/*
 [The "BSD license"]
 Copyright (c) 2011 Terence Parr
 All rights reserved.

 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions
 are met:

 1. Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.
 2. 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.
 3. The name of the author may not be used to endorse or promote products
    derived from this software without specific prior written permission.

 THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 org.antlr.v4.runtime;

import java.io.Serializable;

public class CommonToken implements WritableToken, Serializable {
	protected int type;
	protected int line;
	protected int charPositionInLine = -1; // set to invalid position
	protected int channel=DEFAULT_CHANNEL;
	protected TokenSource source;
	// TODO: rm protected transient CharStream input;

	/** We need to be able to change the text once in a while.  If
	 *  this is non-null, then getText should return this.  Note that
	 *  start/stop are not affected by changing this.
	  */
	// TODO: can store these in map in token stream rather than as field here
	protected String text;

	/** What token number is this from 0..n-1 tokens; < 0 implies invalid index */
	protected int index = -1;

	/** The char position into the input buffer where this token starts */
	protected int start;

	/** The char position into the input buffer where this token stops */
	protected int stop;

	public CommonToken(int type) {
		this.type = type;
	}

	public CommonToken(TokenSource source, int type, int channel, int start, int stop) {
		this.source = source;
		this.type = type;
		this.channel = channel;
		this.start = start;
		this.stop = stop;
        this.line = source.getLine();
        this.charPositionInLine = source.getCharPositionInLine();
	}

	public CommonToken(int type, String text) {
		this.type = type;
		this.channel = DEFAULT_CHANNEL;
		this.text = text;
	}

	public CommonToken(Token oldToken) {
		text = oldToken.getText();
		type = oldToken.getType();
		line = oldToken.getLine();
		index = oldToken.getTokenIndex();
		charPositionInLine = oldToken.getCharPositionInLine();
		channel = oldToken.getChannel();
        source = oldToken.getTokenSource();
		if ( oldToken instanceof CommonToken ) {
			start = ((CommonToken)oldToken).start;
			stop = ((CommonToken)oldToken).stop;
		}
	}

	@Override
	public int getType() {
		return type;
	}

	@Override
	public void setLine(int line) {
		this.line = line;
	}

	@Override
	public String getText() {
		if ( text!=null ) {
			return text;
		}
		TokenSource tokens = getTokenSource();
		if ( tokens==null ) return null;
		CharStream input = tokens.getInputStream();
		if ( input==null ) return null;
		int n = input.size();
		if ( start<n && stop<n) {
			return input.substring(start,stop);
		}
		else {
			return "<EOF>";
		}
	}

	/** Override the text for this token.  getText() will return this text
	 *  rather than pulling from the buffer.  Note that this does not mean
	 *  that start/stop indexes are not valid.  It means that that input
	 *  was converted to a new string in the token object.
	 */
	@Override
	public void setText(String text) {
		this.text = text;
	}

	@Override
	public int getLine() {
		return line;
	}

	@Override
	public int getCharPositionInLine() {
		return charPositionInLine;
	}

	@Override
	public void setCharPositionInLine(int charPositionInLine) {
		this.charPositionInLine = charPositionInLine;
	}

	@Override
	public int getChannel() {
		return channel;
	}

	@Override
	public void setChannel(int channel) {
		this.channel = channel;
	}

	@Override
	public void setType(int type) {
		this.type = type;
	}

	@Override
	public int getStartIndex() {
		return start;
	}

	public void setStartIndex(int start) {
		this.start = start;
	}

	@Override
	public int getStopIndex() {
		return stop;
	}

	public void setStopIndex(int stop) {
		this.stop = stop;
	}

	@Override
	public int getTokenIndex() {
		return index;
	}

	@Override
	public void setTokenIndex(int index) {
		this.index = index;
	}

	@Override
	public TokenSource getTokenSource() {
		return source;
	}

	public CharStream getInputStream() {
		return source.getInputStream();
	}

	public String toString() {
		String channelStr = "";
		if ( channel>0 ) {
			channelStr=",channel="+channel;
		}
		String txt = getText();
		if ( txt!=null ) {
			txt = txt.replaceAll("\n","\\\\n");
			txt = txt.replaceAll("\r","\\\\r");
			txt = txt.replaceAll("\t","\\\\t");
		}
		else {
			txt = "<no text>";
		}
		return "[@"+getTokenIndex()+","+start+":"+stop+"='"+txt+"',<"+type+">"+channelStr+","+line+":"+getCharPositionInLine()+"]";
	}
}

@@ -2632,24 +2632,43 @@
 = stop;%0A
-        
+%09%09if (source != null) %7B%0A%09%09%09
 this.lin
@@ -2689,24 +2689,19 @@
 Line();%0A
-        
+%09%09%09
 this.cha
@@ -2746,24 +2746,28 @@
 onInLine();%0A
+%09%09%7D%0A
 %09%7D%0A%0A%09public 
@@ -5113,24 +5113,41 @@
 ) %7B%0A%09%09return
+ source != null ?
  source.getI
@@ -5158,16 +5158,23 @@
 Stream()
+ : null
 ;%0A%09%7D%0A%0A%09p

Fix NPE in CommonToken when TokenSource is not available