#include <stdio.h>
#include "driver/gpio.h"
#include "esp_adc/adc_oneshot.h"
#include "esp_rom_delay.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"

#define SHCP_PIN GPIO_NUM_5
#define STCP_PIN GPIO_NUM_4
#define DS_PIN GPIO_NUM_2
#define LED1_PIN GPIO_NUM_18
#define LED2_PIN GPIO_NUM_19
#define POT1_CH ADC_CHANNEL_6  // GPIO34
#define POT2_CH ADC_CHANNEL_7  // GPIO35
#define POT3_CH ADC_CHANNEL_4  // GPIO32

static const uint8_t segmentCodes[] = {
    0b11000000, // 0
    0b11111001, // 1
    0b10100100, // 2
    0b10110000, // 3
    0b10011001, // 4
    0b10010010, // 5
    0b10000010, // 6
    0b11111000, // 7
    0b10000000, // 8
    0b10010000, // 9
};

static void shiftOut(gpio_num_t dataPin, gpio_num_t clockPin, bool msbFirst, uint8_t val) {
    for (int i = 0; i < 8; i++) {
        int bit = msbFirst ? (val >> (7 - i)) & 0x01 : (val >> i) & 0x01;
        gpio_set_level(dataPin, bit);
        gpio_set_level(clockPin, 0);
        esp_rom_delay_us(1);
        gpio_set_level(clockPin, 1);
        esp_rom_delay_us(1);
    }
}

static void displayNumber(int number) {
    number = number < 0 ? 0 : (number > 99 ? 99 : number);
    uint8_t tensCode = segmentCodes[number / 10];
    uint8_t onesCode = segmentCodes[number % 10];
    
    shiftOut(DS_PIN, SHCP_PIN, true, onesCode);
    shiftOut(DS_PIN, SHCP_PIN, true, tensCode);
    
    gpio_set_level(STCP_PIN, 1);
    esp_rom_delay_us(1);
    gpio_set_level(STCP_PIN, 0);
}

void app_main() {
    // GPIO Configuration
    gpio_config_t io_conf = {
        .pin_bit_mask = (1ULL << SHCP_PIN) | (1ULL << STCP_PIN) | (1ULL << DS_PIN) |
                        (1ULL << LED1_PIN) | (1ULL << LED2_PIN),
        .mode = GPIO_MODE_OUTPUT,
        .pull_up_en = GPIO_PULLUP_DISABLE,
        .pull_down_en = GPIO_PULLDOWN_DISABLE,
        .intr_type = GPIO_INTR_DISABLE,
    };
    gpio_config(&io_conf);

    // ADC Configuration
    adc_oneshot_unit_handle_t adc_handle;
    adc_oneshot_unit_init_cfg_t adc_config = {
        .unit_id = ADC_UNIT_1,
        .ulp_mode = ADC_ULP_MODE_DISABLE,
    };
    ESP_ERROR_CHECK(adc_oneshot_new_unit(&adc_config, &adc_handle));

    adc_oneshot_chan_cfg_t channel_config = {
        .atten = ADC_ATTEN_DB_12,
        .bitwidth = ADC_BITWIDTH_12,
    };

    ESP_ERROR_CHECK(adc_oneshot_config_channel(adc_handle, POT1_CH, &channel_config));
    ESP_ERROR_CHECK(adc_oneshot_config_channel(adc_handle, POT2_CH, &channel_config));
    ESP_ERROR_CHECK(adc_oneshot_config_channel(adc_handle, POT3_CH, &channel_config));

    displayNumber(0);

    while (1) {
        int pot1Value, pot2Value, pot3Value;
        adc_oneshot_read(adc_handle, POT1_CH, &pot1Value);
        adc_oneshot_read(adc_handle, POT2_CH, &pot2Value);
        adc_oneshot_read(adc_handle, POT3_CH, &pot3Value);

        int displayedNumber = (pot3Value * 99) / 4095;
        displayNumber(displayedNumber);

        if (displayedNumber % 2 == 0) {
            gpio_set_level(LED1_PIN, (pot1Value > 2047) ? 1 : 0);
            gpio_set_level(LED2_PIN, 0);
        } else {
            gpio_set_level(LED1_PIN, 0);
            gpio_set_level(LED2_PIN, (pot2Value > 2047) ? 1 : 0);
        }

        vTaskDelay(pdMS_TO_TICKS(100));
    }
}