//! Button Interrupt
//!
//! Solution
// Reference: https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/system/freertos.html
use anyhow::Result;
use std::thread;
use esp_idf_hal::{prelude::Peripherals};
use esp_idf_sys::{
    gpio_config, gpio_config_t, gpio_install_isr_service,
    gpio_int_type_t_GPIO_INTR_POSEDGE, gpio_isr_handler_add, gpio_mode_t_GPIO_MODE_INPUT,
    gpio_int_type_t_GPIO_INTR_NEGEDGE
};

use std::time::Duration;

// This `static mut` holds the queue handle we are going to get from `xQueueGenericCreate`.
// This is unsafe, but we are careful not to enable our GPIO interrupt handler until after this value has been initialised, and then never modify it again

static mut counter:u32 = 10;
#[no_mangle]
#[inline(never)]
#[link_section = ".iram1"]
unsafe extern "C" fn button_interrupt(_: *mut core::ffi::c_void) {
    unsafe{
      counter+=1;  
    } 
}

pub fn intr_counter() {
    counter+=1;
}

fn main() -> Result<()> {
    let peripherals = Peripherals::take().unwrap();
    //let mut led = PinDriver::output(peripherals.pins.gpio2)?;

    const GPIO_NUM: i32 = 9;
    // Configures the button
    let io_conf = gpio_config_t {
        pin_bit_mask: 1 << GPIO_NUM,
        mode: gpio_mode_t_GPIO_MODE_INPUT,
        pull_up_en: true.into(),
        pull_down_en: false.into(),
        intr_type: gpio_int_type_t_GPIO_INTR_NEGEDGE, // Positive edge trigger = button down
    };

    unsafe {
        // Writes the button configuration to the registers
        /*esp!(gpio_config(&io_conf))?;

        // Installs the generic GPIO interrupt handler
        esp!(gpio_install_isr_service(0))?;

        // Registers our function with the generic GPIO interrupt handler we installed earlier.
        esp!(gpio_isr_handler_add(
            GPIO_NUM,
            Some(button_interrupt),
            std::ptr::null_mut()
        ))?;*/

        gpio_config(&io_conf);

        // Installs the generic GPIO interrupt handler
        gpio_install_isr_service(0);

        // Registers our function with the generic GPIO interrupt handler we installed earlier.
        gpio_isr_handler_add(
            GPIO_NUM,
            Some(button_interrupt),
            std::ptr::null_mut()
        );
    }

    // Reads the queue in a loop.
    loop {
        unsafe {
            thread::sleep(Duration::from_millis(100));
            println!("hello world {}", counter);
            // If the event has the value 0, nothing happens. if it has a different value, the button was pressed.
            // If the button was pressed, a function that changes the state of the LED is called.
            //led.set_high()?;
        }
    }
}