package org.randoom.setlx.functions;

import org.randoom.setlx.exceptions.IncompatibleTypeException;
import org.randoom.setlx.types.Value;
import org.randoom.setlx.types.Om;
import org.randoom.setlx.types.SetlList;
import org.randoom.setlx.types.SetlString;
import org.randoom.setlx.utilities.ParameterDef;

import java.util.Collections;
import java.util.List;
import java.util.ArrayList;
import java.util.Iterator;

// sort(collectionValue)     : returns a sorted list of collectionValue.

public class PD_sort extends PreDefinedFunction {
  public final static PreDefinedFunction DEFINITION = new PD_sort();
  
  private PD_sort() {
    super("sort");
    addParameter("collectionValue");
  }
  
  public Value execute(final List<Value> args, final List<Value> writeBackVars) throws IncompatibleTypeException {
    if ( ! (args.get(0) instanceof SetlList || args.get(0) instanceof SetlString)) {
      throw new IncompatibleTypeException("Argument '" +
                                          args.get(0) + "' is not a list or string.");
    }

    if (args.get(0) instanceof SetlList) {

      SetlList collectionValue  = (SetlList)args.get(0);
      
      int size = collectionValue.size();
      List<Value> s = new ArrayList<Value>(size);
      for(Value e: collectionValue) {
        s.add(e);
      }
      Collections.sort(s); // Java inline sort
      
      SetlList s2 = new SetlList(size);
      for(Value e: s) {
        s2.addMember(e);
      }
      
      return s2;

    } else {

      // string
      String str  = args.get(0).getUnquotedString();
      char[] chars = str.toCharArray();
      java.util.Arrays.sort(chars);
      return new SetlString(new String(chars));
      
    }

  }

}