#include <pic18.h>
#include <stdio.h>
#include <htc.h>
#include <string.h>
#include <stdlib.h>

#include "lcd.h"
#include "Delay.h"
// Delay.h is included inside lcd.c

#define BUFFER 128
#define PWRFAIL RB1
#define FIREDET RB2
#define FEEDING RB3
#define EMPTYTANK RB4


unsigned char global_Pot_Hi, global_Pot_Lo;
unsigned char global_serial_send[BUFFER], global_serial_recieve_buffer[BUFFER];
bit global_recieve_done = 0, global_interval_changed = 0;
unsigned int global_serial_byte_counter = 0, global_sms_counter = 1, global_time_counter = 0,  global_time_counter_image = 0;
unsigned int global_emergency_counter = 600, global_time_interval = 3600;
unsigned char global_temp = 0;

unsigned int global_temp_update_display = 0;

unsigned char global_message_buffer1[BUFFER];
unsigned char global_message_buffer2[BUFFER];
unsigned char global_message_buffer_length1;
unsigned char global_message_buffer_length2;

unsigned char global_lcd_buf[16];

unsigned int global_imei_tversum;

unsigned char global_cell_nr[15] = ""; // = "21681784";
bit global_modem_init = 0;
bit global_has_imei = 0;

unsigned char global_sms_recieve_number[3];

__EEPROM_DATA( 60, 0, 1, 8, '2', '1', '6', '8');
__EEPROM_DATA( '1', '7', '8', '4',0,0,0,0);


void serial_recieved(void);
void serial_send(void);
void update_lcd(void);
void convertTemp(void);
void timer1_interrupt(void);
void on_recieve(void);
void on_initial_recieve(void);
void sms_recieved(void);
void send_sms(const unsigned char* payload);
void eeprom_writer(void);


void reset_recieve_buffer(void)
{
	global_recieve_done = 0;
	
	global_message_buffer_length1 = 0;
	//global_message_buffer1[0] = 0;	
	global_message_buffer_length2 = 0;
	//global_message_buffer2[0] = 0;	
	
	memset(global_message_buffer1, 0, BUFFER);
	memset(global_message_buffer2, 0, BUFFER);
}	
//////////  INITS  //////////
void pic18_io_init(void)
{
	TRISA0	= 1;	// analog input
	TRISA5	= 0;	// Output
	TRISB1	= 1;	// TRISB1-4 Digital input
	TRISB2	= 1;
	TRISB3	= 1;
	TRISB4	= 1;
}



void ad_init(void) // Nicked from H7
{
	// AD Conversion clock
	ADCS0 = 0;
	ADCS1 = 0;
	ADCS2 = 0;

	//Select AN0/RA0 for AD source
		// In this (000) setup, it's only RA0/AN0 that does ad convertion.
	CHS0=0;
	CHS1=0;
	CHS2=0;
	
	//Only AN0 is selected for AD and with Vdd/Vss as limits
	PCFG0=0;
	PCFG1=1;
	PCFG2=1;
	PCFG3=1;
	
	//Reset the A/D result registers
	ADRESH = 0;
	ADRESL = 0;
	
	//Result is right justified
	ADFM=1; 
	
	//Fire up for A/D converter module
	ADON=1;
}



void interrupt_init(void)
{
	// Assumes that all interrupts default is 0
	PEIE	= 1;
	GIE		= 1;
	RCIE	= 1;	// Recieve interrupt enable.
	IPEN	= 0;	// Nfo interrupt priority
	TXIE	= 0;	// Serial interrupt enabled
	TMR1IE	= 1;	// Enables timer 1
}	



void timer_init(void)
{
	TMR1CS = 1; //use external clock
	
	T1CKPS1 = 1; //1:8 prescale
	T1CKPS0 = 1;
	
	TMR1H = 0xEF;
	TMR1L = 0xFF;

	T1OSCEN = 1; //enable oscillator circuit	
	RD16 = 0; //normal 8 bit writes
	TMR1ON = 1;
}
	
void rs232_init(void)
{
	SPEN	= 0;	// Serial Port Enable Bit... 0 = disabled
	TRISC6	= 0;	
	TRISC7	= 1;

	SPBRG	= 207;	// 1200 baud rate... 25 = 9600
					// x = (Fosc / (16*[baud rate]) )-1
	TXSTA	= 0x24;	// Enables BRGH and TXEN inthe TXSTA register
	RCSTA	= 0x90;	// 0x90 enables SPEN and CREN in the RCSTA register
}

void sms_init(void)
{
	int i;
	char buf[2];
	
	while ( strstr(global_message_buffer1,"+WIND: 7") == 0 && global_time_counter < 10 ) ;	// Waiting for the modem to be ready

	reset_recieve_buffer();
	sprintf(global_serial_send,"at+cgsn\r");
	serial_send();
	
	while (global_has_imei == 0)
	{
		if (strstr(global_message_buffer1,"OK") != 0)
		{
			global_imei_tversum = 0;
			for (i=0; i<15; ++i)
			{
				buf[0] = global_message_buffer2[i];
				buf[1] = 0;
				global_imei_tversum += atoi(buf);
			}
			
			global_has_imei = 1;
		}
	}

	sprintf(global_serial_send,"%s", "at+cpin?\r");
	serial_send();
	DelayMs(100);		// Delay to give the modem a chance to answer.
	
	if (strstr(global_message_buffer1, "+CPIN: SIM PIN") != 0)
	{
		sprintf(global_serial_send,"%s", "at+cpin=8043\r");
		serial_send();
		
		while(global_modem_init == 0)
		{
			on_initial_recieve();
		}
	}
	reset_recieve_buffer();
	sprintf(global_serial_send, "at+cmgd=1,4\r");
	serial_send();
	while ( strstr(global_message_buffer1,"OK") == 0) ;
}

void serial_send(void)
{
	int i;
	char data_byte;
	for(i = 0; i < BUFFER; i++)
	{
		data_byte = global_serial_send[i];
		if( data_byte == '\r')
			i = (BUFFER - 1);
		TXREG = data_byte;
		while(TRMT==0) ;
		DelayMs(10);
	}
	DelayMs(150);
	global_serial_send[0] = 0;
	DelayMs(150);
}

void on_initial_recieve(void)
{
	char imei[16];
	char* ptr;
	char i;
	char buf[2];
	
	if (strstr(global_serial_recieve_buffer,"+WIND: 11") != 0)
	{
		global_modem_init = 1;

		ptr = strstr(global_serial_recieve_buffer,"cgsn");
		ptr +=4;
		strncpy(imei, ptr,15);
		imei[15] = 0;
		
		reset_recieve_buffer();
	}
}

//////////  INTERRUPT HANDLER  //////////
void interrupt interrupt_handler(void)
{
	// Finds out what interrupt have been trigged, and starts the respective function.
	if(RCIF == 1)			// Serial recieve interrupt
	{
		serial_recieved();
		RCIF = 0;
	}
	
	if(TMR1IF == 1)			// timer1 interrupt trigger.
	{
		timer1_interrupt();
		TMR1IF = 0;
	}
}		

//////////  INTERRUPT TRIGGED //////////
void serial_recieved(void) 
{
	char data_byte;
	
	data_byte = RCREG;
	
	if (data_byte == '\n')		// Cant be bothered to do anyting if the byte is a '\n'.
		return;
		
	if (global_serial_byte_counter == 0 && data_byte == '\r')	// don't care about '\r', if it's the first byte we recieve.
		return;


	if ( global_serial_byte_counter < BUFFER) //Prevent buffer overrun
		global_serial_recieve_buffer[ global_serial_byte_counter++ ] = data_byte;	// fills the data_byte into our buffer.
	else
	{
		global_serial_recieve_buffer[0] = 0;
		global_serial_byte_counter = 0;
		return;
	}
	
	
	if (data_byte == '\r')	// when we meet a '\r', the transmission is done, and we fill the constxt of 
							// global_message_buffer1 into global_message_buffer2 our main buffer into
							// global_message_buffer2, and the same with our recieve buffer, global_serial_recieve_buffer
							// into global_message_buffer1.
	{
		global_recieve_done = 1; // indicates the recieve transmission is done.
		global_serial_recieve_buffer[global_serial_byte_counter] = 0; //zero terminate
		
		// global_message_buffer1 -> global_message_buffer2
		strcpy(global_message_buffer2, global_message_buffer1);
		global_message_buffer_length2 = global_message_buffer_length1;
		
		// global_serial_recieve_buffer -> global_message_buffer1
		strcpy(global_message_buffer1, global_serial_recieve_buffer);
		global_message_buffer_length1 = global_serial_byte_counter;
		
		
		global_serial_byte_counter = 0;
	}	
}

void timer1_interrupt(void)
{
	TMR1H = 0xEF;
	TMR1L = 0xFF;
	global_time_counter++;
	global_emergency_counter++;
	RA1 = !RA1;
}
//////////  ORDENARY FUNKTIONS  //////////
void update_lcd(void)
{
	if(global_temp_update_display != global_time_counter)
	{
	//	lcd_clear();
		lcd_goto(0x00);
	
		sprintf(global_lcd_buf, "Temp: %3d", global_temp);
		lcd_puts(global_lcd_buf);
		global_temp_update_display = global_time_counter;
	}

}
	
void send_update(void)
{
	char update[40];
	sprintf(update, "%d:%d:%d:%d:%d:%d", global_sms_counter, global_temp, FIREDET, EMPTYTANK, FEEDING, PWRFAIL);
	send_sms(update);

	global_sms_counter++;
}	

void send_sms(const unsigned char* payload)
{
	sprintf(global_serial_send, "at+cmgs=\"%s\"\r", global_cell_nr);
	serial_send();
	sprintf(global_serial_send, "%s%c", payload, 0x1A);
	serial_send();
	DelayMs(150);
	if(global_sms_counter % 4 == 0)
	{
		eeprom_writer();
		sprintf(global_serial_send, "at+cmgd=1,3\r");
		serial_send();
		while ( strstr(global_message_buffer1,"OK") == 0) ;
	}
}	

void convert_temp()
{
	short adVal;
	adVal = (global_Pot_Hi << 8) | global_Pot_Lo;
	if( adVal >=840 )
		global_temp = 100;
	else
		global_temp = (unsigned char) (adVal / 8.3886);
}



void eeprom_writer(void)
{
	char len,i;
	
	len = strlen(global_cell_nr);
	eeprom_write(0, (global_time_interval/60));
	eeprom_write(1, global_sms_counter>>8);
	eeprom_write(2, global_sms_counter);
	eeprom_write(3, len);
	
	for (i=0; i<len; ++i)
	{
		eeprom_write(i+4, global_cell_nr[i] );
	}
}

void eeprom_reader(void)
{
	char len,i;
	
	global_time_interval = eeprom_read(0);
	global_time_interval *= 60;
	global_sms_counter = (eeprom_read(1)<<8) | eeprom_read(2);
	len = eeprom_read(3);
	
	for (i=0; i<len; ++i)
	{
		global_cell_nr[i] = eeprom_read(i+4);
	}
	
	global_cell_nr[i] = 0; //zero terminated!
}	


void on_recieve(void)
{
	char tmp[3];
	char* ptr;
	tmp[0]=0;
		
	if (global_recieve_done == 0 || global_message_buffer_length1 == 0)
		return;

	if (strstr(global_message_buffer1,"CMTI") != 0) // here we handles a incomming SMS
	{
		ptr = strstr(global_message_buffer1,",");	// finds the point just before the nr. of the SMS.
		strcat(tmp,ptr+1);							// puts that number in tmp
		global_sms_recieve_number[0] = 0;			// wanna be sure that we write the new number from global_sms_recieve_number[0]
		strcat(global_sms_recieve_number, tmp);		// puts the sms number into the global variable.
		sms_recieved();
	}	
	reset_recieve_buffer();
}

void sms_recieved(void)
{
	char buf[4];
	char i,imei;
	char pos;
	
	sprintf(global_serial_send, "AT+CMGR=%s\r", global_sms_recieve_number);	// formates the variable that sends commands to the SMS modem.
	serial_send();		// Sends the command.
	
	while(strstr(global_message_buffer1, "OK")  == 0)	// stays here until we recieve a "OK" from the modem.
		DelayMs(1);

	DelayUs(10);
	
	for (i=0; global_message_buffer2[i] != ':' && global_message_buffer2[i] != 0; ++i)
	{
		buf[i] = global_message_buffer2[i];
	}
	
	buf[i] = 0;
	imei = atoi(buf);
	
	if (imei == global_imei_tversum)
	{
		i++; //spring over ':'
		pos = 0;
		for ( ; global_message_buffer2[i] != ':'; ++i, ++pos)
		{
			global_cell_nr[pos] = global_message_buffer2[i];
		}
		global_cell_nr[pos] = 0; //zero terminator
		
		i++; //spring over ':'
		pos=0;
		for ( ; global_message_buffer2[i] ; ++i,++pos)
		{
			buf[pos] = global_message_buffer2[i];
		}
		buf[pos]=0;
		
		global_time_interval = atoi(buf);
		global_time_interval *= 60;
		eeprom_writer();			// writes the new cell nr. and time interval to the eeprom.
		send_sms("conf ok");
	}
	

}

void Delay(int time)
{
	int wanted = (global_time_counter + time) % global_time_interval;
	
	while (global_time_counter < wanted) ;
}

void main()
{
////////////////////
// Running Init's //

	// Running init for various components.
	pic18_io_init();
	RA5 = 1;			// Indicates that the board is running inits.
	
	rs232_init();
	ad_init();
	lcd_init(0);
	lcd_clear();
	lcd_home();
	interrupt_init();
	timer_init();
	sms_init();
	eeprom_reader();
///////////////
// Main loop //

	DelayMs(50);
	reset_recieve_buffer();

	RA5 = 0;			// Inits are done, and RA1 will now work as a error notifier.

	while(1)
	{
	// If there happends to be a critical state on the system, we send a sms.
		if( (global_temp >= 90 || PWRFAIL == 1 || FIREDET == 0 || FEEDING ==1 ) && global_emergency_counter >= 600 )
		{
			send_update();
			global_emergency_counter = 0;
		}
		
	// Every X sec. a status sms is send.
		if(global_time_counter >= global_time_interval)
		{
			send_update();
			global_time_counter = 0;
		}
	// To avoid buffer overrun.
		if( global_emergency_counter > 7200 )
			global_emergency_counter = 600;

	// Checks if there has been recieved a config sms.
		if(global_interval_changed )
		{
			eeprom_writer();
			global_interval_changed = 0;
		}
	// Checking if A/D convertion is done, and save the data in global_Pot_??
		if(GODONE==0)
		{
			global_Pot_Hi = ADRESH;
			global_Pot_Lo = ADRESL;
			convert_temp();
			update_lcd();
			GODONE = 1;
		}
	// Handels the recieve sms'es.
		on_recieve();
	}
}