#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "driver/gpio.h"
#include "freertos/FreeRTOS.h"
#include "freertos/queue.h"
#include "freertos/task.h"

#define GPIO_OUTPUT_IO_0 5
#define GPIO_OUTPUT_IO_1 6
#define GPIO_OUTPUT_PIN_SEL \
  ((1ULL << GPIO_OUTPUT_IO_0) | (1ULL << GPIO_OUTPUT_IO_1))
#define ENCODER_0_CLK_PIN CONFIG_ENCODER_0_CLK_PIN
#define ENCODER_0_DT_PIN CONFIG_ENCODER_0_DT_PIN
#define ENCODER_0_CLK_PIN_MASK 1ULL << ENCODER_0_CLK_PIN
#define ENCODER_0_DT_PIN_MASK 1ULL << ENCODER_0_DT_PIN
#define ENCODER_1_CLK_PIN CONFIG_ENCODER_1_CLK_PIN
#define ENCODER_1_DT_PIN CONFIG_ENCODER_1_DT_PIN
#define ENCODER_1_CLK_PIN_MASK 1ULL << ENCODER_1_CLK_PIN
#define ENCODER_1_DT_PIN_MASK 1ULL << ENCODER_1_DT_PIN
#define ESP_INTR_FLAG_DEFAULT 0

#define NOT_ROTATING -1
#define CLOCKWISE 1
#define COUNTER_CLOCKWISE 0

#define UI_INPUT_DISPLAY_0_BRIGHTNESS 1
#define UI_INPUT_DISPLAY_1_BRIGHTNESS 2

typedef struct s_ui_input {
  uint8_t key;
  uint16_t value;
} s_ui_input_t;

static xQueueHandle ui_input_event = NULL;

static int8_t rising_edge_rotation_direction = NOT_ROTATING;
static int8_t falling_edge_rotation_direction = NOT_ROTATING;
static uint8_t display_0_brightness = 20;
static uint8_t display_1_brightness = 20;

static s_ui_input_t current_ui_input = {};

uint8_t input_key;
uint8_t clk_pin = ENCODER_0_CLK_PIN;
uint8_t dt_level;
uint8_t dt_pin = ENCODER_0_DT_PIN;
uint8_t* value = &display_0_brightness;

static void IRAM_ATTR gpio_isr_handler(void* arg) {
  uint8_t input_key = (uint8_t)arg;

  switch (input_key) {
    case UI_INPUT_DISPLAY_0_BRIGHTNESS:
      clk_pin = ENCODER_0_CLK_PIN;
      dt_pin = ENCODER_0_DT_PIN;
      value = &display_0_brightness;
      break;
    case UI_INPUT_DISPLAY_1_BRIGHTNESS:
      clk_pin = ENCODER_1_CLK_PIN;
      dt_pin = ENCODER_1_DT_PIN;
      value = &display_1_brightness;
      break;
    default:
      break;
  }
  dt_level = gpio_get_level(dt_pin);
  if (gpio_get_level(clk_pin)) {
    rising_edge_rotation_direction = dt_level == 0;
    if (falling_edge_rotation_direction == rising_edge_rotation_direction) {
      if (rising_edge_rotation_direction) {
        gpio_set_level(GPIO_OUTPUT_IO_0, 1);
        gpio_set_level(GPIO_OUTPUT_IO_1, 0);
        *value += 1;
      } else {
        gpio_set_level(GPIO_OUTPUT_IO_0, 0);
        gpio_set_level(GPIO_OUTPUT_IO_1, 1);
        *value -= 1;
      }
      falling_edge_rotation_direction = NOT_ROTATING;

      current_ui_input.key = input_key;
      current_ui_input.value = *value;
      xQueueSendFromISR(ui_input_event, &current_ui_input, NULL);
    } else {
      if (falling_edge_rotation_direction != NOT_ROTATING) {
        rising_edge_rotation_direction = NOT_ROTATING;
      }
    }
  } else {
    falling_edge_rotation_direction = dt_level;
    // printf("F %d\t", falling_edge_rotation_direction);
    if (rising_edge_rotation_direction == falling_edge_rotation_direction) {
      if (falling_edge_rotation_direction) {
        gpio_set_level(GPIO_OUTPUT_IO_0, 1);
        gpio_set_level(GPIO_OUTPUT_IO_1, 0);
        *value += 1;
      } else {
        gpio_set_level(GPIO_OUTPUT_IO_0, 0);
        gpio_set_level(GPIO_OUTPUT_IO_1, 1);
        *value -= 1;
      }
      rising_edge_rotation_direction = NOT_ROTATING;

      current_ui_input.key = input_key;
      current_ui_input.value = *value;
      xQueueSendFromISR(ui_input_event, &current_ui_input, NULL);

    } else {
      if (rising_edge_rotation_direction != NOT_ROTATING) {
        falling_edge_rotation_direction = NOT_ROTATING;
      }
    }
  }
}

void init_ui(void) {
  // zero-initialize the config structure.
  gpio_config_t io_conf = {};
  // disable interrupt
  io_conf.intr_type = GPIO_INTR_DISABLE;
  // set as output mode
  io_conf.mode = GPIO_MODE_OUTPUT;
  // bit mask of the pins that you want to set,e.g.GPIO18/19
  io_conf.pin_bit_mask = GPIO_OUTPUT_PIN_SEL;
  // disable pull-down mode
  io_conf.pull_down_en = 0;
  // disable pull-up mode
  io_conf.pull_up_en = 0;
  // configure GPIO with the given settings
  gpio_config(&io_conf);

  io_conf.mode = GPIO_MODE_INPUT;
  io_conf.pull_up_en = 1;
  io_conf.pull_down_en = 0;
  // interrupt of rising edge
  io_conf.intr_type = GPIO_INTR_ANYEDGE;
  io_conf.pin_bit_mask = ENCODER_0_CLK_PIN_MASK | ENCODER_1_CLK_PIN_MASK;
  gpio_config(&io_conf);
  io_conf.intr_type = GPIO_INTR_DISABLE;
  io_conf.pin_bit_mask = ENCODER_0_DT_PIN_MASK | ENCODER_1_DT_PIN_MASK;
  gpio_config(&io_conf);

  // start encoder task
  ui_input_event = xQueueCreate(10, sizeof(s_ui_input_t));

  // install gpio isr service
  gpio_install_isr_service(ESP_INTR_FLAG_DEFAULT);
  // hook isr handler for specific gpio pin
  gpio_isr_handler_add(ENCODER_0_CLK_PIN, gpio_isr_handler,
                       (void*)UI_INPUT_DISPLAY_0_BRIGHTNESS);
  // hook isr handler for specific gpio pin
  gpio_isr_handler_add(ENCODER_1_CLK_PIN, gpio_isr_handler,
                       (void*)UI_INPUT_DISPLAY_1_BRIGHTNESS);
}