#ifndef __DHT20_H__
#define __DHT20_H__

#include "../common/i2c_device.h"
#include <esp_err.h>

// DHT20 I2C address (fixed)
#define DHT20_I2C_ADDR 0x38

// DHT20 register addresses
#define DHT20_RESET_REG 0xBA
#define DHT20_CALIBRATE_REG 0xE1

// Status register bits
#define DHT20_STATUS_BUSY_BIT 0x80      // bit[7]: 1 = measuring, 0 = idle
#define DHT20_STATUS_CALIBRATED_BIT 0x08 // bit[3]: 1 = calibrated, 0 = not calibrated

/**
 * @brief DHT20 temperature and humidity sensor driver
 *
 * This driver implements the complete DHT20 I2C protocol including:
 * - Sensor initialization and calibration check
 * - Temperature and humidity measurement
 * - Automatic sensor reset and configuration
 */
class DHT20 : public I2cDevice {
public:
    /**
     * @brief Construct a new DHT20 sensor
     *
     * @param i2c_bus I2C bus handle
     */
    DHT20(i2c_master_bus_handle_t i2c_bus);

    /**
     * @brief Initialize and calibrate the sensor
     *
     * This function performs:
     * 1. Sensor reset
     * 2. System configuration (register 0xE1)
     * 3. Calibration status verification
     *
     * @return esp_err_t ESP_OK on success
     */
    esp_err_t Initialize();

    /**
     * @brief Read temperature and humidity from sensor
     *
     * This function:
     * 1. Triggers a new measurement
     * 2. Waits for measurement completion (~80ms)
     * 3. Reads and parses the sensor data
     *
     * @param temperature Output: temperature in Celsius
     * @param humidity Output: relative humidity in percentage
     * @return esp_err_t ESP_OK on success
     */
    esp_err_t ReadTempAndHumidity(float& temperature, float& humidity);

    /**
     * @brief Check if sensor is calibrated
     *
     * @return true if calibrated (bit[3] of status = 1)
     */
    bool IsCalibrated();

private:
    /**
     * @brief Reset the sensor
     *
     * Sends reset command (0xBA) to the sensor
     *
     * @return esp_err_t ESP_OK on success
     */
    esp_err_t Reset();

    /**
     * @brief Configure system registers
     *
     * Writes [0xE1, 0x08, 0x00] to configure the sensor
     *
     * @return esp_err_t ESP_OK on success
     */
    esp_err_t SetSystemConfig();

    /**
     * @brief Read status register
     *
     * @return uint8_t Status byte (bit[7]=busy, bit[3]=calibrated)
     */
    uint8_t ReadStatus();

    /**
     * @brief Trigger a new measurement
     *
     * Sends measurement trigger command [0xAC, 0x33, 0x00]
     *
     * @return esp_err_t ESP_OK on success
     */
    esp_err_t TriggerMeasurement();

    /**
     * @brief Read raw data from sensor
     *
     * Reads 7 bytes: [status, humi_H, humi_M, humi_L|temp_H, temp_M, temp_L, CRC]
     *
     * @param buffer Output buffer (must be at least 7 bytes)
     * @param len Number of bytes to read
     * @return esp_err_t ESP_OK on success
     */
    esp_err_t ReadData(uint8_t* buffer, size_t len);

    /**
     * @brief Write multiple bytes to sensor
     *
     * @param data Data buffer to write
     * @param len Number of bytes to write
     * @return esp_err_t ESP_OK on success
     */
    esp_err_t WriteBytes(const uint8_t* data, size_t len);

    /**
     * @brief Write a single byte to sensor
     *
     * @param byte Byte to write
     * @return esp_err_t ESP_OK on success
     */
    esp_err_t WriteByte(uint8_t byte);
};

#endif // __DHT20_H__