package plparser;

import java.io.FileNotFoundException;
import java.io.InputStream;
import java.nio.CharBuffer;

public class PropertyListCharTokenizer<T> extends PropertyListScanner<T>
		implements PLScanner<T> {

	public PropertyListCharTokenizer(Dictionary<T> dict) {
		super(dict);
	}

	public PropertyListCharTokenizer(
			PLScanner<T>s,
			Dictionary<T> dict, Token<T> nullToken) {
		super(dict);
		this.nullToken = nullToken;
		this.prev = null;
	}

	public char ch;
	
	@Override
	public Token<T> nextToken() {
		nextToken = nullToken;
		if (cb==null) return nextToken;
		if (!hasRemaining()) return nextToken;
		while(Character.isSpaceChar(ch)) {
			if (!hasRemaining()) return nextToken;
			ch = nextChar(); 
		}
		CharBuffer w = CharBuffer.allocate(BufferSize);
		if (Character.isJavaIdentifierStart(ch)) {
			w.put(ch);
			while(hasRemaining()&&Character.isJavaIdentifierPart((ch=nextChar()))) {
				w.put(ch);
			}
			return lookupDict(w);
		} else if (Character.isDigit(ch)||ch=='-'||ch=='+') {
			w.put(ch);
			while(hasRemaining()&&Character.isDigit((ch=nextChar()))) {
				w.put(ch);
			}
			return nextToken = new Token<T>(w.toString(),TokenID.NUMBER);
		} else if (ch=='/') {
			w.put(ch); 	
			if (!hasRemaining()) return new Token<T>(w.toString(),TokenID.Any);
			ch = nextChar();
			if (ch=='/') {
				while(hasRemaining() && (ch=nextChar())!='\n');
				if (!hasRemaining())return nullToken;
				ch = nextChar();
				return nextToken();
			}
			if (ch=='*') {
				while(hasRemaining() && !((ch=nextChar())=='*'&&(ch=nextChar())=='/'));
				if (!hasRemaining())return nullToken;
				ch = nextChar();
				return nextToken();
			}
			return new Token<T>(w.toString(),TokenID.Any);
		} else if (ch=='\'') {
			while(hasRemaining() && (ch=nextChar())!='\'') w.put(ch);
			if (!hasRemaining())return nullToken; // non terminate string
			ch = nextChar();
			return lookupDict(w);
		} else if (ch=='"') {
			while(hasRemaining() && (ch=nextChar())!='"') w.put(ch);
			if (!hasRemaining())return nullToken; // non terminate string
			ch = nextChar();
			return lookupDict(w);
		} else {
			nextToken = lookupDict(w);
			if (!hasRemaining())return nextToken; 
			ch = nextChar();
			return nextToken;
		}
	}

	private Token<T> lookupDict(CharBuffer w) {
		Token<T> t;
		String s = w.toString();
		if ((t = dict.get(s))==null) {
			dict.put(s, t = new Token<T>(s,TokenID.Any));
		}
		return nextToken = t;
	}

	private char nextChar() {
		if (!cb.hasRemaining()) extendInput();
		char ch = cb.get();
		return ch;
	}


	@Override
	public PLScanner<T> pushScannerFile(InputStream newfile, String prompt) {
		return new PropertyListCharTokenizer<T>(this,dict,nullToken).setFile(newfile,prompt);
	}

	@Override
	public PLScanner<T> pushScanner(String exp) {
		return new PropertyListCharTokenizer<T>(this,dict,nullToken).set(exp);
	}

	@Override
	public PLScanner<T> pushScannerFile(String newfile)
			throws FileNotFoundException {
		return new PropertyListCharTokenizer<T>(this,dict,nullToken).setFile(newfile);
	}
}