Dave Jarvis' Repositories

/*
 * Copyright 2016 White Magic Software, Ltd.
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  o Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 *  o Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.scrivenvar.definition;

import javafx.scene.control.TreeItem;

import java.text.Normalizer;
import java.util.Stack;

import static com.scrivenvar.definition.FindMode.*;
import static java.text.Normalizer.Form.NFD;

/**
 * Provides behaviour afforded to variable names and their corresponding value.
 *
 * @param <T> The type of TreeItem (usually String).
 * @author White Magic Software, Ltd.
 */
public class VariableTreeItem<T> extends TreeItem<T> {

  /**
   * Constructs a new item with a default value.
   *
   * @param value Passed up to superclass.
   */
  public VariableTreeItem( final T value ) {
    super( value );
  }

  /**
   * Finds a leaf starting at the current node with text that matches the given
   * value.
   *
   * @param text The text to match against each leaf in the tree.
   * @return The leaf that has a value starting with the given text.
   */
  public VariableTreeItem<T> findLeaf( final String text ) {
    return findLeaf( text, STARTS_WITH );
  }

  /**
   * Finds a leaf starting at the current node with text that matches the given
   * value.
   *
   * @param text     The text to match against each leaf in the tree.
   * @param findMode What algorithm is used to match the given text.
   * @return The leaf that has a value starting with the given text.
   */
  public VariableTreeItem<T> findLeaf(
      final String text, final FindMode findMode ) {
    final Stack<VariableTreeItem<T>> stack = new Stack<>();
    final VariableTreeItem<T> root = this;

    stack.push( root );

    // Don't try to find keys for blank/empty variable values.
    boolean found = text.isBlank();
    VariableTreeItem<T> node = null;

    while( !found && !stack.isEmpty() ) {
      node = stack.pop();

      if( findMode == EXACT && node.valueEquals( text ) ) {
        found = true;
      }
      else if( findMode == CONTAINS && node.valueContains( text ) ) {
        found = true;
      }
      else if( findMode == STARTS_WITH && node.valueStartsWith( text ) ) {
        found = true;
      }
      else {
        for( final TreeItem<T> child : node.getChildren() ) {
          stack.push( (VariableTreeItem<T>) child );
        }

        // No match found, yet.
        node = null;
      }
    }

    return node;
  }

  /**
   * Returns the value of the string without diacritic marks.
   *
   * @return A non-null, possibly empty string.
   */
  private String getDiacriticlessValue() {
    final String value = getValue().toString();
    final String normalized = Normalizer.normalize( value, NFD );

    return normalized.replaceAll( "\\p{M}", "" );
  }

  /**
   * Returns true if this node is a leaf and its value starts with the given
   * text.
   *
   * @param s The text to compare against the node value.
   * @return true Node is a leaf and its value starts with the given value.
   */
  private boolean valueStartsWith( final String s ) {
    return isLeaf() && getDiacriticlessValue().startsWith( s );
  }

  /**
   * Returns true if this node is a leaf and its value contains the given text.
   *
   * @param s The text to compare against the node value.
   * @return true Node is a leaf and its value contains the given value.
   */
  private boolean valueContains( final String s ) {
    return isLeaf() && getDiacriticlessValue().contains( s );
  }

  /**
   * Returns true if this node is a leaf and its value equals the given text.
   *
   * @param s The text to compare against the node value.
   * @return true Node is a leaf and its value equals the given value.
   */
  private boolean valueEquals( final String s ) {
    return isLeaf() && getValue().equals( s );
  }

  /**
   * Returns the path for this node, with nodes made distinct using the
   * separator character. This uses two loops: one for pushing nodes onto a
   * stack and one for popping them off to create the path in desired order.
   *
   * @return A non-null string, possibly empty.
   */
  public String toPath() {
    return TreeItemAdapter.toPath( getParent() );
  }
}