/* Unit tests for the connectivity-probe helpers in hbc_mini.c.
 * Build and run:  make test        (live check of this host:  ./test_probe --live)
 * The source file is included directly so its static functions can be exercised; its main()
 * is renamed out of the way.
 */
#define main hbc_mini_main
#include "hbc_mini.c"
#undef main

static int g_run = 0, g_fail = 0;
#define CHECK(cond) do { g_run++; if (!(cond)) { g_fail++; \
    fprintf(stderr, "FAIL %s:%d: %s\n", __FILE__, __LINE__, #cond); } } while (0)
#define CHECK_STR(a, b) do { g_run++; if (strcmp((a), (b)) != 0) { g_fail++; \
    fprintf(stderr, "FAIL %s:%d: \"%s\" != \"%s\"\n", __FILE__, __LINE__, (a), (b)); } } while (0)

static const char PROC_V4[] =
    "Iface\tDestination\tGateway \tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU\tWindow\tIRTT\n"
    "wlan0\t00000000\t0100A8C0\t0003\t0\t0\t600\t00000000\t0\t0\t0\n"
    "eth0\t00000000\t0101A8C0\t0003\t0\t0\t100\t00000000\t0\t0\t0\n"
    "wlan0\t0000A8C0\t00000000\t0001\t0\t0\t600\t00FFFFFF\t0\t0\t0\n";

static const char PROC_V6[] =
    "00000000000000000000000000000000 00 00000000000000000000000000000000 00 "
    "fe800000000000000000000000000001 00000400 00000001 00000000 00000003 wlan0\n"
    "00000000000000000000000000000000 00 00000000000000000000000000000000 00 "
    "00000000000000000000000000000000 ffffffff 00000001 00000000 00200200 lo\n"
    "fe800000000000000000000000000000 40 00000000000000000000000000000000 00 "
    "00000000000000000000000000000000 00000100 00000001 00000000 00000001 wlan0\n";

static const char ROUTE_GET[] =
    "   route to: 0.0.0.0\ndestination: 0.0.0.0\n       mask: 0.0.0.0\n"
    "    gateway: 192.0.2.1\n        fib: 0\n  interface: vtnet0\n";

static const char LINUX_PING[] =
    "PING 1.1.1.1 (1.1.1.1) 56(84) bytes of data.\n"
    "64 bytes from 1.1.1.1: icmp_seq=1 ttl=57 time=11.2 ms\n\n"
    "--- 1.1.1.1 ping statistics ---\n"
    "1 packets transmitted, 1 received, 0% packet loss, time 0ms\n"
    "rtt min/avg/max/mdev = 11.234/11.234/11.234/0.000 ms\n";

static const char FREEBSD_PING[] =
    "PING 1.1.1.1 (1.1.1.1): 56 data bytes\n"
    "64 bytes from 1.1.1.1: icmp_seq=0 ttl=59 time=4.006 ms\n\n"
    "--- 1.1.1.1 ping statistics ---\n"
    "1 packets transmitted, 1 packets received, 0.0% packet loss, 1 packets out of wait time\n"
    "round-trip min/avg/max/stddev = 4.006/4.006/4.006/0.000 ms\n";

static void test_gateway_parsers(void) {
    char gw[64];
    gw_parse_proc_v4(PROC_V4, gw, sizeof(gw));
    CHECK_STR(gw, "192.168.1.1");                    /* eth0, metric 100 beats wlan0, 600 */
    gw_parse_proc_v4("Iface\tDestination\n", gw, sizeof(gw));
    CHECK_STR(gw, "");
    gw_parse_proc_v6(PROC_V6, gw, sizeof(gw));
    CHECK_STR(gw, "fe80::1");                        /* reject and non-default lines skipped */
    gw_parse_route_get(ROUTE_GET, gw, sizeof(gw));
    CHECK_STR(gw, "192.0.2.1");
    gw_parse_route_get("route: writing to routing socket: not in table\n", gw, sizeof(gw));
    CHECK_STR(gw, "");
}

static void test_ping_parser(void) {
    CHECK(ping_parse_rtt(LINUX_PING) > 11.23 && ping_parse_rtt(LINUX_PING) < 11.24);
    CHECK(ping_parse_rtt(FREEBSD_PING) > 4.0 && ping_parse_rtt(FREEBSD_PING) < 4.01);
    CHECK(ping_parse_rtt("1 packets transmitted, 0 received, 100% packet loss\n") == -1.0);
    CHECK(ping_parse_rtt("sh: 1: ping: not found\n") == -2.0);
    CHECK(ping_parse_rtt("ping: command not found\n") == -2.0);
}

/* ---- scriptable network for probe_step ------------------------------------------------ */
static struct {
    char   addr[2][INET6_ADDRSTRLEN];   /* "" = no route */
    char   gw[2][INET6_ADDRSTRLEN];
    double rtt[2];                      /* -1 no reply, -2 ping unavailable */
    int    unsupported[2];
    int    npings[2];
} net;

static int fake_local(int af, const char *t, char *out, size_t n) {
    int f = af == AF_INET6; (void)t;
    if (net.unsupported[f]) return -1;
    if (!net.addr[f][0]) return 0;
    snprintf(out, n, "%s", net.addr[f]);
    return 1;
}
static double fake_ping(int af, const char *t) { int f = af == AF_INET6; (void)t; net.npings[f]++; return net.rtt[f]; }
static void fake_gw(int af, char *out, size_t n) { snprintf(out, n, "%s", net.gw[af == AF_INET6]); }
static const probe_ops_t FAKE = { fake_local, fake_ping, fake_gw };

static void net_reset(void) {
    memset(&net, 0, sizeof(net));
    snprintf(net.addr[0], INET6_ADDRSTRLEN, "192.0.2.5");
    snprintf(net.addr[1], INET6_ADDRSTRLEN, "2001:db8::5");
    snprintf(net.gw[0], INET6_ADDRSTRLEN, "192.0.2.1");
    snprintf(net.gw[1], INET6_ADDRSTRLEN, "fe80::1");
    net.rtt[0] = 10.0; net.rtt[1] = 20.0;
}

static void probe_reset(probe_t *p) {
    memset(p, 0, sizeof(*p));
    snprintf(p->target[0], sizeof(p->target[0]), "1.1.1.1");
    snprintf(p->target[1], sizeof(p->target[1]), "2606:4700:4700::1111");
    p->probe_interval = 60; p->retry_interval = 10; p->cheap_gateway = true;
    p->fam[0].present = p->fam[1].present = PROBE_UNKNOWN;
    p->fam[0].rtt = p->fam[1].rtt = -1;
    pthread_mutex_init(&p->mu, NULL);
}

static void step_both(probe_t *p, double now) {
    probe_step(p, &p->fam[0], 0, &FAKE, now);
    probe_step(p, &p->fam[1], 1, &FAKE, now);
}

static void test_present_with_details(void) {
    net_reset(); probe_t p; probe_reset(&p);
    step_both(&p, 1000);
    CHECK(p.fam[0].present == 1 && p.fam[1].present == 1);
    CHECK_STR(p.fam[0].addr, "192.0.2.5");
    CHECK_STR(p.fam[0].gateway, "192.0.2.1");
    CHECK(p.fam[0].rtt == 10.0);
    kvdict_t d; kv_clear(&d);
    probe_flags(&p, &d);
    CHECK_STR(kv_get(&d, "p4") ? kv_get(&d, "p4") : "(null)", "1");
    CHECK_STR(kv_get(&d, "p6") ? kv_get(&d, "p6") : "(null)", "1");
    char js[512];
    CHECK(probe_metric_json(&p, js, sizeof(js)) > 0);
    CHECK(strstr(js, "\"ipv6\":{\"present\":true,\"addr\":\"2001:db8::5\",\"gateway\":\"fe80::1\"") != NULL);
}

static void test_no_route_is_absent_and_wastes_no_ping(void) {
    net_reset(); net.addr[1][0] = '\0'; probe_t p; probe_reset(&p);
    step_both(&p, 1000);
    CHECK(p.fam[1].present == 0 && net.npings[1] == 0 && net.npings[0] == 1);
    kvdict_t d; kv_clear(&d);
    probe_flags(&p, &d);
    CHECK_STR(kv_get(&d, "p6") ? kv_get(&d, "p6") : "(null)", "0");
    char js[512];
    probe_metric_json(&p, js, sizeof(js));
    CHECK(strstr(js, "\"ipv6\":{\"present\":false,\"addr\":null,\"gateway\":null,\"rtt\":null}") != NULL);
}

static void test_debounce_and_rate_limit(void) {
    net_reset(); probe_t p; probe_reset(&p);
    step_both(&p, 1000);
    step_both(&p, 1000);                                  /* cached: no second ping */
    CHECK(net.npings[0] == 1 && net.npings[1] == 1);
    net.rtt[1] = -1;
    step_both(&p, 1060);                                  /* first failure: still present */
    CHECK(p.fam[1].present == 1);
    step_both(&p, 1070);                                  /* retry interval elapsed: flips */
    CHECK(p.fam[1].present == 0);
    net.rtt[1] = 25;
    step_both(&p, 1080);                                  /* first success recovers */
    CHECK(p.fam[1].present == 1);
}

static void test_first_failure_is_unknown_and_omitted(void) {
    net_reset(); net.rtt[0] = -1; probe_t p; probe_reset(&p);
    step_both(&p, 1000);
    CHECK(p.fam[0].present == PROBE_UNKNOWN);
    kvdict_t d; kv_clear(&d);
    probe_flags(&p, &d);
    CHECK(kv_get(&d, "p4") == NULL && kv_get(&d, "p6") != NULL);
    char js[512];
    probe_metric_json(&p, js, sizeof(js));
    CHECK(strstr(js, "\"ipv4\":{\"present\":null") != NULL);
}

static void test_address_or_gateway_change_repings(void) {
    net_reset(); probe_t p; probe_reset(&p);
    step_both(&p, 1000);
    snprintf(net.addr[0], INET6_ADDRSTRLEN, "198.51.100.7");
    step_both(&p, 1000);
    CHECK(net.npings[0] == 2);
    snprintf(net.gw[0], INET6_ADDRSTRLEN, "192.0.2.254");
    step_both(&p, 1000);
    CHECK(net.npings[0] == 3);
}

static void test_route_loss_then_return_pings_immediately(void) {
    net_reset(); probe_t p; probe_reset(&p);
    step_both(&p, 1000);
    net.addr[1][0] = '\0';
    step_both(&p, 1000);
    CHECK(p.fam[1].present == 0);
    snprintf(net.addr[1], INET6_ADDRSTRLEN, "2001:db8::5");
    step_both(&p, 1000);
    CHECK(net.npings[1] == 2 && p.fam[1].present == 1);
}

static void test_missing_ping_stays_unknown_even_after_route_loss(void) {
    net_reset(); net.rtt[0] = -2; probe_t p; probe_reset(&p);
    step_both(&p, 1000);
    step_both(&p, 1600);
    CHECK(p.fam[0].present == PROBE_UNKNOWN && net.npings[0] == 1);
    net.addr[0][0] = '\0';
    step_both(&p, 1700);
    CHECK(p.fam[0].present == 0);                         /* no route is definitive */
    snprintf(net.addr[0], INET6_ADDRSTRLEN, "192.0.2.5");
    step_both(&p, 1800);
    CHECK(p.fam[0].present == PROBE_UNKNOWN && net.npings[0] == 1);
}

static void test_unsupported_family_is_unknown(void) {
    net_reset(); net.unsupported[1] = 1; probe_t p; probe_reset(&p);
    step_both(&p, 1000);
    CHECK(p.fam[1].present == PROBE_UNKNOWN && p.fam[0].present == 1);
}

static int live_mode(void) {
    static const probe_ops_t sys_ops = { sys_local_address, sys_ping, sys_gateway };
    probe_t p; probe_reset(&p);
    p.cheap_gateway = false;
    snprintf(p.target[0], sizeof(p.target[0]), "1.1.1.1");
    for (int round = 0; round < 3; round++) {
        double now = mono_ts();
        for (int f = 0; f < 2; f++) probe_step(&p, &p.fam[f], f, &sys_ops, now);
        sleep(round < 2 ? 11 : 0);
    }
    char js[512];
    probe_metric_json(&p, js, sizeof(js));
    kvdict_t d; kv_clear(&d);
    probe_flags(&p, &d);
    printf("%s\np4=%s p6=%s\n", js, kv_get(&d, "p4") ? kv_get(&d, "p4") : "-",
           kv_get(&d, "p6") ? kv_get(&d, "p6") : "-");
    return 0;
}

int main(int argc, char **argv) {
    if (argc > 1 && !strcmp(argv[1], "--live")) return live_mode();
    test_gateway_parsers();
    test_ping_parser();
    test_present_with_details();
    test_no_route_is_absent_and_wastes_no_ping();
    test_debounce_and_rate_limit();
    test_first_failure_is_unknown_and_omitted();
    test_address_or_gateway_change_repings();
    test_route_loss_then_return_pings_immediately();
    test_missing_ping_stays_unknown_even_after_route_loss();
    test_unsupported_family_is_unknown();
    printf("%d checks, %d failed\n", g_run, g_fail);
    return g_fail ? 1 : 0;
}