package aQute.lib.osgi;

import java.io.*;
import java.util.zip.*;

public class EmbeddedResource implements Resource {
	byte	data[];
	long 	lastModified;
	String	extra;

	public EmbeddedResource(byte data[], long lastModified) {
		this.data = data;
		this.lastModified = lastModified;
	}

	public InputStream openInputStream() throws FileNotFoundException {
		return new ByteArrayInputStream(data);
	}

	public void write(OutputStream out) throws IOException {
		out.write(data);
	}

	public String toString() {
		return ":" + data.length + ":";
	}

	public static void build(Jar jar, InputStream in, long lastModified) throws IOException {
		ZipInputStream jin = new ZipInputStream(in);
		ZipEntry entry = jin.getNextEntry();
		while (entry != null) {
			if (!entry.isDirectory()) {
				byte data[] = collect(jin);
				jar.putResource(entry.getName(), new EmbeddedResource(data, lastModified), true);
			}
			entry = jin.getNextEntry();
		}
		jin.close();
	}

	/**
	 * Convenience method to turn an inputstream into a byte array. The method
	 * uses a recursive algorithm to minimize memory usage.
	 * 
	 * @param in stream with data
	 * @param offset where we are in the stream
	 * @returns byte array filled with data
	 */
    static byte[] collect(InputStream in) throws IOException {
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        copy(in,out);
        return out.toByteArray();
    }

    static void copy(InputStream in, OutputStream out) throws IOException {
        int available = in.available();
        if ( available <= 10000)
            available = 64000;
        byte [] buffer = new byte[available];
        int size;
        while ( (size=in.read(buffer))>0)
            out.write(buffer,0,size);
    }

	public long lastModified() {
		return lastModified;
	}

	public static void build(Jar sub, Resource resource) throws Exception {
			InputStream in = resource.openInputStream();
			build(sub,in, resource.lastModified());
			in.close();
	}

	public String getExtra() {
		return extra;
	}

	public void setExtra(String extra) {
		this.extra = extra;
	}

	public long size() {
	    return data.length;
	}
}