package ij.gui;
import java.awt.*;
import ij.*;

/** This is a custom layout manager that supports resizing of zoomed
images. It's based on FlowLayout, but with vertical and centered flow. */
public class ImageLayout implements LayoutManager {

    int hgap = ImageWindow.HGAP;
    int vgap = ImageWindow.VGAP;
	ImageCanvas ic;
	boolean ignoreNonImageWidths;

    /** Creates a new ImageLayout with center alignment. */
    public ImageLayout(ImageCanvas ic) {
    	this.ic = ic;
    }

    /** Not used by this class. */
    public void addLayoutComponent(String name, Component comp) {
    }

    /** Not used by this class. */
    public void removeLayoutComponent(Component comp) {
    }

    /** Returns the preferred dimensions for this layout. */
    public Dimension preferredLayoutSize(Container target) {
		Dimension dim = new Dimension(0,0);
		int nmembers = target.getComponentCount();
		for (int i=0; i0) dim.height += vgap;
			dim.height += d.height;
		}
		Insets insets = target.getInsets();
		dim.width += insets.left + insets.right + hgap*2;
		dim.height += insets.top + insets.bottom + vgap*2;
		return dim;
    }

    /** Returns the minimum dimensions for this layout. */
    public Dimension minimumLayoutSize(Container target) {
		return preferredLayoutSize(target);
    }

    /** Determines whether to ignore the width of non-image components when calculating
     *  the preferred width (default false, i.e. the maximum of the widths of all components is used).
     *  When true, components that do not fit the window will be truncated at the right.
     *  The width of the 0th component (the ImageCanvas) is always taken into account. */
	public void ignoreNonImageWidths(boolean ignoreNonImageWidths) {
		this.ignoreNonImageWidths = ignoreNonImageWidths;
	}

    /** Centers the elements in the specified column, if there is any slack.*/
    private void moveComponents(Container target, int x, int y, int width, int height, int nmembers) {
    	int x2 = 0;
	    y += height / 2;
		for (int i=0; i60)
		    	x2 = x + (width - d.width)/2;
			m.setLocation(x2, y);
			y += vgap + d.height;
		}
    }

    /** Lays out the container and calls ImageCanvas.resizeCanvas()
		to adjust the image canvas size as needed. */
    public void layoutContainer(Container target) {
		Insets insets = target.getInsets();
		int nmembers = target.getComponentCount();
		Dimension d;
		int extraHeight = 0;
		for (int i=1; i 0) y += vgap;
			y += d.height;
			if (i==0 || !ignoreNonImageWidths)
				colw = Math.max(colw, d.width);
		}
		moveComponents(target, x, insets.top + vgap, colw, maxheight - y, nmembers);
    }
    
}