/*
 * Copyright © 2014 Kosma Moczek <kosma@cloudyourcar.com>
 * This program is free software. It comes without any warranty, to the extent
 * permitted by applicable law. You can redistribute it and/or modify it under
 * the terms of the Do What The Fuck You Want To Public License, Version 2, as
 * published by Sam Hocevar. See the COPYING file for more details.
 */

#ifndef MINMEA_H
#define MINMEA_H

#ifdef __cplusplus
extern "C" {
#endif

#include <ctype.h>
#include <stdint.h>
#include <stdbool.h>
#include <time.h>
#include <math.h>
#ifdef MINMEA_INCLUDE_COMPAT
#include <minmea_compat.h>
#endif

#ifndef MINMEA_MAX_SENTENCE_LENGTH
#define MINMEA_MAX_SENTENCE_LENGTH 80
#endif

#define FRAME_TXT_MAX_LEN (79)

enum minmea_sentence_id {
    MINMEA_INVALID = -1,
    MINMEA_UNKNOWN = 0,
    MINMEA_SENTENCE_GBS,
    MINMEA_SENTENCE_GGA,
    MINMEA_SENTENCE_GLL,
    MINMEA_SENTENCE_GSA,
    MINMEA_SENTENCE_GST,
    MINMEA_SENTENCE_GSV,
    MINMEA_SENTENCE_RMC,
    MINMEA_SENTENCE_VTG,
    MINMEA_SENTENCE_ZDA,
    MINMEA_SENTENCE_TXT,

    MINMEA_SENTENCE_MAX_ID
};

struct minmea_float {
    int_least32_t value;
    int_least32_t scale;
};

struct minmea_date {
    int day;
    int month;
    int year;
};

struct minmea_time {
    int hours;
    int minutes;
    int seconds;
    int microseconds;
};

struct minmea_sentence_gbs {
    struct minmea_time time;
    struct minmea_float err_latitude;
    struct minmea_float err_longitude;
    struct minmea_float err_altitude;
    int svid;
    struct minmea_float prob;
    struct minmea_float bias;
    struct minmea_float stddev;
};

struct minmea_sentence_rmc {
    struct minmea_time time;
    bool valid;
    struct minmea_float latitude;
    struct minmea_float longitude;
    struct minmea_float speed;
    struct minmea_float course;
    struct minmea_date date;
    struct minmea_float variation;
};

struct minmea_sentence_gga {
    struct minmea_time time;
    struct minmea_float latitude;
    struct minmea_float longitude;
    int fix_quality;
    int satellites_tracked;
    struct minmea_float hdop;
    struct minmea_float altitude; char altitude_units;
    struct minmea_float height; char height_units;
    struct minmea_float dgps_age;
};

enum minmea_gll_status {
    MINMEA_GLL_STATUS_DATA_VALID = 'A',
    MINMEA_GLL_STATUS_DATA_NOT_VALID = 'V',
};

// FAA mode added to some fields in NMEA 2.3.
enum minmea_faa_mode {
    MINMEA_FAA_MODE_AUTONOMOUS = 'A',
    MINMEA_FAA_MODE_DIFFERENTIAL = 'D',
    MINMEA_FAA_MODE_ESTIMATED = 'E',
    MINMEA_FAA_MODE_MANUAL = 'M',
    MINMEA_FAA_MODE_SIMULATED = 'S',
    MINMEA_FAA_MODE_NOT_VALID = 'N',
    MINMEA_FAA_MODE_PRECISE = 'P',
};

struct minmea_sentence_gll {
    struct minmea_float latitude;
    struct minmea_float longitude;
    struct minmea_time time;
    char status;
    char mode;
};

struct minmea_sentence_gst {
    struct minmea_time time;
    struct minmea_float rms_deviation;
    struct minmea_float semi_major_deviation;
    struct minmea_float semi_minor_deviation;
    struct minmea_float semi_major_orientation;
    struct minmea_float latitude_error_deviation;
    struct minmea_float longitude_error_deviation;
    struct minmea_float altitude_error_deviation;
};

enum minmea_gsa_mode {
    MINMEA_GPGSA_MODE_AUTO = 'A',
    MINMEA_GPGSA_MODE_FORCED = 'M',
};

enum minmea_gsa_fix_type {
    MINMEA_GPGSA_FIX_NONE = 1,
    MINMEA_GPGSA_FIX_2D = 2,
    MINMEA_GPGSA_FIX_3D = 3,
};

struct minmea_sentence_gsa {
    char mode;
    int fix_type;
    int sats[12];
    struct minmea_float pdop;
    struct minmea_float hdop;
    struct minmea_float vdop;
    int sysid;
};

struct minmea_sat_info {
    int nr;
    int elevation;
    int azimuth;
    int snr;
};

struct minmea_sentence_gsv {
    int total_msgs;
    int msg_nr;
    int total_sats;
    struct minmea_sat_info sats[4];
};

struct minmea_sentence_vtg {
    struct minmea_float true_track_degrees;
    struct minmea_float magnetic_track_degrees;
    struct minmea_float speed_knots;
    struct minmea_float speed_kph;
    enum minmea_faa_mode faa_mode;
};

struct minmea_sentence_zda {
    struct minmea_time time;
    struct minmea_date date;
    int hour_offset;
    int minute_offset;
};

struct minmea_sentence_txt {
    int count;
    int index;
    char txt[FRAME_TXT_MAX_LEN + 1];
};

/**
 * Calculate raw sentence checksum. Does not check sentence integrity.
 */
uint8_t minmea_checksum(const char *sentence);

/**
 * Check sentence validity and checksum. Returns true for valid sentences.
 */
bool minmea_check(const char *sentence, bool strict);

/**
 * Determine talker identifier.
 */
bool minmea_talker_id(char talker[3], const char *sentence);

/**
 * Determine sentence identifier.
 */
enum minmea_sentence_id minmea_sentence_id(const char *sentence, bool strict);

/**
 * Scanf-like processor for NMEA sentences. Supports the following formats:
 * c - single character (char *)
 * d - direction, returned as 1/-1, default 0 (int *)
 * f - fractional, returned as value + scale (struct minmea_float *)
 * i - decimal, default zero (int *)
 * s - string (char *)
 * t - talker identifier and type (char *)
 * D - date (struct minmea_date *)
 * T - time stamp (struct minmea_time *)
 * _ - ignore this field
 * ; - following fields are optional
 * Returns true on success. See library source code for details.
 */
bool minmea_scan(const char *sentence, const char *format, ...);

/*
 * Parse a specific type of sentence. Return true on success.
 */
bool minmea_parse_gbs(struct minmea_sentence_gbs *frame, const char *sentence);
bool minmea_parse_rmc(struct minmea_sentence_rmc *frame, const char *sentence);
bool minmea_parse_gga(struct minmea_sentence_gga *frame, const char *sentence);
bool minmea_parse_gsa(struct minmea_sentence_gsa *frame, const char *sentence);
bool minmea_parse_gll(struct minmea_sentence_gll *frame, const char *sentence);
bool minmea_parse_gst(struct minmea_sentence_gst *frame, const char *sentence);
bool minmea_parse_gsv(struct minmea_sentence_gsv *frame, const char *sentence);
bool minmea_parse_vtg(struct minmea_sentence_vtg *frame, const char *sentence);
bool minmea_parse_zda(struct minmea_sentence_zda *frame, const char *sentence);
bool minmea_parse_txt(struct minmea_sentence_txt *frame, const char *sentence);

/**
 * Convert GPS UTC date/time representation to a UNIX calendar time.
 */
int minmea_getdatetime(struct tm *tm, const struct minmea_date *date, const struct minmea_time *time_);

/**
 * Convert GPS UTC date/time representation to a UNIX timestamp.
 */
int minmea_gettime(struct timespec *ts, const struct minmea_date *date, const struct minmea_time *time_);

/**
 * Rescale a fixed-point value to a different scale. Rounds towards zero.
 */
static inline int_least32_t minmea_rescale(const struct minmea_float *f, int_least32_t new_scale)
{
    if (f->scale == 0)
        return 0;
    if (f->scale == new_scale)
        return f->value;
    if (f->scale > new_scale)
        return (f->value + ((f->value > 0) - (f->value < 0)) * f->scale/new_scale/2) / (f->scale/new_scale);
    else
        return f->value * (new_scale/f->scale);
}

/**
 * Convert a fixed-point value to a floating-point value.
 * Returns NaN for "unknown" values.
 */
static inline float minmea_tofloat(const struct minmea_float *f)
{
    if (f->scale == 0)
        return 0;
    return (float) f->value / (float) f->scale;
}

/**
 * Convert a raw coordinate to a floating point DD.DDD... value.
 * Returns NaN for "unknown" values.
 */
static inline float minmea_tocoord(const struct minmea_float *f)
{
    if (f->scale == 0)
        return 0;
    if (f->scale  > (INT_LEAST32_MAX / 100))
        return 0;
    if (f->scale < (INT_LEAST32_MIN / 100))
        return 0;
    int_least32_t degrees = f->value / (f->scale * 100);
    int_least32_t minutes = f->value % (f->scale * 100);
    return (float) degrees + (float) minutes / (60 * f->scale);
}

/**
 * Convert a raw coordinate to a floating point DD.DDD... value.
 * Returns NaN for "unknown" values.
 */
static inline uint32_t minmea_tocoord2(const struct minmea_float *f)
{
    if (f->scale == 0)
        return 0;
    if (f->scale  > (INT_LEAST32_MAX / 100))
        return 0;
    if (f->scale < (INT_LEAST32_MIN / 100))
        return 0;
    int_least32_t degrees = f->value / (f->scale * 100);
    int_least32_t minutes = f->value % (f->scale * 100);
    uint32_t ret = degrees * 10000000 + (uint32_t)(((float) minutes / (60 * f->scale)) * 10000000);
    return ret;
}

/**
 * Check whether a character belongs to the set of characters allowed in a
 * sentence data field.
 */
static inline bool minmea_isfield(char c) {
    return isprint((unsigned char) c) && c != ',' && c != '*';
}


// 扩展

#define RECV_BUFF_SIZE (2048)
#define FRAME_GSA_MAX   (7)
#define FRAME_GSV_MAX   (24)
#define FRAME_TXT_MAX   (80)


#define LUAT_LIBGNSS_MAX_LINE (128)

int luat_libgnss_init(int clear);
int luat_libgnss_parse_data(const char* data, size_t len);
int luat_libgnss_parse_nmea(const char* line);
void luat_libgnss_uart_recv_cb(int uart_id, uint32_t data_len);
int luat_libgnss_state_onchanged(int state);

int luat_libgnss_on_rawdata(const char* data, size_t len, int type);

enum GNSS_STATE {
    GNSS_STATE_INIT = 0,
    GNSS_STATE_FIXED,
    GNSS_STATE_LOSE,
    GNSS_STATE_OPEN,
    GNSS_STATE_CLOSE
};

// typedef union
// {
//     struct minmea_sentence_rmc frame_rmc;
//     struct minmea_sentence_gga frame_gga;
//     struct minmea_sentence_gll frame_gll;
//     struct minmea_sentence_gst frame_gst;
//     struct minmea_sentence_gsv frame_gsv;
//     struct minmea_sentence_vtg frame_vtg;
//     struct minmea_sentence_gsa frame_gsa;
//     struct minmea_sentence_zda frame_zda;
//     struct minmea_sentence_txt txt;
// }minmea_data_t;

typedef struct minmea_data {
    char data[LUAT_LIBGNSS_MAX_LINE];
    uint64_t tm;
}minmea_data_t;

typedef struct luat_libgnss
{
    uint32_t fix_at_ticks;
    struct minmea_sentence_rmc frame_rmc;
    minmea_data_t* rmc;
    minmea_data_t *gga;
    minmea_data_t *gll;
    minmea_data_t *gst;
    minmea_data_t *vtg;
    minmea_data_t *zda;
    minmea_data_t *gsv[FRAME_GSV_MAX];
    minmea_data_t *gsa[FRAME_GSA_MAX];
    minmea_data_t* txt;
    uint8_t debug;
    uint8_t rtc_auto;
    uint8_t gsa_offset;
} luat_libgnss_t;

int luat_libgnss_data_check(minmea_data_t* data, uint32_t timeout, uint64_t tnow);


#ifdef __cplusplus
}
#endif

#endif /* MINMEA_H */

/* vim: set ts=4 sw=4 et: */