/*  PageRenderer.cpp
 *
 *  Copyright (C) 2013-2016  Jim Evins <evins@snaught.com>
 *
 *  This file is part of gLabels-qt.
 *
 *  gLabels-qt 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.
 *
 *  gLabels-qt 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 gLabels-qt.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "PageRenderer.h"


#include <QtDebug>

#include "LabelModel.h"

#include "Merge/Merge.h"
#include "Merge/None.h"
#include "Merge/Record.h"


namespace glabels
{
	
	//
	// Private
	//
	namespace
	{
		const QColor labelOutlineColor( 0, 0, 0 );
		const double labelOutlineWidth = 0.25;
		const double tickOffset = 2.25;
		const double tickLength = 18;
	}


	PageRenderer::PageRenderer()
		: mModel(0), mNCopies(0), mStartLabel(0),
		  mPrintOutlines(false), mPrintCropMarks(false), mPrintReverse(false),
		  mIsMerge(false), mIPage(0), mNPages(0)
	{
		// empty
	}


	void PageRenderer::setModel( const LabelModel* model )
	{
		mModel = model;

		connect( mModel, SIGNAL(changed()), this, SLOT(onModelChanged()) );
	
		onModelChanged();
	}

	
	const LabelModel* PageRenderer::model() const
	{
		return mModel;
	}


	void PageRenderer::onModelChanged()
	{
		mMerge = mModel->merge();
		mOrigins = mModel->frame()->getOrigins();
		mNLabelsPerPage = mModel->frame()->nLabels();
		mIsMerge = ( dynamic_cast<const merge::None*>(mMerge) == 0 );
		updateNPages();

		emit changed();
	}


	void PageRenderer::setNCopies( int nCopies )
	{
		mNCopies = nCopies;
		updateNPages();

		emit changed();
	}


	void PageRenderer::setStartLabel( int startLabel )
	{
		mStartLabel = startLabel;
		updateNPages();

		emit changed();
	}

	
	void PageRenderer::setPrintOutlines( bool printOutlinesFlag )
	{
		mPrintOutlines = printOutlinesFlag;

		emit changed();
	}

	
	void PageRenderer::setPrintCropMarks( bool printCropMarksFlag )
	{
		mPrintCropMarks = printCropMarksFlag;

		emit changed();
	}

	
	void PageRenderer::setPrintReverse( bool printReverseFlag )
	{
		mPrintReverse = printReverseFlag;

		emit changed();
	}

	
	void PageRenderer::setIPage( int iPage )
	{
		mIPage = iPage;

		emit changed();
	}

	
	int PageRenderer::nItems() const
	{
		return mLastLabel - mStartLabel;
	}
			
	
	int PageRenderer::nPages() const
	{
		return mNPages;
	}
			
	
	QRectF PageRenderer::pageRect() const
	{
		if ( mModel )
		{
			return QRectF( 0, 0, mModel->tmplate()->pageWidth().pt(), mModel->tmplate()->pageHeight().pt() );
		}
		else
		{
			return QRectF( 0, 0, 0, 0 );
		}
	}
			
	
	void PageRenderer::updateNPages()
	{
		if ( mModel )
		{
			if ( mIsMerge )
			{
				mLastLabel = mStartLabel + mNCopies*mMerge->nSelectedRecords();
			}
			else
			{
				mLastLabel = mStartLabel + mNCopies;
			}
		
			mNPages = mLastLabel / mNLabelsPerPage;
			if ( mLastLabel % mNLabelsPerPage )
			{
				mNPages++;
			}
		}
		else
		{
			mNPages = 0;
		}
	}

	
	///
	/// Print page using persistent page number
	///
	void PageRenderer::printPage( QPainter* painter ) const
	{
		printPage( painter, mIPage );
	}


	///
	/// Print page
	///
	void PageRenderer::printPage( QPainter* painter, int iPage ) const
	{
		if ( mModel )
		{
			if ( mIsMerge )
			{
				printMergePage( painter, iPage );
			}
			else
			{
				printSimplePage( painter, iPage );
			}
		}
	}


	void PageRenderer::printSimplePage( QPainter* painter, int iPage ) const
	{
		int iStart = 0;
		int iEnd = mNLabelsPerPage;

		if ( iPage == 0 )
		{
			iStart = mStartLabel;
		}

		if ( (mLastLabel / mNLabelsPerPage) == iPage )
		{
			iEnd = mLastLabel % mNLabelsPerPage;
		}

		printCropMarks( painter );

		for ( int i = iStart; i < iEnd; i++ )
		{
			painter->save();

			painter->translate( mOrigins[i].x().pt(), mOrigins[i].y().pt() );
			
			painter->save();

			clipLabel( painter );
			printLabel( painter, 0 );

			painter->restore();  // From before clip

			printOutline( painter );
			
			painter->restore();  // From before translation
		}
	}

	
	void PageRenderer::printMergePage( QPainter* painter, int iPage ) const
	{
		int iRecord = 0;
		int iStart = 0;
		int iEnd = mNLabelsPerPage;

		if ( iPage == 0 )
		{
			iStart = mStartLabel;
		}

		if ( (mLastLabel / mNLabelsPerPage) == iPage )
		{
			iEnd = mLastLabel % mNLabelsPerPage;
		}

		const QList<merge::Record*> records = mMerge->selectedRecords();
		if ( records.size() )
		{
			iRecord = (iPage*mNLabelsPerPage + iStart - mStartLabel) % records.size();
		}

		printCropMarks( painter );

		for ( int i = iStart; i < iEnd; i++ )
		{
			painter->save();

			painter->translate( mOrigins[i].x().pt(), mOrigins[i].y().pt() );
			
			painter->save();

			clipLabel( painter );
			printLabel( painter, records[iRecord] );

			painter->restore();  // From before clip

			printOutline( painter );
			
			painter->restore();  // From before translation

			iRecord = (iRecord + 1) % records.size();
		}
	}
	
	
	void PageRenderer::printCropMarks( QPainter* painter ) const
	{
		if ( mPrintCropMarks )
		{
			painter->save();

			painter->setBrush( QBrush( Qt::NoBrush ) );
			painter->setPen( QPen( labelOutlineColor, labelOutlineWidth ) );

			Distance w = mModel->frame()->w();
			Distance h = mModel->frame()->h();

			foreach ( Layout* layout, mModel->frame()->layouts() )
			{
				Distance xMin = layout->x0();
				Distance yMin = layout->y0();
				Distance xMax = layout->x0() + layout->dx()*(layout->nx()-1) + w;
				Distance yMax = layout->y0() + layout->dy()*(layout->ny()-1) + h;

				for ( int ix = 0; ix < layout->nx(); ix++ )
				{
					Distance x1 = xMin + ix*layout->dx();
					Distance x2 = x1 + w;

					Distance y1 = max( yMin-tickOffset, Distance::pt(0) );
					Distance y2 = max( y1-tickLength, Distance::pt(0) );

					Distance y3 = min( yMax+tickOffset, mModel->tmplate()->pageHeight() );
					Distance y4 = min( y3+tickLength, mModel->tmplate()->pageHeight() );

					painter->drawLine( x1.pt(), y1.pt(), x1.pt(), y2.pt() );
					painter->drawLine( x2.pt(), y1.pt(), x2.pt(), y2.pt() );
					painter->drawLine( x1.pt(), y3.pt(), x1.pt(), y4.pt() );
					painter->drawLine( x2.pt(), y3.pt(), x2.pt(), y4.pt() );
				}

				for ( int iy = 0; iy < layout->ny(); iy++ )
				{
					Distance y1 = yMin + iy*layout->dy();
					Distance y2 = y1 + h;

					Distance x1 = max( xMin-tickOffset, Distance::pt(0) );
					Distance x2 = max( x1-tickLength, Distance::pt(0) );

					Distance x3 = min( xMax+tickOffset, mModel->tmplate()->pageWidth() );
					Distance x4 = min( x3+tickLength, mModel->tmplate()->pageWidth() );

					painter->drawLine( x1.pt(), y1.pt(), x2.pt(), y1.pt() );
					painter->drawLine( x1.pt(), y2.pt(), x2.pt(), y2.pt() );
					painter->drawLine( x3.pt(), y1.pt(), x4.pt(), y1.pt() );
					painter->drawLine( x3.pt(), y2.pt(), x4.pt(), y2.pt() );
				}
			}

			painter->restore();
		}
	}

	
	void PageRenderer::printOutline( QPainter* painter ) const
	{
		if ( mPrintOutlines )
		{
			painter->save();

			painter->setBrush( QBrush( Qt::NoBrush ) );
			painter->setPen( QPen( labelOutlineColor, labelOutlineWidth ) );

			painter->drawPath( mModel->frame()->path() );
			
			painter->restore();
		}
	}

	
	void PageRenderer::clipLabel( QPainter* painter ) const
	{
		painter->setClipPath( mModel->frame()->clipPath() );
	}

	
	void PageRenderer::printLabel( QPainter* painter, merge::Record* record ) const
	{
		painter->save();

		if ( mModel->rotate() )
		{
			painter->rotate( -90.0 );
			painter->translate( -mModel->w().pt(), 0 );
		}

		if ( mPrintReverse )
		{
			painter->translate( mModel->w().pt(), 0 );
			painter->scale( -1, 1 );
		}

		mModel->draw( painter, false, record );

		painter->restore();
	}

}