/***
 * ASM XML Adapter
 * Copyright (c) 2004-2011, Eugene Kuleshov
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.objectweb.asm.xml;

import java.util.HashMap;
import java.util.Map;

import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.Handle;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.TypePath;
import org.objectweb.asm.util.Printer;
import org.xml.sax.helpers.AttributesImpl;

/**
 * A {@link MethodVisitor} that generates SAX 2.0 events from the visited
 * method.
 * 
 * @see org.objectweb.asm.xml.SAXClassAdapter
 * @see org.objectweb.asm.xml.Processor
 * 
 * @author Eugene Kuleshov
 */
public final class SAXCodeAdapter extends MethodVisitor {

  static final String[] TYPES = { "top", "int", "float", "double", "long", "null", "uninitializedThis" };

  SAXAdapter sa;

  int access;

  private final Map<Label, String> labelNames;

  /**
   * Constructs a new {@link SAXCodeAdapter SAXCodeAdapter} object.
   * 
   * @param sa
   *          content handler that will be used to send SAX 2.0 events.
   */
  public SAXCodeAdapter(final SAXAdapter sa, final int access) {
    super(Opcodes.ASM6);
    this.sa = sa;
    this.access = access;
    this.labelNames = new HashMap<Label, String>();
  }

  @Override
  public void visitParameter(String name, int access) {
    AttributesImpl attrs = new AttributesImpl();
    if (name != null) {
      attrs.addAttribute("", "name", "name", "", name);
    }
    StringBuilder sb = new StringBuilder();
    SAXClassAdapter.appendAccess(access, sb);
    attrs.addAttribute("", "access", "access", "", sb.toString());
    sa.addElement("parameter", attrs);
  }

  @Override
  public final void visitCode() {
    if ((access & (Opcodes.ACC_ABSTRACT | Opcodes.ACC_INTERFACE | Opcodes.ACC_NATIVE)) == 0) {
      sa.addStart("code", new AttributesImpl());
    }
  }

  @Override
  public void visitFrame(final int type, final int nLocal, final Object[] local, final int nStack, final Object[] stack) {
    AttributesImpl attrs = new AttributesImpl();
    switch (type) {
    case Opcodes.F_NEW:
    case Opcodes.F_FULL:
      if (type == Opcodes.F_NEW) {
        attrs.addAttribute("", "type", "type", "", "NEW");
      } else {
        attrs.addAttribute("", "type", "type", "", "FULL");
      }
      sa.addStart("frame", attrs);
      appendFrameTypes(true, nLocal, local);
      appendFrameTypes(false, nStack, stack);
      break;
    case Opcodes.F_APPEND:
      attrs.addAttribute("", "type", "type", "", "APPEND");
      sa.addStart("frame", attrs);
      appendFrameTypes(true, nLocal, local);
      break;
    case Opcodes.F_CHOP:
      attrs.addAttribute("", "type", "type", "", "CHOP");
      attrs.addAttribute("", "count", "count", "", Integer.toString(nLocal));
      sa.addStart("frame", attrs);
      break;
    case Opcodes.F_SAME:
      attrs.addAttribute("", "type", "type", "", "SAME");
      sa.addStart("frame", attrs);
      break;
    case Opcodes.F_SAME1:
      attrs.addAttribute("", "type", "type", "", "SAME1");
      sa.addStart("frame", attrs);
      appendFrameTypes(false, 1, stack);
      break;
    }
    sa.addEnd("frame");
  }

  private void appendFrameTypes(final boolean local, final int n, final Object[] types) {
    for (int i = 0; i < n; ++i) {
      Object type = types[i];
      AttributesImpl attrs = new AttributesImpl();
      if (type instanceof String) {
        attrs.addAttribute("", "type", "type", "", (String) type);
      } else if (type instanceof Integer) {
        attrs.addAttribute("", "type", "type", "", TYPES[((Integer) type).intValue()]);
      } else {
        attrs.addAttribute("", "type", "type", "", "uninitialized");
        attrs.addAttribute("", "label", "label", "", getLabel((Label) type));
      }
      sa.addElement(local ? "local" : "stack", attrs);
    }
  }

  @Override
  public final void visitInsn(final int opcode) {
    sa.addElement(Printer.OPCODES[opcode], new AttributesImpl());
  }

  @Override
  public final void visitIntInsn(final int opcode, final int operand) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "value", "value", "", Integer.toString(operand));
    sa.addElement(Printer.OPCODES[opcode], attrs);
  }

  @Override
  public final void visitVarInsn(final int opcode, final int var) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "var", "var", "", Integer.toString(var));
    sa.addElement(Printer.OPCODES[opcode], attrs);
  }

  @Override
  public final void visitTypeInsn(final int opcode, final String type) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "desc", "desc", "", type);
    sa.addElement(Printer.OPCODES[opcode], attrs);
  }

  @Override
  public final void visitFieldInsn(final int opcode, final String owner, final String name, final String desc) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "owner", "owner", "", owner);
    attrs.addAttribute("", "name", "name", "", name);
    attrs.addAttribute("", "desc", "desc", "", desc);
    sa.addElement(Printer.OPCODES[opcode], attrs);
  }

  @Override
  public final void visitMethodInsn(final int opcode, final String owner, final String name, final String desc, final boolean itf) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "owner", "owner", "", owner);
    attrs.addAttribute("", "name", "name", "", name);
    attrs.addAttribute("", "desc", "desc", "", desc);
    attrs.addAttribute("", "itf", "itf", "", itf ? "true" : "false");
    sa.addElement(Printer.OPCODES[opcode], attrs);
  }

  @Override
  public void visitInvokeDynamicInsn(String name, String desc, Handle bsm, Object... bsmArgs) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "name", "name", "", name);
    attrs.addAttribute("", "desc", "desc", "", desc);
    attrs.addAttribute("", "bsm", "bsm", "", SAXClassAdapter.encode(bsm.toString()));
    sa.addStart("INVOKEDYNAMIC", attrs);
    for (int i = 0; i < bsmArgs.length; i++) {
      sa.addElement("bsmArg", getConstantAttribute(bsmArgs[i]));
    }
    sa.addEnd("INVOKEDYNAMIC");
  }

  @Override
  public final void visitJumpInsn(final int opcode, final Label label) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "label", "label", "", getLabel(label));
    sa.addElement(Printer.OPCODES[opcode], attrs);
  }

  @Override
  public final void visitLabel(final Label label) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "name", "name", "", getLabel(label));
    sa.addElement("Label", attrs);
  }

  @Override
  public final void visitLdcInsn(final Object cst) {
    sa.addElement(Printer.OPCODES[Opcodes.LDC], getConstantAttribute(cst));
  }

  private static AttributesImpl getConstantAttribute(final Object cst) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "cst", "cst", "", SAXClassAdapter.encode(cst.toString()));
    attrs.addAttribute("", "desc", "desc", "", Type.getDescriptor(cst.getClass()));
    return attrs;
  }

  @Override
  public final void visitIincInsn(final int var, final int increment) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "var", "var", "", Integer.toString(var));
    attrs.addAttribute("", "inc", "inc", "", Integer.toString(increment));
    sa.addElement(Printer.OPCODES[Opcodes.IINC], attrs);
  }

  @Override
  public final void visitTableSwitchInsn(final int min, final int max, final Label dflt, final Label... labels) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "min", "min", "", Integer.toString(min));
    attrs.addAttribute("", "max", "max", "", Integer.toString(max));
    attrs.addAttribute("", "dflt", "dflt", "", getLabel(dflt));
    String o = Printer.OPCODES[Opcodes.TABLESWITCH];
    sa.addStart(o, attrs);
    for (int i = 0; i < labels.length; i++) {
      AttributesImpl att2 = new AttributesImpl();
      att2.addAttribute("", "name", "name", "", getLabel(labels[i]));
      sa.addElement("label", att2);
    }
    sa.addEnd(o);
  }

  @Override
  public final void visitLookupSwitchInsn(final Label dflt, final int[] keys, final Label[] labels) {
    AttributesImpl att = new AttributesImpl();
    att.addAttribute("", "dflt", "dflt", "", getLabel(dflt));
    String o = Printer.OPCODES[Opcodes.LOOKUPSWITCH];
    sa.addStart(o, att);
    for (int i = 0; i < labels.length; i++) {
      AttributesImpl att2 = new AttributesImpl();
      att2.addAttribute("", "name", "name", "", getLabel(labels[i]));
      att2.addAttribute("", "key", "key", "", Integer.toString(keys[i]));
      sa.addElement("label", att2);
    }
    sa.addEnd(o);
  }

  @Override
  public final void visitMultiANewArrayInsn(final String desc, final int dims) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "desc", "desc", "", desc);
    attrs.addAttribute("", "dims", "dims", "", Integer.toString(dims));
    sa.addElement(Printer.OPCODES[Opcodes.MULTIANEWARRAY], attrs);
  }

  @Override
  public final void visitTryCatchBlock(final Label start, final Label end, final Label handler, final String type) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "start", "start", "", getLabel(start));
    attrs.addAttribute("", "end", "end", "", getLabel(end));
    attrs.addAttribute("", "handler", "handler", "", getLabel(handler));
    if (type != null) {
      attrs.addAttribute("", "type", "type", "", type);
    }
    sa.addElement("TryCatch", attrs);
  }

  @Override
  public final void visitMaxs(final int maxStack, final int maxLocals) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "maxStack", "maxStack", "", Integer.toString(maxStack));
    attrs.addAttribute("", "maxLocals", "maxLocals", "", Integer.toString(maxLocals));
    sa.addElement("Max", attrs);

    sa.addEnd("code");
  }

  @Override
  public void visitLocalVariable(final String name, final String desc, final String signature, final Label start, final Label end, final int index) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "name", "name", "", name);
    attrs.addAttribute("", "desc", "desc", "", desc);
    if (signature != null) {
      attrs.addAttribute("", "signature", "signature", "", SAXClassAdapter.encode(signature));
    }
    attrs.addAttribute("", "start", "start", "", getLabel(start));
    attrs.addAttribute("", "end", "end", "", getLabel(end));
    attrs.addAttribute("", "var", "var", "", Integer.toString(index));
    sa.addElement("LocalVar", attrs);
  }

  @Override
  public final void visitLineNumber(final int line, final Label start) {
    AttributesImpl attrs = new AttributesImpl();
    attrs.addAttribute("", "line", "line", "", Integer.toString(line));
    attrs.addAttribute("", "start", "start", "", getLabel(start));
    sa.addElement("LineNumber", attrs);
  }

  @Override
  public AnnotationVisitor visitAnnotationDefault() {
    return new SAXAnnotationAdapter(sa, "annotationDefault", 0, null, null);
  }

  @Override
  public AnnotationVisitor visitAnnotation(final String desc, final boolean visible) {
    return new SAXAnnotationAdapter(sa, "annotation", visible ? 1 : -1, null, desc);
  }

  @Override
  public AnnotationVisitor visitTypeAnnotation(int typeRef, TypePath typePath, String desc, boolean visible) {
    return new SAXAnnotationAdapter(sa, "typeAnnotation", visible ? 1 : -1, null, desc, typeRef, typePath);
  }

  @Override
  public AnnotationVisitor visitParameterAnnotation(final int parameter, final String desc, final boolean visible) {
    return new SAXAnnotationAdapter(sa, "parameterAnnotation", visible ? 1 : -1, parameter, desc);
  }

  @Override
  public AnnotationVisitor visitInsnAnnotation(int typeRef, TypePath typePath, String desc, boolean visible) {
    return new SAXAnnotationAdapter(sa, "insnAnnotation", visible ? 1 : -1, null, desc, typeRef, typePath);
  }

  @Override
  public AnnotationVisitor visitTryCatchAnnotation(int typeRef, TypePath typePath, String desc, boolean visible) {
    return new SAXAnnotationAdapter(sa, "tryCatchAnnotation", visible ? 1 : -1, null, desc, typeRef, typePath);
  }

  @Override
  public AnnotationVisitor visitLocalVariableAnnotation(int typeRef, TypePath typePath, Label[] start, Label[] end, int[] index, String desc,
      boolean visible) {
    String[] s = new String[start.length];
    String[] e = new String[end.length];
    for (int i = 0; i < s.length; ++i) {
      s[i] = getLabel(start[i]);
    }
    for (int i = 0; i < e.length; ++i) {
      e[i] = getLabel(end[i]);
    }
    return new SAXAnnotationAdapter(sa, "localVariableAnnotation", visible ? 1 : -1, null, desc, typeRef, typePath, s, e, index);
  }

  @Override
  public void visitEnd() {
    sa.addEnd("method");
  }

  private final String getLabel(final Label label) {
    String name = labelNames.get(label);
    if (name == null) {
      name = Integer.toString(labelNames.size());
      labelNames.put(label, name);
    }
    return name;
  }

}
