/*
 * canbus_obd.h
 * OBD-II (ISO 15031) PID decoder over ISO-TP.
 */
#pragma once

#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>

#ifdef __cplusplus
extern "C" {
#endif

/* Standard OBD-II CAN IDs */
#define OBD_REQUEST_ID   0x7DF  /* Broadcast functional request */
#define OBD_RESPONSE_MIN 0x7E8
#define OBD_RESPONSE_MAX 0x7EF

/* Decoded PID result */
typedef struct {
    uint8_t     pid;
    float       value;
    const char *unit;   /* "rpm", "km/h", "C", etc. */
    const char *name;   /* "Engine RPM", "Vehicle Speed", etc. */
} obd_result_t;

/* Query a single PID (Mode 01). Returns 0 on success, -1 on error. */
int obd_query_pid(uint8_t mode, uint8_t pid, obd_result_t *out);

/* Query supported PIDs (Mode 01, PID 00/20/40/60). Returns count. */
int obd_query_supported(uint8_t pids_out[], int max_pids);

/* Read Vehicle Identification Number (Mode 09, PID 02). Returns 0 or -1. */
int obd_read_vin(char *vin_out, size_t cap);

/* Read Diagnostic Trouble Codes (Mode 03). Returns formatted string length. */
int obd_read_dtcs(char *dtc_buf, size_t cap);

/* Continuous monitoring: stream PIDs to C2 at interval */
void obd_monitor_start(const uint8_t *pids, int pid_count,
                       int interval_ms, const char *request_id);
void obd_monitor_stop(void);
bool obd_monitor_is_running(void);

#ifdef __cplusplus
}
#endif