#ifndef twiLCD_H
#define twiLCD_H
	#include "../global.h"
	
	#include "../configs/LCD/lcd.h"
	#include "../configs/twiLCD/twiLCD.h"
	
#ifndef PCF8574_A0
	#define PCF8574_A0			0
#endif
#ifndef PCF8574_A1
	#define PCF8574_A1			0
#endif
#ifndef PCF8574_A2
	#define PCF8574_A2			0
#endif
	
	#define PCF8574_BASE_ADDR	B00100000
	#define PCF8574_WADDR		PCF8574_BASE_ADDR | (PCF8574_A0 * B00000001) | (PCF8574_A1 * B00000010) | (PCF8574_A2 * B00000100)
	#define PCF8574_RADDR		PCF8574_WADDR | 0x01
	
	#define TWI_LCD_RS			0	/* RS pin */
	#define TWI_LCD_RW			1	/* RW pin */
	#define TWI_LCD_ENABLE		2	/* Enable pin */
#ifdef TWI_LCD_CTRL
#ifdef TWI_LCD_BL_PWM
	#define TWI_LCD_BACKLIGHT	9	/* This is an Arduino pin number! */
#else
	#define TWI_LCD_BACKLIGHT	3	/* Backlight pin */
#endif
#endif
	
	#define TWI_LCD_CONTROL		B00000111	/* Mask for the 3 control bits (E, RS, RW) */
	#define TWI_LCD_DATA		B11110000	/* Mask for the 4 bit word */
	#define TWI_LCD_DATAH		B11110000
	#define TWI_LCD_DATAL		B00001111
	#define TWI_LCD_BUSY		B00001000
	
#ifndef printString
	#define printString(str)	printString_P(PSTR(str))
#endif
	
#ifdef LCD_USE_CLRSCREEN_CALLBACK
	volatile static voidFuncPtr twiLCDcallbackFunc[1];
#endif
	
	class twiLCD {
		public:
			/**
			 * Constructor: initializes this class
			**/
			twiLCD();
			
			/**
			 * LCD Initilization method
			**/
			void	Init();
			
			/**
			 * writeData: write a byte of data to the LCD
			 * @param: value: the byte to write
			**/
			void	writeData(uint8_t);
			
			/**
			 * clearScreen: clears the LCD and resets the cursor position to 0,0
			**/
			void	clearScreen(void);
			
			/**
			 * printString_P: prints a program string to the LCD
			 * 	To call this function, use the LCD.printString() macro!
			**/
			void	printString_P(const char *);
			
		#ifdef LCD_USE_CLRSCREEN_CALLBACK
			void	clrsSetCallback(void (*)(void));
		#endif
	/**
	 * These function are only available on the mega168 for space reasons
	**/
	#if defined(__AVR_ATmega168__) && !defined(TWI_LCD_SMALL)
		
		/**
		 * Methods for dealing with LCD timeout
		 * Returns true if the time is expired
		**/
		#ifdef TWI_LCD_USE_TIMEOUT
			boolean	checkTimeout(void);
		#endif
		
		/**
		 * Backlight control functions
		 * Optionally enabled above
		**/
		#ifdef TWI_LCD_CTRL
			/**
			 * backlightOn: Turn on the backlight at full brightness
			**/
			void	backlightOn(void);
			
			/**
			 * backlightOff: turn off the LCD backlight
			**/
			void	backlightOff(void);
			
			// PWM Backlight Control
			#if defined(TWI_LCD_BL_PWM) || defined(TWI_LCD_DPOT_CTRL)
				/**
				 * backlightOn: turns on the backlight with a specific brightness
				**/
				void backlightOn(uint8_t);
			#endif
			
			#ifdef TWI_LCD_DPOT_CTRL
				/**
				 * setBrightness: sets the brightness level using a digital pot
				 * If no param is passed TWI_LCD_DB_LEVEL is used
				**/
				void setBrightness(void);
				void setBrightness(uint8_t);
			#endif
		#endif
		
			/**
			 * setCursor: set cursor a position "index"
			**/
			void setCursor(int);
			
			/**
			 * moveToXY: moves the cursor to position (row,column)
			**/
			void moveToXY(uint8_t, uint8_t);
			
			/**
			 * Turn off the LCD (will turn off the backlight if control is enabled)
			**/
			void turnOff(void);
			
			/**
			 * goToLine: Allows to move at the beginning of a specific line
			**/
			void goToLine(uint8_t);
			
			/**
			 * goToNextLine: goes to the next line, wraps arround at the end
			**/
			void goToNextLine(void);
			
			/**
			 * goHome: goes to position (0,0)
			**/
			void goHome(void);
			
			/**
			 * clearLine: clears the current line
			**/
			void clearLine(void);
			
			/**
			 * shiftDisplayLeft: shift all lines of the display one position to the left
			**/
			void shiftDisplayLeft(void);
			
			/**
			 * shiftDisplayRight: shift all lines of the display one position to the right
			**/
			void shiftDisplayRight(void);
			
			/**
			 * getCurrentLine: returns the current line
			**/
			uint8_t getCurrentLine(void);
			
			/**
			 * getCurrentStatus: returns whether the display is on or off
			**/
			bool getCurrentStatus(void);
			
			/**
			 * printInteger: writes an interger as text on the lcd
			 * The second version is only good for intergers < 99 and will add a leading zero
			**/
			void printInteger(int16_t);
			void printInteger(uint16_t integer, bool leadingZero);
	#endif
		private:
	#if defined(__AVR_ATmega168__) && !defined(TWI_LCD_SMALL)
		#ifdef TWI_LCD_USE_TIMEOUT
			unsigned long	previousMillis;
		#endif
		
		#if defined(TWI_LCD_CTRL) && !defined(TWI_LCD_BL_PWM)
			/**
			 * backlightStatus: used to keep track of the backlight status
			**/
			uint8_t		backlightStatus;
		#endif
			
			/**
			 * currentLine: keeps track of the current line
			**/
			uint8_t		currentLine;
			
			/**
			 * displayStatus: keeps track of whether the display is on or off
			**/
			bool		displayStatus;
	#endif
			/**
			 * sendPulse: sends a byte of data with the appropiate Enable pulse
			**/
			void		sendPulse(int);
			
			/**
			 * writeToPCF: writes a new byte of data using twi
			 * 	This function is used to preserve some data through writes
			 * 	such as when bit3 of the expander is used to control the backlight
			**/
			void		writeToPCF(int);
			
			/**
			 * writeCommand: Writes an LCD command
			 * @param: value: the value to write
			**/
			void		writeCommand(uint8_t value);
			
			/**
			 * checkLCDBusy: reads the busy state bit from the LCD
			**/
			boolean		checkLCDBusy(void);
	};

	/**
	 * Define the object's name
	**/
	extern twiLCD LCD;

#endif