package alice.jungle.persistent;

import java.util.Iterator;
import java.util.concurrent.ConcurrentHashMap;

import fj.Ord;
import fj.data.List;
import fj.data.TreeMap;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.Jungle;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.JungleTree;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.persistent.ChangeList;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.TreeContext;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.TreeEditor;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.impl.TreeNode;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.operations.TreeOperation;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.transaction.DefaultTreeNode;
import jp.ac.u_ryukyu.ie.cr.tatsuki.jungle.store.index.ParentIndex;

public class PersistentJungle implements Jungle {
  private PersistentJournal journal;
  private ConcurrentHashMap<String, JungleTree> trees;
  final private String uuid;
  private TreeEditor editor;

  public PersistentJungle(PersistentJournal _journal, String _uuid, TreeEditor _editor) {
    journal = _journal;
    trees = new ConcurrentHashMap<String, JungleTree>();
    uuid = _uuid;
    editor = _editor;
  }

  @Override
  public JungleTree getTreeByName(String _name) {
    return trees.get(_name);
  }

  @Override
  public JungleTree createNewTree(final String name) {
    ChangeList list = new ChangeList() {
      @Override
      public Iterator<TreeOperation> iterator() {
        List<TreeOperation> nil = List.nil();
        return nil.iterator();
      }

      @Override
      public String uuid() {
        return uuid;
      }

      @Override
      public String getTreeName() {
        return name;
      }
    };
    TreeNode root = new DefaultTreeNode();
    TreeMap<String, TreeMap<String, TreeMap<TreeNode, TreeNode>>> indexList = TreeMap.empty(Ord.stringOrd);
    TreeMap<TreeNode, TreeNode> parentIndex = new ParentIndex().getParentIndex();
    TreeContext tc = new PersistentTreeContext(root, null, list, uuid, name, 0, indexList, parentIndex);
    JungleTree newTree = new PersistentJungleTree(name, tc, uuid, journal.getWriter(), editor);
    if (trees.putIfAbsent(name, newTree) != null) {
      return null;
    }
    return newTree;
  }

}