/*
  ks0108.cpp - Arduino library support for ks0108 and compatable graphic LCDs
  Copyright (c)2008 Michael Margolis All right reserved
  mailto:memargolis@hotmail.com?subject=KS0108_Library 

  The high level functions of this library are based on version 1.1 of ks0108 graphics routines
  written and copyright by Fabian Maximilian Thiele. His sitelink is dead but
  you can obtain a copy of his original work here:
  http://www.scienceprog.com/wp-content/uploads/2007/07/glcd_ks0108.zip

  Code changes include conversion to an Arduino C++ library, rewriting the low level routines 
  to read busy status flag and support a wider range of displays, adding more flexibility
  in port addressing and improvements in I/O speed. The interface has been made more Arduino friendly
  and some convenience functions added. 

  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.  

  Version:   1.0 - May 8  2008  - first release
  Version:   1.1 - Nov 7  2008  - restructured low level code to adapt to panel speed
                                 - moved chip and panel configuration into seperate header files    
								 - added fixed width system font
  Version:   2   - May 26 2009   - second release
                                 - added support for Mega and Sanguino, improved panel speed tolerance, added bitmap support
     
*/

#include <inttypes.h>
#include <avr/io.h>
#include <avr/pgmspace.h>
#include <wiring.h>

#define ksSOURCE
#include "ks0108.h"


#define EN_DELAY() asm volatile( "ldi r24, %0 \n\t" "subi r24, 0x1 \n\t" "and r24, r24 \n\t" "brne .-6 \n\t" ::"M" (EN_DELAY_VALUE) : "r24" )
// the (EN_DELAY_VALUE) argument for the above delay is in ks-0108_panel.h

//#define GLCD_DEBUG  // uncomment this if you want to slow down drawing to see how pixels are set

void ks0108::ClearPage(uint8_t page, uint8_t color){
	for(uint8_t x=0; x < DISPLAY_WIDTH; x++){	
	   GotoXY(x, page * 8);
       this->WriteData(color);
   }	
}

void ks0108::ClearScreen(uint8_t color){
 uint8_t page;
   for( page = 0; page < 8; page++){
	  GotoXY(0, page * 8);
	  ClearPage(page, color);
 }
}

void ks0108::DrawLine(uint8_t x1, uint8_t y1, uint8_t x2, uint8_t y2, uint8_t color) {
	uint8_t length, i, y, yAlt, xTmp, yTmp;
	int16_t m;
	//
	// vertical line
	//
	if(x1 == x2) {
		// x1|y1 must be the upper point
		if(y1 > y2) {
			yTmp = y1;
			y1 = y2;
			y2 = yTmp;
		}
		this->DrawVertLine(x1, y1, y2-y1, color);
	
	//
	// horizontal line
	//
	} else if(y1 == y2) {	
		// x1|y1 must be the left point
		if(x1 > x2) {
			xTmp = x1;
			x1 = x2;
			x2 = xTmp;
		}
		this->DrawHoriLine(x1, y1, x2-x1, color);
	
	//
	// angled line :)
	//
	} else {
		// angle >= 45°
		if((y2-y1) >= (x2-x1) || (y1-y2) >= (x2-x1)) {
			// x1 must be smaller than x2
			if(x1 > x2) {
				xTmp = x1;
				yTmp = y1;
				x1 = x2;
				y1 = y2;
				x2 = xTmp;
				y2 = yTmp;
			}
		
			length = x2-x1;		// not really the length :)
			m = ((y2-y1)*200)/length;
			yAlt = y1;
			
			for(i=0; i<=length; i++) {
				y = ((m*i)/200)+y1;
				
				if((m*i)%200 >= 100)
					y++;
				else if((m*i)%200 <= -100)
					y--;
				
				this->DrawLine(x1+i, yAlt, x1+i, y, color);
				
				if(length <= (y2-y1) && y1 < y2)
					yAlt = y+1;
				else if(length <= (y1-y2) && y1 > y2)
					yAlt = y-1;
				else
					yAlt = y;
			}
		
		// angle < 45°
		} else {
			// y1 must be smaller than y2
			if(y1 > y2) {
				xTmp = x1;
				yTmp = y1;
				x1 = x2;
				y1 = y2;
				x2 = xTmp;
				y2 = yTmp;
			}
			
			length = y2-y1;
			m = ((x2-x1)*200)/length;
			yAlt = x1;
			
			for(i=0; i<=length; i++) {
				y = ((m*i)/200)+x1;
				
				if((m*i)%200 >= 100)
					y++;
				else if((m*i)%200 <= -100)
					y--;
				
				this->DrawLine(yAlt, y1+i, y, y1+i, color);
				if(length <= (x2-x1) && x1 < x2)
					yAlt = y+1;
				else if(length <= (x1-x2) && x1 > x2)
					yAlt = y-1;
				else
					yAlt = y;
			}
		}
	}
}

void ks0108::DrawRect(uint8_t x, uint8_t y, uint8_t width, uint8_t height, uint8_t color) {
	DrawHoriLine(x, y, width, color);				// top
	DrawHoriLine(x, y+height, width, color);		// bottom
	DrawVertLine(x, y, height, color);			// left
	DrawVertLine(x+width, y, height, color);		// right
}

void ks0108::DrawRoundRect(uint8_t x, uint8_t y, uint8_t width, uint8_t height, uint8_t radius, uint8_t color) {
  	int16_t tSwitch, x1 = 0, y1 = radius;
  	tSwitch = 3 - 2 * radius;
	
	while (x1 <= y1) {
	    this->SetDot(x+radius - x1, y+radius - y1, color);
	    this->SetDot(x+radius - y1, y+radius - x1, color);

	    this->SetDot(x+width-radius + x1, y+radius - y1, color);
	    this->SetDot(x+width-radius + y1, y+radius - x1, color);
	    
	    this->SetDot(x+width-radius + x1, y+height-radius + y1, color);
	    this->SetDot(x+width-radius + y1, y+height-radius + x1, color);

	    this->SetDot(x+radius - x1, y+height-radius + y1, color);
	    this->SetDot(x+radius - y1, y+height-radius + x1, color);

	    if (tSwitch < 0) {
	    	tSwitch += (4 * x1 + 6);
	    } else {
	    	tSwitch += (4 * (x1 - y1) + 10);
	    	y1--;
	    }
	    x1++;
	}
	  	
	this->DrawHoriLine(x+radius, y, width-(2*radius), color);			// top
	this->DrawHoriLine(x+radius, y+height, width-(2*radius), color);	// bottom
	this->DrawVertLine(x, y+radius, height-(2*radius), color);			// left
	this->DrawVertLine(x+width, y+radius, height-(2*radius), color);	// right
}

/*
 * Hardware-Functions 
 */
void ks0108::FillRect(uint8_t x, uint8_t y, uint8_t width, uint8_t height, uint8_t color) {
	uint8_t mask, pageOffset, h, i, data;
	height++;
	
	pageOffset = y%8;
	y -= pageOffset;
	mask = 0xFF;
	if(height < 8-pageOffset) {
		mask >>= (8-height);
		h = height;
	} else {
		h = 8-pageOffset;
	}
	mask <<= pageOffset;
	
	this->GotoXY(x, y);
	for(i=0; i<=width; i++) {
		data = this->ReadData();
		
		if(color == BLACK) {
			data |= mask;
		} else {
			data &= ~mask;
		}

		this->WriteData(data);
	}
	
	while(h+8 <= height) {
		h += 8;
		y += 8;
		this->GotoXY(x, y);
		
		for(i=0; i<=width; i++) {
			this->WriteData(color);
		}
	}
	
	if(h < height) {
		mask = ~(0xFF << (height-h));
		this->GotoXY(x, y+8);
		
		for(i=0; i<=width; i++) {
			data = this->ReadData();
		
			if(color == BLACK) {
				data |= mask;
			} else {
				data &= ~mask;
			}
	
			this->WriteData(data);
		}
	}
}

void ks0108::InvertRect(uint8_t x, uint8_t y, uint8_t width, uint8_t height) {
	uint8_t mask, pageOffset, h, i, data, tmpData;
	height++;
	
	pageOffset = y%8;
	y -= pageOffset;
	mask = 0xFF;
	if(height < 8-pageOffset) {
		mask >>= (8-height);
		h = height;
	} else {
		h = 8-pageOffset;
	}
	mask <<= pageOffset;
	
	this->GotoXY(x, y);
	for(i=0; i<=width; i++) {
		data = this->ReadData();
		tmpData = ~data;
		data = (tmpData & mask) | (data & ~mask);
		this->WriteData(data);
	}
	
	while(h+8 <= height) {
		h += 8;
		y += 8;
		this->GotoXY(x, y);
		
		for(i=0; i<=width; i++) {
			data = this->ReadData();
			this->WriteData(~data);
		}
	}
	
	if(h < height) {
		mask = ~(0xFF << (height-h));
		this->GotoXY(x, y+8);
		
		for(i=0; i<=width; i++) {
			data = this->ReadData();
			tmpData = ~data;
			data = (tmpData & mask) | (data & ~mask);
			this->WriteData(data);
		}
	}
}

void ks0108::SetInverted(boolean invert) {  // changed type to boolean
	if(this->Inverted != invert) {
		this->InvertRect(0,0,DISPLAY_WIDTH-1,DISPLAY_HEIGHT-1);
		this->Inverted = invert;
	}
}

void ks0108::SetDot(uint8_t x, uint8_t y, uint8_t color) {
	uint8_t data;
	
	this->GotoXY(x, y-y%8);					// read data from display memory
  	
	data = this->ReadData();
	if(color == BLACK) {
		data |= 0x01 << (y%8);				// set dot
	} else {
		data &= ~(0x01 << (y%8));			// clear dot
	}	
	this->WriteData(data);					// write data back to display
}

//
// Font Functions
//

uint8_t ReadPgmData(const uint8_t* ptr) {  // note this is a static function
	return pgm_read_byte(ptr);
}

void ks0108::SelectFont(const uint8_t* font,uint8_t color, FontCallback callback) {
	this->Font = font;
	this->FontRead = callback;
	this->FontColor = color;
}

void ks0108::PrintNumber(long n){
   byte buf[10];  // prints up to 10 digits  
   byte i=0;
   if(n==0)
	   PutChar('0');
   else{
	 if(n < 0){
        PutChar('-');
		n = -n;
	 }
     while(n>0 && i <= 10){
	   buf[i++] = n % 10;  // n % base
	   n /= 10;   // n/= base
	 }
	 for(; i >0; i--)
		 this->PutChar((char) (buf[i-1] < 10 ? '0' + buf[i-1] : 'A' + buf[i-1] - 10));	  
   }
}

int ks0108::PutChar(char c) {
	uint8_t width = 0;
	uint8_t height = this->FontRead(this->Font+FONT_HEIGHT);
	uint8_t bytes = (height+7)/8;
	
	uint8_t firstChar = this->FontRead(this->Font+FONT_FIRST_CHAR);
	uint8_t charCount = this->FontRead(this->Font+FONT_CHAR_COUNT);
	
	uint16_t index = 0;
	uint8_t x = this->Coord.x, y = this->Coord.y;
	
	if(c < firstChar || c >= (firstChar+charCount)) {
		return 1;
	}
	c-= firstChar;

	if( this->FontRead(this->Font+FONT_LENGTH) == 0 && this->FontRead(this->Font+FONT_LENGTH+1) == 0) {
    // zero length is flag indicating fixed width font (array does not contain width data entries)
	   width = this->FontRead(this->Font+FONT_FIXED_WIDTH); 
	   index = c*bytes*width+FONT_WIDTH_TABLE;
	}
	else{
	// variable width font, read width data, to get the index
	   for(uint8_t i=0; i<c; i++) {  
		 index += this->FontRead(this->Font+FONT_WIDTH_TABLE+i);
	   }
	   index = index*bytes+charCount+FONT_WIDTH_TABLE;
	   width = this->FontRead(this->Font+FONT_WIDTH_TABLE+c);
    }

	// last but not least, draw the character
	for(uint8_t i=0; i<bytes; i++) {
		uint8_t page = i*width;
		for(uint8_t j=0; j<width; j++) {
			uint8_t data = this->FontRead(this->Font+index+page+j);
		
			if(height > 8 && height < (i+1)*8) {
				data >>= (i+1)*8-height;
			}
			
			if(this->FontColor == BLACK) {
				this->WriteData(data);
			} else {
				this->WriteData(~data);
			}
		}
		// 1px gap between chars
		if(this->FontColor == BLACK) {
			this->WriteData(0x00);
		} else {
			this->WriteData(0xFF);
		}
		this->GotoXY(x, this->Coord.y+8);
	}
	this->GotoXY(x+width+1, y);

	return 0;
}

void ks0108::Puts(const char* str) {
	int x = this->Coord.x;
	while(*str != 0) {
		if(*str == '\n') {
			this->GotoXY(x, this->Coord.y+this->FontRead(this->Font+FONT_HEIGHT));
		} else {
			this->PutChar(*str);
		}
		str++;
	}
}

void ks0108::Puts_P(PGM_P str) {
	int x = this->Coord.x;
	while(pgm_read_byte(str) != 0) {
		if(pgm_read_byte(str) == '\n') {
			this->GotoXY(x, this->Coord.y+this->FontRead(this->Font+FONT_HEIGHT));
		} else {
			this->PutChar(pgm_read_byte(str));
		}
		str++;
	}
}

uint8_t ks0108::CharWidth(char c) {
	uint8_t width = 0;
	uint8_t firstChar = this->FontRead(this->Font+FONT_FIRST_CHAR);
	uint8_t charCount = this->FontRead(this->Font+FONT_CHAR_COUNT);
	
	// read width data
	if(c >= firstChar && c < (firstChar+charCount)) {
		c -= firstChar;
		width = this->FontRead(this->Font+FONT_WIDTH_TABLE+c)+1;
	}
	
	return width;
}

uint16_t ks0108::StringWidth(char* str) {
	uint16_t width = 0;
	
	while(*str != 0) {
		width += this->CharWidth(*str++);
	}
	
	return width;
}

uint16_t ks0108::StringWidth_P(PGM_P str) {
	uint16_t width = 0;
	
	while(pgm_read_byte(str) != 0) {
		width += this->CharWidth(pgm_read_byte(str++));
	}
	
	return width;
}

void ks0108::CursorTo( uint8_t x, uint8_t y){    // 0 based coordinates for fixed width fonts (i.e. systemFont5x7)
   GotoXY( x * (this->FontRead(this->Font+FONT_FIXED_WIDTH)+1),
	       y * (this->FontRead(this->Font+FONT_HEIGHT)+1)
		 ) ; 
}

void ks0108::GotoXY(uint8_t x, uint8_t y) {
  uint8_t chip, cmd;
	
  if( (x > DISPLAY_WIDTH-1) || (y > DISPLAY_HEIGHT-1) )	// exit if coordinates are not legal
    return;
  this->Coord.x = x;								// save new coordinates
  this->Coord.y = y;
	
  if(y/8 != this->Coord.page) {
  	this->Coord.page = y/8;
	cmd = LCD_SET_PAGE | this->Coord.page;			// set y address on all chips	
	for(chip=0; chip < DISPLAY_WIDTH/CHIP_WIDTH; chip++){
	   this->WriteCommand(cmd, chip);	
	}
  }
  chip = this->Coord.x/CHIP_WIDTH;
  x = x % CHIP_WIDTH;
  cmd = LCD_SET_ADD | x;
  this->WriteCommand(cmd, chip);					// set x address on active chip	
}

void ks0108::Init(boolean invert) {  
	pinMode(D_I,OUTPUT); 	
    pinMode(R_W,OUTPUT); 	
    pinMode(EN,OUTPUT); 	
    pinMode(CSEL1,OUTPUT);
    pinMode(CSEL2,OUTPUT);

	delay(10);

	fastWriteLow(D_I);
	fastWriteLow(R_W);
	fastWriteLow(EN);

	this->Coord.x = 0;
	this->Coord.y = 0;
	this->Coord.page = 0;
	
	this->Inverted = invert;
	
	for(uint8_t chip=0; chip < DISPLAY_WIDTH/CHIP_WIDTH; chip++){
       delay(10);  
	   this->WriteCommand(LCD_ON, chip);				// power on
	   this->WriteCommand(LCD_DISP_START, chip);		// display start line = 0
	}
	delay(50); 
	this->ClearScreen(invert ? BLACK : WHITE);			// display clear
	this->GotoXY(0,0);
}

__inline__ void ks0108::SelectChip(uint8_t chip) {  
//static uint8_t prevchip; 
	if(chipSelect[chip] & 1)
       fastWriteHigh(CSEL1);
	else
	   fastWriteLow(CSEL1);

	if(chipSelect[chip] & 2)
       fastWriteHigh(CSEL2);
	else
	   fastWriteLow(CSEL2);
}


void ks0108::WaitReady( uint8_t chip){
	// wait until LCD busy bit goes to zero

    SelectChip(chip);
	lcdDataDir(0x00);
	fastWriteLow(D_I);	
	fastWriteHigh(R_W);	
	fastWriteHigh(EN); 	
	EN_DELAY();
	while(LCD_DATA_IN_HIGH & LCD_BUSY_FLAG)
		;
	fastWriteLow(EN); 	

	
}

 __inline__ void ks0108::Enable(void) {  
   EN_DELAY();
   fastWriteHigh(EN);					// EN high level width min 450 ns
   EN_DELAY();
   fastWriteLow(EN);
   //EN_DELAY(); // some displays may need this delay at the end of the enable pulse
}

uint8_t ks0108::DoReadData(uint8_t first) {
	uint8_t data, chip;

	chip = this->Coord.x/CHIP_WIDTH;
	this->WaitReady(chip);
	if(first){
		if(this->Coord.x % CHIP_WIDTH == 0 && chip > 0){ 		// todo , remove this test and call GotoXY always?
		  this->GotoXY(this->Coord.x, this->Coord.y);
		  this->WaitReady(chip);
		}
	}	
	fastWriteHigh(D_I);					// D/I = 1
	fastWriteHigh(R_W);					// R/W = 1
	
	fastWriteHigh(EN); 					// EN high level width: min. 450ns
 	EN_DELAY();

#ifdef LCD_DATA_NIBBLES
	 data = (LCD_DATA_IN_LOW & 0x0F) | (LCD_DATA_IN_HIGH & 0xF0);
#else
	 data = LCD_DATA_IN_LOW;	   		// low and high nibbles on same port so read all 8 bits at once
#endif 
	fastWriteLow(EN); 
    if(first == 0) 
	  this->GotoXY(this->Coord.x, this->Coord.y);	
	if(this->Inverted)
		data = ~data;
	return data;
}

inline uint8_t ks0108::ReadData(void) {  
	this->DoReadData(1);				// dummy read
	return this->DoReadData(0);			// "real" read
	this->Coord.x++;
}

void ks0108::WriteCommand(uint8_t cmd, uint8_t chip) {
	 if(this->Coord.x % CHIP_WIDTH == 0 && chip > 0){ 		// todo , ignore address 0???
 	    EN_DELAY();
    }
	this->WaitReady(chip);
	fastWriteLow(D_I);					// D/I = 0
	fastWriteLow(R_W);					// R/W = 0	
    lcdDataDir(0xFF);

EN_DELAY();
    lcdDataOut(cmd);
   this->Enable();						// enable
   EN_DELAY();
   EN_DELAY();
	lcdDataOut(0x00);
}

void ks0108::WriteData(uint8_t data) {
	uint8_t displayData, yOffset, chip;
	//showHex("wrData",data);
    //showXY("wr", this->Coord.x,this->Coord.y);

#ifdef LCD_CMD_PORT	
	uint8_t cmdPort;	
#endif

#ifdef GLCD_DEBUG
	volatile uint16_t i;
	for(i=0; i<5000; i++);
#endif

	if(this->Coord.x >= DISPLAY_WIDTH)
		return;
 chip = this->Coord.x/CHIP_WIDTH; 
 this->WaitReady(chip);


 if(this->Coord.x % CHIP_WIDTH == 0 && chip > 0){ 		// todo , ignore address 0???
	 this->GotoXY(this->Coord.x, this->Coord.y);
 }

	fastWriteHigh(D_I);					// D/I = 1
	fastWriteLow(R_W);  				// R/W = 0	
	lcdDataDir(0xFF);					// data port is output
	
	yOffset = this->Coord.y%8;

	if(yOffset != 0) {
		// first page
#ifdef LCD_CMD_PORT 
		cmdPort = LCD_CMD_PORT;						// save command port
#endif
		displayData = this->ReadData();
#ifdef LCD_CMD_PORT 		
		LCD_CMD_PORT = cmdPort;						// restore command port
#else
	fastWriteHigh(D_I);					// D/I = 1
	fastWriteLow(R_W);					// R/W = 0
	SelectChip(chip);
#endif
		lcdDataDir(0xFF);						// data port is output
		
		displayData |= data << yOffset;
		if(this->Inverted)
			displayData = ~displayData;
		lcdDataOut( displayData);					// write data
		this->Enable();								// enable
		
		// second page
		this->GotoXY(this->Coord.x, this->Coord.y+8);
		
		displayData = this->ReadData();

#ifdef LCD_CMD_PORT 		
		LCD_CMD_PORT = cmdPort;						// restore command port
#else		
	fastWriteHigh(D_I);					// D/I = 1
	fastWriteLow(R_W); 					// R/W = 0	
	SelectChip(chip);
#endif
		lcdDataDir(0xFF);				// data port is output
		
		displayData |= data >> (8-yOffset);
		if(this->Inverted)
			displayData = ~displayData;
		lcdDataOut(displayData);		// write data
		this->Enable();					// enable
		
		this->GotoXY(this->Coord.x+1, this->Coord.y-8);
	}else 
	{
		// just this code gets executed if the write is on a single page
		if(this->Inverted)
			data = ~data;	  
        EN_DELAY();
		lcdDataOut(data);				// write data
		this->Enable();					// enable
		this->Coord.x++;
	    //showXY("WrData",this->Coord.x, this->Coord.y); 
	}
}
void ks0108::DrawBitmap(const uint8_t * bitmap, uint8_t x, uint8_t y, uint8_t color){
uint8_t width, height;
uint8_t i, j;

  width = ReadPgmData(bitmap++); 
  height = ReadPgmData(bitmap++);
  for(j = 0; j < height / 8; j++) {
     this->GotoXY(x, y + (j*8) );
	 for(i = 0; i < width; i++) {
		 uint8_t displayData = ReadPgmData(bitmap++);
	   	 if(color == BLACK)
			this->WriteData(displayData);
		 else
		    this->WriteData(~displayData);
	 }
  }
}

// class wrapper

ks0108::ks0108(){
  this->Inverted=0;
}

// Make one instance for the user
ks0108 GLCD = ks0108();