/**
 * Pi Pico PIO driving a 4-digit seven segment display example.
 *
 * Copyright (C) 2021, Uri Shaked
 */

#include <stdio.h>
#include "pico/stdlib.h"
#include "hardware/gpio.h"
#include "hardware/irq.h"
#include "hardware/timer.h"

#define IR_PIN 15 // Change this to the GPIO pin you're using for the IR receiver

volatile uint32_t ir_code = 0;
volatile bool ir_code_ready = false;
volatile uint32_t last_edge_time = 0;
volatile int bit_count = 0;
volatile bool header_received = false;

void gpio_callback(uint gpio, uint32_t events) {
    uint32_t current_time = time_us_32();
    uint32_t duration = current_time - last_edge_time;
    last_edge_time = current_time;

    Serial1.printf("Duration: %i\n", duration);

    if (events & GPIO_IRQ_EDGE_FALL) {
        if (!header_received) {
            if (duration > 4400 && duration < 5500) {
                // Start bit detected
                header_received = true;
                ir_code = 0;
                bit_count = 0;
                
            }
            
        } else if (bit_count < 32) {
            ir_code <<= 1;
            if (duration > 1600) {
                ir_code |= 1;
            }
            bit_count++;
            if (bit_count == 32) {
                ir_code_ready = true;
                header_received = false;
            }
        }
    }
}

void setup() {
  Serial1.begin(115200);

  Serial1.println("Raspberry Pi Pico PIO 7-Segment Example\n");

  gpio_init(IR_PIN);
  gpio_set_dir(IR_PIN, GPIO_IN);
  gpio_pull_up(IR_PIN);

  gpio_set_irq_enabled_with_callback(IR_PIN, GPIO_IRQ_EDGE_FALL | GPIO_IRQ_EDGE_RISE, true, &gpio_callback);
}

int i = 0;
void loop() {
  sleep_ms(50);  // Simulating other tasks
  if (ir_code_ready) {
    Serial1.printf("Received IR code: 0x%08lX\n", (ir_code & 0x0000FF00) );
    if ((ir_code & 0x0000FF00) != (~(ir_code << 8) & 0x0000FF00)) {
      Serial1.printf("Error Detected! 0x%08lX 0x%08lX\n", (ir_code & 0x0000FF00), (~(ir_code << 8) & 0x0000FF00));
    }
    ir_code_ready = false;
  }
}