package jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.trasnformer;

import java.nio.ByteBuffer;
import fj.Ord;
import fj.data.List;
import fj.data.Option;
import fj.data.TreeMap;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.operations.AppendChildAtOperation;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.operations.DeleteAttributeOperation;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.operations.DeleteChildAtOperation;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.operations.Operation;
import jp.ac.u_ryukyu.ie.cr.shoshi.jungle.store.operations.SetAttributeOperation;

public class EditCache
{
	private final List<Operation> operations;
	private final TreeMap<String,Operation> attrCache;
	private final List<Operation> childrenCache;
	
	public EditCache()
	{
		operations = List.nil();
		attrCache = TreeMap.empty(Ord.stringOrd);
		childrenCache = List.nil();
	}
	
	private EditCache(List<Operation> _operations,TreeMap<String,Operation> _attrCache,List<Operation> _childrenCache)
	{
		operations = _operations;
		attrCache = _attrCache;
		childrenCache = _childrenCache;
	}
	
	public EditCache setAttribute(final String _key,final ByteBuffer _value)
	{
		SetAttributeOperation op = new SetAttributeOperation(){
			@Override
			public String getKey(){
				return _key;
			}
			@Override
			public ByteBuffer getValue(){
				return _value;
			}
		};
		
		TreeMap<String,Operation> newAttrCache = attrCache.set(_key,op);
		List<Operation> newOperations = operations.snoc(op);
		
		return new EditCache(newOperations,newAttrCache,childrenCache);
	}
	
	public EditCache deleteAttribute(final String _key)
	{
		DeleteAttributeOperation op = new DeleteAttributeOperation(){
			@Override
			public String getKey(){
				return _key;
			}
		};
		
		TreeMap<String,Operation> newAttrCache = attrCache.set(_key,op);
		List<Operation> newOperations = operations.snoc(op);
		
		return new EditCache(newOperations,newAttrCache,childrenCache);
	}
	
	public EditCache appendChildAt(final int _pos)
	{
		AppendChildAtOperation op = new AppendChildAtOperation(){
			@Override
			public int position(){
				return _pos;
			}
		};
		
		List<Operation> newOperations = operations.snoc(op);
		List<Operation> newChildrenCache = childrenCache.snoc(op);
		
		return new EditCache(newOperations,attrCache,newChildrenCache);
	}
	
	public EditCache deleteChildAt(final int _pos)
	{
		DeleteChildAtOperation op = new DeleteChildAtOperation(){
			@Override
			public int position(){
				return _pos;
			}
		};
		
		List<Operation> newOperations = operations.snoc(op);
		List<Operation> newChildrenCache = childrenCache.snoc(op);
		
		return new EditCache(newOperations,attrCache,newChildrenCache);
	}
	
	public Operation getAttribute(String _key)
	{
		Option<Operation> result = attrCache.get(_key);
		if(result.isSome()){
			return result.some();
		}
		
		return null;
	}
	
	public List<Operation> operations()
	{
		return operations;
	}
	
	public List<Operation> childrenOperations()
	{
		return childrenCache;
	}
}