#include <Wire.h>
// #include <LiquidCrystal_I2C.h>
// #include <LcdBarGraphRobojax.h>

#ifndef FDB_LIQUID_CRYSTAL_I2C_H
#define FDB_LIQUID_CRYSTAL_I2C_H

#include <inttypes.h>
#include <Print.h>

// commands
#define LCD_CLEARDISPLAY 0x01
#define LCD_RETURNHOME 0x02
#define LCD_ENTRYMODESET 0x04
#define LCD_DISPLAYCONTROL 0x08
#define LCD_CURSORSHIFT 0x10
#define LCD_FUNCTIONSET 0x20
#define LCD_SETCGRAMADDR 0x40
#define LCD_SETDDRAMADDR 0x80

// flags for display entry mode
#define LCD_ENTRYRIGHT 0x00
#define LCD_ENTRYLEFT 0x02
#define LCD_ENTRYSHIFTINCREMENT 0x01
#define LCD_ENTRYSHIFTDECREMENT 0x00

// flags for display on/off control
#define LCD_DISPLAYON 0x04
#define LCD_DISPLAYOFF 0x00
#define LCD_CURSORON 0x02
#define LCD_CURSOROFF 0x00
#define LCD_BLINKON 0x01
#define LCD_BLINKOFF 0x00

// flags for display/cursor shift
#define LCD_DISPLAYMOVE 0x08
#define LCD_CURSORMOVE 0x00
#define LCD_MOVERIGHT 0x04
#define LCD_MOVELEFT 0x00

// flags for function set
#define LCD_8BITMODE 0x10
#define LCD_4BITMODE 0x00
#define LCD_2LINE 0x08
#define LCD_1LINE 0x00
#define LCD_5x10DOTS 0x04
#define LCD_5x8DOTS 0x00

// flags for backlight control
#define LCD_BACKLIGHT 0x08
#define LCD_NOBACKLIGHT 0x00

#define En B00000100  // Enable bit
#define Rw B00000010  // Read/Write bit
#define Rs B00000001  // Register select bit

/**
 * This is the driver for the Liquid Crystal LCD displays that use the I2C bus.
 *
 * After creating an instance of this class, first call begin() before anything else.
 * The backlight is on by default, since that is the most likely operating mode in
 * most cases.
 */
class LiquidCrystal_I2C : public Print {
public:
	/**
	 * Constructor
	 *
	 * @param lcd_addr	I2C slave address of the LCD display. Most likely printed on the
	 *					LCD circuit board, or look in the supplied LCD documentation.
	 * @param lcd_cols	Number of columns your LCD display has.
	 * @param lcd_rows	Number of rows your LCD display has.
	 * @param charsize	The size in dots that the display has, use LCD_5x10DOTS or LCD_5x8DOTS.
	 */
	LiquidCrystal_I2C(uint8_t lcd_addr, uint8_t lcd_cols, uint8_t lcd_rows, uint8_t charsize = LCD_5x8DOTS);

	/**
	 * Set the LCD display in the correct begin state, must be called before anything else is done.
	 */
	void begin();

	 /**
	  * Remove all the characters currently shown. Next print/write operation will start
	  * from the first position on LCD display.
	  */
	void clear();

	/**
	 * Next print/write operation will will start from the first position on the LCD display.
	 */
	void home();

	 /**
	  * Do not show any characters on the LCD display. Backlight state will remain unchanged.
	  * Also all characters written on the display will return, when the display in enabled again.
	  */
	void noDisplay();

	/**
	 * Show the characters on the LCD display, this is the normal behaviour. This method should
	 * only be used after noDisplay() has been used.
	 */
	void display();

	/**
	 * Do not blink the cursor indicator.
	 */
	void noBlink();

	/**
	 * Start blinking the cursor indicator.
	 */
	void blink();

	/**
	 * Do not show a cursor indicator.
	 */
	void noCursor();

	/**
 	 * Show a cursor indicator, cursor can blink on not blink. Use the
	 * methods blink() and noBlink() for changing cursor blink.
	 */
	void cursor();

	void scrollDisplayLeft();
	void scrollDisplayRight();
	void printLeft();
	void printRight();
	void leftToRight();
	void rightToLeft();
	void shiftIncrement();
	void shiftDecrement();
	void noBacklight();
	void backlight();
	bool getBacklight();
	void autoscroll();
	void noAutoscroll();
	void createChar(uint8_t, uint8_t[]);
	void setCursor(uint8_t, uint8_t);
	virtual size_t write(uint8_t);
	void command(uint8_t);

	inline void blink_on() { blink(); }
	inline void blink_off() { noBlink(); }
	inline void cursor_on() { cursor(); }
	inline void cursor_off() { noCursor(); }

// Compatibility API function aliases
	void setBacklight(uint8_t new_val);				// alias for backlight() and nobacklight()
	void load_custom_character(uint8_t char_num, uint8_t *rows);	// alias for createChar()
	void printstr(const char[]);

private:
	void send(uint8_t, uint8_t);
	void write4bits(uint8_t);
	void expanderWrite(uint8_t);
	void pulseEnable(uint8_t);
	uint8_t _addr;
	uint8_t _displayfunction;
	uint8_t _displaycontrol;
	uint8_t _displaymode;
	uint8_t _cols;
	uint8_t _rows;
	uint8_t _charsize;
	uint8_t _backlightval;
};

#endif // FDB_LIQUID_CRYSTAL_I2C_H

// #include "LiquidCrystal_I2C.h"
#include <inttypes.h>
#include <Arduino.h>
#include <Wire.h>

// When the display powers up, it is configured as follows:
//
// 1. Display clear
// 2. Function set:
//    DL = 1; 8-bit interface data
//    N = 0; 1-line display
//    F = 0; 5x8 dot character font
// 3. Display on/off control:
//    D = 0; Display off
//    C = 0; Cursor off
//    B = 0; Blinking off
// 4. Entry mode set:
//    I/D = 1; Increment by 1
//    S = 0; No shift
//
// Note, however, that resetting the Arduino doesn't reset the LCD, so we
// can't assume that its in that state when a sketch starts (and the
// LiquidCrystal constructor is called).

LiquidCrystal_I2C::LiquidCrystal_I2C(uint8_t lcd_addr, uint8_t lcd_cols, uint8_t lcd_rows, uint8_t charsize)
{
	_addr = lcd_addr;
	_cols = lcd_cols;
	_rows = lcd_rows;
	_charsize = charsize;
	_backlightval = LCD_BACKLIGHT;
}

void LiquidCrystal_I2C::begin() {
	Wire.begin();
	_displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_5x8DOTS;

	if (_rows > 1) {
		_displayfunction |= LCD_2LINE;
	}

	// for some 1 line displays you can select a 10 pixel high font
	if ((_charsize != 0) && (_rows == 1)) {
		_displayfunction |= LCD_5x10DOTS;
	}

	// SEE PAGE 45/46 FOR INITIALIZATION SPECIFICATION!
	// according to datasheet, we need at least 40ms after power rises above 2.7V
	// before sending commands. Arduino can turn on way befer 4.5V so we'll wait 50
	delay(50);

	// Now we pull both RS and R/W low to begin commands
	expanderWrite(_backlightval);	// reset expanderand turn backlight off (Bit 8 =1)
	delay(1000);

	//put the LCD into 4 bit mode
	// this is according to the hitachi HD44780 datasheet
	// figure 24, pg 46

	// we start in 8bit mode, try to set 4 bit mode
	write4bits(0x03 << 4);
	delayMicroseconds(4500); // wait min 4.1ms

	// second try
	write4bits(0x03 << 4);
	delayMicroseconds(4500); // wait min 4.1ms

	// third go!
	write4bits(0x03 << 4);
	delayMicroseconds(150);

	// finally, set to 4-bit interface
	write4bits(0x02 << 4);

	// set # lines, font size, etc.
	command(LCD_FUNCTIONSET | _displayfunction);

	// turn the display on with no cursor or blinking default
	_displaycontrol = LCD_DISPLAYON | LCD_CURSOROFF | LCD_BLINKOFF;
	display();

	// clear it off
	clear();

	// Initialize to default text direction (for roman languages)
	_displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT;

	// set the entry mode
	command(LCD_ENTRYMODESET | _displaymode);

	home();
}

/********** high level commands, for the user! */
void LiquidCrystal_I2C::clear(){
	command(LCD_CLEARDISPLAY);// clear display, set cursor position to zero
	delayMicroseconds(2000);  // this command takes a long time!
}

void LiquidCrystal_I2C::home(){
	command(LCD_RETURNHOME);  // set cursor position to zero
	delayMicroseconds(2000);  // this command takes a long time!
}

void LiquidCrystal_I2C::setCursor(uint8_t col, uint8_t row){
	int row_offsets[] = { 0x00, 0x40, 0x14, 0x54 };
	if (row > _rows) {
		row = _rows-1;    // we count rows starting w/0
	}
	command(LCD_SETDDRAMADDR | (col + row_offsets[row]));
}

// Turn the display on/off (quickly)
void LiquidCrystal_I2C::noDisplay() {
	_displaycontrol &= ~LCD_DISPLAYON;
	command(LCD_DISPLAYCONTROL | _displaycontrol);
}
void LiquidCrystal_I2C::display() {
	_displaycontrol |= LCD_DISPLAYON;
	command(LCD_DISPLAYCONTROL | _displaycontrol);
}

// Turns the underline cursor on/off
void LiquidCrystal_I2C::noCursor() {
	_displaycontrol &= ~LCD_CURSORON;
	command(LCD_DISPLAYCONTROL | _displaycontrol);
}
void LiquidCrystal_I2C::cursor() {
	_displaycontrol |= LCD_CURSORON;
	command(LCD_DISPLAYCONTROL | _displaycontrol);
}

// Turn on and off the blinking cursor
void LiquidCrystal_I2C::noBlink() {
	_displaycontrol &= ~LCD_BLINKON;
	command(LCD_DISPLAYCONTROL | _displaycontrol);
}
void LiquidCrystal_I2C::blink() {
	_displaycontrol |= LCD_BLINKON;
	command(LCD_DISPLAYCONTROL | _displaycontrol);
}

// These commands scroll the display without changing the RAM
void LiquidCrystal_I2C::scrollDisplayLeft(void) {
	command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVELEFT);
}
void LiquidCrystal_I2C::scrollDisplayRight(void) {
	command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVERIGHT);
}

// This is for text that flows Left to Right
void LiquidCrystal_I2C::leftToRight(void) {
	_displaymode |= LCD_ENTRYLEFT;
	command(LCD_ENTRYMODESET | _displaymode);
}

// This is for text that flows Right to Left
void LiquidCrystal_I2C::rightToLeft(void) {
	_displaymode &= ~LCD_ENTRYLEFT;
	command(LCD_ENTRYMODESET | _displaymode);
}

// This will 'right justify' text from the cursor
void LiquidCrystal_I2C::autoscroll(void) {
	_displaymode |= LCD_ENTRYSHIFTINCREMENT;
	command(LCD_ENTRYMODESET | _displaymode);
}

// This will 'left justify' text from the cursor
void LiquidCrystal_I2C::noAutoscroll(void) {
	_displaymode &= ~LCD_ENTRYSHIFTINCREMENT;
	command(LCD_ENTRYMODESET | _displaymode);
}

// Allows us to fill the first 8 CGRAM locations
// with custom characters
void LiquidCrystal_I2C::createChar(uint8_t location, uint8_t charmap[]) {
	location &= 0x7; // we only have 8 locations 0-7
	command(LCD_SETCGRAMADDR | (location << 3));
	for (int i=0; i<8; i++) {
		write(charmap[i]);
	}
}

// Turn the (optional) backlight off/on
void LiquidCrystal_I2C::noBacklight(void) {
	_backlightval=LCD_NOBACKLIGHT;
	expanderWrite(0);
}

void LiquidCrystal_I2C::backlight(void) {
	_backlightval=LCD_BACKLIGHT;
	expanderWrite(0);
}
bool LiquidCrystal_I2C::getBacklight() {
  return _backlightval == LCD_BACKLIGHT;
}


/*********** mid level commands, for sending data/cmds */

inline void LiquidCrystal_I2C::command(uint8_t value) {
	send(value, 0);
}

inline size_t LiquidCrystal_I2C::write(uint8_t value) {
	send(value, Rs);
	return 1;
}


/************ low level data pushing commands **********/

// write either command or data
void LiquidCrystal_I2C::send(uint8_t value, uint8_t mode) {
	uint8_t highnib=value&0xf0;
	uint8_t lownib=(value<<4)&0xf0;
	write4bits((highnib)|mode);
	write4bits((lownib)|mode);
}

void LiquidCrystal_I2C::write4bits(uint8_t value) {
	expanderWrite(value);
	pulseEnable(value);
}

void LiquidCrystal_I2C::expanderWrite(uint8_t _data){
	Wire.beginTransmission(_addr);
	Wire.write((int)(_data) | _backlightval);
	Wire.endTransmission();
}

void LiquidCrystal_I2C::pulseEnable(uint8_t _data){
	expanderWrite(_data | En);	// En high
	delayMicroseconds(1);		// enable pulse must be >450ns

	expanderWrite(_data & ~En);	// En low
	delayMicroseconds(50);		// commands need > 37us to settle
}

void LiquidCrystal_I2C::load_custom_character(uint8_t char_num, uint8_t *rows){
	createChar(char_num, rows);
}

void LiquidCrystal_I2C::setBacklight(uint8_t new_val){
	if (new_val) {
		backlight();		// turn backlight on
	} else {
		noBacklight();		// turn backlight off
	}
}

void LiquidCrystal_I2C::printstr(const char c[]){
	//This function is not identical to the function used for "real" I2C displays
	//it's here so the user sketch doesn't have to be changed
	print(c);
}

int offset = 20;
int Sensors_max = 2500;

byte lcdNumCols = 16; // -- number of columns in the LCD
byte lcdLine = 2; // -- number of line in the LCD
byte sensorPin = 0; // -- value for this example


LiquidCrystal_I2C lcd(0x27, 16, 2); // -- creating LCD instance
       
void setup(){
  // -- initializing the LCD
  lcd.begin();
  lcd.clear();
  lcd.print("Leitor Voltagem");
  lcd.setCursor (0,1); //  
  lcd.print("Quatro Celulas"); 
  delay(2000);
  lcd.clear();
}

void loop()
{
  int volt0 = analogRead(A0);
	int volt1 = analogRead(A1);
	int volt2 = analogRead(A2);
	int volt3 = analogRead(A3);

	// map 0-1023 to 0-2500 and add correction offset
  double voltage0 = map(volt0, 0, 1023, 0, Sensors_max) + offset;
	double voltage1 = map(volt1, 0, 1023, 0, Sensors_max) + offset;
	double voltage2 = map(volt2, 0, 1023, 0, Sensors_max) + offset;
	double voltage3 = map(volt3, 0, 1023, 0, Sensors_max) + offset;

  double voltage_0 = voltage0 / 100;
	double voltage_1 = voltage1 / 100;
	double voltage_2 = voltage2 / 100;
	double voltage_3 = voltage3 / 100;
  
  // -- do some delay: frequent draw may cause broken visualization
	lcd.setCursor (0, 0);
	lcd.print("A:");
	lcd.setCursor (2, 0);
  lcd.print(voltage_0);
	lcd.setCursor (6, 0);
	lcd.print("V");
	lcd.setCursor (9, 0);
	lcd.print("B:");
  lcd.setCursor (11, 0);
	lcd.print(voltage_1);  
  lcd.setCursor (15, 0);  
  lcd.print("V");

  lcd.setCursor (0, 1);
	lcd.print("C:");
	lcd.setCursor (2, 1);
  lcd.print(voltage_2);
	lcd.setCursor (6, 1);
	lcd.print("V");
  lcd.setCursor (9, 1);
	lcd.print("D:");
	lcd.setCursor (11, 1);
	lcd.print(voltage_3);  
  lcd.setCursor (15, 1);  
  lcd.print("V");   
 
  delay(100);
}