//--------------------------------------------------------------------------------------
// File: DXUTMisc.h
//
// Helper functions for Direct3D programming.
//
// Copyright (c) Microsoft Corporation. All rights reserved
//--------------------------------------------------------------------------------------
#pragma once
#ifndef DXUT_MISC_H
#define DXUT_MISC_H


//--------------------------------------------------------------------------------------
// A growable array
//--------------------------------------------------------------------------------------
template< typename TYPE >
class CGrowableArray
{
public:
    CGrowableArray()  { m_pData = NULL; m_nSize = 0; m_nMaxSize = 0; }
    ~CGrowableArray() { RemoveAll(); }

    HRESULT SetSize( int nNewMaxSize );
    void    RemoveAll() { SetSize(0); }

protected:
    TYPE* m_pData;      // the actual array of data
    int m_nSize;        // # of elements (upperBound - 1)
    int m_nMaxSize;     // max allocated

    HRESULT SetSizeInternal( int nNewMaxSize );  // This version doesn't call ctor or dtor.
};


//--------------------------------------------------------------------------------------
// Performs timer operations
// Use DXUTGetGlobalTimer() to get the global instance
//--------------------------------------------------------------------------------------
class CDXUTTimer
{
public:
    CDXUTTimer();

    void Reset(); // resets the timer
    void Start(); // starts the timer
    void Stop();  // stop (or pause) the timer
    void Advance(); // advance the timer by 0.1 seconds
    double GetAbsoluteTime(); // get the absolute system time
    double GetTime(); // get the current time
    double GetElapsedTime(); // get the time that elapsed between GetElapsedTime() calls
    bool IsStopped(); // returns true if timer stopped

protected:
    bool m_bUsingQPF;
    bool m_bTimerStopped;
    LONGLONG m_llQPFTicksPerSec;

    LONGLONG m_llStopTime;
    LONGLONG m_llLastElapsedTime;
    LONGLONG m_llBaseTime;
};

//--------------------------------------------------------------------------------------
// Implementation of CGrowableArray
//--------------------------------------------------------------------------------------

// This version doesn't call ctor or dtor.
template< typename TYPE >
HRESULT CGrowableArray<TYPE>::SetSizeInternal( int nNewMaxSize )
{
    if( nNewMaxSize < 0 )
    {
        assert( false );
        return E_INVALIDARG;
    }

    if( nNewMaxSize == 0 )
    {
        // Shrink to 0 size & cleanup
        if( m_pData )
        {
            free( m_pData );
            m_pData = NULL;
        }

        m_nMaxSize = 0;
        m_nSize = 0;
    }
    else if( m_pData == NULL || nNewMaxSize > m_nMaxSize )
    {
        // Grow array
        int nGrowBy = ( m_nMaxSize == 0 ) ? 16 : m_nMaxSize;
        nNewMaxSize = __max( nNewMaxSize, m_nMaxSize + nGrowBy );

        TYPE* pDataNew = (TYPE*) realloc( m_pData, nNewMaxSize * sizeof(TYPE) );
        if( pDataNew == NULL )
            return E_OUTOFMEMORY;

        m_pData = pDataNew;
        m_nMaxSize = nNewMaxSize;
    }

    return S_OK;
}


//--------------------------------------------------------------------------------------
template< typename TYPE >
HRESULT CGrowableArray<TYPE>::SetSize( int nNewMaxSize )
{
    int nOldSize = m_nSize;

    if( nOldSize > nNewMaxSize )
    {
        // Removing elements. Call dtor.

        for( int i = nNewMaxSize; i < nOldSize; ++i )
            m_pData[i].~TYPE();
    }

    // Adjust buffer.  Note that there's no need to check for error
    // since if it happens, nOldSize == nNewMaxSize will be true.)
    HRESULT hr = SetSizeInternal( nNewMaxSize );

    if( nOldSize < nNewMaxSize )
    {
        // Adding elements. Call ctor.

        for( int i = nOldSize; i < nNewMaxSize; ++i )
            ::new (&m_pData[i]) TYPE;
    }

    return hr;
}


#endif