extern "C" {
	#include <Wire/Wire.h>
}

#include "twiLCD.h"

#ifdef TWI_LCD_DPOT_CTRL
#include "../ds1803/ds1803.h"
#endif

twiLCD::twiLCD()
{
#if defined(__AVR_ATmega168__) && !defined(TWI_LCD_SMALL)
	#if defined(TWI_LCD_CTRL) && !defined(TWI_LCD_BL_PWM)
		backlightStatus = 0;
	#endif
	
	#ifdef TWI_LCD_BL_PWM
		pinMode(TWI_LCD_BACKLIGHT, HIGH);
	#endif
	
	displayStatus = false;
#endif

#ifdef WIRE_LIB_SCAN_MOD
	/*if (!Wire.isStarted())*/ Wire.begin();
#else
	Wire.begin();
#endif
}

twiLCD LCD = twiLCD();

void twiLCD::Init() {
#ifdef TWI_LCD_CTRL
	backlightOff();
#ifdef TWI_LCD_DPOT_CTRL
	setBrightness(0);
#endif
#endif
	delay(20);
/////////// 4 pin initialization
	writeCommand(0x03); // function set: 4 pin initialization
	delay(5);
	writeCommand(0x03); // function set: 4 pin initialization
	delay(1);
	writeCommand(0x03); // function set: 4 pin initialization
	delay(1);
	writeCommand(0x02); // function set: 4 pin initialization
/////////// end of 4 pin initialization 
	
	
	writeCommand(LCD_FUNCTION_SET); // function set: 4-bit interface, 1 display lines, 5x7 font
	writeCommand(LCD_ENTRY_MODE);
	writeCommand(LCD_CURSOR);
	clearScreen();
	
	writeCommand(LCD_CLOSE_INIT);
	
#if defined(__AVR_ATmega168__) && !defined(TWI_LCD_SMALL)
#ifdef TWI_LCD_CTRL
	#if defined(TWI_LCD_BL_PWM) || defined(TWI_LCD_DPOT_CTRL)
		#ifdef TWI_LCD_DPOT_CTRL
			setBrightness();
		#endif
		backlightOn(TWI_LCD_BL_LEVEL);
	#else
		backlightOn();
	#endif
#endif

	displayStatus = true;
#endif
}

boolean twiLCD::checkLCDBusy(void)
{
	Wire.requestFrom(PCF8574_RADDR, 1);
	
	while (!Wire.available());
	
	return (Wire.receive() & TWI_LCD_BUSY ? true : false);
}

void twiLCD::writeCommand(uint8_t value)
{
	int value1	= 0;
	int control	= 0; // stores RS and RW
		
#ifdef TWI_LCD_USE_TIMEOUT
	previousMillis	= millis();
#endif
	
	control	= value >> 8;	// get the control signals RS and RW
	control	>>= 5;			// shift the control signals to the left
  
	Wire.beginTransmission(PCF8574_WADDR);
	
	value1	= value;
	cbi(value1, TWI_LCD_DATAL); // Turn off LByte
	
	cbi(value1, TWI_LCD_RS);
	cbi(value1, TWI_LCD_RW);
	
	sendPulse(value1);
	
	delay(1);
	
	cbi(value, TWI_LCD_DATAH);	// Turn off HByte
	value <<= 4;
	
	cbi(value, TWI_LCD_RS);
	cbi(value, TWI_LCD_RW);
	
	sendPulse(value);
	
	Wire.endTransmission();
	
	delay(1);
}

void twiLCD::writeData(uint8_t value)
{
	int value1	= 0;
	int control	= 0; // stores RS and RW
	
	// Wait for the LCD to be ready
	
#ifdef TWI_LCD_USE_TIMEOUT
	previousMillis	= millis();
#endif

	control	= value >> 8;	// get the control signals RS and RW
	control	>>= 5;			// shift the control signals to the left
	
	value1	= value;
	cbi(value1, TWI_LCD_DATAL); // Turn off LByte
	sbi(value1, TWI_LCD_RS);
	cbi(value1, TWI_LCD_RW);
	
	while (checkLCDBusy());
	
	Wire.beginTransmission(PCF8574_WADDR);
	sendPulse(value1);
	
	delay(1);
	
	cbi(value, TWI_LCD_DATAH);	// Turn off HByte
	value	<<= 4;
	
	sbi(value, TWI_LCD_RS);
	cbi(value, TWI_LCD_RW);
	
	sendPulse(value);
	Wire.endTransmission();
}

void twiLCD::sendPulse(int value)
{
	cbi(value, TWI_LCD_ENABLE);
	writeToPCF(value);
	
	sbi(value, TWI_LCD_ENABLE);
	writeToPCF(value);
	
	cbi(value, TWI_LCD_ENABLE);
	writeToPCF(value);
}

void twiLCD::writeToPCF(int value)
{
#if defined(TWI_LCD_CTRL) && !defined(TWI_LCD_BL_PWM)
	if (backlightStatus)
		sbi(value, TWI_LCD_BACKLIGHT);
	else
		cbi(value, TWI_LCD_BACKLIGHT);
	
	Wire.send(value);
#else
	Wire.send(value);
#endif
}

void twiLCD::clearScreen(void)
{
	writeCommand(LCD_CLEAR);
	delay(100);
	
#if defined(__AVR_ATmega168__) && !defined(TWI_LCD_SMALL)
	currentLine = 1;
#endif
	
#ifdef LCD_USE_CLRSCREEN_CALLBACK
	if (twiLCDcallbackFunc[0]) twiLCDcallbackFunc[0]();
#endif
}

void twiLCD::printString_P(const char *data)
{
    int ch;
	
    for (;;) {
        ch = pgm_read_byte( data++ );
        if ( !ch ) return;
		writeData(ch);
    }
}

#if defined(__AVR_ATmega168__) && !defined(TWI_LCD_SMALL)
#ifdef TWI_LCD_USE_TIMEOUT
boolean twiLCD::checkTimeout(void)
{
	if (displayStatus && millis() - previousMillis > TWI_LCD_TIMEOUT) {
		turnOff();
		return true;
    }

	return false;
}
#endif

#ifdef TWI_LCD_CTRL
#ifdef TWI_LCD_BL_PWM
void twiLCD::backlightOn(void)
{
	digitalWrite(TWI_LCD_BACKLIGHT, HIGH);
}

void twiLCD::backlightOn(uint8_t value)
{
	analogWrite(TWI_LCD_BACKLIGHT, value);
}

void twiLCD::backlightOff(void)
{
	digitalWrite(TWI_LCD_BACKLIGHT, LOW);
}
#else
#ifdef TWI_LCD_DPOT_CTRL
void twiLCD::backlightOn(void)
{
	DPOT.setWiper2(TWI_LCD_BL_LEVEL);
}

void twiLCD::backlightOn(uint8_t value)
{
	DPOT.setWiper2(value);
}

void twiLCD::backlightOff(void)
{
	DPOT.setWiper2(0);
}

void twiLCD::setBrightness(void)
{
	DPOT.setWiper1(TWI_LCD_DB_LEVEL);
}

void twiLCD::setBrightness(uint8_t value)
{
	DPOT.setWiper1(value);
}

#else
void twiLCD::backlightOn(void)
{
	int val = 0;
	backlightStatus	= 1;
	sbi(val, TWI_LCD_BACKLIGHT);
	
	Wire.beginTransmission(PCF8574_WADDR);
	Wire.send(val);
	Wire.endTransmission();
}

void twiLCD::backlightOff(void)
{
	int val = 0;
	backlightStatus	= 0;
	cbi(val, TWI_LCD_BACKLIGHT);
	
	Wire.beginTransmission(PCF8574_WADDR);
	Wire.send(val);
	Wire.endTransmission();
}
#endif
#endif
#endif

void twiLCD::turnOff(void)
{
	writeCommand(LCD_TURN_OFF);
#if defined(TWI_LCD_CTRL)
	backlightOff();
#ifdef TWI_LCD_DPOT_CTRL
	setBrightness(0);
#endif
#endif
	displayStatus = false;
}

/**
 * This function needs a rewrite
**/
void twiLCD::setCursor(int index)
{
	//0-79, index for one line display, 8 bit mode
	//0-39 and 64-103 for lines one and two of two line display, not implemented yet
	int cmd = 128+index;
	writeCommand(cmd);
}

/**
 * This function needs a rewrite
**/
void twiLCD::moveToXY(uint8_t row, uint8_t column)
{
	int position;
	
	//	Determine the new position
	position = (row * 20) + column;
	
	//	Send the correct commands to the command register of the LCD
	if(position < 20)
		writeCommand(0x80 | position);
	else if(position >= 20 && position < 40)
		writeCommand(0x80 | (position % 20 + 0x40));
	else if(position >= 41 && position < 60)
		writeCommand(0x80 | (position % 40 + 0x14));
	else if(position >= 20 && position < 40)
		writeCommand(0x80 | (position % 60 + 0x54));
}

uint8_t twiLCD::getCurrentLine(void)
{
	return currentLine;
}

void twiLCD::goToLine(uint8_t line)
{
	if (line > LCD_ROWS) return;
	moveToXY(line - 1, 0);
	currentLine = line;
}

void twiLCD::goToNextLine(void)
{
	if (currentLine+1 > LCD_ROWS) {
		goToLine(1);
	} else {
		goToLine(currentLine+1);
	}
}

void twiLCD::goHome(void)
{
	writeCommand(LCD_GO_HOME);	 // set cursor position to zero
	currentLine = 1;
}

void twiLCD::clearLine(void)
{
	int ii;
	moveToXY(currentLine-1, 0);
	
	for (ii=0;ii<LCD_COLUMNS;ii++)
	{
		printString(" ");
	}
	
	moveToXY(currentLine-1, 0);
}

void twiLCD::shiftDisplayLeft(void)
{ 
	writeCommand(LCD_SHIFT_LEFT);
}

void twiLCD::shiftDisplayRight(void)
{
	writeCommand(LCD_SHIFT_RIGHT);
}

bool twiLCD::getCurrentStatus(void)
{
	return displayStatus;
}

void twiLCD::printInteger(uint16_t integer, bool leadingZero)
{	
	uint8_t thousands = integer / 1000;
	uint8_t hundreds = (integer - thousands*1000) / 100;
	uint8_t tens = (integer - thousands*1000 - hundreds*100 ) / 10;
	writeData(tens + 0x30);
	
	uint8_t ones = (integer - thousands*1000 - hundreds*100 - tens*10);
	writeData(ones + 0x30);
}

void twiLCD::printInteger(int16_t integer)
{
	if (integer < 0)  {
		printString("-");
		integer	= 0 - integer;
	}
	
	//	Break down the original number into the thousands, hundreds, tens,
	//	and ones places and then immediately write that value to the LCD
	uint8_t thousands = integer / 1000;
	if (thousands > 0) writeData(thousands + 0x30);
	
	uint8_t hundreds = (integer - thousands*1000) / 100;
	if (hundreds > 0 || thousands > 0)
		writeData(hundreds + 0x30);
	
	uint8_t tens = (integer - thousands*1000 - hundreds*100 ) / 10;
	if (tens || hundreds > 0 || thousands > 0)
		writeData(tens + 0x30);
	
	uint8_t ones = (integer - thousands*1000 - hundreds*100 - tens*10);
	writeData(ones + 0x30);
}

#endif

#ifdef LCD_USE_CLRSCREEN_CALLBACK
void twiLCD::clrsSetCallback(void (*userFunc)(void))
{
	twiLCDcallbackFunc[0] = userFunc;
}
#endif