/*
 * gps_sync.h
 *
 * Copyright (c) 2025 Umber Networks & Robert McMahon
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. 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.
 *
 * 3. Neither the name of the copyright holder 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.
 */

#pragma once

#include <stdint.h>
#include <stdbool.h>
#include "esp_err.h"
#include "driver/uart.h"
#include "driver/gpio.h"

#ifdef __cplusplus
extern "C" {
#endif

// --- Configuration Struct ---
typedef struct {
    uart_port_t uart_port;
    gpio_num_t tx_pin;
    gpio_num_t rx_pin;
    gpio_num_t pps_pin;
} gps_sync_config_t;

// --- Timestamp Struct ---
typedef struct {
    int64_t gps_us;  // Current GPS time in microseconds
    bool synced;     // PPS signal is active and stable (Precision Lock)
    bool valid;      // NMEA data indicates valid fix ('A' status) (Data Lock)
} gps_timestamp_t;

// --- Initialization ---
// Initializes the GPS task with specific hardware pins
void gps_sync_init(const gps_sync_config_t *cfg, bool force_enable);

// --- Getters ---
gps_timestamp_t gps_get_timestamp(void);

// Returns milliseconds since the last PPS edge (Diagnostic)
int64_t gps_get_pps_age_ms(void);

// Copies the last received NMEA line into buffer (Diagnostic)
void gps_get_last_nmea(char *buf, size_t buf_len);

#ifdef __cplusplus
}
#endif