// gensubgraph.beh -- generate code for SubgraphVisitor.
// $Id: gensubgraphvis.beh,v 1.3 2000/10/23 19:32:00 dougo Exp $

Program {
  /** Add a "SubgraphVisitor" class to the set of class definitions.
      Don't call this until after buildClassDefTable()! */
  void addSubgraphVisitor(String name) {{
    addClassDef(ClassDef.parse("notparsed visitor " + name + " = "
			       + "<is_equal> boolean init "
			       + Text.begin + " true " + Text.end + "."));
  }}
  /** Generate the behavior file for SubgraphVisitor. */
  void generateSubgraphVisitor(String name, File file) = allParts {
    before Program {{
      host.openOutputFile(file);
      Program.out.println(
 "// This file is automatically generated by DemeterJ.\n"
+"\n"
+ name + " {\n"
+"  " + Text.begin + "\n"
+"    private java.util.Stack history = new java.util.Stack();\n"
+"    public " + name + "(Object obj) {\n"
+"      history.push(obj);\n"
+"    }\n"
+"  " + Text.end + "\n"
      );
    }}

    {{ ClassName classname; String body; }}
    before ClassDef {{
      classname = host.get_classname();
      body =
	"    Object obj = history.peek();\n" +
	"    is_equal = is_equal && obj.getClass().equals(host.getClass());\n"+
	"    if(!is_equal) return;\n";
    }}

    {{ int tempcount=0; }}
    before Part {{
      // Don't compare final or static members.
      if (host.isFinal() || host.isStatic() /* || host.isDerived() */) return;
      PartName partname = host.get_partname();
      ClassName dest = host.get_classname();
      if (Program.prog.definesClass(dest)) {
	String part_body =
	  "    if (is_equal) {\n" +
	  "      " + classname + " obj = (" + classname + ") history.peek();\n" +
	  "      Object temp" + ++tempcount + " = obj.get_" + partname + "();\n" +
	  "      if(temp" + tempcount + "==null) { is_equal = false; return; }\n" +
	  "      history.push(temp" + tempcount + ");\n" +
	  "    }\n";
	Program.out.println(
	  host.makeBefore(classname, part_body) + "\n"
	+ host.makeAfter(classname, "    if (is_equal) history.pop();\n")
	+ "\n");
      } else {
	/*
	body += "\n      && host.get_" + partname + "()";
	String rest = "((" + classname + ") obj).get_" + partname + "()";
	if (dest.isBuiltinType()) {
	  body += " == " + rest;
	} else {
	  body += ".equals(" + rest + ")";
	}
	*/
	String rest = "((" + classname + ") obj).get_" + partname + "()";
	if(dest.isBuiltinType()) {
	  body +=
	    "    is_equal = is_equal && host.get_" + partname + "() == " + rest + ";\n";
	} else {
	  body +=
            "    Object temp" + ++tempcount + " = host.get_" + partname + "();\n" +
	    "    Object temp" + ++tempcount + " = " + rest + ";\n" +
	    "    if(temp" + (tempcount-1) + " == null && temp" + tempcount + " == null) {}\n" +
	    "    else if(temp" + (tempcount-1) + " == null ||\n" +
            "            temp" +  tempcount    + " == null ||\n" +
	    "            !temp" + (tempcount-1) + ".equals(temp" + tempcount + ")) { is_equal = false; return; }\n";
	}
      }
    }}

    after ClassDef {{
      Program.out.println(classname.makeBefore(body) + "\n");
    }}

    after Program {{
      Program.out.println(
	"  return boolean " + Text.begin + " is_equal " + Text.end + "\n}");
      host.closeOutputFile();
    }}
  }
}