#include <stdio.h>
#include "pico/stdlib.h"
#include "hardware/adc.h"
#include "hardware/dma.h"
#include "hardware/i2c.h"
#include "ssd1306.h" // Adicione o caminho correto da biblioteca

#define I2C_PORT i2c0
#define I2C_SDA_PIN 4
#define I2C_SCL_PIN 5
#define BUFFER_SIZE 1

uint16_t adc_buffer[BUFFER_SIZE];

float convert_to_celsius(uint16_t raw) {
    const float conversion_factor = 3.3f / (1 << 12);
    float voltage = raw * conversion_factor;
    float temperature = 27 - (voltage - 0.706f) / 0.001721f;
    return temperature;
}

int main() {
    stdio_init_all();
    sleep_ms(500); // Aguarda inicialização

    // Inicializa I2C e Display
    i2c_init(I2C_PORT, 400 * 1000);
    gpio_set_function(I2C_SDA_PIN, GPIO_FUNC_I2C);
    gpio_set_function(I2C_SCL_PIN, GPIO_FUNC_I2C);
    gpio_pull_up(I2C_SDA_PIN);
    gpio_pull_up(I2C_SCL_PIN);

    ssd1306_init(I2C_PORT, 0x3C, I2C_SDA_PIN, I2C_SCL_PIN);
    ssd1306_clear();
    ssd1306_show();

    // Inicializa ADC
    adc_init();
    adc_set_temp_sensor_enabled(true);
    adc_select_input(4);
    adc_fifo_setup(true, true, 1, false, false);

    // Configura DMA
    int dma_chan = dma_claim_unused_channel(true);
    dma_channel_config dma_cfg = dma_channel_get_default_config(dma_chan);
    channel_config_set_transfer_data_size(&dma_cfg, DMA_SIZE_16);
    channel_config_set_read_increment(&dma_cfg, false);
    channel_config_set_write_increment(&dma_cfg, true);
    channel_config_set_dreq(&dma_cfg, DREQ_ADC);

    char display_buf[32];

    while (true) {
        adc_run(true);
        dma_channel_configure(
            dma_chan,
            &dma_cfg,
            adc_buffer,           // Destino (RAM)
            &adc_hw->fifo,        // Origem (FIFO do ADC)
            BUFFER_SIZE,          // Número de amostras
            true                  // Iniciar agora
        );
        dma_channel_wait_for_finish_blocking(dma_chan);
        adc_run(false);

        float temperature = convert_to_celsius(adc_buffer[0]);
        snprintf(display_buf, sizeof(display_buf), "Temp: %.2f C", temperature);

        // Exibir no OLED
        ssd1306_clear();
        ssd1306_draw_string(0, 0, display_buf);
        ssd1306_show();

        sleep_ms(500);
    }

    return 0;
}