/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
#pragma once

#include <AP_HAL/AP_HAL.h>
#include <AP_Common/AP_Common.h>
#include <AP_Math/AP_Math.h>

#include "Compass.h"
#include "AP_Compass_Backend.h"

class AuxiliaryBus;
class AuxiliaryBusSlave;
class AP_InertialSensor;
class AP_HMC5843_SerialBus;

class AP_Compass_HMC5843 : public AP_Compass_Backend
{
public:
    static AP_Compass_Backend *detect_i2c(Compass &compass,
                                          AP_HAL::I2CDriver *i2c);
    static AP_Compass_Backend *detect_mpu6000(Compass &compass);

    AP_Compass_HMC5843(Compass &compass, AP_HMC5843_SerialBus *bus);
    ~AP_Compass_HMC5843();

    bool init();
    void read();
    void accumulate();

private:
    static AP_Compass_Backend *_detect(Compass &compass,
                                       AP_HMC5843_SerialBus *bus);

    bool read_raw();
    bool re_initialise();
    bool read_register(uint8_t address, uint8_t *value);
    bool write_register(uint8_t address, uint8_t value);

    bool _calibrate(uint8_t calibration_gain, uint16_t expected_x,
                    uint16_t expected_yz);
    bool _detect_version();

    AP_HMC5843_SerialBus *_bus;
    AP_HAL::Semaphore *_bus_sem;

    float _scaling[3];
    float _gain_multiple;
    uint32_t _last_accum_time;

    // when unhealthy the millis() value to retry at
    uint32_t _retry_time;

    int16_t _mag_x;
    int16_t _mag_y;
    int16_t _mag_z;
    int16_t _mag_x_accum;
    int16_t _mag_y_accum;
    int16_t _mag_z_accum;
    uint8_t _accum_count;

    uint8_t _base_config;
    uint8_t _compass_instance;
    uint8_t _product_id;

    bool _initialised;
};

class AP_HMC5843_SerialBus
{
public:
    struct PACKED raw_value {
        uint8_t val[6];
    };

    virtual ~AP_HMC5843_SerialBus() { };
    virtual void set_high_speed(bool val) = 0;
    virtual uint8_t register_read(uint8_t reg, uint8_t *buf, uint8_t size) = 0;
    uint8_t register_read(uint8_t reg, uint8_t *val)
    {
        return register_read(reg, val, 1);
    }

    virtual uint8_t register_write(uint8_t reg, uint8_t val) = 0;
    virtual AP_HAL::Semaphore* get_semaphore() = 0;
    virtual uint8_t read_raw(struct raw_value *rv) = 0;
    virtual bool configure() { return true; }
    virtual bool start_measurements() { return true; }
};

class AP_HMC5843_SerialBus_I2C : public AP_HMC5843_SerialBus
{
public:
    AP_HMC5843_SerialBus_I2C(AP_HAL::I2CDriver *i2c, uint8_t addr);
    void set_high_speed(bool val) override;
    uint8_t register_read(uint8_t reg, uint8_t *buf, uint8_t size) override;
    uint8_t register_write(uint8_t reg, uint8_t val) override;
    AP_HAL::Semaphore* get_semaphore() override;
    uint8_t read_raw(struct raw_value *rv) override;

private:
    AP_HAL::I2CDriver *_i2c;
    uint8_t _addr;
};

class AP_HMC5843_SerialBus_MPU6000 : public AP_HMC5843_SerialBus
{
public:
    AP_HMC5843_SerialBus_MPU6000(AP_InertialSensor &ins, uint8_t addr);
    ~AP_HMC5843_SerialBus_MPU6000();
    void set_high_speed(bool val) override;
    uint8_t register_read(uint8_t reg, uint8_t *buf, uint8_t size) override;
    uint8_t register_write(uint8_t reg, uint8_t val) override;
    AP_HAL::Semaphore* get_semaphore() override;
    uint8_t read_raw(struct raw_value *rv) override;
    bool configure() override;
    bool start_measurements() override;

private:
    AuxiliaryBus *_bus;
    AuxiliaryBusSlave *_slave;
    bool _started;
};