/**
 * @brief PUT_TEXT_HERE
 * @details This file is...
 * @author username
 * @date todays_date
 * @copyright None
 * @file module_name.h
 */

// Used during testing and for the LSP
#ifndef __AVR_ATtiny404__
#define __AVR_ATtiny404__
#endif

#include "timer.h"
#include <avr/io.h>
#include <avr/interrupt.h>

#define FCLK_PER 3333333UL
#define DIV8 0x3
#define PERIOD_VALUE 40 

//These are expiremential found values that account for overhead
//for smaller durations.
#define OVERHEAD_ONE 226
#define OVERHEAD_TWO 151
#define OVERHEAD_THREE 75


static uint16_t overflow_count = 0;


uint16_t Timer_GetOverflowCount(void)
{
    return overflow_count;
}

void Timer_Start(void)
{
    //clear the overflow event count
    overflow_count = 0;

    sei();

    //Enable the overflow Interrupt.
    TCA0.SINGLE.INTCTRL = TCA_SINGLE_OVF_bm;

    //set Normal mode.
    TCA0.SINGLE.CTRLB = TCA_SINGLE_WGMODE_NORMAL_gc;

    //Disable event counting.
    TCA0.SINGLE.EVCTRL &= ~(TCA_SINGLE_CNTEI_bm);

    //Set the Period Value
    TCA0.SINGLE.PER = PERIOD_VALUE;

    //set the Timer to divide FCLK_PER by 8.
    TCA0.SINGLE.CTRLA |= (DIV8<<1);
    
    //Enable the Timer
    TCA0.SINGLE.CTRLA |= TCA_SINGLE_ENABLE_bm;
}


void Timer_Disable(void)
{
    cli();
    TCA0.SINGLE.CTRLA &= ~(1<<0);
    TCA0.SINGLE.CTRLESET |= ((0x3)<<2);
}

//Triggered on the overflow of the timer A's counter.
ISR(TCA0_OVF_vect)
{
    cli();

    //Increment the Overflow counter.
    overflow_count += 1;

    // The interrupt flag has to be cleared manually
    TCA0.SINGLE.INTFLAGS = TCA_SINGLE_OVF_bm;

    sei();
}