package XAspectLanguage;
import java.util.*;
import java.util.jar.JarFile;
import java.io.*;
import edu.neu.ccs.demeter.aplib.*;
import edu.neu.ccs.demeter.dj.ClassGraph;
import edu.neu.ccs.demeter.*;
public class SemanticChecker {
  public SemanticChecker() {
    super();
  }
  public static SemanticChecker parse(java.io.Reader in) throws ParseException { return new Parser(in)._SemanticChecker(); }
  public static SemanticChecker parse(java.io.InputStream in) throws ParseException { return new Parser(in)._SemanticChecker(); }
  public static SemanticChecker parse(String s) {
    try { return parse(new java.io.StringReader(s)); }
    catch (ParseException e) {
      throw new RuntimeException(e.toString());
    }
  }

    // the runtime class graph
    static ClassGraph runtimeCg;
    // the class graph defined by the input class dictionary
    static edu.neu.ccs.demeter.aplib.cd.ClassGraph inputCg;
    // a pointer to the traversal XAspects component
    SelectorL ta;
    // list containing error messages
    List errors;
  
  public void generate(ClassDictionaryL cda, SelectorL travA) {
    // create the runtime class graph
    runtimeCg = new ClassGraph(true, false);
  	manuallyCreateClassGraph2();

    // create the class graph for the input class dictionary
    inputCg = ClassGraph.fromString(cda.get_classdict().get_text().toString());
    inputCg.normalize();

    // assign the pointer to the provided traversal aspect component
    ta = travA;

    errors = new LinkedList();
  }
  
  public List check() {
    // make some Traversal XAspects specific checks
    // i.e., make sure that "nodes" and regular expression declarations
    // utilize other declarations that are defined
    check_trav_nodesAndRegExp();

    // check in all places for undefined classes
    // i.e., check used classes in class dictionary, strategy expressions,
    // and class list declarations
    checkForUndefinedClasses();

    // verify that strategies represent legal paths
    checkTraversalPaths();

    return errors;
  }
  private void check_trav_nodesAndRegExp() {
    // check that all used Strategy names in "nodes" node set decls are defined
    List usedNames = runtimeCg.gather(ta, "from XAspectLanguage.SelectorL via XAspectLanguage.GraphNodes to" + Main.FIdent);
    List defNames = runtimeCg.gather(ta, "from XAspectLanguage.SelectorL via XAspectLanguage.StrategyDef via XAspectLanguage.StrategyName to" + Main.FIdent);
    subset_test(usedNames, defNames);    

    // check that regular expressions reference defined node sets
    List defNodeSetDecls = runtimeCg.gather(ta, "from XAspectLanguage.SelectorL bypassing XAspectLanguage.NodeSubsetExpression via XAspectLanguage.NodeSubsetName to" + Main.FIdent);
    List usedNodeSetDecls = runtimeCg.gather(ta, "from XAspectLanguage.SelectorL via XAspectLanguage.NodeSubsetExpression via XAspectLanguage.NodeSubsetName to" + Main.FIdent);
    subset_test(usedNodeSetDecls, defNodeSetDecls);
  }
  private void checkForUndefinedClasses() {
    // get a list of all used classes in input cd, and make sure each used class
    // is defined by the cd
    java.util.Collection c = inputCg.getNodes();
    checkDefinesClass(c.iterator());

    // NOTE: Commented out this check, the Traversal.compute(...) check takes care of this
    // check that all classes used in strategy expressions are defined
    //List usedClassNames = runtimeCg.gather(ta, "from SelectorL via StrategyExpression via ClassName to" + Main.FIdent);
    //checkDefinesClass(usedClassNames.iterator());

    // check classes are all defined in class list node sets
    List usedClasses = runtimeCg.gather(ta, "from XAspectLanguage.SelectorL via XAspectLanguage.ClassNameSet to" + Main.FIdent);
    checkDefinesClass(usedClasses.iterator());
  }
  private void subset_test(List used, List defined) {
    ListIterator usedIterator = used.listIterator();
    while (usedIterator.hasNext()) {
      Ident next = (Ident) usedIterator.next();
      if (!defined.contains(next)) {
        //System.out.println(next.toString() + " undefined.");
        errors.add(new String(next.toString() + " undefined."));
      }
    }
  }
  private void checkTraversalPaths() {
      try {
        // gather a list of declared strategy expressions
        List test = runtimeCg.gather(ta, "from XAspectLanguage.SelectorL to XAspectLanguage.Strategy");
        // for each strategy, try to compute a traversal given the input cd
        for (int i = 0; i < test.size(); i++) {
          Strategy strategy = (Strategy) test.get(i);
          Traversal.compute(strategy, inputCg);
        }
      } catch (TraversalException te) {
          // bad traversal path
          //System.out.println("Traversal Error: " + te.getMessage());
          errors.add("Traversal Error: " + te.getMessage());
      } catch (Exception e) {
     	  //System.out.println(e.getMessage());
          errors.add(e.getMessage());
      }
  }
  private void checkDefinesClass(Iterator iter) {
    while (iter.hasNext()) {
      Object next = iter.next();
      if (!inputCg.definesClass(next.toString())) {      
        //System.out.println(next.toString() + " undefined.");
        errors.add(next.toString() + " undefined.");
      }
    }  
  }
  
  // this method has been inserted to manually create the
  // classgraph, since a .jar file is exported and 
  // dj can't do it itself
  private void manuallyCreateClassGraph() {
  	
    String classpath = System.getProperty("java.class.path");
    String[] classpaths=classpath.split(File.pathSeparator);
    int last_slash = classpaths[0].lastIndexOf("\\");
    String sg_path = classpaths[0].substring(0,last_slash)+"\\plugins\\XAspects\\XAspects.jar";

    try	{
    	JarFile jf = new JarFile(new File(sg_path));
    	Enumeration enu = jf.entries();
    	while (enu.hasMoreElements()){
    		String entry = enu.nextElement().toString();
    		//if (entry.indexOf("sg")!=-1 && entry.indexOf("class")!=-1) {
    		if (entry.indexOf("class") != -1) {
    			entry = entry.replace('/', '.');
    			int last_dot = entry.lastIndexOf(".class");
    			entry = entry.substring(0, last_dot);
    			
    			Class cl = Class.forName(entry);
    			runtimeCg.addClass(cl);
    		}
    	}
    }
    catch(Exception e) {
    	System.out.println("open error");
    }

  }
  
  // alternative method for manual ClassGraph creation
  private void manuallyCreateClassGraph2() {
  	
  	// list of classes
  	Class[] classes={ASCII_UCodeESC_CharStream.class, AnyClass.class, AnyPart.class, AspectLanguage.class, AspectLanguage_List.class, BCompound.class, BinaryOp.class, Bypassing.class, ClassDict.class, ClassDictionaryL.class, ClassDictionaryName.class, ClassGlob.class, ClassGlobSet.class, ClassGlobSpec.class, ClassGlob_Commalist.class, ClassName.class, ClassNameExact.class, ClassNameGlob.class, ClassNameSet.class, ClassName_BCList.class, CollectVisitor.class, Complement.class, Constraint.class, CopyVisitor.class, DisplayVisitor.class, EdgeGlob.class, EqualVisitor.class, From.class, Glob.class, GlobSet.class, GlobSpec.class, GlobVisitor.class, Glob_Commalist.class, GraphNodeRegExp.class, GraphNodes.class, Intersect.class, Intersection.class, Join.class, Main.class, Merge.class, Name.class, NameBinding.class, NameBinding_Commalist.class, NameMap.class, NegativeConstraint.class, NodeSubsetDef.class, NodeSubsetDef_List.class, NodeSubsetExpression.class, NodeSubsetExpression_PCList.class, NodeSubsetName.class, Nonempty_AspectLanguage_List.class, Nonempty_ClassGlob_Commalist.class, Nonempty_ClassName_BCList.class, Nonempty_Glob_Commalist.class, Nonempty_Name.class, Nonempty_NameBinding_Commalist.class, Nonempty_NodeSubsetDef_List.class, Nonempty_NodeSubsetExpression_PCList.class, Nonempty_PathSegment_List.class, Nonempty_SGEdge_SList.class, Nonempty_StrategyDef_List.class, Nonempty_Strategy_Commalist.class, OneClassGlob.class, OneGlob.class, OnlyThrough.class, Operator.class, ParseException.class, Parser.class, ParserConstants.class, ParserTokenManager.class, PartGlob.class, PartName.class, PartNameExact.class, PartNameGlob.class, PathDirective.class, PathSegment.class, PathSegment_List.class, PositiveConstraint.class, PrintVisitor.class, SGEdge.class, SGEdge_SList.class, SelectorL.class, SelectorName.class, SemanticChecker.class, Simple.class, SimpleStrategy.class, SourceDirective.class, SourceGlob.class, SourceMarker.class, Strategy.class, StrategyCombination.class, StrategyDef.class, StrategyDef_List.class, StrategyExpression.class, StrategyGraph.class, StrategyName.class, StrategyReference.class, Strategy_Commalist.class, SubclassGlob.class, SubgraphVisitor.class, SuperclassGlob.class, SymbolicNameMap.class, SymbolicNameMapI.class, TargetDirective.class, TargetGlob.class, TargetMarker.class, Through.class, To.class, ToStop.class, Token.class, TokenMgrError.class, TraceVisitor.class, TraversalName.class, UCompound.class, UnaryOp.class, Union.class, UniversalVisitor.class, Via.class, WildCard.class, XAspectLanguage2.class, __Subtraversal.class, __V_ClassGlobSpec_addStrings.class, __V_ClassGlobSpec_map.class, __V_ClassGlobSpec_match.class, __V_ClassGlobSpec_toGlobSpec.class, __V_GlobSpec_collectClassGlobs.class, __V_GlobSpec_collectEdgeGlobs.class, __V_GlobSpec_collectGlobs.class, __V_GlobSpec_match.class, __V_GlobSpec_matchEdge.class, __V_NameMap_buildDict.class, __V_PathDirective_toGraph.class, __V_SGEdge_checkConstraint_Edge.class, __V_SGEdge_checkConstraint_Node.class, __V_Strategy_attachEnv.class };
  	    
  	// add each class to classgraph
  	for (int i = 0; i < classes.length; ++i)
  	    runtimeCg.addClass(classes[i]);

  }
  
  void universal_trv0_bef(UniversalVisitor _v_) {
    ((UniversalVisitor) _v_).before(this);
  }

  void universal_trv0_aft(UniversalVisitor _v_) {
    ((UniversalVisitor) _v_).after(this);
  }

  void universal_trv0(UniversalVisitor _v_) {
    universal_trv0_bef(_v_);
    universal_trv0_aft(_v_);
  }

}