#include "timer.h"

void IRAM_ATTR timer_group0_isr(void *para)
{
    int timer_idx = (int) para;

    /* Retrieve the interrupt status and the counter value
       from the timer that reported the interrupt */
    uint32_t intr_status = TIMERG0.int_st_timers.val;
    TIMERG0.hw_timer[timer_idx].update = 1;
    uint64_t timer_counter_value = 
        ((uint64_t) TIMERG0.hw_timer[timer_idx].cnt_high) << 32
        | TIMERG0.hw_timer[timer_idx].cnt_low;

    /* Prepare basic event data
       that will be then sent back to the main program task */
    timer_event_t evt;
    evt.timer_group = 0;
    evt.timer_idx = timer_idx;
    evt.timer_counter_value = timer_counter_value;

    /* Clear the interrupt
       and update the alarm time for the timer with without reload */
    if ((intr_status & BIT(timer_idx)) && timer_idx == TIMER_1) {
        evt.type = TEST_WITH_RELOAD;
        TIMERG0.int_clr_timers.t1 = 1;
    } else {
        evt.type = -1; // not supported even type
    }

    /* After the alarm has been triggered
      we need enable it again, so it is triggered the next time */
    TIMERG0.hw_timer[timer_idx].config.alarm_en = TIMER_ALARM_EN;

    /* Now just send the event data back to the main program task */
    xQueueSendFromISR(timer_queue, &evt, NULL);
}

void example_tg0_timer_init(int timer_idx, 
    bool auto_reload, double timer_interval_sec)
{
    /* Select and initialize basic parameters of the timer */
    timer_config_t config;
    config.divider = TIMER_DIVIDER;
    config.counter_dir = TIMER_COUNT_UP;
    config.counter_en = TIMER_PAUSE;
    config.alarm_en = TIMER_ALARM_EN;
    config.intr_type = TIMER_INTR_LEVEL;
    config.auto_reload = auto_reload;
    timer_init(TIMER_GROUP_0, timer_idx, &config);

    /* Timer's counter will initially start from value below.
       Also, if auto_reload is set, this value will be automatically reload on alarm */
    timer_set_counter_value(TIMER_GROUP_0, timer_idx, 0x00000000ULL);

    /* Configure the alarm value and the interrupt on alarm. */
    timer_set_alarm_value(TIMER_GROUP_0, timer_idx, timer_interval_sec * TIMER_SCALE);
    timer_enable_intr(TIMER_GROUP_0, timer_idx);
    timer_isr_register(TIMER_GROUP_0, timer_idx, timer_group0_isr, 
        (void *) timer_idx, ESP_INTR_FLAG_IRAM, NULL);

    timer_start(TIMER_GROUP_0, timer_idx);
}