/*
 * Created on Oct 14, 2005
 *
 * TODO To change the template for this generated file go to
 * Window - Preferences - Java - Code Style - Code Templates
 */
package fr.lifl.stc.stan.classAnnoter;

import java.io.IOException;

import org.apache.bcel.classfile.Attribute;
import org.apache.bcel.classfile.ExactLinkAttribute;
import org.apache.bcel.classfile.GlobalLinkAttribute;
import org.apache.bcel.classfile.JavaClass;
import org.apache.bcel.classfile.Method;
import org.apache.bcel.generic.ConstantPoolGen;
import fr.lifl.stc.stan.analyser.Config;
import fr.lifl.stc.stan.samples.flow.FlowAnnotation;
import fr.lifl.stc.stan.samples.flow.FlowPartialSignature;
import fr.lifl.stc.stan.samples.flow.FlowPartialSignatureData;
import fr.lifl.stc.stan.signature.Signature;
import fr.lifl.stc.stan.signature.SignatureDictionary;

/**
 * @author dorina
 *
 * Annotates a <code>.class</code> file with its exact and global signatures.
 */
public class LinkMapClassAnnoter {

	private JavaClass cl;

	private String classfile = null;

	private SignatureDictionary dict = null;

	private ConstantPoolGen cpg = null;

	private int link_index;
	private int global_link_index;

	private String output = null;

	public LinkMapClassAnnoter(JavaClass cl, SignatureDictionary dict) {
		this.cl = cl;
		this.classfile = cl.getFileName();
		//cl.
		this.output = Config.annotationRep()+cl.getClassName().replace('.','/')+".class";
		//+ this.classfile;
		this.dict = dict;
		this.prepareConstantPool();

	}

	private void prepareConstantPool() {
		cpg = new ConstantPoolGen(cl.getConstantPool());

		link_index = cpg.addUtf8("LinkMap");
		global_link_index = cpg.addUtf8("GlobalLinkMap");

		cl.setConstantPool(cpg.getFinalConstantPool());
	}

	public void annotateClass() throws IOException {
		Method[] methods = cl.getMethods();
		for(int i = 0; i < methods.length; i++) {
			//if(methods[i].isAbstract() || methods[i].isNative())
			//	continue;

			//Printer.println(SignatureDictionary.key(cl,methods[i]));
			Signature sign = dict.findExactSignature(SignatureDictionary.key(cl,methods[i]));

			if (sign == null) {
				System.err.println("Unknown method in " + cl.getClassName() + ": " + methods[i]);
				//continue;
			}
			else
				annotateExactLink (methods[i], sign);

			sign = dict.findGlobalSignature(SignatureDictionary.key(cl,methods[i]));
			if (sign == null) {
				System.err.println("Unknown method in " + cl.getClassName() + ": " + methods[i]);
				//continue;
			}
			else {
				annotateGlobalLink (methods[i], sign);
			}

		}

		String newname = (output == null)?classfile:output;
		//Printer.println("dump to "+newname);
		System.out.println("dump to "+newname);
		cl.dump(newname);
	}

	/**
	 *
	 * @param cl
	 * @param meth
	 * @param sign
	 */
	private void annotateExactLink(Method meth, Signature sign) {
		FlowPartialSignature link = (FlowPartialSignature) sign
		.getPartialSignature(FlowAnnotation.class.getName());

		//System.out.println("annotate sign = "+sign);

		if (link == null) {
			//System.err.println("Unsigned exact Link method in " + cl.getClassName()+ ": " + meth);
			return;
		}

		//short[] offsets = ((FlowPartialSignatureData)esc.getComponent()).getData();
		byte[] byteStream = ((FlowPartialSignatureData) link.getComponent())
		.getDataAsBytes();
		if (byteStream == null) {
			//Printer.println("No links in " + meth);
			return;
		}

		Attribute[] orig = null;
		orig = meth.getAttributes();

		if (byteStream.length > 0) {

			ExactLinkAttribute linkAttr = new ExactLinkAttribute(link_index,
					byteStream.length, byteStream, cl.getConstantPool());

			int j = 0;
			while (j < orig.length) {
				if (orig[j] instanceof ExactLinkAttribute)
					break;
				j++;
			}
			if (j < orig.length) {
				orig[j] = linkAttr;
					meth.setAttributes(orig);
			} else {
				Attribute[] new_attr = new Attribute[orig.length + 1];
				new_attr[0] = linkAttr;
				System.arraycopy(orig, 0, new_attr, 1, orig.length);
				meth.setAttributes(new_attr);
			}
		} else {
			//maybe suppress the attribute
			int j = 0;
			while (j < orig.length) {
				if (orig[j] instanceof ExactLinkAttribute) {
					break;
				}
				j++;
			}
			if (j < orig.length) {
				Attribute[] new_attr = new Attribute[orig.length - 1];
				if (j > 0)
					System.arraycopy(orig, 0, new_attr, 0, j);
				if (j < orig.length - 1)
					System.arraycopy(orig, j + 1, new_attr, j, orig.length - j
							- 1);
					meth.setAttributes(new_attr);
			}
		}
	}


	/**
	 *
	 * @param cl
	 * @param meth
	 * @param sign
	 */
	private void annotateGlobalLink(Method meth, Signature sign) {
		FlowPartialSignature link = (FlowPartialSignature) sign
		.getPartialSignature(FlowAnnotation.class.getName());

		if (link == null) {
			//System.err.println("Unsigned global Link method in " + cl.getClassName()+ ": " + meth);
			return;
		}

		//short[] offsets = ((FlowPartialSignatureData)esc.getComponent()).getData();
		byte[] byteStream = ((FlowPartialSignatureData) link.getComponent())
		.getDataAsBytes();
		if (byteStream == null) {
			//Printer.println("No links in " + meth);
			return;
		}

		Attribute[] orig = null;
//		if (meth.getCode() != null)
//			orig = meth.getCode().getAttributes();
//		else
			orig = meth.getAttributes();

		if (byteStream.length > 0) {

			GlobalLinkAttribute linkAttr = new GlobalLinkAttribute(global_link_index,
					byteStream.length, byteStream, cl.getConstantPool());
//			LinkAttribute ea = new LinkAttribute(link_index,2 * offsets.length, offsets, cl.getConstantPool());

			int j = 0;
			while (j < orig.length) {
				if (orig[j] instanceof GlobalLinkAttribute)
					break;
				j++;
			}
			if (j < orig.length) {
				orig[j] = linkAttr;
//				if (meth.getCode() != null)
//					meth.getCode().setAttributes(orig);
//				else
					meth.setAttributes(orig);
			} else {
				Attribute[] new_attr = new Attribute[orig.length + 1];
				new_attr[0] = linkAttr;
				System.arraycopy(orig, 0, new_attr, 1, orig.length);
//				if (meth.getCode() != null)
//					meth.getCode().setAttributes(new_attr);
//				else
					meth.setAttributes(new_attr);
			}
		} else {
			//maybe suppress the attribute
			int j = 0;
			while (j < orig.length) {
				if (orig[j] instanceof GlobalLinkAttribute) {
					break;
				}
				j++;
			}
			if (j < orig.length) {
				Attribute[] new_attr = new Attribute[orig.length - 1];
				if (j > 0)
					System.arraycopy(orig, 0, new_attr, 0, j);
				if (j < orig.length - 1)
					System.arraycopy(orig, j + 1, new_attr, j, orig.length - j
							- 1);
//				if (meth.getCode() != null)
//					meth.getCode().setAttributes(new_attr);
//				else
					meth.setAttributes(new_attr);
			}
		}
	}
}