#include <stdint.h>

#include "driver/gpio.h"
#include "esp_log.h"
#include "esp_sleep.h"

#include "freertos/FreeRTOS.h"
#include "freertos/task.h"

#include "wifi_provisioning.h"

#include "next_button.h"

static const char *TAG = "next_button";

#if CONFIG_FRAME_NEXT_BUTTON_GPIO >= 0

#define NEXT_BUTTON_GPIO ((gpio_num_t)CONFIG_FRAME_NEXT_BUTTON_GPIO)
#define NEXT_BUTTON_DEBOUNCE_MS 20
#define NEXT_BUTTON_DEBOUNCE_CHECKS 3
#define NEXT_BUTTON_POLL_MS 100

void next_button_init(void)
{
    /* Every deep sleep with this pin armed as a wakeup source leaves it
     * "held" (ESP-IDF locks the pin's pull/config across the sleep
     * transition -- see esp_sleep_gpio_wakeup_prepare_on_hp_periph_powerdown()
     * in sleep_modes.c) and, confirmed on hardware, never un-holds it on
     * wake -- the application has to. Must run before gpio_config() below. */
    gpio_hold_dis(NEXT_BUTTON_GPIO);

    gpio_config_t io_conf = {
        .pin_bit_mask = 1ULL << NEXT_BUTTON_GPIO,
        .mode = GPIO_MODE_INPUT,
        .pull_up_en = GPIO_PULLUP_ENABLE,
    };
    gpio_config(&io_conf);

    /* Not esp_sleep_enable_ext1_wakeup_io(): its internal pull resistors
     * don't hold once the RTC_PERIPH domain powers down for deep sleep, so
     * the pin floats and reads spuriously low, waking the device instantly
     * on every sleep entry (confirmed on hardware). This GPIO-wakeup
     * variant manages the pull resistor itself across the sleep
     * transition. */
    esp_sleep_enable_gpio_wakeup_on_hp_periph_powerdown(1ULL << NEXT_BUTTON_GPIO, ESP_GPIO_WAKEUP_GPIO_LOW);
}

next_button_result_t next_button_check(void)
{
    /* A quick tap can easily release before this runs (~0.4-0.5s into
     * boot, confirmed on hardware -- a live gpio_get_level() check here
     * missed real presses that had already woken the device). The wakeup
     * status register is latched at the moment of waking and isn't
     * cleared until the next sleep entry, so it reliably reflects a tap
     * regardless of how quickly it was released. */
    bool caused_wake = esp_sleep_get_gpio_wakeup_status() & (1ULL << NEXT_BUTTON_GPIO);

    if (!caused_wake) {
        /* Not a GPIO-wakeup-from-this-pin boot (normal timer wake, or a
         * fresh power-on/reflash) -- fall back to a live, debounced level
         * check so holding the button down while powering on also
         * works. */
        if (gpio_get_level(NEXT_BUTTON_GPIO) != 0) {
            return NEXT_BUTTON_NOT_PRESSED;
        }
        for (int i = 0; i < NEXT_BUTTON_DEBOUNCE_CHECKS; i++) {
            vTaskDelay(pdMS_TO_TICKS(NEXT_BUTTON_DEBOUNCE_MS));
            if (gpio_get_level(NEXT_BUTTON_GPIO) != 0) {
                return NEXT_BUTTON_NOT_PRESSED; /* noise, not a real press */
            }
        }
    }

    /* Confirmed pressed (either the wake cause, or debounced during
     * power-on) -- measure how long, same polling pattern as
     * combo_button.c's own hold-tier detection. Reads the last hold
     * duration the server reported (persisted from a previous cycle,
     * see frame_config_get_hold_duration_ms's own doc comment), falling
     * back to the Kconfig default before the device has ever fetched
     * one. */
    uint32_t hold_threshold_ms;
    if (frame_config_get_hold_duration_ms(&hold_threshold_ms) != ESP_OK) {
        hold_threshold_ms = CONFIG_FRAME_HOLD_ACTION_MS;
    }

    uint32_t elapsed_ms = 0;
    while (gpio_get_level(NEXT_BUTTON_GPIO) == 0) {
        if (elapsed_ms >= hold_threshold_ms) {
            ESP_LOGI(TAG, "Next button held past %ums, triggering global hold action",
                     (unsigned)hold_threshold_ms);
            return NEXT_BUTTON_HOLD;
        }
        vTaskDelay(pdMS_TO_TICKS(NEXT_BUTTON_POLL_MS));
        elapsed_ms += NEXT_BUTTON_POLL_MS;
    }

    ESP_LOGI(TAG, "Next-photo button short press (%ums), forcing advance", (unsigned)elapsed_ms);
    return NEXT_BUTTON_SHORT_PRESS;
}

#else

void next_button_init(void) {}
next_button_result_t next_button_check(void) { return NEXT_BUTTON_NOT_PRESSED; }

#endif