/*
MD_Parola - Library for modular scrolling text and Effects
  
See header file for comments
  
Copyright (C) 2013 Marco Colli. All rights reserved.

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library 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
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <MD_Parola.h>
#include <MD_Parola_lib.h>
/**
 * \file
 * \brief Implements horizontal scrolling effect
 */

#define	START_POSITION		(bLeft) ? ZONE_START_COL(_zoneStart) : ZONE_END_COL(_zoneEnd)	///< Start position depends on the scrolling direction

void MD_PZone::effectHScroll(bool bLeft, bool bIn)
{
	if (bIn)
	{
		switch(_fsmState)
		{
		case INITIALISE:
		case GET_FIRST_CHAR: // Load the first character from the font table
			PRINT_STATE("I HSCROLL");

			if ((_charCols = getFirstChar()) == 0)
			{
				_fsmState = END;
				break;
			}
			_countCols = 0;
			_fsmState = PUT_CHAR;
			break;

		case GET_NEXT_CHAR:	// Load the next character from the font table
			PRINT_STATE("I HSCROLL");

			// Have we reached the end of the characters string?
			_charCols = getNextChar();
			FSMPRINT("\ncharCols ", _charCols);
			if (_charCols == 0)
			{
				_fsmState = PAUSE;
				break;
			}

			_countCols = 0;
			_fsmState = PUT_CHAR;
			FSMPRINTS(", fall thru");
			// !! fall through to next state to start displaying

		case PUT_CHAR:	// display the next part of the character
			PRINT_STATE("I HSCROLL");

			_MX->transform(_zoneStart, _zoneEnd, bLeft ? MD_MAX72XX::TSL : MD_MAX72XX::TSR);
			_MX->setColumn(START_POSITION, DATA_BAR(_cBuf[_countCols++]));
			FSMPRINTS(", scroll");

			// end of this buffer - we may need to get another one
			if (_countCols == _charCols)
			{
				if (!_endOfText)
					_fsmState = GET_NEXT_CHAR;
				else
				{
					// work out the number of filler columns
					_countCols = (bLeft ? _limitLeft-_textLen-ZONE_START_COL(_zoneStart) : ZONE_END_COL(_zoneEnd)-_limitLeft);
					FSMPRINT(", filler count ", _countCols);
					_fsmState = (_countCols <= 0) ? PAUSE : PUT_FILLER;
				}
			}
		break;

		case PUT_FILLER:		// keep sending out blank columns until aligned
			PRINT_STATE("I HSCROLL");

			_MX->transform(_zoneStart, _zoneEnd, bLeft ? MD_MAX72XX::TSL : MD_MAX72XX::TSR);
			_MX->setColumn(START_POSITION, EMPTY_BAR);
			FSMPRINTS(", fill");

			if (--_countCols == 0)
				_fsmState = PAUSE;
		break;

		default:
			_fsmState = PAUSE;
			break;
	  }
	}
	else	// exiting
	{
		bool	b;

		switch(_fsmState)
		{
		case PAUSE:
			PRINT_STATE("O HSCROLL");
			_fsmState = PUT_FILLER;
			FSMPRINTS(" falling thru");
			// fall through

		case PUT_FILLER:
			PRINT_STATE("O HSCROLL");
			_MX->transform(_zoneStart, _zoneEnd, bLeft ? MD_MAX72XX::TSL : MD_MAX72XX::TSR);
			_MX->setColumn(START_POSITION, EMPTY_BAR);

			// check if enough scrolled off to say that new message should start
      // how we count depends on the direction for scrolling
      {
        uint16_t  spaceCount = 0;
        uint16_t  maxCount = (_zoneEnd - _zoneStart + 1) * COL_SIZE;
        
        if ((_scrollDistance != 0) && (maxCount > _scrollDistance)) maxCount = _scrollDistance; 
        
        if (bLeft)
        {
			    for (int16_t i = ZONE_START_COL(_zoneStart); 
              (i <= ZONE_END_COL(_zoneEnd)) && (_MX->getColumn(i) == EMPTY_BAR); 
               i++, spaceCount++);
        }
        else
        {
			    for (int16_t i = ZONE_END_COL(_zoneEnd);
			        (i >= ZONE_START_COL(_zoneStart)) && (_MX->getColumn(i) == EMPTY_BAR);
			        i--, spaceCount++);
        }
     
			  if (maxCount <= spaceCount) _fsmState = END;	// enough of a space between messages, end this FSM
      }      
			break;

		default:
			_fsmState = END;
			break;
		}
	}
}
