CompositeScope.java

package jetbrains.mps.scope;

/*Generated by MPS */

import java.util.List;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import org.jetbrains.mps.openapi.model.SNode;
import org.jetbrains.annotations.Nullable;
import jetbrains.mps.internal.collections.runtime.ListSequence;
import jetbrains.mps.internal.collections.runtime.Sequence;

public class CompositeScope extends Scope {
  private List<Scope> myScopes;
  public CompositeScope(Scope... scopeChain) {
    myScopes = new ArrayList<Scope>();
    for (Scope scope : scopeChain) {
      if (scope instanceof CompositeScope) {
        myScopes.addAll(((CompositeScope) scope).getScopes());
      } else if (scope != null) {
        myScopes.add(scope);
      }
    }
  }
  public void addScope(Scope scope) {
    if (scope instanceof CompositeScope) {
      myScopes.addAll(((CompositeScope) scope).getScopes());
    } else if (scope != null) {
      myScopes.add(scope);
    }
  }
  public Collection<Scope> getScopes() {
    return Collections.unmodifiableCollection(myScopes);
  }
  @Override
  public SNode resolve(SNode contextNode, String refText) {
    SNode result = null;
    for (Scope scope : myScopes) {
      SNode r = scope.resolve(contextNode, refText);
      if (r != null) {
        if (result == null) {
          result = r;
        } else if (result != r) {
          // ambiguity 
          return null;
        }
      }
    }
    return result;
  }
  @Override
  public Iterable<SNode> getAvailableElements(@Nullable String prefix) {
    List<SNode> result = new ArrayList<SNode>();
    for (Scope scope : myScopes) {
      ListSequence.fromList(result).addSequence(Sequence.fromIterable(scope.getAvailableElements(prefix)));
    }
    return result;
  }
  @Override
  public String getReferenceText(SNode contextNode, SNode node) {
    String result = null;
    for (Scope scope : myScopes) {
      String refText = scope.getReferenceText(contextNode, node);
      if (refText != null) {
        if (result == null) {
          result = refText;
        } else {
          // ambiguity 
          return null;
        }
      }
    }
    return result;
  }
  public static Scope createComposite(Scope... scopes) {
    Scope last = null;
    for (Scope s : scopes) {
      if (s == null) {
        continue;
      }
      if (last == null) {
        last = s;
      } else if (last instanceof CompositeScope) {
        ((CompositeScope) last).addScope(s);
      } else if (s instanceof CompositeScope) {
        ((CompositeScope) s).addScope(last);
        last = s;
      } else {
        last = new CompositeScope(last, s);
      }
    }
    return last;
  }
}