/*
 * @file lsense.h
 * @brief Light sensor management.
 *
 * Created: 21.09.2025
 * Author: ThePetrovich
 *
 * Copyright YKSA - Sakha Aerospace Systems, LLC.
 * See the LICENSE file for details.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#ifndef LSENSE_H
#define LSENSE_H

#include <stdint.h>

#define NUM_BUSES       3
#define SENSORS_PER_BUS 2

enum { BUS_X = 0, BUS_Y = 1, BUS_Z = 2 };
enum { SENSOR_NEG = 0, SENSOR_POS = 1 };

/**
 * @brief Detection result for the six light sensors across three I2C buses.
 *        Reused as the response payload of #CMD_LIGHT_SENSOR_PRESENCE.
 */
typedef union lsense_presence_t {
	struct __attribute__((packed)) {
		uint8_t total_detected;
		uint8_t bus_x_count;
		uint8_t bus_x_neg_addr;
		uint8_t bus_x_pos_addr;
		uint8_t bus_y_count;
		uint8_t bus_y_neg_addr;
		uint8_t bus_y_pos_addr;
		uint8_t bus_z_count;
		uint8_t bus_z_neg_addr;
		uint8_t bus_z_pos_addr;
	};
	uint8_t bytes[10];
} __attribute__((packed)) lsense_presence_t;

/**
 * @brief Per-sensor channel values for a single read across all 6 sensors.
 *        Reused as the response payload of #CMD_READ_LIGHT_SENSORS.
 */
typedef union lsense_channel_values_t {
	struct __attribute__((packed)) {
		uint16_t bus_x_neg_value;
		uint16_t bus_x_pos_value;
		uint16_t bus_y_neg_value;
		uint16_t bus_y_pos_value;
		uint16_t bus_z_neg_value;
		uint16_t bus_z_pos_value;
	};
	uint16_t values[6];
} __attribute__((packed)) lsense_channel_values_t;

/**
 * @brief Detect all sensors on all three buses.
 *        Populates internal state used by #lsense_get_presence and
 *        #lsense_read_channel.
 */
void lsense_detect_all(void);

/**
 * @brief Fill @p out with detection results from the most recent
 *        #lsense_detect_all call.
 */
void lsense_get_presence(lsense_presence_t *out);

/**
 * @brief Read a spectral channel from all six sensors into @p out.
 * @param channel 0=red 1=green 2=blue 3=IR 4=green2
 *                5=visible (R+G+B+G2)  6=all (R+G+B+G2+IR)
 * @param out     Output values, ordered X_neg, X_pos, Y_neg, Y_pos, Z_neg, Z_pos.
 */
void lsense_read_channel(uint8_t channel, lsense_channel_values_t *out);

#endif /* LSENSE_H */