#include <avr/io.h>
#include "input_handler.h"
#include "timer_counter.h"

typedef void (*ButtonRoutine_t)(ButtonKey_t *);

const ButtonRoutine_t button_routine[MAX_STATE];

void buttonHandler(ButtonKey_t *key)
{
    button_routine[key->state](key);
}

static inline GPIO_PinState getPinState(ButtonKey_t *key)
{
    // Read the pin state from the register
    return (*(key->instance.pin_register) & (1 << key->instance.pin_number)) ? GPIO_PIN_SET : GPIO_PIN_RESET;
}

static void buttonIdleRoutine(ButtonKey_t *key)
{
    if (getPinState(key) == key->active_state)
    {
        key->state = DEBOUNCE;
        key->last_tick = ticks100us();
    }
}

static void buttonActiveRoutine(ButtonKey_t *key)
{
    if (getPinState(key) != key->active_state)
    {
        key->state = DEBOUNCE;
        key->last_tick = ticks100us();
    }
}

static void buttonDebounceRoutine(ButtonKey_t *key)
{
    // Read the current pin state
    GPIO_PinState pin_now = getPinState(key);
    ButtonState_t new_state = (pin_now == key->active_state) ? ACTIVE : IDLE;

    // Check if debounce time has passed
    uint16_t debounce_time = (new_state == ACTIVE) ? key->timer_debounce_on : key->timer_debounce_off;
    if ((ticks100us() - key->last_tick) < debounce_time)
    {
        return; // Still in debounce period, do nothing
    }

    // If the new state is the same as the last state, we return to the previous state
    if (new_state == key->last_state)
    {
        key->state = key->last_state;
        return;
    }

    // Update the last state and current state
    key->last_state = new_state;
    key->state = new_state;

    if (new_state == ACTIVE && key->buttonPressed)
    {
        key->buttonPressed(key);
    }
    else if (new_state == IDLE && key->buttonReleased)
    {
        key->buttonReleased(key);
    }
}

const ButtonRoutine_t button_routine[MAX_STATE] = {
    buttonIdleRoutine,
    buttonDebounceRoutine,
    buttonActiveRoutine,
};