SqlLinq: Taking LINQ to SQL in the Other Direction

using System;
using System.Runtime.InteropServices;

namespace Kackman.Framework.Diagnostics
{
    /// <summary>
    /// A timer that uses the windows tick count
    /// </summary>
    public sealed class TickCountTimer : Timer
    {
        private double m_fLastElapsedTime;
        private double m_fBaseTime;
        private double m_fStopTime;
        private bool m_bTimerStopped;

        [System.Security.SuppressUnmanagedCodeSecurity] // We won't use this maliciously
        [DllImport("winmm.dll")]
        private static extern int timeGetTime();

        /// <summary>
        /// Creates a new instance of the class
        /// </summary>
        public TickCountTimer()
        {
        }

        /// <summary>
        /// <see cref="Timer.Start"/>
        /// </summary>
        public override void Start()
        {
            double time = GetTime();

            if (m_bTimerStopped)
                m_fBaseTime += time - m_fStopTime;

            m_fStopTime = 0.0;
            m_fLastElapsedTime = time;
            m_bTimerStopped = false;
        }

        /// <summary>
        /// <see cref="Timer.Reset"/>
        /// </summary>
        public override void Reset()
        {
            double time = GetTime();

            m_fBaseTime = time;
            m_fLastElapsedTime = time;
            m_fStopTime = 0;
            m_bTimerStopped = false;
        }

        /// <summary>
        /// <see cref="Timer.Stop"/>
        /// </summary>
        public override void Stop()
        {
            if (!m_bTimerStopped)
            {
                double time = GetTime();

                m_fStopTime = time;
                m_fLastElapsedTime = time;
                m_bTimerStopped = true;
            }
        }

        /// <summary>
        /// <see cref="Timer.Advance"/>
        /// </summary>
        public override void Advance()
        {
            m_fStopTime += 0.1;
        }

        /// <summary>
        /// <see cref="Timer.AbsoluteTime"/>
        /// </summary>
        public override double AbsoluteTime
        {
            get
            {
                return GetTime();
            }
        }

        /// <summary>
        /// <see cref="Timer.ElapsedTime"/>
        /// </summary>
        public override double ElapsedTime
        {
            get
            {
                double time = GetTime();
                double fElapsedTime = time - m_fLastElapsedTime;

                m_fLastElapsedTime = time;
                return fElapsedTime;
            }
        }

        /// <summary>
        /// <see cref="Timer.ApplicationTime"/>
        /// </summary>
        public override double ApplicationTime
        {
            get
            {
                return GetTime() - m_fBaseTime;
            }
        }

        private double GetTime()
        {
            if (m_fStopTime != 0.0)
                return m_fStopTime;

            return timeGetTime() * 0.001;
        }
    }
}