#include "pico/stdlib.h"
#include "bsp/board.h"
#include "tusb.h"
#include "usb_descriptors.h"
#include "hardware/gpio.h"

#define BUTTON_PIN 10  // Pin where the button is connected

// Initialize USB and set up other peripherals
void setup() {
    board_init();                       // Initialize the board
    tusb_init();                        // Initialize TinyUSB (required for USB HID)

    gpio_init(BUTTON_PIN);              // Initialize the button pin
    gpio_set_dir(BUTTON_PIN, GPIO_IN);  // Set as input
    gpio_pull_down(BUTTON_PIN);         // Pull down to ensure low state when not pressed
}

// Function to handle button presses and send key data to the computer
void loop() {
    // Check if the USB stack is ready
    tud_task();  // Process USB events

    // If the HID is not ready, we can't send data
    if (!tud_hid_ready()) {
        return;
    }

    // If the button is pressed
    if (gpio_get(BUTTON_PIN)) {
        uint8_t keycode = 4;  // Keycode for 'a' in HID
        tud_hid_keyboard_report(0, 0, &keycode, 1);  // Send 'a'
        tud_hid_keyboard_report(0, 0, NULL, 0);  // Release key

        // Debounce: Wait for button release
        while (gpio_get(BUTTON_PIN)) {
            sleep_ms(10);
        }
    }
}

int main() {
    setup();  // Initialize hardware and USB

    while (true) {
        loop();  // Continuously check for button presses and process USB events
    }
}