voice-cat/server/src/conn_session.cpp

#include "conn_session.h"

#ifdef VOICECAT_HAS_NET

#include <algorithm>
#include <chrono>
#include <cstdio>
#include <cstring>

#include <sodium.h>

#include "db.h"
#include "session_registry.h"
#include "core/worker_pool.h"
#include "protocol/envelope.h"

namespace voicecat::server {

static voicecat::v1::Envelope make_env(uint64_t req_id = 0) {
    voicecat::v1::Envelope e;
    e.set_request_id(req_id);
    return e;
}

static voicecat::v1::Permissions all_permissions() {
    voicecat::v1::Permissions p;
    p.set_can_create_temp_channel(true);
    p.set_can_kick(true);
    p.set_can_ban(true);
    p.set_can_move_users(true);
    p.set_can_admin_accounts(true);
    p.set_is_admin(true);
    return p;
}

static voicecat::v1::Permissions no_permissions() {
    voicecat::v1::Permissions p;
    return p;
}

ConnSession::ConnSession(std::shared_ptr<Database>              db,
                         std::shared_ptr<SessionRegistry>       registry,
                         std::shared_ptr<voicecat::WorkerPool>  workers,
                         const std::array<uint8_t, 32>&   server_fp,
                         bool                              allow_guests,
                         uint16_t                          udp_media_port)
    : db_(std::move(db)),
      registry_(std::move(registry)),
      workers_(std::move(workers)),
      server_fp_(server_fp),
      allow_guests_(allow_guests),
      udp_media_port_(udp_media_port) {
    randombytes_buf(udp_token_.data(), udp_token_.size());
}

void ConnSession::set_io(SendFn send_fn, CloseFn close_fn) {
    send_fn_  = std::move(send_fn);
    close_fn_ = std::move(close_fn);
}

void ConnSession::begin() {
    touch_last_seen();
    // Nothing to do at TCP level — wait for ClientHello
}

void ConnSession::on_frame(std::vector<uint8_t> frame) {
    touch_last_seen();  // any inbound TCP activity keeps this session off the reaper's list
    voicecat::v1::Envelope env;
    if (!protocol::decode_envelope(frame, env)) return;

    auto st = state_.load(std::memory_order_acquire);
    switch (env.body_case()) {
        case voicecat::v1::Envelope::kClientHello:
            if (st == State::WaitingHello)
                handle_client_hello(env.request_id(), env.client_hello());
            break;
        case voicecat::v1::Envelope::kAuthRequest:
            if (st == State::WaitingAuth)
                handle_auth_request(env.request_id(), env.auth_request());
            break;
        case voicecat::v1::Envelope::kJoinChannel:
            if (st == State::Authenticated)
                handle_join_channel(env.request_id(), env.join_channel());
            break;
        case voicecat::v1::Envelope::kTextMessage:
            if (st == State::Authenticated)
                handle_text_message(env.text_message());
            break;
        case voicecat::v1::Envelope::kPing:
            handle_ping(env.ping());
            break;
        case voicecat::v1::Envelope::kDisconnect:
            // Client-initiated graceful disconnect (code=0). Falls through to close() which
            // broadcasts UserEvent::LEFT — same as a TCP drop, but immediate (no reaper/EOF
            // wait). Gated on Authenticated so a pre-auth stray Disconnect can't skip cleanup.
            if (st == State::Authenticated) handle_client_disconnect(env.disconnect());
            break;
        case voicecat::v1::Envelope::kLeaveChannel:
            if (st == State::Authenticated)
                handle_leave_channel();
            break;
        case voicecat::v1::Envelope::kUdpBinding:
            if (st == State::Authenticated)
                handle_udp_binding(env.request_id(), env.udp_binding());
            break;
        case voicecat::v1::Envelope::kStreamAnnounce:
            if (st == State::Authenticated)
                handle_stream_announce(env.request_id(), env.stream_announce());
            break;
        case voicecat::v1::Envelope::kStreamStop:
            if (st == State::Authenticated)
                handle_stream_stop(env.stream_stop());
            break;

        // ── M5 moderation / admin ─────────────────────────────────────────────
        case voicecat::v1::Envelope::kKick:
            if (st == State::Authenticated) handle_kick_request(env.request_id(), env.kick());
            break;
        case voicecat::v1::Envelope::kBan:
            if (st == State::Authenticated) handle_ban_request(env.request_id(), env.ban());
            break;
        case voicecat::v1::Envelope::kSetPermission:
            if (st == State::Authenticated)
                handle_set_permission(env.request_id(), env.set_permission());
            break;
        case voicecat::v1::Envelope::kServerMute:
            if (st == State::Authenticated)
                handle_server_mute_request(env.request_id(), env.server_mute());
            break;
        case voicecat::v1::Envelope::kMoveUser:
            if (st == State::Authenticated) handle_move_user(env.request_id(), env.move_user());
            break;
        case voicecat::v1::Envelope::kCreateChannel:
            if (st == State::Authenticated)
                handle_create_channel(env.request_id(), env.create_channel());
            break;
        case voicecat::v1::Envelope::kEditChannel:
            if (st == State::Authenticated)
                handle_edit_channel(env.request_id(), env.edit_channel());
            break;
        case voicecat::v1::Envelope::kDeleteChannel:
            if (st == State::Authenticated)
                handle_delete_channel(env.request_id(), env.delete_channel());
            break;
        case voicecat::v1::Envelope::kCreateAccount:
            if (st == State::Authenticated)
                handle_create_account(env.request_id(), env.create_account());
            break;
        case voicecat::v1::Envelope::kResetPassword:
            if (st == State::Authenticated)
                handle_reset_password(env.request_id(), env.reset_password());
            break;
        case voicecat::v1::Envelope::kDeleteAccount:
            if (st == State::Authenticated)
                handle_delete_account(env.request_id(), env.delete_account());
            break;
        case voicecat::v1::Envelope::kListAccounts:
            if (st == State::Authenticated)
                handle_list_accounts(env.request_id(), env.list_accounts());
            break;

        default:
            break;
    }
}

void ConnSession::on_disconnect() { close(); }

void ConnSession::send_envelope(const voicecat::v1::Envelope& env) {
    if (!send_fn_ || closed_.load()) return;
    // Serialize to raw protobuf bytes; send_fn_ (→ TcpServerConn::send_frame)
    // adds the [4-byte len] framing, so we must NOT pre-frame here.
    std::string bytes;
    if (!env.SerializeToString(&bytes)) return;
    std::vector<uint8_t> raw(bytes.begin(), bytes.end());
    send_fn_(std::move(raw));
}

void ConnSession::close() {
    if (closed_.exchange(true)) return;
    state_.store(State::Disconnecting, std::memory_order_release);
    uint32_t uid = user_id_.load();
    if (uid) {
        // Broadcast LEFT BEFORE erasing the user, so remaining clients (and the audio
        // engine's remove_stream path on each peer) learn about the departure. This
        // covers ungraceful disconnects (TCP drop, crash, network loss) that previously
        // silently erased the user from the registry without notifying anyone — which
        // left stale users in peer client lists and kept Opus PLC hissing forever on
        // peers whose remove_stream was never triggered. Mirrors kick_user's first half
        // (session_registry.cpp kick_user). broadcast_left releases its shared_lock
        // before remove_user acquires the unique_lock, so no deadlock; and send_envelope
        // on this session is a no-op now that closed_ is true.
        registry_->broadcast_left(uid, "");
        registry_->remove_user(uid);
    }
    if (session_id_) registry_->unregister_session(session_id_);
    if (close_fn_) close_fn_();
}

// ── M2: media crypto ─────────────────────────────────────────────────────────

void ConnSession::set_media_crypto(
    std::unique_ptr<voicecat::crypto::SodiumMediaCrypto> send,
    std::unique_ptr<voicecat::crypto::SodiumMediaCrypto> recv) {
    std::lock_guard lk(crypto_mu_);
    send_crypto_ = std::move(send);
    recv_crypto_ = std::move(recv);
}

voicecat::crypto::SodiumMediaCrypto* ConnSession::send_crypto() {
    std::lock_guard lk(crypto_mu_);
    return send_crypto_.get();
}

voicecat::crypto::SodiumMediaCrypto* ConnSession::recv_crypto() {
    std::lock_guard lk(crypto_mu_);
    return recv_crypto_.get();
}

// ── M2: UDP endpoint ─────────────────────────────────────────────────────────

void ConnSession::set_udp_endpoint(asio::ip::udp::endpoint ep) {
    {
        std::lock_guard lk(udp_ep_mu_);
        udp_ep_ = ep;
    }
    has_udp_ep_.store(true, std::memory_order_release);
    registry_->register_udp_endpoint(ep, session_id_);
}

asio::ip::udp::endpoint ConnSession::udp_endpoint() const {
    std::lock_guard lk(udp_ep_mu_);
    return udp_ep_;
}

// ── Permission helpers ───────────────────────────────────────────────────────

bool ConnSession::has_permission(bool (voicecat::v1::Permissions::* getter)() const) const {
    return (permissions_.*getter)();
}

void ConnSession::set_permissions(const voicecat::v1::Permissions& perms) {
    permissions_ = perms;
    registry_->set_session_permissions(session_id_, perms);
}

void ConnSession::send_generic_result(uint64_t req_id, bool ok, uint32_t code,
                                       const std::string& message) {
    auto env = make_env(req_id);
    auto* gr = env.mutable_generic_result();
    gr->set_ok(ok);
    gr->set_code(code);
    gr->set_message(message);
    send_envelope(env);
}

// ── Handlers ─────────────────────────────────────────────────────────────────

void ConnSession::handle_client_hello(uint64_t req_id, const voicecat::v1::ClientHello& msg) {
    if (msg.proto_version() != 2) {  // protocol v2: 64-bit voice seq (docs/voice.md §2)
        send_disconnect_and_close(1, "unsupported protocol version");
        return;
    }
    auto env = make_env(req_id);
    auto* hello = env.mutable_server_hello();
    hello->set_proto_version(2);
    hello->set_server_name("VoiceCat Server");
    hello->set_server_version("0.1.0");
    if (allow_guests_) hello->add_auth_methods("guest");
    hello->add_auth_methods("password");
    hello->set_server_identity_fingerprint(server_fp_.data(), server_fp_.size());
    if (udp_media_port_) hello->set_udp_port(udp_media_port_);
    send_envelope(env);
    state_.store(State::WaitingAuth, std::memory_order_release);
}

void ConnSession::handle_auth_request(uint64_t req_id, const voicecat::v1::AuthRequest& msg) {
    if (msg.has_guest()) {
        finish_guest_auth(msg.guest(), req_id);
    } else if (msg.has_password()) {
        finish_password_auth(msg.password().username(), msg.password().password(), req_id);
    } else {
        auto env = make_env(req_id);
        env.mutable_auth_result()->set_ok(false);
        env.mutable_auth_result()->set_error("unknown auth method");
        send_envelope(env);
    }
}

void ConnSession::finish_guest_auth(const voicecat::v1::GuestAuth& guest, uint64_t req_id) {
    if (!allow_guests_) {
        auto env = make_env(req_id);
        env.mutable_auth_result()->set_ok(false);
        env.mutable_auth_result()->set_error("guest login not permitted");
        send_envelope(env);
        return;
    }

    voicecat::v1::User user;
    user.set_nickname(guest.nickname().empty() ? "Guest" : guest.nickname());
    user.set_is_guest(true);
    user.set_channel_id(1);

    uint32_t uid = registry_->add_user(session_id_, user);
    user.set_id(uid);
    user_id_.store(uid, std::memory_order_relaxed);
    state_.store(State::Authenticated, std::memory_order_release);

    permissions_ = no_permissions();
    registry_->set_session_permissions(session_id_, permissions_);
    registry_->register_udp_token(udp_token_, session_id_);

    {
        auto env = make_env(req_id);
        auto* res = env.mutable_auth_result();
        res->set_ok(true);
        res->set_session_id(session_id_);
        *res->mutable_self() = user;
        *res->mutable_permissions() = permissions_;
        res->set_udp_token(udp_token_.data(), udp_token_.size());
        send_envelope(env);
    }
    broadcast_user_joined(user);
    send_state_snapshot();
}

void ConnSession::finish_password_auth(const std::string& username,
                                        const std::string& password, uint64_t req_id) {
    // Argon2id runs on the worker pool (deliberately slow).
    auto self = shared_from_this();
    workers_->post([self, username, password, req_id] {
        // M5: check username bans before verifying password.
        if (self->db_->ban_check("username", username)) {
            auto env = make_env(req_id);
            env.mutable_auth_result()->set_ok(false);
            env.mutable_auth_result()->set_error("account banned");
            self->send_envelope(env);
            return;
        }

        auto acc = self->db_->authenticate(username, password);
        if (!acc) {
            auto env = make_env(req_id);
            env.mutable_auth_result()->set_ok(false);
            env.mutable_auth_result()->set_error("invalid credentials");
            self->send_envelope(env);
            return;
        }
        voicecat::v1::User user;
        user.set_nickname(acc->username);
        user.set_is_guest(false);
        user.set_channel_id(1);

        uint32_t uid = self->registry_->add_user(self->session_id_, user);
        user.set_id(uid);
        self->user_id_.store(uid, std::memory_order_relaxed);
        self->state_.store(State::Authenticated, std::memory_order_release);

        voicecat::v1::Permissions perms = acc->is_admin ? all_permissions() : no_permissions();
        self->permissions_ = perms;
        self->registry_->set_session_permissions(self->session_id_, perms);
        self->registry_->register_udp_token(self->udp_token_, self->session_id_);

        {
            auto env = make_env(req_id);
            auto* res = env.mutable_auth_result();
            res->set_ok(true);
            res->set_session_id(self->session_id_);
            *res->mutable_self() = user;
            *res->mutable_permissions() = perms;
            res->set_udp_token(self->udp_token_.data(), self->udp_token_.size());
            self->send_envelope(env);
        }
        self->broadcast_user_joined(user);
        self->send_state_snapshot();
    });
}

void ConnSession::send_state_snapshot() {
    auto env = make_env();
    auto* snap = env.mutable_server_state();
    for (auto& ch : registry_->channel_snapshot()) *snap->add_channels() = ch;
    for (auto& u  : registry_->user_snapshot())    *snap->add_users()    = u;
    send_envelope(env);
}

void ConnSession::broadcast_user_joined(const voicecat::v1::User& user) {
    auto bcast = make_env();
    auto* ue = bcast.mutable_user_event();
    ue->set_kind(voicecat::v1::UserEvent::JOINED);
    *ue->mutable_user() = user;
    registry_->broadcast(bcast, session_id_);
}

void ConnSession::handle_join_channel(uint64_t req_id,
                                       const voicecat::v1::JoinChannelRequest& msg) {
    uint32_t uid = user_id_.load();
    auto ch = registry_->get_channel(msg.channel_id());
    if (!ch) {
        auto env = make_env(req_id);
        auto* res = env.mutable_join_channel_result();
        res->set_ok(false);
        res->set_error("channel not found");
        send_envelope(env);
        return;
    }

    if (ch->password_protected()) {
        if (!registry_->check_channel_password(msg.channel_id(), msg.password())) {
            auto env = make_env(req_id);
            auto* res = env.mutable_join_channel_result();
            res->set_ok(false);
            res->set_error("invalid channel password");
            send_envelope(env);
            return;
        }
    }

    if (ch->max_users() > 0) {
        auto members = registry_->find_channel_sessions(msg.channel_id(), session_id_);
        if (members.size() >= ch->max_users()) {
            auto env = make_env(req_id);
            auto* res = env.mutable_join_channel_result();
            res->set_ok(false);
            res->set_error("channel is full");
            send_envelope(env);
            return;
        }
    }

    bool ok = registry_->set_user_channel(uid, msg.channel_id());
    auto env = make_env(req_id);
    auto* res = env.mutable_join_channel_result();
    res->set_ok(ok);
    if (!ok) {
        res->set_error("channel not found");
    } else {
        res->set_channel_id(msg.channel_id());
        *res->mutable_audio() = ch->audio();

        // Broadcast that this user changed channel — to everyone INCLUDING the mover.
        // The JoinChannelResult only acks the request; this UserEvent is the authoritative
        // state change every client (mover included) applies to its local model. Excluding
        // the mover here is what made it read a stale self-channel. See docs/protocol.md §6.
        if (auto updated_user = registry_->user_snapshot_user(uid)) {
            auto bcast = make_env();
            auto* ue = bcast.mutable_user_event();
            ue->set_kind(voicecat::v1::UserEvent::UPDATED);
            *ue->mutable_user() = *updated_user;
            registry_->broadcast(bcast, /*exclude*/ 0);
        }
    }
    send_envelope(env);
}

void ConnSession::handle_leave_channel() {
    uint32_t uid = user_id_.load();
    if (!uid) return;
    if (!registry_->set_user_channel(uid, 1)) return;
    if (auto updated_user = registry_->user_snapshot_user(uid)) {
        auto bcast = make_env();
        auto* ue = bcast.mutable_user_event();
        ue->set_kind(voicecat::v1::UserEvent::UPDATED);
        *ue->mutable_user() = *updated_user;
        registry_->broadcast(bcast, /*exclude*/ 0);  // include the leaver — same as join
    }
}

void ConnSession::handle_text_message(const voicecat::v1::TextMessage& msg) {
    using namespace std::chrono;
    int64_t now_ms = duration_cast<milliseconds>(
        system_clock::now().time_since_epoch()).count();

    voicecat::v1::TextMessage relay = msg;
    relay.set_sender_id(user_id_.load(std::memory_order_relaxed));
    relay.set_sent_at_unix_ms(now_ms);

    voicecat::v1::Envelope fwd;
    *fwd.mutable_text_message() = relay;

    auto targets = registry_->resolve_text_targets(session_id_, msg.scope(), msg.target_id());
    for (auto& t : targets) t->send_envelope(fwd);

    // Ack
    auto env = make_env();
    auto* ack = env.mutable_text_message_ack();
    ack->set_client_msg_id(msg.client_msg_id());
    ack->set_ok(true);
    send_envelope(env);
}

void ConnSession::handle_ping(const voicecat::v1::Ping& msg) {
    auto env = make_env();
    env.mutable_pong()->set_nonce(msg.nonce());
    send_envelope(env);
}

void ConnSession::handle_client_disconnect(const voicecat::v1::Disconnect& /*msg*/) {
    // Graceful client-initiated disconnect (code=0). close() broadcasts UserEvent::LEFT and
    // cleans up the registry — identical to the TCP-drop path, but triggered by the client's
    // explicit goodbye so peers learn about the departure immediately (no reaper timeout,
    // no EOF detection delay). Idempotent: the closed_ guard in close() handles the
    // inevitable follow-up TCP EOF when the client closes its socket.
    close();
}

void ConnSession::handle_udp_binding(uint64_t req_id, const voicecat::v1::UdpBinding& msg) {
    if (msg.ack()) return;  // server→client direction; ignore if echoed back

    const std::string& tok = msg.udp_token();
    if (tok.size() != 16 || std::memcmp(tok.data(), udp_token_.data(), 16) != 0) {
        // Bad token — silently ignore (don't leak timing information)
        return;
    }

    // Ack over TCP; MediaRelay will set the UDP endpoint when the UDP binding packet arrives.
    auto env = make_env(req_id);
    env.mutable_udp_binding()->set_ack(true);
    send_envelope(env);
}

void ConnSession::handle_stream_announce(uint64_t req_id,
                                          const voicecat::v1::StreamAnnounce& msg) {
    uint32_t ssrc = registry_->assign_ssrc(session_id_);
    uint32_t stream_id = next_stream_id_++;

    auto env = make_env(req_id);
    auto* res = env.mutable_stream_announce_result();
    res->set_ok(true);
    res->set_stream_id(stream_id);
    res->set_ssrc(ssrc);

    // Per-channel AudioConfig is authoritative (docs/voice.md §3): the channel's mode/
    // sample_rate/frame_ms/application/fec/dtx/complexity/expected_packet_loss apply to every
    // stream announced into it, regardless of kind. bitrate_bps is clamped (not overridden) to
    // the channel's ceiling so a client may still request less. sample_rate is taken from the
    // channel verbatim (copied via *eff below) — the codec always runs at 48kHz internally, but
    // a sub-48k value caps the encoder's audio bandwidth (narrowband/wideband; see
    // OpusEncoder::init), so it's a channel policy, not a client choice.
    auto* eff = res->mutable_effective_audio();
    auto chan_cfg = registry_->channel_audio_config(registry_->user_channel(user_id_.load()));
    uint32_t requested_bps =
        msg.has_requested_audio() ? msg.requested_audio().bitrate_bps() : 0;
    if (chan_cfg) {
        *eff = *chan_cfg;
        eff->set_bitrate_bps(requested_bps > 0 ? std::min(requested_bps, chan_cfg->bitrate_bps())
                                                : chan_cfg->bitrate_bps());
    } else if (msg.has_requested_audio()) {
        *eff = msg.requested_audio();
    } else {
        eff->set_codec(0);         // OPUS
        eff->set_sample_rate(48000);
        eff->set_bitrate_bps(24000);
        eff->set_frame_ms(20);
        eff->set_fec(true);
    }
    if (eff->sample_rate() == 0)  eff->set_sample_rate(48000);
    if (eff->bitrate_bps() == 0)  eff->set_bitrate_bps(24000);
    if (eff->frame_ms() == 0)     eff->set_frame_ms(20);

    announced_stream_ids_.push_back(stream_id);

    voicecat::v1::StreamInfo info;
    info.set_stream_id(stream_id);
    info.set_ssrc(ssrc);
    info.set_kind(msg.kind());
    *info.mutable_audio() = *eff;
    info.set_label(msg.label());

    send_envelope(env);

    auto updated = registry_->set_user_stream(user_id_.load(), info);
    if (updated) {
        auto bcast = make_env();
        auto* ue = bcast.mutable_user_event();
        ue->set_kind(voicecat::v1::UserEvent::UPDATED);
        *ue->mutable_user() = *updated;
        registry_->broadcast(bcast, /*exclude*/ 0);  // include announcer; result only acks
    }
}

void ConnSession::handle_stream_stop(const voicecat::v1::StreamStop& msg) {
    auto it = std::find(announced_stream_ids_.begin(), announced_stream_ids_.end(),
                        msg.stream_id());
    if (it == announced_stream_ids_.end()) return;  // not ours — ignore (no spoofed stops)
    announced_stream_ids_.erase(it);

    auto updated = registry_->clear_user_stream(user_id_.load(), msg.stream_id());
    if (updated) {
        auto bcast = make_env();
        auto* ue = bcast.mutable_user_event();
        ue->set_kind(voicecat::v1::UserEvent::UPDATED);
        *ue->mutable_user() = *updated;
        registry_->broadcast(bcast, /*exclude*/ 0);  // include the stopper
    }
}

// ── M5 handlers ──────────────────────────────────────────────────────────────

void ConnSession::handle_kick_request(uint64_t req_id, const voicecat::v1::KickRequest& msg) {
    if (!is_admin() && !has_permission(&voicecat::v1::Permissions::can_kick)) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    bool ok = registry_->kick_user(msg.user_id(), msg.reason());
    send_generic_result(req_id, ok, ok ? 0 : 3, ok ? "" : "user not found");
}

void ConnSession::handle_ban_request(uint64_t req_id, const voicecat::v1::BanRequest& msg) {
    if (!is_admin() && !has_permission(&voicecat::v1::Permissions::can_ban)) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }

    // Ban by username for persistence (nickname == username for password users).
    // Also ban by runtime user_id for immediate effect.
    if (auto target = registry_->find_session_by_user_id(msg.user_id())) {
        if (!target->user_id()) {
            send_generic_result(req_id, false, 3, "user not found");
            return;
        }
        if (auto nick = registry_->user_nickname(target->user_id())) {
            std::string err;
            db_->ban_create("username", *nick, msg.reason(),
                            static_cast<int64_t>(msg.expires_unix_ms()), err);
        }
    }

    bool ok = registry_->ban_user(msg.user_id(), msg.reason(),
                                   static_cast<int64_t>(msg.expires_unix_ms()));
    send_generic_result(req_id, ok, ok ? 0 : 3, ok ? "" : "user not found");
}

void ConnSession::handle_set_permission(uint64_t req_id,
                                         const voicecat::v1::SetPermissionRequest& msg) {
    if (!is_admin() && !has_permission(&voicecat::v1::Permissions::can_admin_accounts)) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    auto target = registry_->find_session_by_user_id(msg.user_id());
    if (!target) {
        send_generic_result(req_id, false, 3, "user not online");
        return;
    }
    target->set_permissions(msg.permissions());
    send_generic_result(req_id, true, 0, "");
}

void ConnSession::handle_server_mute_request(uint64_t req_id,
                                              const voicecat::v1::ServerMuteRequest& msg) {
    if (!is_admin() && !has_permission(&voicecat::v1::Permissions::can_kick)) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    bool ok = registry_->set_server_mute(msg.user_id(), msg.muted(), msg.deafened());
    send_generic_result(req_id, ok, ok ? 0 : 3, ok ? "" : "user not found");
}

void ConnSession::handle_move_user(uint64_t req_id, const voicecat::v1::MoveUserRequest& msg) {
    if (!is_admin() && !has_permission(&voicecat::v1::Permissions::can_move_users)) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    bool ok = registry_->move_user(msg.user_id(), msg.channel_id());
    send_generic_result(req_id, ok, ok ? 0 : 3, ok ? "" : "user or channel not found");
}

void ConnSession::handle_create_channel(uint64_t req_id,
                                         const voicecat::v1::CreateChannelRequest& msg) {
    if (!is_admin() && !has_permission(&voicecat::v1::Permissions::can_create_temp_channel)) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    std::string error;
    uint32_t id = registry_->create_channel(msg.channel(), msg.password(), error);
    send_generic_result(req_id, id != 0, id != 0 ? 0 : 3,
                        id != 0 ? "" : (error.empty() ? "create failed" : error));
}

void ConnSession::handle_edit_channel(uint64_t req_id,
                                       const voicecat::v1::EditChannelRequest& msg) {
    if (!is_admin()) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    std::string error;
    bool ok = registry_->update_channel(msg.channel(), msg.password(), error);
    send_generic_result(req_id, ok, ok ? 0 : 3,
                        ok ? "" : (error.empty() ? "update failed" : error));
}

void ConnSession::handle_delete_channel(uint64_t req_id,
                                         const voicecat::v1::DeleteChannelRequest& msg) {
    if (!is_admin()) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    std::string error;
    bool ok = registry_->delete_channel(msg.channel_id(), error);
    send_generic_result(req_id, ok, ok ? 0 : 3,
                        ok ? "" : (error.empty() ? "delete failed" : error));
}

void ConnSession::handle_create_account(uint64_t req_id,
                                         const voicecat::v1::CreateAccountRequest& msg) {
    if (!is_admin() && !has_permission(&voicecat::v1::Permissions::can_admin_accounts)) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    auto self = shared_from_this();
    workers_->post([self, req_id, msg]() mutable {
        std::string error;
        auto acc = self->db_->create_account(msg.username(), msg.password(), false, error);
        self->send_generic_result(req_id, acc.has_value(), acc.has_value() ? 0 : 3,
                                  acc.has_value() ? "" : error);
    });
}

void ConnSession::handle_reset_password(uint64_t req_id,
                                         const voicecat::v1::ResetPasswordRequest& msg) {
    if (!is_admin() && !has_permission(&voicecat::v1::Permissions::can_admin_accounts)) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    auto self = shared_from_this();
    workers_->post([self, req_id, msg]() mutable {
        std::string error;
        bool ok = self->db_->reset_password(msg.username(), msg.new_password(), error);
        self->send_generic_result(req_id, ok, ok ? 0 : 3, ok ? "" : error);
    });
}

void ConnSession::handle_delete_account(uint64_t req_id,
                                         const voicecat::v1::DeleteAccountRequest& msg) {
    if (!is_admin() && !has_permission(&voicecat::v1::Permissions::can_admin_accounts)) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    std::string error;
    bool ok = db_->delete_account(msg.username(), error);
    send_generic_result(req_id, ok, ok ? 0 : 3, ok ? "" : error);
}

void ConnSession::handle_list_accounts(uint64_t req_id,
                                        const voicecat::v1::ListAccountsRequest& /*msg*/) {
    if (!is_admin() && !has_permission(&voicecat::v1::Permissions::can_admin_accounts)) {
        send_generic_result(req_id, false, 6, "permission denied");
        return;
    }
    auto env = make_env(req_id);
    auto* lr = env.mutable_list_accounts_result();
    for (const auto& acc : db_->list_accounts()) {
        auto* e = lr->add_accounts();
        e->set_username(acc.username);
        e->set_is_admin(acc.is_admin);
        e->set_created_at_unix_ms(static_cast<uint64_t>(acc.created_at) * 1000);
        e->set_last_login_unix_ms(static_cast<uint64_t>(acc.last_login) * 1000);
    }
    send_envelope(env);
}

void ConnSession::send_disconnect_and_close(uint32_t code, const std::string& reason) {
    auto env = make_env();
    auto* d = env.mutable_disconnect();
    d->set_code(code);
    d->set_reason(reason);
    send_envelope(env);
    close();
}

}  // namespace voicecat::server

#endif  // VOICECAT_HAS_NET