/*
 * File:   main.c
 * Author: sfokin
 *
 * Created on March 17, 2024, 6:05 AM
 */
#pragma config FOSC = INTRCIO  // Oscillator Selection bits (INTOSC oscillator: CLKOUT function on GP4/OSC2/CLKOUT pin, I/O function on GP5/OSC1/CLKIN)
#pragma config WDTE = OFF       // Watchdog Timer Enable bit (WDT disabled)
#pragma config PWRTE = OFF      // Power-Up Timer Enable bit (PWRT disabled)
#pragma config MCLRE = OFF      // GP3/MCLR pin function select (GP3/MCLR pin function is digital I/O, MCLR internally tied to VDD)
#pragma config BOREN = OFF      // Brown-out Detect Enable bit (BOD disabled)
#pragma config CP = OFF         // Code Protection bit (Program Memory code protection is disabled)
#pragma config CPD = OFF        // Data Code Protection bit (Data memory code protection is disabled)
#define _XTAL_FREQ 4000000
#define INPUT_PINS 0b00111011   // Pins: 0,1,3,4,5

#include <xc.h>
#include "common.h"
#include "main.h"
char STATE;
char btnState;
char ir_command[4];  

void __interrupt() handle_interrupt(void)
{
    clear_bit(INTCON, 7);
    
    if(test_bit(INTCON, 0))
    {
        handle_IOC();
    }
    
    if(test_bit(PIR1, 0))
    {   
        handle_TMR1(); 
    }
    
    set_bit(INTCON, 7);
    return;
}

void main(void)
{
    init();
    
    while(1)
    {
        sleep();
    }
    
    return;
}

static inline void init()
{
    //Configure GPIO
    CMCON = 7;                  //Turn off comparator
    GPIO = 0x0;                 //Clear GPIO port
    TRISIO = 0;                 //Clear TRISIO register
    ANSEL = 0;                  //Set all pins to digital IO
    TRISIO = INPUT_PINS;        //Set 0,1,3,4,5 pins as input
    INTCONbits.GIE = 1;         //Allow Global interrupts;
    INTCONbits.GPIE = 1;        //Allow interrupt on pin change
    clear_bit(OPTION_REG, 7);   //Global weak pull-up enable
    WPU = INPUT_PINS;           //Weak pull-up for 0,1,3,4,5 pins
    IOC = INPUT_PINS;           //IOC enable for 0,1,3,4,5 pins

    ir_command[0] = 0x20;
    ir_command[1] = 0xDF;
}

static inline void handle_TMR1()
{
    flip_bit(GPIO, 2);
    TMR1 = 0;
    clear_bit(PIR1, 0);
}

static inline void handle_IOC()
{
    btnState = 0;
    handle_buttons(0);
    handle_buttons(1);
    handle_buttons(3);
    handle_buttons(4);
    handle_buttons(5);
    
    //Volume up
    if(test_bit(btnState, 5))    
    {
        ir_command[2] = 0x40;
        ir_command[3] = 0xBF;
        
        while(!GP5)
            send_command(ir_command);
    }
    
    //volume down
    if(test_bit(btnState, 4))    
    {
        ir_command[2] = 0xC0;
        ir_command[3] = 0x3F;
        
        while(!GP4)
            send_command(ir_command);
    }
    
    //input select
    if(test_bit(btnState, 3))    
    {
        ir_command[2] = 0xD0;
        ir_command[3] = 0x2F;
        
        while(!GP3)
            send_command(ir_command);
    }
    //Ok
    if(test_bit(btnState, 1))    
    {
        ir_command[2] = 0x22;
        ir_command[3] = 0xDD;
        
        while(!GP1)
            send_command(ir_command);
    }
    //Power
    if(test_bit(btnState, 0))    
    {
        ir_command[2] = 0x10;
        ir_command[3] = 0xEF;
        
        while(!GP0)
            send_command(ir_command);
    }

    clear_bit(INTCON, 0);
}

static inline void sleep()
{
    //prepare and go to sleep
    GP2 = 0; //Turn off led
    SLEEP();
}

static inline void handle_buttons(char bit)
{    
    clear_bit(btnState, bit);    
    if(!test_bit(GPIO, bit))
    {
        __delay_ms(10);            
    }
    if(!test_bit(GPIO, bit))
    {
        set_bit(btnState, bit);
    }
}
static inline void send_command(char *command)
{
    send(183);
    __delay_us(4400);
    GP2 = 0;
    send_byte(command[0]);
    send_byte(command[1]);
    send_byte(command[2]);
    send_byte(command[3]);
    send(9);
    __delay_ms(200);
}

static inline void send_byte(char byte)
{
    char mask = 0b10000000;
    for(char k=0; k<8; k++)
    {
        send(13);
        if((byte & (mask >> k)) == 0)
        {
            __delay_us(400);
        }
        else
        {
           __delay_us(1500);
        }
    }
}

static inline void send(int x)
{
    for(int i = 0; i < x; i++)
    {         
        GP2=1;
        __delay_us(26);
        GP2=0;
    }
}