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// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_sc.hxx"



// INCLUDE ---------------------------------------------------------------

#include <vcl/outdev.hxx>

#include "drawutil.hxx"
#include "document.hxx"
#include "global.hxx"
#include "viewdata.hxx"

// STATIC DATA -----------------------------------------------------------

// -----------------------------------------------------------------------


inline Fraction MakeFraction( long nA, long nB )
{
	return ( nA && nB ) ? Fraction(nA,nB) : Fraction(1,1);
}

void ScDrawUtil::CalcScale( ScDocument* pDoc, SCTAB nTab,
							SCCOL nStartCol, SCROW nStartRow, SCCOL nEndCol, SCROW nEndRow,
							OutputDevice* pDev,
							const Fraction& rZoomX, const Fraction& rZoomY,
							double nPPTX, double nPPTY,
							Fraction& rScaleX, Fraction& rScaleY )
{
	long nPixelX = 0;
	long nTwipsX = 0;
	long nPixelY = 0;
	long nTwipsY = 0;
	for (SCCOL i=nStartCol; i<nEndCol; i++)
	{
		sal_uInt16 nWidth = pDoc->GetColWidth(i,nTab);
		nTwipsX += (long) nWidth;
		nPixelX += ScViewData::ToPixel( nWidth, nPPTX );
	}

    for (SCROW nRow = nStartRow; nRow <= nEndRow-1; ++nRow)
	{
        SCROW nLastRow = nRow;
        if (pDoc->RowHidden(nRow, nTab, NULL, &nLastRow))
        {    
            nRow = nLastRow;
            continue;
        }

        sal_uInt16 nHeight = pDoc->GetRowHeight(nRow, nTab);
        nTwipsY += static_cast<long>(nHeight);
        nPixelY += ScViewData::ToPixel(nHeight, nPPTY);
	}

    // #i116848# To get a large-enough number for PixelToLogic, multiply the integer values
    // instead of using a larger number of rows
    if ( nTwipsY )
    {
        long nMultiply = 2000000 / nTwipsY;
        if ( nMultiply > 1 )
        {
            nTwipsY *= nMultiply;
            nPixelY *= nMultiply;
        }
    }

	MapMode aHMMMode( MAP_100TH_MM, Point(), rZoomX, rZoomY );
	Point aPixelLog = pDev->PixelToLogic( Point( nPixelX,nPixelY ), aHMMMode );

	//	Fraction(double) ctor can be used here (and avoid overflows of PixelLog * Zoom)
	//	because ReduceInaccurate is called later anyway.

	if ( aPixelLog.X() && nTwipsX )
		rScaleX = Fraction( ((double)aPixelLog.X()) *
							((double)rZoomX.GetNumerator()) /
							((double)nTwipsX) /
							((double)HMM_PER_TWIPS) /
							((double)rZoomX.GetDenominator()) );
	else
		rScaleX = Fraction( 1, 1 );

	if ( aPixelLog.Y() && nTwipsY )
		rScaleY = Fraction( ((double)aPixelLog.Y()) *
							((double)rZoomY.GetNumerator()) /
							((double)nTwipsY) /
							((double)HMM_PER_TWIPS) /
							((double)rZoomY.GetDenominator()) );
	else
		rScaleY = Fraction( 1, 1 );

    //	25 bits of accuracy are needed to always hit the right part of
    //	cells in the last rows (was 17 before 1M rows).
	rScaleX.ReduceInaccurate( 25 );
	rScaleY.ReduceInaccurate( 25 );
}