content: /*
   * Copyright 2019 FormDev Software GmbH
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package themeengine.include.com.formdev.flatlaf.ui;
  
  import java.awt.Color;
  import java.awt.Component;
  import java.awt.Container;
  import java.awt.Dimension;
  import java.awt.Graphics;
  import java.awt.Graphics2D;
  import java.awt.Insets;
  import java.awt.Rectangle;
  import java.awt.geom.Rectangle2D;
  import java.util.Objects;
  import javax.swing.Icon;
  import javax.swing.JComponent;
  import javax.swing.JLabel;
  import javax.swing.JScrollPane;
  import javax.swing.JTable;
  import javax.swing.SwingConstants;
  import javax.swing.UIManager;
  import javax.swing.border.Border;
  import javax.swing.plaf.ComponentUI;
  import javax.swing.plaf.UIResource;
  import javax.swing.plaf.basic.BasicTableHeaderUI;
  import javax.swing.table.TableCellRenderer;
  import javax.swing.table.TableColumn;
  import javax.swing.table.TableColumnModel;
  import themeengine.include.com.formdev.flatlaf.util.UIScale;
  
  /**
   * Provides the Flat LaF UI delegate for {@link javax.swing.table.JTableHeader}.
   *
   * <!-- BasicTableHeaderUI -->
   *
   * @uiDefault TableHeader.font					Font
   * @uiDefault TableHeader.background			Color
   * @uiDefault TableHeader.foreground			Color
   *
   * <!-- FlatTableHeaderUI -->
   *
   * @uiDefault TableHeader.separatorColor		Color
   * @uiDefault TableHeader.bottomSeparatorColor	Color
   * @uiDefault TableHeader.height				int
   * @uiDefault TableHeader.sortIconPosition		String	right (default), left, top or bottom
   *
   * @author Karl Tauber
   */
  public class FlatTableHeaderUI
  	extends BasicTableHeaderUI
  {
  	protected Color separatorColor;
  	protected Color bottomSeparatorColor;
  	protected int height;
  	protected int sortIconPosition;
  
  	public static ComponentUI createUI( JComponent c ) {
  		return new FlatTableHeaderUI();
  	}
  
  	@Override
  	protected void installDefaults() {
  		super.installDefaults();
  
  		separatorColor = UIManager.getColor( "TableHeader.separatorColor" );
  		bottomSeparatorColor = UIManager.getColor( "TableHeader.bottomSeparatorColor" );
  		height = UIManager.getInt( "TableHeader.height" );
  		switch( Objects.toString( UIManager.getString( "TableHeader.sortIconPosition" ), "right" ) ) {
  			default:
  			case "right":	sortIconPosition = SwingConstants.RIGHT; break;
  			case "left":	sortIconPosition = SwingConstants.LEFT; break;
  			case "top":		sortIconPosition = SwingConstants.TOP; break;
  			case "bottom":	sortIconPosition = SwingConstants.BOTTOM; break;
  		}
  	}
  
  	@Override
  	protected void uninstallDefaults() {
  		super.uninstallDefaults();
  
  		separatorColor = null;
  		bottomSeparatorColor = null;
  	}
  
  	@Override
  	public void paint( Graphics g, JComponent c ) {
  		// do not paint borders if JTableHeader.setDefaultRenderer() was used
  		TableCellRenderer defaultRenderer = header.getDefaultRenderer();
  		boolean paintBorders = isSystemDefaultRenderer( defaultRenderer );
  		if( !paintBorders && header.getColumnModel().getColumnCount() > 0 ) {
  			// check whether the renderer delegates to the system default renderer
  			Component rendererComponent = defaultRenderer.getTableCellRendererComponent(
  				header.getTable(), "", false, false, -1, 0 );
  			paintBorders = isSystemDefaultRenderer( rendererComponent );
  		}
  
  		if( paintBorders )
  			paintColumnBorders( g, c );
  
  		// temporary use own default renderer if necessary
  		FlatTableCellHeaderRenderer sortIconRenderer = null;
  		if( sortIconPosition != SwingConstants.RIGHT ) {
  			sortIconRenderer = new FlatTableCellHeaderRenderer( header.getDefaultRenderer() );
  			header.setDefaultRenderer( sortIconRenderer );
  		}
  
  		// paint header
  		super.paint( g, c );
  
  		// restore default renderer
  		if( sortIconRenderer != null ) {
  			sortIconRenderer.reset();
  			header.setDefaultRenderer( sortIconRenderer.delegate );
  		}
  
  		if( paintBorders )
  			paintDraggedColumnBorders( g, c );
  	}
  
  	private boolean isSystemDefaultRenderer( Object headerRenderer ) {
  		String rendererClassName = headerRenderer.getClass().getName();
  		return rendererClassName.equals( "sun.swing.table.DefaultTableCellHeaderRenderer" ) ||
  			   rendererClassName.equals( "sun.swing.FilePane$AlignableTableHeaderRenderer" );
  	}
  
  	private void paintColumnBorders( Graphics g, JComponent c ) {
  		int width = c.getWidth();
  		int height = c.getHeight();
  		float lineWidth = UIScale.scale( 1f );
  		float topLineIndent = lineWidth;
  		float bottomLineIndent = lineWidth * 3;
  		TableColumnModel columnModel = header.getColumnModel();
  		int columnCount = columnModel.getColumnCount();
  
  		Graphics2D g2 = (Graphics2D) g.create();
  		try {
  			FlatUIUtils.setRenderingHints( g2 );
  
  			// paint bottom line
  			g2.setColor( bottomSeparatorColor );
  			g2.fill( new Rectangle2D.Float( 0, height - lineWidth, width, lineWidth ) );
  
  			// paint column separator lines
  			g2.setColor( separatorColor );
  
  			int sepCount = columnCount;
  			if( header.getTable() != null && header.getTable().getAutoResizeMode() != JTable.AUTO_RESIZE_OFF && !isVerticalScrollBarVisible() )
  				sepCount--;
  
  			if( header.getComponentOrientation().isLeftToRight() ) {
  				int x = 0;
  				for( int i = 0; i < sepCount; i++ ) {
  					x += columnModel.getColumn( i ).getWidth();
  					g2.fill( new Rectangle2D.Float( x - lineWidth, topLineIndent, lineWidth, height - bottomLineIndent ) );
  				}
  			} else {
  				int x = width;
  				for( int i = 0; i < sepCount; i++ ) {
  					x -= columnModel.getColumn( i ).getWidth();
  					g2.fill( new Rectangle2D.Float( x - (i < sepCount - 1 ? lineWidth : 0),
  						topLineIndent, lineWidth, height - bottomLineIndent ) );
  				}
  			}
  		} finally {
  			g2.dispose();
  		}
  	}
  
  	private void paintDraggedColumnBorders( Graphics g, JComponent c ) {
  		TableColumn draggedColumn = header.getDraggedColumn();
  		if( draggedColumn == null )
  			return;
  
  		// find index of dragged column
  		TableColumnModel columnModel = header.getColumnModel();
  		int columnCount = columnModel.getColumnCount();
  		int draggedColumnIndex = -1;
  		for( int i = 0; i < columnCount; i++ ) {
  			if( columnModel.getColumn( i ) == draggedColumn ) {
  				draggedColumnIndex = i;
  				break;
  			}
  		}
  
  		if( draggedColumnIndex < 0 )
  			return;
  
  		float lineWidth = UIScale.scale( 1f );
  		float topLineIndent = lineWidth;
  		float bottomLineIndent = lineWidth * 3;
  		Rectangle r = header.getHeaderRect( draggedColumnIndex );
  		r.x += header.getDraggedDistance();
  
  		Graphics2D g2 = (Graphics2D) g.create();
  		try {
  			FlatUIUtils.setRenderingHints( g2 );
  
  			// paint dragged bottom line
  			g2.setColor( bottomSeparatorColor );
  			g2.fill( new Rectangle2D.Float( r.x, r.y + r.height - lineWidth, r.width, lineWidth ) );
  
  			// paint dragged column separator lines
  			g2.setColor( separatorColor );
  			g2.fill( new Rectangle2D.Float( r.x, topLineIndent, lineWidth, r.height - bottomLineIndent ) );
  			g2.fill( new Rectangle2D.Float( r.x + r.width - lineWidth, r.y + topLineIndent, lineWidth, r.height - bottomLineIndent ) );
  		} finally {
  			g2.dispose();
  		}
  	}
  
  	@Override
  	public Dimension getPreferredSize( JComponent c ) {
  		Dimension size = super.getPreferredSize( c );
  		if( size.height > 0 )
  			size.height = Math.max( size.height, UIScale.scale( height ) );
  		return size;
  	}
  
  	private boolean isVerticalScrollBarVisible() {
  		JScrollPane scrollPane = getScrollPane();
  		return (scrollPane != null && scrollPane.getVerticalScrollBar() != null)
  			? scrollPane.getVerticalScrollBar().isVisible()
  			: false;
  	}
  
  	private JScrollPane getScrollPane() {
  		Container parent = header.getParent();
  		if( parent == null )
  			return null;
  
  		parent = parent.getParent();
  		return (parent instanceof JScrollPane) ? (JScrollPane) parent : null;
  	}
  
  	//---- class FlatTableCellHeaderRenderer ----------------------------------
  
  	/**
  	 * A delegating header renderer that is only used to paint sort arrows at
  	 * top, bottom or left position.
  	 */
  	private class FlatTableCellHeaderRenderer
  		implements TableCellRenderer, Border, UIResource
  	{
  		private final TableCellRenderer delegate;
  
  		private JLabel l;
  		private int oldHorizontalTextPosition = -1;
  		private Border origBorder;
  		private Icon sortIcon;
  
  		FlatTableCellHeaderRenderer( TableCellRenderer delegate ) {
  			this.delegate = delegate;
  		}
  
  		@Override
  		public Component getTableCellRendererComponent( JTable table, Object value, boolean isSelected,
  			boolean hasFocus, int row, int column )
  		{
  			Component c = delegate.getTableCellRendererComponent( table, value, isSelected, hasFocus, row, column );
  			if( !(c instanceof JLabel) )
  				return c;
  
  			l = (JLabel) c;
  
  			if( sortIconPosition == SwingConstants.LEFT ) {
  				if( oldHorizontalTextPosition < 0 )
  					oldHorizontalTextPosition = l.getHorizontalTextPosition();
  				l.setHorizontalTextPosition( SwingConstants.RIGHT );
  			} else {
  				// top or bottom
  				sortIcon = l.getIcon();
  				origBorder = l.getBorder();
  				l.setIcon( null );
  				l.setBorder( this );
  			}
  
  			return l;
  		}
  
  		void reset() {
  			if( l != null && sortIconPosition == SwingConstants.LEFT && oldHorizontalTextPosition >= 0 )
  				l.setHorizontalTextPosition( oldHorizontalTextPosition );
  		}
  
  		@Override
  		public void paintBorder( Component c, Graphics g, int x, int y, int width, int height ) {
  			if( origBorder != null )
  				origBorder.paintBorder( c, g, x, y, width, height );
  
  			if( sortIcon != null ) {
  				int xi = x + ((width - sortIcon.getIconWidth()) / 2);
  				int yi = (sortIconPosition == SwingConstants.TOP)
  					? y + UIScale.scale( 1 )
  					: y + height - sortIcon.getIconHeight()
  						- 1 // for gap
  						- (int) (1 * UIScale.getUserScaleFactor()); // for bottom border
  				sortIcon.paintIcon( c, g, xi, yi );
  			}
  		}
  
  		@Override
  		public Insets getBorderInsets( Component c ) {
  			return (origBorder != null) ? origBorder.getBorderInsets( c ) : new Insets( 0, 0, 0, 0 );
  		}
  
  		@Override
  		public boolean isBorderOpaque() {
  			return (origBorder != null) ? origBorder.isBorderOpaque() : false;
  		}
  	}
  }
  