package ch.werner_randelshofer.activation;

/*
Copyright (C) 1999-99 Werner Randelshofer
werner.randelshofer@mythen.ch
http://www.mythen.ch/w.randelshofer/
    
Permission to use this release of MultiCTD is hereby
granted without fee provided that the complete copyright
notice and this permission notice appear in all copies
and in supporting documentation.
*/

import java.io.*;
import java.net.*;
import ch.werner_randelshofer.iff.*;
import java.util.Vector;
import java.util.Enumeration;

/**
This content type detector serves as a
container for a collection of content type detectors.

@author	Werner Randelshofer, Staldenmattweg 2, CH-6405 Immensee, Switzerland.
@version	1998-06-12	Created.
*/
public class MultiCTD
implements ContentTypeDetector
	{
	private Vector detectors_ = new Vector();
	private int minimalLength_;
	
	public void add(ContentTypeDetector detector)
		{
		minimalLength_ = Math.max(minimalLength_,detector.getMinimalDeterminableDataLength());
		detectors_.addElement(detector);
		}
	/**
	Return the number of bytes needed to
	determine the content type.
	*/ 
	public int getMinimalDeterminableDataLength()
		{
		return minimalLength_;
		}

	/**
	Return the base MIME Type of this data. This method is
	expected to ALWAYS return a valid (non-null) MIME Type.
	We suggest that if the DataTypeDetector implementation cannot 
	determine the type of the data, it use the convention of
	returning "application/octet-stream".

	@param	the first few bytes of the data file.
	@return MIME Type
	*/
	public String getContentType(byte[] dataSnippet)
		{
		Enumeration e = detectors_.elements();
		String contentType = ContentTypeDetector.CONTENT_TYPE_UNKNOWN;
		while (e.hasMoreElements() && contentType.equals(ContentTypeDetector.CONTENT_TYPE_UNKNOWN))
			{
			contentType = 
				((ContentTypeDetector)e.nextElement()).getContentType(dataSnippet);
			}
		return contentType;
		}
	}