/*Toggling an led on each button press*/

#include <stdio.h>
#include <stdbool.h>
#include <pico/stdlib.h>
#include <hardware/gpio.h>
#include <pico/time.h>

#define BUTTON_PIN 14       // Define the input pin (button)
#define LED_PIN 25          // led pin

volatile bool led_state = false;

absolute_time_t last_interrupt_time;

// Interrupt handler function
void gpio_callback(uint gpio, uint32_t events) {
    absolute_time_t now = get_absolute_time();
    if (absolute_time_diff_us(last_interrupt_time, now) > 20000) { // 20ms debounce
        if (gpio == BUTTON_PIN && (events & GPIO_IRQ_EDGE_FALL)) {
            led_state = !led_state;
            gpio_put(LED_PIN, led_state);
            printf("pressed");
        }
        last_interrupt_time = now;
    }
}

int main(){
    stdio_init_all();       // Initialize stdio for printf output (via USB)

    //Initilize GPIO button pin
    gpio_init(BUTTON_PIN);
    gpio_set_dir(BUTTON_PIN, GPIO_IN);
    gpio_pull_up(BUTTON_PIN);               //pushbutton is connected to GND 

    //Initialize GPIO Led pin
    gpio_init(LED_PIN);
    gpio_set_dir(LED_PIN, GPIO_OUT);
    gpio_put(LED_PIN, led_state);

    // Enable interrupt on falling edge
    gpio_set_irq_enabled_with_callback(BUTTON_PIN, GPIO_IRQ_EDGE_FALL, true, &gpio_callback );

    // Main loop can do other tasks
    while (1) {
        tight_loop_contents(); // low power idle
    }

}