#include <avr/io.h>
#include <stdint.h>
#include <avr/eeprom.h>
#include <avr/interrupt.h>
#include <util/delay.h>
//#include <avr/sleep.h>


// Berechnungen für F_CPU == 16e6!
#define RC5TIME 1.778e-3 // 1.778msec
#define PULSE_MIN (uint8_t)(F_CPU / 2048 * RC5TIME * 0.4 +0.5)
#define PULSE_1_2 (uint8_t)(F_CPU / 2048 * RC5TIME * 0.8 +0.5)
#define PULSE_MAX (uint8_t)(F_CPU / 2048 * RC5TIME * 1.2 +0.5)

#define IR_IN PINB // Input Port
#define IR_PIN PB0 // Input Pin

#define SECTIME (uint16_t)(F_CPU / 2048 * 3) // 3 Sekunden
#define LEDTIME (uint16_t)(F_CPU / 2048 / 1000 * 50) // 50 msec

uint8_t rc5Bit; // bit value
uint8_t rc5Time; // Count Bit Time
uint16_t rc5Tmp; // Shift Bits in
volatile uint16_t rc5Data; // store result

uint16_t codes[15] EEMEM; // Codes im EEPROM
uint8_t sicherung; // Sicherungen für die ersten 4 Ausgänge
uint16_t seccounter; // Zählt TimerInterrupts für Sicherungen

void startAnimation();
void learnMode(uint8_t);
void normalMode();
void rc5();
void led(uint8_t);

// Timer Interrupt
ISR(TIMER0_OVF_vect){
    led(0);
    if(sicherung){ // Sicherung gesetzt?
        seccounter++;
        if(seccounter == SECTIME){ // Limit erreicht?
            sicherung = 0;
            seccounter = 0;
        }
    }    

    rc5();
}


// Main Programm
int main(){
	// Init Stuff
	DDRD  = 0xE3;
	PORTB = 0x1E;
	DDRC  = 0x3F;

	startAnimation();

    // Set Timer settings
    TCCR0 = (1 << CS02) | (1 << CS00);
    TIMSK = 1 << TOIE0;

	// What mode?
	if(MCUCSR & (1 << 1)){  // Externel Reset?
		// Ok, check whether or not dips are set
		uint8_t dip = 0;
		dip = PINB;
        dip >>= 1;
        dip = ~dip;
		dip &= 0xF;
		
		if(dip != 0){ 		// Learn!
			learnMode(dip);
		}
		else{				// Normal mode
			normalMode();
		}
	}
	else{					// Normal mode
		normalMode();
	} 
	
	return 0;
}

// Run trough Leds
void startAnimation(){
	PORTD |= 1 << 7;
	_delay_ms(50);
	PORTD  &= ~(1 << 7);
	PORTD |= 1 << 6;
	_delay_ms(50);
	PORTD  &= ~(1 << 6);
	PORTD |= 1 << 5;
	_delay_ms(50);
	PORTD  &= ~(1 << 5);
}

// Switching Leds on and automatic off
void led(uint8_t l){
    static uint16_t counter;

    switch(l){
        case 5:
            PORTD |= 1 << 5;
            counter = 0;
            break;
        case 6:
            PORTD |= 1 << 6;
            counter = 0;
            break;        
        case 7:
            PORTD |= 1 << 7;
            counter = 0;
            break;
        default:
            if(PORTD & ((1 << 5) | (1 << 6) | (1 << 7))){
                counter++;
                if(counter == LEDTIME){
                    PORTD &= ~((1 << 5) | (1 << 6) | (1 << 7));
                    counter = 0;
                }
            }
    }
}

// Learn Mode
// Waiting vor IR-signal and save it
// or delete all
void learnMode(uint8_t dip){
	uint16_t data;
    
    PORTD |= 1 << 7; // turn red led on

    if(dip == 15) // Delete all codes
    {
        for(uint8_t i = 0; i<15; i++) eeprom_write_word(&codes[i], 0);
    }
    else
    {
        sei();
        for(;;)
        {
            cli();
            data = rc5Data;
            rc5Data = 0;
            sei();
            if(data) break;          
        }
        eeprom_write_word(&codes[dip], data);
        eeprom_busy_wait();
    }

    PORTD &= ~(1 << 7); // turn red led off
    PORTD |= 1 << 6; // turn green led on

	for(;;);
}

// Normal Mode
// Waiting vor IR-signal and process it
void normalMode(){
    uint16_t codearray[15];
    uint16_t data = 0;
    uint8_t number = 0;

    eeprom_read_block(codearray, codes, sizeof(uint16_t)*15);

    sei();
    for(;;){
        number = 0;
        cli();
        data = rc5Data;
        rc5Data = 0;
        sei();
        if(data){
            for(uint8_t i=0; i<15; i++){ // Get Codenumber
                if(codearray[i] == data){
                    number = i;
                    break;
                }       
            }
            if(number == 0) continue; // Kein bekannter Code
            led(5); // Switch receiver Led on
            if(number > 8){ // Steuercodes
                sicherung = 1 << (number - 9);
                seccounter = 0;
            }
            else{ // Ausgang schalten
                switch(number){
                    case 1:
                        PORTC |= 1 << 5;
                        _delay_ms(10);
                        break;
                    case 2:
                        PORTC |= 1 << 4;
                        _delay_ms(10);
                        break;
                    case 3:
                        PORTC |= 1 << 3;
                        _delay_ms(10);
                        break;
                    case 4:
                        PORTC |= 1 << 2;
                        _delay_ms(10);
                        break;
                    default:
                        led(7); // Switch red led on
                }
            }
        }
    }
}

// 

// Finding RC5 Code
void rc5(){
    uint16_t tmp = rc5Tmp;	// for faster access

    TCNT0 = -2;				// 2 * 256 = 512 cycle

    if( ++rc5Time > PULSE_MAX ){			                    // count pulse time
        if( !(tmp & 0x4000) && tmp & 0x2000 ) rc5Data = tmp;	// only if 14 bits received        
        tmp = 0;
    }

    if( (rc5Bit ^ IR_IN) & 1 << IR_PIN ){		// change detect
        rc5Bit = ~rc5Bit;				        // 0x00 -> 0xFF -> 0x00
        if( rc5Time < PULSE_MIN ) tmp = 0;		// to short      
        if( !tmp || rc5Time > PULSE_1_2 ){		// start or long pulse time
            if( !(tmp & 0x4000) ) tmp <<= 1;	// not to many bits
            if( !(rc5Bit & 1 << IR_PIN) ) tmp |= 1;
            rc5Time = 0;				        // count next pulse time
        }
    }

    rc5Tmp = tmp;
}