javaparser-core/src/main/java/com/github/javaparser/printer/lexicalpreservation/NodeText.java

/*
 * Copyright (C) 2007-2010 Júlio Vilmar Gesser.
 * Copyright (C) 2011, 2013-2016 The JavaParser Team.
 *
 * This file is part of JavaParser.
 *
 * JavaParser can be used either under the terms of
 * a) the GNU Lesser General Public License as published by
 *     the Free Software Foundation, either version 3 of the License, or
 *     (at your option) any later version.
 * b) the terms of the Apache License
 *
 * You should have received a copy of both licenses in LICENCE.LGPL and
 * LICENCE.APACHE. Please refer to those files for details.
 *
 * JavaParser is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 */

package com.github.javaparser.printer.lexicalpreservation;

import com.github.javaparser.ast.Node;

import java.util.LinkedList;
import java.util.List;

/**
 * This contains the lexical information for a single node.
 * It is basically a list of tokens and children.
 */
class NodeText {
    private final List<TextElement> elements;

    public static final int NOT_FOUND = -1;

    enum Option {
        REMOVE_SPACE_IMMEDIATELY_AFTER,
        EXCLUDE_START,
        EXCLUDE_END
    }

    //
    // Constructors
    //

    NodeText(List<TextElement> elements) {
        this.elements = elements;
    }

    /**
     * Initialize with an empty list of elements.
     */
    NodeText() {
        this(new LinkedList<>());
    }

    //
    // Adding elements
    //

    /**
     * Add an element at the end.
     */
    void addElement(TextElement nodeTextElement) {
        this.elements.add(nodeTextElement);
    }

    /**
     * Add an element at the given position.
     */
    void addElement(int index, TextElement nodeTextElement) {
        this.elements.add(index, nodeTextElement);
    }

    void addChild(Node child) {
        addElement(new ChildTextElement(child));
    }

    void addChild(int index, Node child) {
        addElement(index, new ChildTextElement(child));
    }

    void addToken(int tokenKind, String text) {
        elements.add(new TokenTextElement(tokenKind, text));
    }

    void addToken(int index, int tokenKind, String text) {
        elements.add(index, new TokenTextElement(tokenKind, text));
    }

    //
    // Finding elements
    //

    int findElement(TextElementMatcher matcher) {
        return findElement(matcher, 0);
    }

    int findElement(TextElementMatcher matcher, int from) {
        int res = tryToFindElement(matcher, from);
        if (res == NOT_FOUND) {
            throw new IllegalArgumentException(
                    String.format("I could not find child '%s' from position %d. Elements: %s",
                            matcher, from, elements));
        } else {
            return res;
        }
    }

    int tryToFindElement(TextElementMatcher matcher, int from) {
        for (int i=from; i<elements.size(); i++) {
            TextElement element = elements.get(i);
            if (matcher.match(element)) {
                return i;
            }
        }
        return NOT_FOUND;
    }

    int findChild(Node child) {
        return findChild(child, 0);
    }

    int findChild(Node child, int from) {
        return findElement(TextElementMatchers.byNode(child), from);
    }

    int tryToFindChild(Node child) {
        return tryToFindChild(child, 0);
    }

    int tryToFindChild(Node child, int from) {
        return tryToFindElement(TextElementMatchers.byNode(child), from);
    }

    //
    // Removing single elements
    //

    void remove(TextElementMatcher matcher) {
        elements.removeIf(matcher::match);
    }

    public void remove(TextElementMatcher matcher, boolean potentiallyFollowingWhitespace) {
        int i=0;
        for (TextElement e : elements) {
            if (matcher.match(e)) {
                elements.remove(e);
                if (potentiallyFollowingWhitespace) {
                    if (i < elements.size()) {
                        if (elements.get(i).isWhiteSpace()) {
                            elements.remove(i);
                        }
                    } else {
                        throw new UnsupportedOperationException();
                    }
                }
                return;
            }
        }
        throw new IllegalArgumentException();
    }

    //
    // Removing sequences
    //

    void removeElement(int index) {
        elements.remove(index);
    }

    //
    // Replacing elements
    //

    void replace(TextElementMatcher position, TextElement newElement) {
        int index = findElement(position, 0);
        elements.remove(index);
        elements.add(index, newElement);
    }

    //
    // Other methods
    //

    /**
     * Generate the corresponding string.
     */
    String expand() {
        StringBuffer sb = new StringBuffer();

        elements.forEach(e -> sb.append(e.expand()));
        return sb.toString();
    }

    // Visible for testing
    int numberOfElements() {
        return elements.size();
    }

    // Visible for testing
    TextElement getTextElement(int index) {
        return elements.get(index);
    }

    // Visible for testing
    List<TextElement> getElements() {
        return elements;
    }

    @Override
    public String toString() {
        return "NodeText{" + elements + '}';
    }
}