/*******************************************************************************
 * Copyright (c) 2000, 2006 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 dwt.widgets.ExpandItem;

import dwt.widgets.Item;
import dwt.widgets.Widget;

import dwt.graphics.GC;
import dwt.graphics.Image;
import dwt.internal.win32.OS;
import dwt.widgets.Control;
import dwt.widgets.ExpandBar;
import dwt.widgets.Item;

import dwt.DWT;
import dwt.DWTException;
import dwt.graphics.GC;
import dwt.graphics.Image;
import dwt.graphics.Rectangle;
import dwt.internal.win32.OS;

import dwt.dwthelper.utils;

/**
 * Instances of this class represent a selectable user interface object
 * that represents a expandable item in a expand bar.
 * <p>
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>(none)</dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 * </p><p>
 * IMPORTANT: This class is <em>not</em> intended to be subclassed.
 * </p>
 *
 * @see ExpandBar
 *
 * @since 3.2
 */
public class ExpandItem : Item {
    ExpandBar parent;
    Control control;
    bool expanded, hover;
    int x, y, width, height;
    int imageHeight, imageWidth;
    static const int TEXT_INSET = 6;
    static const int BORDER = 1;
    static const int CHEVRON_SIZE = 24;

/**
 * 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>DWT</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>DWT</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 composite control which will be the parent of the new instance (cannot be null)
 * @param style the style of control to construct
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
 * </ul>
 * @exception DWTException <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>
 *
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public this (ExpandBar parent, int style) {
    this (parent, style, checkNull (parent).getItemCount ());
}

/**
 * Constructs a new instance of this class given its parent, a
 * style value describing its behavior and appearance, and the index
 * at which to place it in the items maintained by its parent.
 * <p>
 * The style value is either one of the style constants defined in
 * class <code>DWT</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>DWT</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 composite control which will be the parent of the new instance (cannot be null)
 * @param style the style of control to construct
 * @param index the zero-relative index to store the receiver in its parent
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
 *    <li>ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the parent (inclusive)</li>
 * </ul>
 * @exception DWTException <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>
 *
 * @see Widget#checkSubclass
 * @see Widget#getStyle
 */
public this (ExpandBar parent, int style, int index) {
    super (parent, style);
    this.parent = parent;
    parent.createItem (this, style, index);
}

static ExpandBar checkNull (ExpandBar control) {
    if (control is null) DWT.error (DWT.ERROR_NULL_ARGUMENT);
    return control;
}

private void drawChevron (HDC hDC, RECT* rect) {
    HBRUSH oldBrush = OS.SelectObject (hDC, OS.GetSysColorBrush (OS.COLOR_BTNFACE));
    OS.PatBlt (hDC, rect.left, rect.top, rect.right - rect.left, rect.bottom - rect.top, OS.PATCOPY);
    OS.SelectObject (hDC, oldBrush);
    rect.left += 4;
    rect.top += 4;
    rect.right -= 4;
    rect.bottom -= 4;
    HPEN hPen = OS.CreatePen (OS.PS_SOLID, 1, parent.foreground);
    HPEN oldPen = OS.SelectObject (hDC, hPen);
    int [] polyline1, polyline2;
    if (expanded) {
        int px = rect.left + 5;
        int py = rect.top + 7;
        polyline1 = [
                px,py, px+1,py, px+1,py-1, px+2,py-1, px+2,py-2, px+3,py-2, px+3,py-3,
                px+3,py-2, px+4,py-2, px+4,py-1, px+5,py-1, px+5,py, px+7,py];
        py += 4;
        polyline2 = [
                px,py, px+1,py, px+1,py-1, px+2,py-1, px+2,py-2, px+3,py-2, px+3,py-3,
                px+3,py-2, px+4,py-2, px+4,py-1,  px+5,py-1, px+5,py, px+7,py];
    } else {
        int px = rect.left + 5;
        int py = rect.top + 4;
        polyline1 = [
                px,py, px+1,py, px+1,py+1, px+2,py+1, px+2,py+2, px+3,py+2, px+3,py+3,
                px+3,py+2, px+4,py+2, px+4,py+1,  px+5,py+1, px+5,py, px+7,py];
        py += 4;
        polyline2 = [
                px,py, px+1,py, px+1,py+1, px+2,py+1, px+2,py+2, px+3,py+2, px+3,py+3,
                px+3,py+2, px+4,py+2, px+4,py+1,  px+5,py+1, px+5,py, px+7,py];
    }
    OS.Polyline (hDC, cast(POINT*)polyline1.ptr, polyline1.length / 2);
    OS.Polyline (hDC, cast(POINT*)polyline2.ptr, polyline2.length / 2);
    if (hover) {
        HPEN whitePen = OS.CreatePen (OS.PS_SOLID, 1, OS.GetSysColor (OS.COLOR_3DHILIGHT));
        HPEN darkGrayPen = OS.CreatePen (OS.PS_SOLID, 1, OS.GetSysColor (OS.COLOR_3DSHADOW));
        OS.SelectObject (hDC, whitePen);
        int [] points1 = [
                rect.left, rect.bottom,
                rect.left, rect.top,
                rect.right, rect.top];
        OS.Polyline (hDC, cast(POINT*)points1.ptr, points1.length / 2);
        OS.SelectObject (hDC, darkGrayPen);
        int [] points2 = [
                rect.right, rect.top,
                rect.right, rect.bottom,
                rect.left, rect.bottom];
        OS.Polyline (hDC, cast(POINT*)points2.ptr, points2.length / 2);
        OS.SelectObject (hDC, oldPen);
        OS.DeleteObject (whitePen);
        OS.DeleteObject (darkGrayPen);
    } else {
        OS.SelectObject (hDC, oldPen);
    }
    OS.DeleteObject (hPen);
}

void drawItem (GC gc, HTHEME hTheme, RECT* clipRect, bool drawFocus) {
    auto hDC = gc.handle;
    int headerHeight = parent.getBandHeight ();
    RECT rect;
    OS.SetRect (&rect, x, y, x + width, y + headerHeight);
    if (hTheme !is null) {
        OS.DrawThemeBackground (hTheme, hDC, OS.EBP_NORMALGROUPHEAD, 0, &rect, clipRect);
    } else {
        HBRUSH oldBrush = OS.SelectObject (hDC, OS.GetSysColorBrush (OS.COLOR_BTNFACE));
        OS.PatBlt (hDC, rect.left, rect.top, rect.right - rect.left, rect.bottom - rect.top, OS.PATCOPY);
        OS.SelectObject (hDC, oldBrush);
    }
    if (image !is null) {
        rect.left += ExpandItem.TEXT_INSET;
        if (imageHeight > headerHeight) {
            gc.drawImage (image, rect.left, rect.top + headerHeight - imageHeight);
        } else {
            gc.drawImage (image, rect.left, rect.top + (headerHeight - imageHeight) / 2);
        }
        rect.left += imageWidth;
    }
    if (text.length > 0) {
        rect.left += ExpandItem.TEXT_INSET;
        TCHAR[] buffer = StrToTCHARs ( text/+, parent.getCodePage ()+/ );
        if (hTheme !is null) {
            OS.DrawThemeText (hTheme, hDC, OS.EBP_NORMALGROUPHEAD, 0, buffer.ptr, buffer.length, OS.DT_VCENTER | OS.DT_SINGLELINE, 0, &rect);
        } else {
            int oldBkMode = OS.SetBkMode (hDC, OS.TRANSPARENT);
            OS.DrawText (hDC, buffer.ptr, buffer.length, &rect, OS.DT_VCENTER | OS.DT_SINGLELINE);
            OS.SetBkMode (hDC, oldBkMode);
        }
    }
    int chevronSize = ExpandItem.CHEVRON_SIZE;
    rect.left = rect.right - chevronSize;
    rect.top = y + (headerHeight - chevronSize) / 2;
    rect.bottom = rect.top + chevronSize;
    if (hTheme !is null) {
        int partID = expanded ? OS.EBP_NORMALGROUPCOLLAPSE : OS.EBP_NORMALGROUPEXPAND;
        int stateID = hover ? OS.EBNGC_HOT : OS.EBNGC_NORMAL;
        OS.DrawThemeBackground (hTheme, hDC, partID, stateID, &rect, clipRect);
    } else {
        drawChevron (hDC, &rect);
    }
    if (drawFocus) {
        OS.SetRect (&rect, x + 1, y + 1, x + width - 2, y + headerHeight - 2);
        OS.DrawFocusRect (hDC, &rect);
    }
    if (expanded) {
        if (!parent.isAppThemed ()) {
            HPEN pen = OS.CreatePen (OS.PS_SOLID, 1, OS.GetSysColor (OS.COLOR_BTNFACE));
            HPEN oldPen = OS.SelectObject (hDC, pen);
            int [] points = [
                    x, y + headerHeight,
                    x, y + headerHeight + height,
                    x + width - 1, y + headerHeight + height,
                    x + width - 1, y + headerHeight - 1];
            OS.Polyline (hDC, cast(POINT*) points.ptr, points.length / 2);
            OS.SelectObject (hDC, oldPen);
            OS.DeleteObject (pen);
        }
    }
}

override void destroyWidget () {
    parent.destroyItem (this);
    releaseHandle ();
}

/**
 * Returns the control that is shown when the item is expanded.
 * If no control has been set, return <code>null</code>.
 *
 * @return the control
 *
 * @exception DWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public Control getControl () {
    checkWidget ();
    return control;
}

/**
 * Returns <code>true</code> if the receiver is expanded,
 * and false otherwise.
 *
 * @return the expanded state
 *
 * @exception DWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public bool getExpanded () {
    checkWidget ();
    return expanded;
}

/**
 * Returns the height of the receiver's header
 *
 * @return the height of the header
 *
 * @exception DWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public int getHeaderHeight () {
    checkWidget ();
    return Math.max (parent.getBandHeight (), imageHeight);
}

/**
 * Gets the height of the receiver.
 *
 * @return the height
 *
 * @exception DWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public int getHeight () {
    checkWidget ();
    return height;
}

/**
 * Returns the receiver's parent, which must be a <code>ExpandBar</code>.
 *
 * @return the receiver's parent
 *
 * @exception DWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public ExpandBar getParent () {
    checkWidget ();
    return parent;
}

int getPreferredWidth (HTHEME hTheme, HDC hDC) {
    int width = ExpandItem.TEXT_INSET * 2 + ExpandItem.CHEVRON_SIZE;
    if (image !is null) {
        width += ExpandItem.TEXT_INSET + imageWidth;
    }
    if (text.length > 0) {
        RECT rect;
        TCHAR[] buffer = StrToTCHARs (/+parent.getCodePage (),+/ text);
        if (hTheme !is null) {
            OS.GetThemeTextExtent (hTheme, hDC, OS.EBP_NORMALGROUPHEAD, 0, buffer.ptr, buffer.length, OS.DT_SINGLELINE, null, &rect);
        } else {
            OS.DrawText (hDC, buffer.ptr, buffer.length, &rect, OS.DT_CALCRECT);
        }
        width += (rect.right - rect.left);
    }
    return width;
}

bool isHover (int x, int y) {
    int bandHeight = parent.getBandHeight ();
    return this.x < x && x < (this.x + width) && this.y < y && y < (this.y + bandHeight);
}

void redraw (bool all) {
    auto parentHandle = parent.handle;
    int headerHeight = parent.getBandHeight ();
    RECT rect;
    int left = all ? x : x + width - headerHeight;
    OS.SetRect (&rect, left, y, x + width, y + headerHeight);
    OS.InvalidateRect (parentHandle, &rect, true);
    if (imageHeight > headerHeight) {
        OS.SetRect (&rect, x + ExpandItem.TEXT_INSET, y + headerHeight - imageHeight, x + ExpandItem.TEXT_INSET + imageWidth, y);
        OS.InvalidateRect (parentHandle, &rect, true);
    }
    if (!parent.isAppThemed ()) {
        OS.SetRect (&rect, x, y + headerHeight, x + width, y + headerHeight + height + 1);
        OS.InvalidateRect (parentHandle, &rect, true);
    }
}

override void releaseHandle () {
    super.releaseHandle ();
    parent = null;
}

override void releaseWidget () {
    super.releaseWidget ();
    control = null;
}

void setBounds (int x, int y, int width, int height, bool move, bool size) {
    redraw (true);
    int headerHeight = parent.getBandHeight ();
    if (move) {
        if (imageHeight > headerHeight) {
            y += (imageHeight - headerHeight);
        }
        this.x = x;
        this.y = y;
        redraw (true);
    }
    if (size) {
        this.width = width;
        this.height = height;
        redraw (true);
    }
    if (control !is null && !control.isDisposed ()) {
        if (!parent.isAppThemed ()) {
            x += BORDER;
            width = Math.max (0, width - BORDER * 2);
            height = Math.max (0, height - BORDER);
        }
        if (move && size) control.setBounds (x, y + headerHeight, width, height);
        if (move && !size) control.setLocation (x, y + headerHeight);
        if (!move && size) control.setSize (width, height);
    }
}

/**
 * Sets the control that is shown when the item is expanded.
 *
 * @param control the new control (or null)
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_INVALID_ARGUMENT - if the control has been disposed</li>
 *    <li>ERROR_INVALID_PARENT - if the control is not in the same widget tree</li>
 * </ul>
 * @exception DWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public void setControl (Control control) {
    checkWidget ();
    if (control !is null) {
        if (control.isDisposed ()) error (DWT.ERROR_INVALID_ARGUMENT);
        if (control.parent !is parent) error (DWT.ERROR_INVALID_PARENT);
    }
    this.control = control;
    if (control !is null) {
        int headerHeight = parent.getBandHeight ();
        control.setVisible (expanded);
        if (!parent.isAppThemed ()) {
            int width = Math.max (0, this.width - BORDER * 2);
            int height = Math.max (0, this.height - BORDER);
            control.setBounds (x + BORDER, y + headerHeight, width, height);
        } else {
            control.setBounds (x, y + headerHeight, width, height);
        }
    }
}

/**
 * Sets the expanded state of the receiver.
 *
 * @param expanded the new expanded state
 *
 * @exception DWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public void setExpanded (bool expanded) {
    checkWidget ();
    this.expanded = expanded;
    parent.showItem (this);
}

/**
 * Sets the height of the receiver. This is height of the item when it is expanded,
 * excluding the height of the header.
 *
 * @param height the new height
 *
 * @exception DWTException <ul>
 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
 * </ul>
 */
public void setHeight (int height) {
    checkWidget ();
    if (height < 0) return;
    setBounds (0, 0, width, height, false, true);
    if (expanded) parent.layoutItems (parent.indexOf (this) + 1, true);
}

override public void setImage (Image image) {
    super.setImage (image);
    int oldImageHeight = imageHeight;
    if (image !is null) {
        Rectangle bounds = image.getBounds ();
        imageHeight = bounds.height;
        imageWidth = bounds.width;
    } else {
        imageHeight = imageWidth = 0;
    }
    if (oldImageHeight !is imageHeight) {
        parent.layoutItems (parent.indexOf (this), true);
    } else {
        redraw (true);
    }
}

override public void setText (String string) {
    super.setText (string);
    redraw (true);
}
}