package plparser;

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.StringReader;
import java.util.Scanner;
import java.util.regex.Pattern;

/**
 * delimiter に何を設定しても動いてくれない。
 * */

public class PropertyListStreamScanner<T> extends PLScannerImpl<T> implements
		PLScanner<T> {

	private Scanner scan;
	
	public PropertyListStreamScanner(
			PLScanner<T> s,
			Dictionary<T> dict, Token<T> nullToken) {
		super(s,dict,nullToken);
	}

	public void init() {
		String pattern = ".";
		scan.useDelimiter(pattern);
	}

	// Pattern must contain exact 1 group
	private static Pattern tokenPat = Pattern.compile(
			"([={}(),;])"
	);
	private static Pattern namePat  = Pattern.compile("([_a-zA-Z][\\@\\w]*)");
	private static final Pattern numPat  = Pattern.compile("([0-9]+)");
	private static final Pattern stringPat1  = Pattern.compile("\\\"([^\"]*)\\\"");
	private static final Pattern stringPat  = Pattern.compile("\\'([^\\']*)\\'");
	private static final Pattern stringPat1cont  = Pattern.compile("\\\"([^\"]*)$");
	private static final Pattern stringPatCont  = Pattern.compile("\\'([^\\']*)$");
	private static final Pattern stringPat1End  = Pattern.compile("([^\"]*)\\\"");
	private static final Pattern stringPatEnd  = Pattern.compile("([^\\']*)\'");
	private static final Pattern commentPat  = Pattern.compile("(//.*)");
	private static final Pattern commentPat1  = Pattern.compile("(/\\*)");
	private static final Pattern commentPat1End  = Pattern.compile("(.*\\*/)");
	private static final Pattern errorPat = Pattern.compile("([^\\s])");
	private static final Pattern anyPat = Pattern.compile("(.)");
	
	@Override
	public Token<T> nextToken() {
		String s;
		nextToken = nullToken;
		while(hasRemaining()) {
			if ((s=scan.next(tokenPat))!=null) {
				Token<T> t;
				if ((t = dict.get(s))==null) {
					dict.put(s, t = new Token<T>(s,TokenID.Any));
				}
				return nextToken = t;
			} else if ((s=scan.next(stringPatCont))!=null) {
				// non terminated string
				String s1;
				while((s1=scan.next(stringPatEnd))==null) {
					s += scan.nextLine();
					lineno++;
				}
				s += s1;
				Token<T> t;
				if ((t = dict.get(s))==null) {
					dict.put(s, t = new Token<T>(s,TokenID.VARIABLE));
				}
				return nextToken = t;
			} else if ((s=scan.next(stringPat1cont))!=null) {
				// non terminated string
				String s1;
				while((s1=scan.next(stringPat1End))==null) {
					s += scan.nextLine();
					lineno++;
				}
				s += s1;
				Token<T> t;
				if ((t = dict.get(s))==null) {
					dict.put(s, t = new Token<T>(s,TokenID.VARIABLE));
				}
				return nextToken = t;
			} else if ((s=scan.next(stringPat))!=null||(s=scan.next(stringPat1))!=null||(s=scan.next(namePat))!=null) {
				Token<T> t;
				if ((t = dict.get(s))==null) {
					dict.put(s, t = new Token<T>(s,TokenID.VARIABLE));
				}
				if (t.type!=TokenID.VARIABLE) {
					t = new Token<T>(s,TokenID.VARIABLE);
				}
				return nextToken = t;
			} else if ((s=scan.next(numPat))!=null) {
				return nextToken = new Token<T>(s,TokenID.NUMBER);
			} else if ((s=scan.next(commentPat))!=null) {
				scan.nextLine();
				continue;
			} else if ((s=scan.next(commentPat1))!=null) {
				while(scan.next(commentPat1End)==null) {
					scan.nextLine();
					lineno++;
				}
				continue;
			} else if ((s=scan.next(errorPat))!=null) {
				error("Don't understand '"+s+"'");
				continue;
			} else if ((s=scan.next(anyPat))!=null) {
				// skip space
				continue;
			} else {
				lineno++;
			}
		}
		return nextToken;
	}


	@Override
	public boolean hasRemaining() {
		return scan.hasNext(anyPat);
	}

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

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

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

	@Override
	public PLScanner<T> set(String exp) {
		Reader reader = new StringReader(exp);
		scan = new Scanner(reader);
		return this;
	}

	@Override
	public PLScanner<T> setFile(String file)
			throws FileNotFoundException {
		Reader reader = new FileReader(file);
		scan = new Scanner(reader);
		return this;
	}

	@Override
	public PLScanner<T> set(InputStreamReader reader) {
		scan = new Scanner(reader);
		return this;
	}



}