/*
 * Copyright (c) 2018, Sensirion AG
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 *
 * * Neither the name of Sensirion AG nor the names of its
 *   contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "sensirion_i2c_hal.h"
#include "sensirion_common.h"
#include "sensirion_config.h"

#include "driver/i2c.h"

#include <stdio.h>
/*
 * INSTRUCTIONS
 * ============
 *
 * Implement all functions where they are marked as IMPLEMENT.
 * Follow the function specification in the comments.
 */

/**
 * Select the current i2c bus by index.
 * All following i2c operations will be directed at that bus.
 *
 * THE IMPLEMENTATION IS OPTIONAL ON SINGLE-BUS SETUPS (all sensors on the same
 * bus)
 *
 * @param bus_idx   Bus index to select
 * @returns         0 on success, an error code otherwise
 */
int16_t sensirion_i2c_hal_select_bus(uint8_t bus_idx) {
    /* TODO:IMPLEMENT or leave empty if all sensors are located on one single
     * bus
     */
    return NOT_IMPLEMENTED_ERROR;
}

/**
 * Initialize all hard- and software components that are needed for the I2C
 * communication.
 */
void sensirion_i2c_hal_init(int SDA, int SCL) {
	int i2c_master_port = I2C_NUM_0;
	i2c_config_t conf = {
		.mode = I2C_MODE_MASTER,
		.sda_io_num = SDA,         // select GPIO specific to your project
		.sda_pullup_en = GPIO_PULLUP_ENABLE,
		.scl_io_num = SCL,         // select GPIO specific to your project
		.scl_pullup_en = GPIO_PULLUP_ENABLE,
		.master.clk_speed = 10000,  // select frequency specific to your project
		// .clk_flags = 0,          /*!< Optional, you can use I2C_SCLK_SRC_FLAG_* flags to choose i2c source clock here. */
	};
	i2c_param_config(i2c_master_port, &conf);

	i2c_driver_install(i2c_master_port, I2C_MODE_MASTER, 0, 0, 0);
}

/**
 * Release all resources initialized by sensirion_i2c_hal_init().
 */
void sensirion_i2c_hal_free(void) {
	i2c_driver_delete(I2C_NUM_0); /* TODO:non const port */
}

/**
 * Execute one read transaction on the I2C bus, reading a given number of bytes.
 * If the device does not acknowledge the read command, an error shall be
 * returned.
 *
 * @param address 7-bit I2C address to read from
 * @param data    pointer to the buffer where the data is to be stored
 * @param count   number of bytes to read from I2C and store in the buffer
 * @returns 0 on success, error code otherwise
 */
int8_t sensirion_i2c_hal_read(uint8_t address, uint8_t* data, uint16_t count) {
	i2c_cmd_handle_t cmdLnk = i2c_cmd_link_create();
	esp_err_t err = ESP_OK;
	err = i2c_master_start(cmdLnk);
	err = i2c_master_write_byte(cmdLnk, address << 1 | I2C_MASTER_READ, true);
	err = i2c_master_read(cmdLnk, data, count-1, I2C_MASTER_ACK);
	err = i2c_master_read(cmdLnk, data + count - 1, 1, I2C_MASTER_NACK);
	err = i2c_master_stop(cmdLnk);
	i2c_master_cmd_begin(I2C_NUM_0,cmdLnk,1000 / portTICK_RATE_MS);
	i2c_cmd_link_delete(cmdLnk);
	return err;
}

/**
 * Execute one write transaction on the I2C bus, sending a given number of
 * bytes. The bytes in the supplied buffer must be sent to the given address. If
 * the slave device does not acknowledge any of the bytes, an error shall be
 * returned.
 *
 * @param address 7-bit I2C address to write to
 * @param data    pointer to the buffer containing the data to write
 * @param count   number of bytes to read from the buffer and send over I2C
 * @returns 0 on success, error code otherwise
 */
int8_t sensirion_i2c_hal_write(uint8_t address, const uint8_t* data,
                               uint16_t count) {
	i2c_cmd_handle_t cmdLnk = i2c_cmd_link_create();
	esp_err_t err = ESP_OK;
	err = i2c_master_start(cmdLnk);
	err = i2c_master_write_byte(cmdLnk, address << 1 | I2C_MASTER_WRITE, true);
	err = i2c_master_write(cmdLnk, data, count, true);
	err = i2c_master_stop(cmdLnk);
	i2c_master_cmd_begin(I2C_NUM_0,cmdLnk,1000 / portTICK_RATE_MS); /* TODO:non const port */
	i2c_cmd_link_delete(cmdLnk);
	return err;
}

/**
 * Sleep for a given number of microseconds. The function should delay the
 * execution for at least the given time, but may also sleep longer.
 *
 * Despite the unit, a <10 millisecond precision is sufficient.
 *
 * @param useconds the sleep time in microseconds
 */
void sensirion_i2c_hal_sleep_usec(uint32_t useconds) {
	vTaskDelay(useconds / portTICK_PERIOD_MS / 1000);
}