package jp.ac.u_ryukyu.ie.cr.tatsuki.jungle.store.index;

import java.util.Iterator;

import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.impl.TreeNode;
import fj.Ord;
import fj.P2;
import fj.data.List;
import fj.data.Option;
import fj.data.TreeMap;

public class Index {

  TreeMap<String, TreeMap<String, List<TreeNode>>> indexList;

  public Index() {
    this.indexList = TreeMap.empty(Ord.stringOrd);
  }

  public Index(TreeMap<String, TreeMap<String, List<TreeNode>>> indexList) {
    this.indexList = indexList;
  }

  public Index(Index indexList) {
    this.indexList = indexList.getIndex();
  }

  public Index set(String key, String value, TreeNode node) {
    Option<TreeMap<String, List<TreeNode>>> indexOp = indexList.get(key);
    if (indexOp.isNone())
      return this;

    TreeMap<String, List<TreeNode>> index = indexOp.some();
    Option<List<TreeNode>> nodeListOp = index.get(value);

    List<TreeNode> newNodeList;
    if (nodeListOp.isSome()) {
      List<TreeNode> nodeList = nodeListOp.some();
      newNodeList = nodeList.cons(node);
    } else {
      List<TreeNode> nodeList = List.nil();
      newNodeList = nodeList.cons(node);
    }
    TreeMap<String, List<TreeNode>> newIndex = index.set(value, newNodeList);
    TreeMap<String, TreeMap<String, List<TreeNode>>> newIndexList = indexList.set(key, newIndex);
    return new Index(newIndexList);
  }

  public Index delete(String key, String value, TreeNode node) {
    Option<TreeMap<String, List<TreeNode>>> indexOp = indexList.get(key);
    if (indexOp.isNone())
      return this;

    TreeMap<String, List<TreeNode>> index = indexOp.some();
    TreeMap<String, List<TreeNode>> newIndex = index;
    Option<List<TreeNode>> nodeListOp = index.get(value);
    if (nodeListOp.isSome()) {
      List<TreeNode> nodeList = nodeListOp.some();
      List<TreeNode> newNodeList = List.nil();
      for (TreeNode indexingNode : nodeList) {
        if (indexingNode.equals(node))
          newNodeList = newNodeList.cons(indexingNode);
      }

      newIndex = index.set(value, newNodeList);
    } else {
      return this;
    }
    TreeMap<String, TreeMap<String, List<TreeNode>>> newIndexList = indexList.set(key, newIndex);
    return new Index(newIndexList);
  }

  public Index deleteNodeAll(TreeNode node) {
    List<String> keys = node.getAttributes().getKeys();
    TreeMap<String, TreeMap<String, List<TreeNode>>> newIndexList = indexList;

    for (String key : keys) {
      Option<TreeMap<String, List<TreeNode>>> indexOp = indexList.get(key);
      if (indexOp.isNone())
        continue;

      TreeMap<String, List<TreeNode>> index = indexOp.some();
      Iterator<P2<String, List<TreeNode>>> indexIterator = index.iterator();

      TreeMap<String, List<TreeNode>> newIndex = index;
      for (; indexIterator.hasNext();) {
        List<TreeNode> newNodeList = List.nil();
        P2<String, List<TreeNode>> NodeListP2 = indexIterator.next();
        String value = NodeListP2._1();
        List<TreeNode> targetNodeList = NodeListP2._2();
        for (TreeNode targetNode : targetNodeList) {
          if (!node.equals(targetNode))
            newNodeList = newNodeList.cons(targetNode);
        }
        newIndex = newIndex.set(value, newNodeList);
      }
      newIndexList = indexList.set(key, newIndex);
    }

    return new Index(newIndexList);
  }


  public Index putNodeAll(TreeNode node) {
    List<String> keys = node.getAttributes().getKeys();
    TreeMap<String, TreeMap<String, List<TreeNode>>> newIndexList = indexList;
    
    for (String key : keys) {
      
      String value = node.getAttributes().getString(key);
      if (value == null)
        continue;
      
      Option<TreeMap<String, List<TreeNode>>> indexOp = indexList.get(key);
      if (indexOp.isNone())
        continue;

      TreeMap<String, List<TreeNode>> index = indexOp.some(); 
      Option<List<TreeNode>> nodeListOp = index.get(value);
      TreeMap<String, List<TreeNode>> newIndex = index;
      
      if (nodeListOp.isNone()) {
        List<TreeNode> newNodeList = List.nil();
        newNodeList = newNodeList.cons(node);
        newIndex = newIndex.set(value, newNodeList);
      } else {
        List<TreeNode> newNodeList = nodeListOp.some();
        newNodeList = newNodeList.cons(node);
        newIndex = newIndex.set(value, newNodeList);
      }
           
      newIndexList = newIndexList.set(key, newIndex);
    }
    return new Index(newIndexList);
  }
  
  public List<TreeNode> get(String key, String value) {
    Option<TreeMap<String, List<TreeNode>>> indexOp = indexList.get(key);
    if (indexOp.isNone())
      return List.nil();

    TreeMap<String, List<TreeNode>> index = indexOp.some();
    Option<List<TreeNode>> nodeListOp = index.get(value);

    if (nodeListOp.isNone())
      return List.nil();

    return nodeListOp.some();
  }
  
  
  private TreeMap<String, TreeMap<String, List<TreeNode>>> getIndex() {
    return indexList;
  }
  
}