/*
Thor Server Project
Copyright 2008 Joe Hegarty


This file is part of The Thor Server Project.

The Thor Server Project is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

The Thor Server Project 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 Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with The Thor Server Project.  If not, see <http://www.gnu.org/licenses/>.
*/

using System;
using System.Collections.Generic;
using System.Text;

namespace ThorServer.Utilities
{
    public static class HighResolutionTime
    {
        [System.Runtime.InteropServices.DllImport("Kernel32.dll")]
        private static extern bool QueryPerformanceCounter(out long perfcount);

        [System.Runtime.InteropServices.DllImport("Kernel32.dll")]
        private static extern bool QueryPerformanceFrequency(out long freq);

        private static long mStartCounter;
        private static long mFrequency;

        static HighResolutionTime()
        {
            QueryPerformanceFrequency(out mFrequency);
        }

        public static void Start()
        {
            QueryPerformanceCounter(out mStartCounter);
        }

        public static double GetTime()
        {
            long endCounter;
            QueryPerformanceCounter(out endCounter);
            long elapsed = endCounter - mStartCounter;
            return (double) elapsed / mFrequency;
        }
    }
}