/**
 * @file
 * @brief command line tool that sends a BACnet Who-Is request to devices,
 * and prints any I-Am responses received.  This is useful for finding
 * devices on a network, or for finding devices that are in a specific
 * instance range.
 * @author Steve Karg <skarg@users.sourceforge.net>
 * @date 2006
 * @copyright SPDX-License-Identifier: MIT
 */
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
/* BACnet Stack defines - first */
#include "bacnet/bacdef.h"
/* BACnet Stack API */
#include "bacnet/bactext.h"
#include "bacnet/iam.h"
#include "bacnet/npdu.h"
#include "bacnet/apdu.h"
#include "bacnet/bactext.h"
#include "bacnet/version.h"
/* some demo stuff needed */
#include "bacnet/basic/binding/address.h"
#include "bacnet/basic/sys/mstimer.h"
#include "bacnet/basic/sys/filename.h"
#include "bacnet/basic/services.h"
#include "bacnet/basic/tsm/tsm.h"
#include "bacnet/basic/object/device.h"
#include "bacnet/datalink/datalink.h"
#include "bacnet/datalink/dlenv.h"
#include "bacport.h"

/* buffer used for receive */
static uint8_t Rx_Buf[MAX_MPDU] = { 0 };

/* global variables used in this file */
static int32_t Target_Object_Instance_Min = -1;
static int32_t Target_Object_Instance_Max = -1;
static bool Error_Detected = false;
/* debug info printing */
static bool BACnet_Debug_Enabled;

#define BAC_ADDRESS_MULT 1

struct address_entry {
    struct address_entry *next;
    uint8_t Flags;
    uint32_t device_id;
    unsigned max_apdu;
    BACNET_ADDRESS address;
};

static struct address_table {
    struct address_entry *first;
    struct address_entry *last;
} Address_Table = { 0 };

static struct address_entry *alloc_address_entry(void)
{
    struct address_entry *rval;
    rval = (struct address_entry *)calloc(1, sizeof(struct address_entry));
    if (Address_Table.first == 0) {
        Address_Table.first = Address_Table.last = rval;
    } else {
        Address_Table.last->next = rval;
        Address_Table.last = rval;
    }
    return rval;
}

static void address_table_add(
    uint32_t device_id, unsigned max_apdu, const BACNET_ADDRESS *src)
{
    struct address_entry *pMatch;
    uint8_t flags = 0;

    pMatch = Address_Table.first;
    while (pMatch) {
        if (pMatch->device_id == device_id) {
            if (bacnet_address_same(&pMatch->address, src)) {
                return;
            }
            flags |= BAC_ADDRESS_MULT;
            pMatch->Flags |= BAC_ADDRESS_MULT;
        }
        pMatch = pMatch->next;
    }

    pMatch = alloc_address_entry();

    pMatch->Flags = flags;
    pMatch->device_id = device_id;
    pMatch->max_apdu = max_apdu;
    pMatch->address = *src;

    return;
}

static void my_i_am_handler(
    uint8_t *service_request, uint16_t service_len, BACNET_ADDRESS *src)
{
    int len = 0;
    uint32_t device_id = 0;
    unsigned max_apdu = 0;
    int segmentation = 0;
    uint16_t vendor_id = 0;
    unsigned i = 0;

    len = bacnet_iam_request_decode(
        service_request, service_len, &device_id, &max_apdu, &segmentation,
        &vendor_id);
    if (BACnet_Debug_Enabled) {
        fprintf(stderr, "Received I-Am Request");
    }
    if (len != -1) {
        if (BACnet_Debug_Enabled) {
            fprintf(stderr, " from %lu, MAC = ", (unsigned long)device_id);
            if ((src->mac_len == 6) && (src->len == 0)) {
                fprintf(
                    stderr, "%u.%u.%u.%u %02X%02X\n", (unsigned)src->mac[0],
                    (unsigned)src->mac[1], (unsigned)src->mac[2],
                    (unsigned)src->mac[3], (unsigned)src->mac[4],
                    (unsigned)src->mac[5]);
            } else {
                for (i = 0; i < src->mac_len; i++) {
                    fprintf(stderr, "%02X", (unsigned)src->mac[i]);
                    if (i < (src->mac_len - 1)) {
                        fprintf(stderr, ":");
                    }
                }
                fprintf(stderr, "\n");
            }
        }
        address_table_add(device_id, max_apdu, src);
    } else {
        if (BACnet_Debug_Enabled) {
            fprintf(stderr, ", but unable to decode it.\n");
        }
    }

    return;
}

static void MyAbortHandler(
    BACNET_ADDRESS *src, uint8_t invoke_id, uint8_t abort_reason, bool server)
{
    /* FIXME: verify src and invoke id */
    (void)src;
    (void)invoke_id;
    (void)server;
    fprintf(
        stderr, "BACnet Abort: %s\n", bactext_abort_reason_name(abort_reason));
    Error_Detected = true;
}

static void
MyRejectHandler(BACNET_ADDRESS *src, uint8_t invoke_id, uint8_t reject_reason)
{
    /* FIXME: verify src and invoke id */
    (void)src;
    (void)invoke_id;
    fprintf(
        stderr, "BACnet Reject: %s\n",
        bactext_reject_reason_name(reject_reason));
    Error_Detected = true;
}

static void init_service_handlers(void)
{
    Device_Init(NULL);
    /* Note: this applications doesn't need to handle who-is
       it is confusing for the user! */
    /* set the handler for all the services we don't implement
       It is required to send the proper reject message... */
    apdu_set_unrecognized_service_handler_handler(handler_unrecognized_service);
    /* we must implement read property - it's required! */
    apdu_set_confirmed_handler(
        SERVICE_CONFIRMED_READ_PROPERTY, handler_read_property);
    /* handle the reply (request) coming back */
    apdu_set_unconfirmed_handler(SERVICE_UNCONFIRMED_I_AM, my_i_am_handler);
    /* handle any Who-Am-I requests we receive */
    apdu_set_unconfirmed_handler(
        SERVICE_UNCONFIRMED_WHO_AM_I, handler_who_am_i_json_print);
    /* handle any errors coming back */
    apdu_set_abort_handler(MyAbortHandler);
    apdu_set_reject_handler(MyRejectHandler);
}

static void print_macaddr(const uint8_t *addr, int len)
{
    int j = 0;

    while (j < len) {
        if (j != 0) {
            printf(":");
        }
        printf("%02X", addr[j]);
        j++;
    }
    while (j < MAX_MAC_LEN) {
        printf("   ");
        j++;
    }
}

static void print_address_cache(void)
{
    BACNET_ADDRESS address;
    unsigned total_addresses = 0;
    unsigned dup_addresses = 0;
    struct address_entry *addr;
    uint8_t local_sadr = 0;

    /*  NOTE: this string format is parsed by src/address.c,
       so these must be compatible. */

    printf(
        ";%-7s  %-20s %-5s %-20s %-4s\n", "Device", "MAC (hex)", "SNET",
        "SADR (hex)", "APDU");
    printf(";-------- -------------------- ----- -------------------- ----\n");

    addr = Address_Table.first;
    while (addr) {
        bacnet_address_copy(&address, &addr->address);
        total_addresses++;
        if (addr->Flags & BAC_ADDRESS_MULT) {
            dup_addresses++;
            printf(";");
        } else {
            printf(" ");
        }
        printf(" %-7u ", addr->device_id);
        print_macaddr(address.mac, address.mac_len);
        printf(" %-5hu ", address.net);
        if (address.net) {
            print_macaddr(address.adr, address.len);
        } else {
            print_macaddr(&local_sadr, 1);
        }
        printf(" %-4u ", (unsigned)addr->max_apdu);
        printf("\n");

        addr = addr->next;
    }
    printf(";\n; Total Devices: %u\n", total_addresses);
    if (dup_addresses) {
        printf("; * Duplicate Devices: %u\n", dup_addresses);
    }
}

static void print_usage(const char *filename)
{
    printf("Usage: %s", filename);
    printf(" [device-instance-min [device-instance-max]]\n");
    printf("       [--dnet][--dadr][--mac]\n");
    printf("       [--version][--help]\n");
}

static void print_help(const char *filename)
{
    printf("Send BACnet WhoIs service request to a device or multiple\n"
           "devices, and wait for responses. Displays any devices found\n"
           "and their network information.\n");
    printf("\n");
    printf("device-instance:\n"
           "BACnet Device Object Instance number that you are trying\n"
           "to send a Who-Is service request. The value should be in\n"
           "the range of 0 to 4194303. A range of values can also be\n"
           "specified by using a minimum value and a maximum value.\n");
    printf("\n");
    printf("--mac A\n"
           "BACnet mac address."
           "Valid ranges are from 00 to FF (hex) for MS/TP or ARCNET,\n"
           "or an IP string with optional port number like 10.1.2.3:47808\n"
           "or an Ethernet MAC in hex like 00:21:70:7e:32:bb\n");
    printf("\n");
    printf("--dnet N\n"
           "BACnet network number N for directed requests.\n"
           "Valid range is from 0 to 65535 where 0 is the local connection\n"
           "and 65535 is network broadcast.\n");
    printf("\n");
    printf("--dadr A\n"
           "BACnet mac address on the destination BACnet network number.\n"
           "Valid ranges are from 00 to FF (hex) for MS/TP or ARCNET,\n"
           "or an IP string with optional port number like 10.1.2.3:47808\n"
           "or an Ethernet MAC in hex like 00:21:70:7e:32:bb\n");
    printf("\n");
    printf("--repeat\n"
           "Send the message repeatedly until signalled to quit.\n"
           "Default is disabled, using the APDU timeout as time to quit.\n");
    printf("\n");
    printf("--retry C\n"
           "Send the message C number of times\n"
           "Default is retry 0, only sending one time.\n");
    printf("\n");
    printf("--timeout T\n"
           "Wait T milliseconds after sending before retry\n"
           "Default delay is 3000ms.\n");
    printf("\n");
    printf("--delay M\n"
           "Wait M milliseconds for responses after sending\n"
           "Default delay is 100ms.\n");
    printf("\n");
    printf("Example:\n");
    printf(
        "Send a WhoIs request to DNET 123:\n"
        "%s --dnet 123\n",
        filename);
    printf(
        "Send a WhoIs request to MAC 10.0.0.1 DNET 123 DADR 05h:\n"
        "%s --mac 10.0.0.1 --dnet 123 --dadr 05\n",
        filename);
    printf(
        "Send a WhoIs request to MAC 10.1.2.3:47808:\n"
        "%s --mac 10.1.2.3:47808\n",
        filename);
    printf(
        "Send a WhoIs request to Device 123:\n"
        "%s 123\n",
        filename);
    printf(
        "Send a WhoIs request to Devices from 1000 to 9000:\n"
        "%s 1000 9000\n",
        filename);
    printf(
        "Send a WhoIs request to Devices from 1000 to 9000 on DNET 123:\n"
        "%s 1000 9000 --dnet 123\n",
        filename);
    printf(
        "Send a WhoIs request to all devices:\n"
        "%s\n",
        filename);
}

int main(int argc, char *argv[])
{
    BACNET_ADDRESS src = { 0 }; /* address where message came from */
    uint16_t pdu_len = 0;
    unsigned timeout_milliseconds = 0;
    unsigned delay_milliseconds = 100;
    struct mstimer apdu_timer = { 0 };
    struct mstimer datalink_timer = { 0 };
    long dnet = -1;
    BACNET_MAC_ADDRESS mac = { 0 };
    BACNET_MAC_ADDRESS adr = { 0 };
    BACNET_ADDRESS dest = { 0 };
    bool global_broadcast = true;
    int argi = 0;
    unsigned int target_args = 0;
    const char *filename = NULL;
    bool repeat_forever = false;
    long retry_count = 0;

    /* check for local environment settings */
    if (getenv("BACNET_DEBUG")) {
        BACnet_Debug_Enabled = true;
    }
    /* decode any command line parameters */
    filename = filename_remove_path(argv[0]);
    for (argi = 1; argi < argc; argi++) {
        if (strcmp(argv[argi], "--help") == 0) {
            print_usage(filename);
            print_help(filename);
            return 0;
        }
        if (strcmp(argv[argi], "--version") == 0) {
            printf("%s %s\n", filename, BACNET_VERSION_TEXT);
            printf("Copyright (C) 2014 by Steve Karg and others.\n"
                   "This is free software; see the source for copying "
                   "conditions.\n"
                   "There is NO warranty; not even for MERCHANTABILITY or\n"
                   "FITNESS FOR A PARTICULAR PURPOSE.\n");
            return 0;
        }
        if (strcmp(argv[argi], "--mac") == 0) {
            if (++argi < argc) {
                if (bacnet_address_mac_from_ascii(&mac, argv[argi])) {
                    global_broadcast = false;
                }
            }
        } else if (strcmp(argv[argi], "--dnet") == 0) {
            if (++argi < argc) {
                if (!bacnet_strtol(argv[argi], &dnet)) {
                    fprintf(stderr, "dnet=%s invalid\n", argv[argi]);
                    return 1;
                }
                if ((dnet >= 0) && (dnet <= BACNET_BROADCAST_NETWORK)) {
                    global_broadcast = false;
                }
            }
        } else if (strcmp(argv[argi], "--dadr") == 0) {
            if (++argi < argc) {
                if (bacnet_address_mac_from_ascii(&adr, argv[argi])) {
                    global_broadcast = false;
                }
            }
        } else if (strcmp(argv[argi], "--repeat") == 0) {
            repeat_forever = true;
        } else if (strcmp(argv[argi], "--retry") == 0) {
            if (++argi < argc) {
                retry_count = strtol(argv[argi], NULL, 0);
                if (retry_count < 0) {
                    retry_count = 0;
                }
            }
        } else if (strcmp(argv[argi], "--timeout") == 0) {
            if (++argi < argc) {
                timeout_milliseconds = strtol(argv[argi], NULL, 0);
            }
        } else if (strcmp(argv[argi], "--delay") == 0) {
            if (++argi < argc) {
                delay_milliseconds = strtol(argv[argi], NULL, 0);
            }
        } else {
            if (target_args == 0) {
                Target_Object_Instance_Min = Target_Object_Instance_Max =
                    strtol(argv[argi], NULL, 0);
                target_args++;
            } else if (target_args == 1) {
                Target_Object_Instance_Max = strtol(argv[argi], NULL, 0);
                target_args++;
            } else {
                print_usage(filename);
                return 1;
            }
        }
    }
    if (global_broadcast) {
        datalink_get_broadcast_address(&dest);
    } else {
        if (adr.len && mac.len) {
            memcpy(&dest.mac[0], &mac.adr[0], mac.len);
            dest.mac_len = mac.len;
            memcpy(&dest.adr[0], &adr.adr[0], adr.len);
            dest.len = adr.len;
            if ((dnet >= 0) && (dnet <= BACNET_BROADCAST_NETWORK)) {
                dest.net = dnet;
            } else {
                dest.net = BACNET_BROADCAST_NETWORK;
            }
        } else if (mac.len) {
            memcpy(&dest.mac[0], &mac.adr[0], mac.len);
            dest.mac_len = mac.len;
            dest.len = 0;
            if ((dnet >= 0) && (dnet <= BACNET_BROADCAST_NETWORK)) {
                dest.net = dnet;
            } else {
                dest.net = 0;
            }
        } else {
            if ((dnet >= 0) && (dnet <= BACNET_BROADCAST_NETWORK)) {
                dest.net = dnet;
            } else {
                dest.net = BACNET_BROADCAST_NETWORK;
            }
            dest.mac_len = 0;
            dest.len = 0;
        }
    }
    if (Target_Object_Instance_Min > BACNET_MAX_INSTANCE) {
        fprintf(
            stderr, "device-instance-min=%u - not greater than %u\n",
            Target_Object_Instance_Min, BACNET_MAX_INSTANCE);
        return 1;
    }
    if (Target_Object_Instance_Max > BACNET_MAX_INSTANCE) {
        fprintf(
            stderr, "device-instance-max=%u - not greater than %u\n",
            Target_Object_Instance_Max, BACNET_MAX_INSTANCE);
        return 1;
    }
    /* setup my info */
    Device_Set_Object_Instance_Number(BACNET_MAX_INSTANCE);
    init_service_handlers();
    address_init();
    dlenv_init();
    atexit(datalink_cleanup);
    if (timeout_milliseconds == 0) {
        timeout_milliseconds = apdu_timeout() * apdu_retries();
    }
    mstimer_set(&apdu_timer, timeout_milliseconds);
    mstimer_set(&datalink_timer, 1000);
    /* send the request */
    Send_WhoIs_To_Network(
        &dest, Target_Object_Instance_Min, Target_Object_Instance_Max);
    if (retry_count > 0) {
        retry_count--;
    }
    /* loop forever */
    for (;;) {
        /* returns 0 bytes on timeout */
        pdu_len =
            datalink_receive(&src, &Rx_Buf[0], MAX_MPDU, delay_milliseconds);
        /* process */
        if (pdu_len) {
            npdu_handler(&src, &Rx_Buf[0], pdu_len);
        }
        if (Error_Detected) {
            break;
        }
        if (mstimer_expired(&datalink_timer)) {
            datalink_maintenance_timer(
                mstimer_interval(&datalink_timer) / 1000);
            mstimer_reset(&datalink_timer);
        }
        if (mstimer_expired(&apdu_timer)) {
            if (repeat_forever || retry_count) {
                Send_WhoIs_To_Network(
                    &dest, Target_Object_Instance_Min,
                    Target_Object_Instance_Max);
                retry_count--;
            } else {
                break;
            }
            mstimer_reset(&apdu_timer);
        }
    }
    print_address_cache();

    return 0;
}