
        case CheckboxAppearance:
            result.m_part = BP_CHECKBOX;
            result.m_classicState = DFCS_BUTTONCHECK;
            break;
        case RadioAppearance:
            result.m_part = BP_RADIO;
            result.m_classicState = DFCS_BUTTONRADIO;
            break;
        case ListboxAppearance:
        case MenulistAppearance:
        case TextFieldAppearance:
        case TextAreaAppearance:
            result.m_part = TFP_TEXTFIELD;
            break;
    }

    result.m_state = determineState(o);
    result.m_classicState |= determineClassicState(o);

    return result;
}

// May need to add stuff to these later, so keep the graphics context retrieval/release in some helpers.
static HDC prepareForDrawing(GraphicsContext* g, const IntRect& r)
{
    return g->getWindowsContext(r);
}
 
static void doneDrawing(GraphicsContext* g, HDC hdc, const IntRect& r)
{
    g->releaseWindowsContext(hdc, r);
}

bool RenderThemeWin::paintButton(RenderObject* o, const RenderObject::PaintInfo& i, const IntRect& r)
{
    // Get the correct theme data for a button
    ThemeData themeData = getThemeData(o);

    // Now paint the button.
    HDC hdc = prepareForDrawing(i.context, r);  
    RECT widgetRect = r;
    if (uxthemeLibrary() && !m_buttonTheme)
        m_buttonTheme = OpenThemeData(0, L"Button");
    if (m_buttonTheme)
        DrawThemeBackground(m_buttonTheme, hdc, themeData.m_part, themeData.m_state, &widgetRect, NULL);
    else {
        if ((themeData.m_part == BP_BUTTON) && isFocused(o)) {
            // Draw black focus rect around button outer edge
            HBRUSH brush = GetSysColorBrush(COLOR_3DDKSHADOW);
            if (brush) {
                FrameRect(hdc, &widgetRect, brush);
                InflateRect(&widgetRect, -1, -1);
            }
        }
        DrawFrameControl(hdc, &widgetRect, DFC_BUTTON, themeData.m_classicState);
        if ((themeData.m_part != BP_BUTTON) && isFocused(o))
            DrawFocusRect(hdc, &widgetRect);
    }
    doneDrawing(i.context, hdc, r);

    return false;
}

void RenderThemeWin::setCheckboxSize(RenderStyle* style) const
{
    // If the width and height are both specified, then we have nothing to do.
    if (!style->width().isIntrinsicOrAuto() && !style->height().isAuto())
        return;

    // FIXME:  A hard-coded size of 13 is used.  This is wrong but necessary for now.  It matches Firefox.
    // At different DPI settings on Windows, querying the theme gives you a larger size that accounts for
    // the higher DPI.  Until our entire engine honors a DPI setting other than 96, we can't rely on the theme's
    // metrics.
    if (style->width().isIntrinsicOrAuto())
        style->setWidth(Length(13, Fixed));
    if (style->height().isAuto())
        style->setHeight(Length(13, Fixed));
}

bool RenderThemeWin::paintTextField(RenderObject* o, const RenderObject::PaintInfo& i, const IntRect& r)
{
    // Get the correct theme data for a textfield
    ThemeData themeData = getThemeData(o);

    // Now paint the text field.
    HDC hdc = prepareForDrawing(i.context, r);
    RECT widgetRect = r;
    if (uxthemeLibrary() && !m_textFieldTheme)
        m_textFieldTheme = OpenThemeData(0, L"Edit");
    if (m_textFieldTheme)
        DrawThemeBackground(m_textFieldTheme, hdc, themeData.m_part, themeData.m_state, &widgetRect, NULL);
    else {
        DrawEdge(hdc, &widgetRect, EDGE_SUNKEN, BF_RECT | BF_ADJUST);
        FillRect(hdc, &widgetRect, reinterpret_cast<HBRUSH>(((themeData.m_classicState & DFCS_INACTIVE) ? COLOR_BTNFACE : COLOR_WINDOW) + 1));
    }
    doneDrawing(i.context, hdc, r);

    return false;
}

void RenderThemeWin::adjustMenuListStyle(CSSStyleSelector* selector, RenderStyle* style, Element* e) const
{
    // Height is locked to auto.
    style->setHeight(Length(Auto));

    // White-space is locked to pre
    style->setWhiteSpace(PRE);

    // Add in the padding that we'd like to use.
    const int buttonWidth = GetSystemMetrics(SM_CXVSCROLL);
    style->setPaddingLeft(Length(2, Fixed));
    style->setPaddingRight(Length(buttonWidth + 2, Fixed));
    style->setPaddingTop(Length(1, Fixed));
    style->setPaddingBottom(Length(1, Fixed));
}

bool RenderThemeWin::paintMenuList(RenderObject* o, const RenderObject::PaintInfo& i, const IntRect& r)
{
    // FIXME: All these inflate() calls are bogus, causing painting problems,
    // as well as sizing wackiness in Classic mode
    IntRect editRect(r);
    paintTextField(o, i, editRect);

    const int buttonWidth = GetSystemMetrics(SM_CXVSCROLL);
    IntRect buttonRect(r.right() - buttonWidth - 1, r.y(), buttonWidth, r.height());
    buttonRect.inflateY(-1);
    paintMenuListButton(o, i, buttonRect);

    return false;
}

bool RenderThemeWin::paintMenuListButton(RenderObject* o, const RenderObject::PaintInfo& i, const IntRect& r)
{
    HDC hdc = prepareForDrawing(i.context, r);
    RECT widgetRect = r;
    if (uxthemeLibrary() && !m_menuListTheme)
        m_menuListTheme = OpenThemeData(0, L"Combobox");
    if (m_menuListTheme)
        DrawThemeBackground(m_menuListTheme, hdc, CP_DROPDOWNBUTTON, determineState(o), &widgetRect, NULL);
    else
        DrawFrameControl(hdc, &widgetRect, DFC_SCROLL, DFCS_SCROLLCOMBOBOX | determineClassicState(o));
    doneDrawing(i.context, hdc, r);

    return false;
}

void RenderThemeWin::systemFont(int propId, FontDescription& fontDescription) const
{
    static FontDescription systemFont;
    static FontDescription smallSystemFont;
    static FontDescription menuFont;
    static FontDescription labelFont;
    static FontDescription miniControlFont;
    static FontDescription smallControlFont;
    static FontDescription controlFont;

    FontDescription* cachedDesc;
    float fontSize = 0;
    switch (propId) {
        case CSSValueSmallCaption:
            cachedDesc = &smallSystemFont;
            break;
        case CSSValueMenu:
            cachedDesc = &menuFont;
            break;
        case CSSValueStatusBar:
            cachedDesc = &labelFont;
            if (!labelFont.isAbsoluteSize())
                fontSize = 10.0f;
            break;
        case CSSValueWebkitMiniControl:
            cachedDesc = &miniControlFont;
            break;
        case CSSValueWebkitSmallControl:
            cachedDesc = &smallControlFont;
            break;
        case CSSValueWebkitControl:
            cachedDesc = &controlFont;
            break;
        default:
            cachedDesc = &systemFont;
            if (!systemFont.isAbsoluteSize())
                fontSize = 13.0f;
    }

    if (fontSize) {
        cachedDesc->setIsAbsoluteSize(true);
        cachedDesc->setGenericFamily(FontDescription::NoFamily);
        cachedDesc->firstFamily().setFamily("Lucida Grande");
        cachedDesc->setSpecifiedSize(fontSize);
        cachedDesc->setWeight(FontWeightNormal);
        cachedDesc->setItalic(false);
    }
    fontDescription = *cachedDesc;
}

} // namespace