using UnityEngine;
using System.Collections;
using System.Collections.Generic;


namespace JungleDB {
	public class NetworkTransactionManager : TransactionManager {

		private readonly AtomicReference<TreeContext> Repository;
		private readonly TreeContext TContext;
		private readonly ChangeListWriter Writer;
		private readonly string Uuid;
		private readonly string TreeName;

		public NetworkTransactionManager (string name, ChangeListWriter writer, TreeContext tcon, AtomicReference<TreeContext> repo, string uid) {
			this.Repository = repo;
			this.TContext = tcon;
			this.Writer = writer;
			this.Uuid = uid;
			this.TreeName = name;
		}

		public Either<Error, TransactionManager> commit (TreeNode newRoot, TreeOperationLog log) {
			long currentRevision = this.TContext.getRevision();
			long nextRevision = currentRevision + 1;

			ChangeList list = new InnerChangeList(this.Uuid, this.TreeName);

			InterfaceTraverser traverser = new InterfaceTraverser(newRoot, true);
			// not create index.
			TreeContext newTreeContext = new DefaultTreeContext(newRoot, this.TContext, list, this.Uuid, this.TreeName, nextRevision, traverser);
			if (this.Repository.CompareAndSet(newTreeContext.prev(), newTreeContext)) {
				TransactionManager txmanager = new NetworkTransactionManager(this.TreeName, this.Writer, newTreeContext, this.Repository, this.Uuid);
				return DefaultEither<Error, TransactionManager>.newB(txmanager);
			}

			return DefaultEither<Error, TransactionManager>.newA((Error) new DefaultError());
		}

		public long getRevision () {
			return this.TContext.getRevision();
		}

		public string getUUID () {
			return this.Uuid;
		}

		public Either<Error, TransactionManager> firstcommit(TreeNode _newRoot, TreeOperationLog _log) {
			return null;
		}

		public class InnerChangeList : ChangeList {
			string uuid;
			string name;


			IEnumerator IEnumerable.GetEnumerator()
			{
				return this.GetEnumerator();
			}

			public IEnumerator<TreeOperation> GetEnumerator()
			{
				return iterator ();
			}

			// construct
			public InnerChangeList(string _uuid, string _name) {
				this.uuid = _uuid;
				this.name = _name;
			}

			public IEnumerator<TreeOperation> iterator() {
				List<TreeOperation> nil = new List<TreeOperation>();
				return nil.iterator();
			}

			public string uuids() {
				return uuid;
			}

			public string getTreeName() {
				return name;
			}

			public TreeOperationLog getLog() {
				return new DefaultTreeOperationLog();
			}
		}
	}
}