platform/platform-impl/src/com/intellij/ide/CustomHrView.java

/*
 * @(#)HRuleView.java	1.33 05/11/17
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package com.intellij.ide;

import java.awt.*;
import javax.swing.event.DocumentEvent;
import javax.swing.text.*;
import javax.swing.text.html.CSS;
import javax.swing.text.html.HTML;
import javax.swing.text.html.HTMLDocument;
import javax.swing.text.html.StyleSheet;
import java.util.Enumeration;
import java.lang.Integer;

/**
 * A view implementation to display an html horizontal
 * rule.
 *
 * @author Timothy Prinzing
 * @author Sara Swanson
 * @version 1.33 11/17/05
 */
class CustomHrView extends View {

  private Color myColor;

  /**
   * Creates a new view that represents an <hr> element.
   *
   * @param elem the element to create a view for
   */
  public CustomHrView(Element elem, Color color) {
    super(elem);
    myColor = color;
  }


  public void paint(Graphics g, Shape a) {
    Rectangle alloc = (a instanceof Rectangle) ? (Rectangle)a : a.getBounds();
    int x = 0;
    int y = alloc.y + SPACE_ABOVE + (int)topMargin;
    int width = alloc.width - (int)(leftMargin + rightMargin);
    int height = 1;
    if (size > 0) height = size;

    // Align the rule horizontally.
    switch (alignment) {
      case StyleConstants.ALIGN_CENTER:
        x = alloc.x + (alloc.width / 2) - (width / 2);
        break;
      case StyleConstants.ALIGN_RIGHT:
        x = alloc.x + alloc.width - width - (int)rightMargin;
        break;
      case StyleConstants.ALIGN_LEFT:
      default:
        x = alloc.x + (int)leftMargin;
        break;
    }

    // Paint either a shaded rule or a solid line.
    if (noshade != null) {
      g.setColor(myColor);
      g.fillRect(x, y, width, height);
    }
    else {
      Color bg = getContainer().getBackground();
      Color bottom, top;
      if (bg == null || bg.equals(Color.white)) {
        top = Color.darkGray;
        bottom = Color.lightGray;
      }
      else {
        top = Color.darkGray;
        bottom = Color.white;
      }
      g.setColor(bottom);
      g.drawLine(x + width - 1, y, x + width - 1, y + height - 1);
      g.drawLine(x, y + height - 1, x + width - 1, y + height - 1);
      g.setColor(top);
      g.drawLine(x, y, x + width - 1, y);
      g.drawLine(x, y, x, y + height - 1);
    }

  }


  /**
   * Calculates the desired shape of the rule... this is
   * basically the preferred size of the border.
   *
   * @param axis may be either X_AXIS or Y_AXIS
   * @return the desired span
   * @see View#getPreferredSpan
   */
  public float getPreferredSpan(int axis) {
    switch (axis) {
      case View.X_AXIS:
        return 1;
      case View.Y_AXIS:
        if (size > 0) {
          return size + SPACE_ABOVE + SPACE_BELOW + topMargin + bottomMargin;
        }
        else {
          if (noshade != null) {
            return 2 + SPACE_ABOVE + SPACE_BELOW + topMargin + bottomMargin;
          }
          else {
            return SPACE_ABOVE + SPACE_BELOW + topMargin + bottomMargin;
          }
        }
      default:
        throw new IllegalArgumentException("Invalid axis: " + axis);
    }
  }

  /**
   * Gets the resize weight for the axis.
   * The rule is: rigid vertically and flexible horizontally.
   *
   * @param axis may be either X_AXIS or Y_AXIS
   * @return the weight
   */
  public int getResizeWeight(int axis) {
    if (axis == View.X_AXIS) {
      return 1;
    }
    else if (axis == View.Y_AXIS) {
      return 0;
    }
    else {
      return 0;
    }
  }

  /**
   * Determines how attractive a break opportunity in
   * this view is.  This is implemented to request a forced break.
   *
   * @param axis may be either View.X_AXIS or View.Y_AXIS
   * @param pos  the potential location of the start of the
   *             broken view (greater than or equal to zero).
   *             This may be useful for calculating tab
   *             positions.
   * @param len  specifies the relative length from <em>pos</em>
   *             where a potential break is desired. The value must be greater
   *             than or equal to zero.
   * @return the weight, which should be a value between
   *         ForcedBreakWeight and BadBreakWeight.
   */
  public int getBreakWeight(int axis, float pos, float len) {
    if (axis == X_AXIS) {
      return ForcedBreakWeight;
    }
    return BadBreakWeight;
  }

  public View breakView(int axis, int offset, float pos, float len) {
    return null;
  }

  /**
   * Provides a mapping from the document model coordinate space
   * to the coordinate space of the view mapped to it.
   *
   * @param pos the position to convert
   * @param a   the allocated region to render into
   * @return the bounding box of the given position
   * @throws BadLocationException if the given position does not
   *                              represent a valid location in the associated document
   * @see View#modelToView
   */
  public Shape modelToView(int pos, Shape a, Position.Bias b) throws BadLocationException {
    int p0 = getStartOffset();
    int p1 = getEndOffset();
    if ((pos >= p0) && (pos <= p1)) {
      Rectangle r = a.getBounds();
      if (pos == p1) {
        r.x += r.width;
      }
      r.width = 0;
      return r;
    }
    return null;
  }

  /**
   * Provides a mapping from the view coordinate space to the logical
   * coordinate space of the model.
   *
   * @param x the X coordinate
   * @param y the Y coordinate
   * @param a the allocated region to render into
   * @return the location within the model that best represents the
   *         given point of view
   * @see View#viewToModel
   */
  public int viewToModel(float x, float y, Shape a, Position.Bias[] bias) {
    Rectangle alloc = (Rectangle)a;
    if (x < alloc.x + (alloc.width / 2)) {
      bias[0] = Position.Bias.Forward;
      return getStartOffset();
    }
    bias[0] = Position.Bias.Backward;
    return getEndOffset();
  }

  /**
   * Fetches the attributes to use when rendering.  This is
   * implemented to multiplex the attributes specified in the
   * model with a StyleSheet.
   */
  public AttributeSet getAttributes() {
    return attr;
  }

  // --- variables ------------------------------------------------

  private float topMargin;
  private float bottomMargin;
  private float leftMargin;
  private float rightMargin;
  private int alignment = StyleConstants.ALIGN_CENTER;
  private String noshade = "true";
  private int size = 0;

  private static final int SPACE_ABOVE = 3;
  private static final int SPACE_BELOW = 3;

  /**
   * View Attributes.
   */
  private AttributeSet attr;
}