/*
 * SPDX-FileCopyrightText: 2015-2025 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include "bh1750.h"
#include "driver/i2c_master.h"
#include "freertos/FreeRTOS.h"
#include "freertos/projdefs.h"	// for pdMS_TO_TICKS

#define BH_1750_MEASUREMENT_ACCURACY                                                               \
	1.2 /*!< the typical measurement accuracy of  BH1750 sensor                                    \
		 */

#define BH1750_POWER_DOWN 0x00 /*!< Command to set Power Down*/
#define BH1750_POWER_ON 0x01   /*!< Command to set Power On*/
#define I2C_CLK_SPEED 400000


typedef struct
{
	i2c_master_dev_handle_t i2c_handle;
} bh1750_dev_t;

static esp_err_t bh1750_write_byte(const bh1750_dev_t* const sens, const uint8_t byte)
{ return i2c_master_transmit(sens->i2c_handle, &byte, 1, pdMS_TO_TICKS(1000)); }

esp_err_t bh1750_create(i2c_master_bus_handle_t i2c_bus,
						const uint8_t			dev_addr,
						bh1750_handle_t*		handle_ret)
{
	esp_err_t	  ret	 = ESP_OK;
	bh1750_dev_t* sensor = (bh1750_dev_t*) calloc(1, sizeof(bh1750_dev_t));
	if (!sensor)
	{
		return ESP_ERR_NO_MEM;
	}

	// Add new I2C device
	const i2c_device_config_t i2c_dev_cfg = {
		.device_address = dev_addr,
		.scl_speed_hz	= I2C_CLK_SPEED,
	};
	ret = i2c_master_bus_add_device(i2c_bus, &i2c_dev_cfg, &sensor->i2c_handle);
	if (ret != ESP_OK)
	{
		free(sensor);
		return ret;
	}

	assert(sensor->i2c_handle);
	*handle_ret = sensor;
	return ret;
}

esp_err_t bh1750_delete(bh1750_handle_t sensor)
{
	bh1750_dev_t* sens = (bh1750_dev_t*) sensor;
	if (sens->i2c_handle)
	{
		i2c_master_bus_rm_device(sens->i2c_handle);
	}
	free(sens);
	return ESP_OK;
}

esp_err_t bh1750_power_down(bh1750_handle_t sensor)
{
	bh1750_dev_t* sens = (bh1750_dev_t*) sensor;
	return bh1750_write_byte(sens, BH1750_POWER_DOWN);
}

esp_err_t bh1750_power_on(bh1750_handle_t sensor)
{
	bh1750_dev_t* sens = (bh1750_dev_t*) sensor;
	return bh1750_write_byte(sens, BH1750_POWER_ON);
}

esp_err_t bh1750_set_measure_time(bh1750_handle_t sensor, const uint8_t measure_time)
{
	bh1750_dev_t* sens	 = (bh1750_dev_t*) sensor;
	uint32_t	  i		 = 0;
	uint8_t		  buf[2] = { 0x40, 0x60 };	// constant part of the the MTreg
	buf[0] |= measure_time >> 5;
	buf[1] |= measure_time & 0x1F;
	for (i = 0; i < 2; i++)
	{
		esp_err_t ret = bh1750_write_byte(sens, buf[i]);
		if (ESP_OK != ret)
		{
			return ret;
		}
	}
	return ESP_OK;
}

esp_err_t bh1750_set_measure_mode(bh1750_handle_t sensor, const bh1750_measure_mode_t cmd_measure)
{
	bh1750_dev_t* sens = (bh1750_dev_t*) sensor;
	return bh1750_write_byte(sens, (uint8_t) cmd_measure);
}

esp_err_t bh1750_get_data(bh1750_handle_t sensor, float* const data)
{
	bh1750_dev_t* sens = (bh1750_dev_t*) sensor;
	uint8_t		  read_buffer[2];
	esp_err_t	  ret = i2c_master_receive(
		sens->i2c_handle, read_buffer, sizeof(read_buffer), pdMS_TO_TICKS(1000));
	if (ESP_OK != ret)
	{
		return ret;
	}
	*data = ((read_buffer[0] << 8 | read_buffer[1]) / BH_1750_MEASUREMENT_ACCURACY);
	return ESP_OK;
}