/*******************************************************************************
 * Copyright (c) 2000, 2008 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 * Port to the D programming language:
 *     Frank Benoit <benoit@tionex.de>
 *******************************************************************************/
module org.eclipse.swt.widgets.FontDialog;

import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTException;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.FontData;
import org.eclipse.swt.graphics.PaletteData;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.internal.win32.OS;

import org.eclipse.swt.widgets.Dialog;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Display;

import java.lang.all;

/**
 * Instances of this class allow the user to select a font
 * from all available fonts in the system.
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>(none)</dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 * <p>
 * IMPORTANT: This class is intended to be subclassed <em>only</em>
 * within the SWT implementation.
 * </p>
 * 
 * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: ControlExample, Dialog tab</a>
 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
 */
public class FontDialog : Dialog {
    FontData fontData;
    RGB rgb;

/**
 * Constructs a new instance of this class given only its parent.
 *
 * @param parent a shell which will be the parent of the new instance
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
 * </ul>
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
 *    <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
 * </ul>
 */
public this (Shell parent) {
    this (parent, SWT.APPLICATION_MODAL);
}

/**
 * Constructs a new instance of this class given its parent
 * and a style value describing its behavior and appearance.
 * <p>
 * The style value is either one of the style constants defined in
 * class <code>SWT</code> which is applicable to instances of this
 * class, or must be built by <em>bitwise OR</em>'ing together
 * (that is, using the <code>int</code> "|" operator) two or more
 * of those <code>SWT</code> style constants. The class description
 * lists the style constants that are applicable to the class.
 * Style bits are also inherited from superclasses.
 * </p>
 *
 * @param parent a shell which will be the parent of the new instance
 * @param style the style of dialog to construct
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
 * </ul>
 * @exception SWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
 *    <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
 * </ul>
 */
public this (Shell parent, int style) {
    super (parent, checkStyle (parent, style));
    checkSubclass ();
}

/**
 * Returns a FontData object describing the font that was
 * selected in the dialog, or null if none is available.
 *
 * @return the FontData for the selected font, or null
 * @deprecated use #getFontList ()
 */
public FontData getFontData () {
    return fontData;
}

/**
 * Returns a FontData set describing the font that was
 * selected in the dialog, or null if none is available.
 *
 * @return the FontData for the selected font, or null
 * @since 2.1.1
 */
public FontData [] getFontList () {
    if (fontData is null) return null;
    FontData [] result = new FontData [1];
    result [0] = fontData;
    return result;
}

/**
 * Returns an RGB describing the color that was selected
 * in the dialog, or null if none is available.
 *
 * @return the RGB value for the selected color, or null
 *
 * @see PaletteData#getRGBs
 *
 * @since 2.1
 */
public RGB getRGB () {
    return rgb;
}

/**
 * Makes the dialog visible and brings it to the front
 * of the display.
 *
 * @return a FontData object describing the font that was selected,
 *         or null if the dialog was cancelled or an error occurred
 *
 * @exception SWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the dialog has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the dialog</li>
 * </ul>
 */
public FontData open () {
    static if (OS.IsWinCE) SWT.error (SWT.ERROR_NOT_IMPLEMENTED);

    /* Get the owner HWND for the dialog */
    HWND hwndOwner = parent.handle;
    auto hwndParent = parent.handle;

    /*
    * Feature in Windows.  There is no API to set the orientation of a
    * font dialog.  It is always inherited from the parent.  The fix is
    * to create a hidden parent and set the orientation in the hidden
    * parent for the dialog to inherit.
    */
    bool enabled = false;
    if (!OS.IsWinCE && OS.WIN32_VERSION >= OS.VERSION(4, 10)) {
        int dialogOrientation = style & (SWT.LEFT_TO_RIGHT | SWT.RIGHT_TO_LEFT);
        int parentOrientation = parent.style & (SWT.LEFT_TO_RIGHT | SWT.RIGHT_TO_LEFT);
        if (dialogOrientation !is parentOrientation) {
            int exStyle = OS.WS_EX_NOINHERITLAYOUT;
            if (dialogOrientation is SWT.RIGHT_TO_LEFT) exStyle |= OS.WS_EX_LAYOUTRTL;
            hwndOwner = OS.CreateWindowEx (
                exStyle,
                Shell.DialogClass.ptr,
                null,
                0,
                OS.CW_USEDEFAULT, 0, OS.CW_USEDEFAULT, 0,
                hwndParent,
                null,
                OS.GetModuleHandle (null),
                null);
            enabled = OS.IsWindowEnabled (hwndParent) !is 0;
            if (enabled) OS.EnableWindow (hwndParent, false);
        }
    }

    /* Open the dialog */
    auto hHeap = OS.GetProcessHeap ();
    CHOOSEFONT lpcf;
    lpcf.lStructSize = CHOOSEFONT.sizeof;
    lpcf.hwndOwner = hwndOwner;
    lpcf.Flags = OS.CF_SCREENFONTS | OS.CF_EFFECTS;
    auto lpLogFont = cast(LOGFONT*) OS.HeapAlloc (hHeap, OS.HEAP_ZERO_MEMORY, LOGFONT.sizeof);
    if (fontData !is null /+&& fontData.data !is null+/) {
        LOGFONT logFont = fontData.data;
        int lfHeight = logFont.lfHeight;
        auto hDC = OS.GetDC (null);
        int pixels = -cast(int)(0.5f + (fontData.height * OS.GetDeviceCaps(hDC, OS.LOGPIXELSY) / 72));
        OS.ReleaseDC (null, hDC);
        logFont.lfHeight = pixels;
        lpcf.Flags |= OS.CF_INITTOLOGFONTSTRUCT;
        OS.MoveMemory (lpLogFont, &logFont, LOGFONT.sizeof);
        logFont.lfHeight = lfHeight;
    }
    lpcf.lpLogFont = lpLogFont;
    if (rgb !is null) {
        int red = rgb.red & 0xFF;
        int green = (rgb.green << 8) & 0xFF00;
        int blue = (rgb.blue << 16) & 0xFF0000;
        lpcf.rgbColors = red | green | blue;
    }

    /* Make the parent shell be temporary modal */
    Dialog oldModal = null;
    Display display = null;
    if ((style & (SWT.APPLICATION_MODAL | SWT.SYSTEM_MODAL)) !is 0) {
        display = parent.getDisplay ();
        oldModal = display.getModalDialog ();
        display.setModalDialog (this);
    }

    /* Open the dialog */
    bool success = cast(bool) OS.ChooseFont (&lpcf);

    /* Clear the temporary dialog modal parent */
    if ((style & (SWT.APPLICATION_MODAL | SWT.SYSTEM_MODAL)) !is 0) {
        display.setModalDialog (oldModal);
    }

    /* Compute the result */
    if (success) {
        LOGFONT* logFont = lpLogFont;
        //OS.MoveMemory (logFont, lpLogFont, LOGFONT.sizeof);

        /*
         * This will not work on multiple screens or
         * for printing. Should use DC for the proper device.
         */
        auto hDC = OS.GetDC(null);
        int logPixelsY = OS.GetDeviceCaps(hDC, OS.LOGPIXELSY);
        int pixels = 0;
        if (logFont.lfHeight > 0) {
            /*
             * Feature in Windows. If the lfHeight of the LOGFONT structure
             * is positive, the lfHeight measures the height of the entire
             * cell, including internal leading, in logical units. Since the
             * height of a font in points does not include the internal leading,
             * we must subtract the internal leading, which requires a TEXTMETRIC,
             * which in turn requires font creation.
             */
            auto hFont = OS.CreateFontIndirect(logFont);
            auto oldFont = OS.SelectObject(hDC, hFont);
            TEXTMETRIC lptm ;
            OS.GetTextMetrics(hDC, &lptm);
            OS.SelectObject(hDC, oldFont);
            OS.DeleteObject(hFont);
            pixels = logFont.lfHeight - lptm.tmInternalLeading;
        } else {
            pixels = -logFont.lfHeight;
        }
        OS.ReleaseDC(null, hDC);

        float points = pixels * 72f /logPixelsY;
        fontData = FontData.win32_new (logFont, points);
        int red = lpcf.rgbColors & 0xFF;
        int green = (lpcf.rgbColors >> 8) & 0xFF;
        int blue = (lpcf.rgbColors >> 16) & 0xFF;
        rgb = new RGB (red, green, blue);
    }

    /* Free the OS memory */
    if (lpLogFont !is null) OS.HeapFree (hHeap, 0, lpLogFont);

    /* Destroy the BIDI orientation window */
    if (hwndParent !is hwndOwner) {
        if (enabled) OS.EnableWindow (hwndParent, true);
        OS.SetActiveWindow (hwndParent);
        OS.DestroyWindow (hwndOwner);
    }

    /*
    * This code is intentionally commented.  On some
    * platforms, the owner window is repainted right
    * away when a dialog window exits.  This behavior
    * is currently unspecified.
    */
//  if (hwndOwner !is 0) OS.UpdateWindow (hwndOwner);

    if (!success) return null;
    return fontData;
}

/**
 * Sets a FontData object describing the font to be
 * selected by default in the dialog, or null to let
 * the platform choose one.
 *
 * @param fontData the FontData to use initially, or null
 * @deprecated use #setFontList (FontData [])
 */
public void setFontData (FontData fontData) {
    this.fontData = fontData;
}

/**
 * Sets the set of FontData objects describing the font to
 * be selected by default in the dialog, or null to let
 * the platform choose one.
 *
 * @param fontData the set of FontData objects to use initially, or null
 *        to let the platform select a default when open() is called
 *
 * @see Font#getFontData
 *
 * @since 2.1.1
 */
public void setFontList (FontData [] fontData) {
    if (fontData !is null && fontData.length > 0) {
        this.fontData = fontData [0];
    } else {
        this.fontData = null;
    }
}

/**
 * Sets the RGB describing the color to be selected by default
 * in the dialog, or null to let the platform choose one.
 *
 * @param rgb the RGB value to use initially, or null to let
 *        the platform select a default when open() is called
 *
 * @see PaletteData#getRGBs
 *
 * @since 2.1
 */
public void setRGB (RGB rgb) {
    this.rgb = rgb;
}

}