#include <assert.h>
#include <string.h>
#include <openssl/evp.h>
#include "utun_instance.h"
#include "routing_layer/topo_group.h"
#include "routing_layer/topo_node_sqlite.h"
#include "transport_layer/secure_channel.h"
#include "transport_layer/etcp.h"
#include "../lib/mem.h"
#include "../lib/memory_pool.h"
#include "../lib/u_async.h"
#include "../lib/debug_config.h"

static void sign_record(struct UTUN_INSTANCE* inst, struct TOPO_NODE* ni) {
    uint8_t msg[TOPO_SIG_MSG_MAX_SIZE];
    int len = topo_node_build_sig_msg(ni, msg, sizeof(msg));
    assert(len > 0);
    assert(sc_ed25519_sign(inst->my_ed25519_privkey, msg, (size_t)len, ni->x25519_self_sig) == SC_OK);
}

static struct TOPO_NODE* record(struct UTUN_INSTANCE* inst, uint64_t timestamp, const char* name, int address) {
    struct TOPO_NODE* ni = u_calloc(1, sizeof(*ni));
    assert(ni);
    ni->node_id = inst->node_id;
    ni->timestamp = timestamp;
    ni->node_name = u_strdup(name);
    memcpy(ni->public_key, inst->my_keys.public_key, 32);
    memcpy(ni->ed25519_public_key, inst->my_ed25519_pubkey, 32);
    if (address) {
        ni->v4_addrs = memory_pool_alloc(inst->topo_groups->v4_addr_pool);
        assert(ni->v4_addrs);
        *ni->v4_addrs = (struct TOPO_ADDR4){ .addr = {127,0,0,1}, .port = 9000, .protocol = TOPO_PROTO_UDP };
    }
    sign_record(inst, ni);
    return ni;
}

static void test_bgp(struct UTUN_INSTANCE* signer) {
    struct UTUN_INSTANCE receiver = { .ua = signer->ua, .topo_groups = signer->topo_groups };
    struct TOPO_GROUP group = { .instance = &receiver, .group_id = 10, .group_type = TOPO_GROUP_TYPE_CHAT };
    struct ETCP_CONN from = { .instance = &receiver, .peer_node_id = 7 };
    group.nodes = queue_new(receiver.ua, 16, 0, 8, "snapshot_bgp");
    struct TOPO_NODE* ni = record(signer, INT64_MAX - 7, "BGP", 1);
    from.peer_node_id = ni->node_id; from.links_up = 1;
    struct TOPO_GROUP_NODE nq = {0};
    uint8_t packet[4096] = {0};
    int len = topo_node_serialize(ni, &nq, group.group_id, 0, packet + sizeof(struct TOPOMSG_HEADER), sizeof(packet) - sizeof(struct TOPOMSG_HEADER), 0);
    assert(len > 0);
    assert(topo_group_process_nodeinfo(&group, &from, packet, (size_t)len + sizeof(struct TOPOMSG_HEADER)) == 0);
    struct TOPO_GROUP_NODE* peer = topo_node_find_by_id(&group, ni->node_id);
    assert(peer && peer->last_timestamp == ni->timestamp && queue_entry_count(peer->paths) == 1);
    assert(topo_group_process_nodeinfo(&group, &from, packet, (size_t)len + sizeof(struct TOPOMSG_HEADER)) == 0);
    assert(queue_entry_count(peer->paths) == 1);
    struct TOPOMSG_NODEINFO_PKT* wire = (struct TOPOMSG_NODEINFO_PKT*)packet;
    wire->node.timestamp++; /* подделка не удаляет узел и ранее принятый маршрут */
    assert(topo_group_process_nodeinfo(&group, &from, packet, (size_t)len + sizeof(struct TOPOMSG_HEADER)) < 0);
    assert(topo_node_find_by_id(&group, ni->node_id) == peer && queue_entry_count(peer->paths) == 1);
    wire->node.timestamp--;
    ni->timestamp--;
    sign_record(signer, ni);
    len = topo_node_serialize(ni, &nq, group.group_id, 0, packet + sizeof(struct TOPOMSG_HEADER), sizeof(packet) - sizeof(struct TOPOMSG_HEADER), 0);
    assert(topo_group_process_nodeinfo(&group, &from, packet, (size_t)len + sizeof(struct TOPOMSG_HEADER)) == 0);
    assert(peer->last_timestamp == INT64_MAX - 7 && queue_entry_count(peer->paths) == 1);
    topo_group_remove_path(peer, &from);
    topo_nodeq_remove_node(&group, peer);
    topo_node_destroy(signer->topo_groups, ni);
    queue_free(group.nodes);
}

int main(void) {
    debug_config_init();
    debug_set_level(DEBUG_LEVEL_DEBUG);
    struct UTUN_INSTANCE inst = {0};
    struct TOPO_GROUPS groups = { .instance = &inst };
    inst.topo_groups = &groups;
    inst.ua = uasync_create();
    assert(inst.ua);
    groups.node_registry = queue_new(inst.ua, 16, 0, 8, "snapshot_test");
    groups.v4_addr_pool = memory_pool_init(sizeof(struct TOPO_ADDR4), "snapshot_v4");
    assert(sc_generate_keypair(&inst.my_keys) == SC_OK);
    memcpy(inst.my_ed25519_privkey, inst.my_keys.private_key, 32);
    EVP_PKEY* key = EVP_PKEY_new_raw_private_key(EVP_PKEY_ED25519, NULL, inst.my_ed25519_privkey, 32);
    size_t key_len = 32;
    assert(key && EVP_PKEY_get_raw_public_key(key, inst.my_ed25519_pubkey, &key_len) == 1);
    EVP_PKEY_free(key);
    inst.node_id = sc_derive_node_id_from_pubkey(inst.my_keys.public_key);
    assert(sqlite3_open(":memory:", &inst.topo_sqlite_db) == SQLITE_OK);
    assert(topo_node_sqlite_init(inst.topo_sqlite_db) == 0);

    struct TOPO_NODE* first = record(&inst, 100, "old", 1);
    assert(topo_node_verify(first) == 0);
    first->timestamp++;
    assert(topo_node_verify(first) < 0); /* timestamp защищён подписью */
    first->timestamp--;
    assert(topo_node_registry_store(&groups, first) == first);
    struct TOPO_NODE* stale = record(&inst, 99, "stale", 0);
    assert(topo_node_registry_store(&groups, stale) == first);
    topo_node_registry_unref(&groups, inst.node_id);
    assert(first->timestamp == 100 && first->v4_addrs && !strcmp(first->node_name, "old"));

    struct TOPO_NODE* conflict = record(&inst, 100, "conflict", 0);
    assert(topo_node_registry_store(&groups, conflict) == first);
    topo_node_registry_unref(&groups, inst.node_id);
    assert(first->v4_addrs && !strcmp(first->node_name, "old"));

    assert(topo_node_sqlite_snapshot_put(inst.topo_sqlite_db, first) == 0);
    struct TOPO_NODE* loaded = topo_node_sqlite_snapshot_load(inst.topo_sqlite_db, &groups, inst.node_id);
    assert(loaded && loaded->timestamp == 100 && loaded->v4_addrs && topo_node_verify(loaded) == 0);
    topo_node_destroy(&groups, loaded);

    struct TOPO_NODE* fresh = record(&inst, 101, "new", 0);
    assert(topo_node_registry_store(&groups, fresh) == first);
    topo_node_registry_unref(&groups, inst.node_id);
    assert(first->timestamp == 101 && !first->v4_addrs && !strcmp(first->node_name, "new"));
    assert(topo_node_verify(first) == 0); /* удаление адресов не оставляет частей старой записи */
    assert(topo_node_sqlite_snapshot_put(inst.topo_sqlite_db, first) == 0);
    loaded = record(&inst, 100, "old", 1);
    assert(topo_node_sqlite_snapshot_put(inst.topo_sqlite_db, loaded) == 0);
    topo_node_destroy(&groups, loaded);
    loaded = topo_node_sqlite_snapshot_load(inst.topo_sqlite_db, &groups, inst.node_id);
    assert(loaded && loaded->timestamp == 101 && !loaded->v4_addrs && topo_node_verify(loaded) == 0);
    topo_node_destroy(&groups, loaded);

    /* Сохранённая версия из будущего: локальные часы/перезапуск не откатывают timestamp. */
    topo_node_registry_unref(&groups, inst.node_id);
    first = topo_node_registry_store(&groups, record(&inst, 99, "stale after restart", 1));
    assert(first && first->timestamp == 101 && !first->v4_addrs && topo_node_verify(first) == 0);
    first->timestamp = INT64_MAX - 10;
    sign_record(&inst, first);
    assert(topo_node_sqlite_snapshot_put(inst.topo_sqlite_db, first) == 0);
    first->timestamp = 0;
    assert(topo_node_sign_self(&inst, first) == 0);
    assert(first->timestamp == INT64_MAX - 9 && topo_node_verify(first) == 0);
    assert(topo_node_sign_self(&inst, first) == 0);
    assert(first->timestamp == INT64_MAX - 8 && topo_node_verify(first) == 0);
    test_bgp(&inst);
    uint64_t before = first->timestamp;
    assert(sqlite3_exec(inst.topo_sqlite_db,
        "CREATE TRIGGER fail_snapshot BEFORE UPDATE ON node_snapshots BEGIN SELECT RAISE(ABORT,'test write failure'); END",
        NULL, NULL, NULL) == SQLITE_OK);
    assert(topo_node_sign_self(&inst, first) < 0);
    assert(first->timestamp == before && topo_node_verify(first) == 0);

    topo_node_registry_unref(&groups, inst.node_id);
    assert(!groups.node_registry->head);
    queue_free(groups.node_registry);
    memory_pool_destroy(groups.v4_addr_pool);
    sqlite3_close(inst.topo_sqlite_db);
    uasync_destroy(inst.ua, 0);
    return 0;
}