#include <stdio.h>
#include <string.h>

#include "ql_gnss.h"
#include "ql_rtos.h"

#include "factory_gnss.h"

#define FT_GNSS_NMEA_GGA_GSV  ((1 << 0) | (1 << 2))

typedef struct {
    volatile int open_ret;
    volatile u32 nmea_count;
    volatile int sat_count;
    volatile int fix_status;
    volatile int started;
    u32 start_ms;
} factory_gnss_context_t;

static factory_gnss_context_t g_factory_gnss;

static u32 factory_gnss_now_ms(void)
{
    return ql_rtos_get_systicks() * 5U;
}

static int nmea_field_int(const char *line, int line_len, int wanted_field,
                          int *value)
{
    int field = 0;
    int i;
    int parsed = 0;
    int number = 0;

    for (i = 0; i < line_len; ++i) {
        char ch = line[i];
        if (ch == ',') {
            if (field == wanted_field) break;
            ++field;
            continue;
        }
        if (field == wanted_field) {
            if (ch < '0' || ch > '9') break;
            number = number * 10 + (ch - '0');
            parsed = 1;
        }
    }
    if (!parsed) return 0;
    *value = number;
    return 1;
}

static void factory_gnss_callback(char *data, int len)
{
    int i;

    if (!data || len <= 0) return;
    for (i = 0; i + 5 < len; ++i) {
        int line_end;
        int value;

        if (data[i] != '$') continue;
        ++g_factory_gnss.nmea_count;
        for (line_end = i; line_end < len; ++line_end) {
            if (data[line_end] == '\r' || data[line_end] == '\n') break;
        }
        if (data[i + 3] == 'G' && data[i + 4] == 'S' && data[i + 5] == 'V' &&
            nmea_field_int(data + i, line_end - i, 3, &value) &&
            value > g_factory_gnss.sat_count) {
            g_factory_gnss.sat_count = value;
        }
        if (data[i + 3] == 'G' && data[i + 4] == 'G' && data[i + 5] == 'A' &&
            nmea_field_int(data + i, line_end - i, 6, &value) &&
            value > g_factory_gnss.fix_status) {
            g_factory_gnss.fix_status = value;
        }
        i = line_end;
    }
}

void factory_gnss_start(void)
{
    int cfgsys_ret;
    int cfgmsg_ret;
    int mode_ret;

    memset(&g_factory_gnss, 0, sizeof(g_factory_gnss));
    g_factory_gnss.open_ret = -1;
    g_factory_gnss.start_ms = factory_gnss_now_ms();
    cfgsys_ret = ql_gnss_cfgsys_set(1);
    cfgmsg_ret = ql_gnss_cfgmsg_set(FT_GNSS_NMEA_GGA_GSV);
    mode_ret = ql_set_gnss_nmea_mode(PACKET_MODE);
    g_factory_gnss.open_ret = ql_gnss_open(factory_gnss_callback);
    g_factory_gnss.started = (g_factory_gnss.open_ret == 0);
    printf("[FT_GNSS] start open_ret=%d cfgsys_ret=%d cfgmsg_ret=%d mode_ret=%d\r\n",
           g_factory_gnss.open_ret, cfgsys_ret, cfgmsg_ret, mode_ret);
}

void factory_gnss_snapshot(factory_gnss_result_t *result)
{
    if (!result) return;
    result->open_ret = g_factory_gnss.open_ret;
    result->nmea_count = g_factory_gnss.nmea_count;
    result->sat_count = g_factory_gnss.sat_count;
    result->fix_status = g_factory_gnss.fix_status;
    result->search_ms = factory_gnss_now_ms() - g_factory_gnss.start_ms;
}

void factory_gnss_stop(void)
{
    int ret;
    if (!g_factory_gnss.started) return;
    ret = ql_gnss_close();
    g_factory_gnss.started = 0;
    printf("[FT_GNSS] stop ret=%d nmea=%lu sat=%d fix=%d\r\n", ret,
           (unsigned long)g_factory_gnss.nmea_count,
           g_factory_gnss.sat_count, g_factory_gnss.fix_status);
}