Files
CypherCore/Source/Framework/Database/QueryCallback.cs
T
2021-11-15 16:11:20 -05:00

104 lines
3.0 KiB
C#

/*
* Copyright (C) 2012-2020 CypherCore <http://github.com/CypherCore>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
using System;
using System.Collections.Generic;
using System.Threading.Tasks;
namespace Framework.Database
{
public class QueryCallback : ISqlCallback
{
public QueryCallback(Task<SQLResult> result)
{
_result = result;
}
public QueryCallback WithCallback(Action<SQLResult> callback)
{
return WithChainingCallback((queryCallback, result) => callback(result));
}
public QueryCallback WithCallback<T>(Action<T, SQLResult> callback, T obj)
{
return WithChainingCallback((queryCallback, result) => callback(obj, result));
}
public QueryCallback WithChainingCallback(Action<QueryCallback, SQLResult> callback)
{
_callbacks.Enqueue(new QueryCallbackData(callback));
return this;
}
public void SetNextQuery(QueryCallback next)
{
_result = next._result;
}
public bool InvokeIfReady()
{
QueryCallbackData callback = _callbacks.Peek();
while (true)
{
if (_result != null && _result.Wait(0))
{
Task<SQLResult> f = _result;
Action<QueryCallback, SQLResult> cb = callback._result;
_result = null;
cb(this, f.Result);
_callbacks.Dequeue();
bool hasNext = _result != null;
if (_callbacks.Count == 0)
{
Cypher.Assert(!hasNext);
return true;
}
// abort chain
if (!hasNext)
return true;
callback = _callbacks.Peek();
}
else
return false;
}
}
Task<SQLResult> _result;
Queue<QueryCallbackData> _callbacks = new();
}
struct QueryCallbackData
{
public QueryCallbackData(Action<QueryCallback, SQLResult> callback)
{
_result = callback;
}
public void Clear()
{
_result = null;
}
public Action<QueryCallback, SQLResult> _result;
}
}