/*
 * The JastAdd Extensible Java Compiler (http://jastadd.org) is covered
 * by the modified BSD License. You should have received a copy of the
 * modified BSD license with this compiler.
 * 
 * Copyright (c) 2005-2008, Torbjorn Ekman
 * All rights reserved.
 */

aspect LocalNum {
  inh lazy int VariableDeclaration.localNum();
  inh lazy int Stmt.localNum();
  inh lazy int ParameterDeclaration.localNum();

  eq Program.getChild(int index).localNum() = 0;

  syn lazy int MethodDecl.offsetBeforeParameters() = isStatic() ? 0 : 1;
  
  syn lazy int MethodDecl.offsetAfterParameters() {
    if(getNumParameter() == 0)
      return offsetBeforeParameters();
    return getParameter(getNumParameter()-1).localNum() + 
           getParameter(getNumParameter()-1).type().variableSize();
  }
  
  eq MethodDecl.getParameter(int index).localNum() {
    if(index == 0)
      return offsetBeforeParameters();
    return getParameter(index-1).localNum() + getParameter(index-1).type().variableSize();
  }

  eq InstanceInitializer.getBlock().localNum() = 1;

  inh lazy int ReturnStmt.resultSaveLocalNum();
  eq MethodDecl.getBlock().resultSaveLocalNum() = offsetAfterParameters();
  eq Program.getChild().resultSaveLocalNum() {
    throw new Error("Unsupported operation resultSaveLocalNum");
  }

  syn lazy int MethodDecl.resultOffset() = type().isVoid() ? 0 : type().variableSize();
  
  eq MethodDecl.getBlock().localNum() = offsetAfterParameters() + 
      resultOffset();

  syn lazy int ConstructorDecl.localNumOfFirstParameter() {
    int i = 1;
    if(hostType().needsEnclosing())
      i++;
    if(hostType().needsSuperEnclosing())
      i++;
    return i;
  }

  syn lazy int ConstructorDecl.offsetFirstEnclosingVariable() {
    int localIndex = localNumOfFirstParameter();
    Collection vars = hostType().enclosingVariables();
    if(vars.isEmpty())
      return localIndex;
    String name = "val$" + ((Variable)vars.iterator().next()).name();
    for(int i = 0; !getParameter(i).name().equals(name); i++)
      localIndex += getParameter(i).type().variableSize();
    return localIndex;
  }

  syn int ConstructorDecl.localIndexOfEnclosingVariable(Variable v) {
    int localIndex  = offsetFirstEnclosingVariable();
    Iterator iter = hostType().enclosingVariables().iterator();
    Variable varDecl = (Variable)iter.next();
    while(varDecl != v && iter.hasNext()) {
      localIndex += varDecl.type().variableSize();
      varDecl = (Variable)iter.next();
    }
    return localIndex;
  }

  eq ConstructorDecl.getParameter(int index).localNum() = index == 0 ?
    localNumOfFirstParameter() :
    getParameter(index-1).localNum() + getParameter(index-1).type().variableSize();

  eq ConstructorDecl.getBlock().localNum() = getNumParameter() == 0 ? 
    localNumOfFirstParameter() :
    getParameter(getNumParameter()-1).localNum() + getParameter(getNumParameter()-1).type().variableSize();

  eq ForStmt.getStmt().localNum() {
    if(getNumInitStmt() == 0)
      return localNum();
    if(getInitStmt(getNumInitStmt()-1) instanceof VariableDeclaration)
      return getInitStmt(getNumInitStmt()-1).localNum() + ((VariableDeclaration)getInitStmt(getNumInitStmt()-1)).type().variableSize();
    return getInitStmt(getNumInitStmt()-1).localNum();
  }
  
  eq ForStmt.getInitStmt(int index).localNum() {
    if(index == 0)
      return localNum();
    if(getInitStmt(index-1) instanceof VariableDeclaration)
      return getInitStmt(index-1).localNum() + ((VariableDeclaration)getInitStmt(index-1)).type().variableSize();
    return getInitStmt(index-1).localNum();
  }
  
  eq Block.getStmt(int index).localNum() {
    if(index == 0)
      return localNum();
    if(getStmt(index-1) instanceof VariableDeclaration)
      return getStmt(index-1).localNum() + ((VariableDeclaration)getStmt(index-1)).type().variableSize();
    return getStmt(index-1).localNum();
  }

  eq TryStmt.getFinally().localNum() = localNum() + 2;

  eq CatchClause.getBlock().localNum() = getParameter().localNum() + getParameter().type().variableSize();

  eq SynchronizedStmt.getBlock().localNum() = localNum() + 3;

  syn int TypeDecl.variableSize() = 0;
  eq ReferenceType.variableSize() = 1;
  eq PrimitiveType.variableSize() = 1;
  eq LongType.variableSize() = 2;
  eq DoubleType.variableSize() = 2;
  eq NullType.variableSize() = 1;
}