rmux-proto 0.1.2

//! v1 wire compatibility ledger.
//!
//! `FrameKind(u16)` is the v1 compatibility ledger entry identifier. It is
//! deliberately decoupled from the Rust source order of [`crate::Request`] and
//! [`crate::Response`]: each ledger entry pins a stable `u16` for a specific
//! DTO type and direction so that future re-orderings of the Rust enums do
//! not silently change wire identity.
//!
//! The current v1 wire format still encodes DTOs through `bincode_v1`. The
//! ledger therefore additionally pins each variant's bincode tag, and a
//! companion test in `tests/wire_v1.rs` enforces that every active ledger
//! entry's `FrameKind` low bits match the bincode tag observed for a sample
//! value of the corresponding variant.
//!
//! Numeric layout:
//! - `0x0000..=0x7FFF` is reserved for client→server frames.
//! - `0x8000..=0xFFFF` is reserved for server→client frames.
//! - The high bit (`0x8000`) therefore acts as a direction tag and the low
//!   15 bits mirror the bincode tag of the matching variant.
//!
//! Removed or future values stay listed with [`FrameStatus::Reserved`] and are
//! never reused. Adding a new variant requires both an enum entry and a
//! ledger entry; removing a variant requires marking the ledger entry
//! `Reserved` rather than deleting it.

use crate::{Request, Response};

/// Stable v1 frame identifier for a specific DTO type and direction.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
pub struct FrameKind(pub u16);

impl FrameKind {
    /// Direction encoded in the high bit of the kind value.
    #[must_use]
    pub const fn direction(self) -> FrameDirection {
        if self.0 & DIRECTION_BIT == 0 {
            FrameDirection::ClientToServer
        } else {
            FrameDirection::ServerToClient
        }
    }

    /// Returns the bincode tag value (low 15 bits) pinned by this ledger entry.
    #[must_use]
    pub const fn bincode_tag(self) -> u32 {
        (self.0 & !DIRECTION_BIT) as u32
    }
}

/// Direction of a v1 ledger frame.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
pub enum FrameDirection {
    /// Frames sent from client to server.
    ClientToServer,
    /// Frames sent from server to client.
    ServerToClient,
}

impl FrameDirection {
    /// Returns the human-readable wire direction abbreviation.
    #[must_use]
    pub const fn abbreviation(self) -> &'static str {
        match self {
            Self::ClientToServer => "c2s",
            Self::ServerToClient => "s2c",
        }
    }
}

/// Lifecycle status for a ledger entry.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub enum FrameStatus {
    /// The entry is in use by the current build.
    Active,
    /// The entry is permanently reserved and must not be reused.
    Reserved,
}

/// Owning feature area for the ledger entry.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub enum FrameFeature {
    /// Session lifecycle (`new-session`, `kill-session`, ...).
    Sessions,
    /// Window lifecycle and layout (`new-window`, `kill-window`, ...).
    Windows,
    /// Pane lifecycle, input, and listing (`split-window`, `send-keys`, ...).
    Panes,
    /// Layout selection (`select-layout`, `next-layout`, ...).
    Layouts,
    /// Buffer storage (`set-buffer`, `paste-buffer`, ...).
    Buffers,
    /// Format expansion (`display-message`, `if-shell`, ...).
    Formats,
    /// Hook lifecycle (`set-hook`, `show-hooks`, ...).
    Hooks,
    /// Server option configuration (`set-option`, `show-options`, ...).
    Options,
    /// Server lifecycle (`kill-server`, `lock-server`, ...).
    Server,
    /// Client lifecycle (`attach-session`, `refresh-client`, ...).
    Clients,
    /// Key bindings (`bind-key`, `list-keys`, ...).
    Keys,
    /// Internal target resolution.
    Targets,
    /// Control-mode upgrade and clock-mode mounts.
    Control,
    /// Version and capability negotiation.
    Protocol,
    /// Daemon-backed SDK waits and cancellation.
    SdkWaits,
    /// Error envelopes.
    Errors,
    /// Reserved for future extensions.
    Reserved,
}

/// Single v1 wire ledger entry.
#[derive(Debug, Clone, Copy)]
pub struct FrameLedgerEntry {
    /// Stable `u16` ledger identifier.
    pub kind: FrameKind,
    /// Direction of the frame.
    pub direction: FrameDirection,
    /// Lifecycle status.
    pub status: FrameStatus,
    /// Rust DTO type name.
    pub dto_type: &'static str,
    /// Owning feature area.
    pub feature: FrameFeature,
    /// Optional fixture file name (no extension) under `tests/wire-fixtures/v1/`.
    pub fixture: Option<&'static str>,
    /// Compatibility note for the entry.
    pub compatibility_note: &'static str,
}

const DIRECTION_BIT: u16 = 0x8000;

const fn c2s(tag: u16) -> FrameKind {
    FrameKind(tag)
}

const fn s2c(tag: u16) -> FrameKind {
    FrameKind(DIRECTION_BIT | tag)
}

const fn entry(
    kind: FrameKind,
    direction: FrameDirection,
    status: FrameStatus,
    dto_type: &'static str,
    feature: FrameFeature,
    fixture: Option<&'static str>,
    compatibility_note: &'static str,
) -> FrameLedgerEntry {
    FrameLedgerEntry {
        kind,
        direction,
        status,
        dto_type,
        feature,
        fixture,
        compatibility_note,
    }
}

const ACTIVE: FrameStatus = FrameStatus::Active;
const RESERVED: FrameStatus = FrameStatus::Reserved;

/// Authoritative v1 ledger.
///
/// Entries are sorted by `(direction, kind)`.
pub const V1_FRAME_LEDGER: &[FrameLedgerEntry] = &[
    // ----- Client → server -----
    entry(
        c2s(0),
        FrameDirection::ClientToServer,
        ACTIVE,
        "NewSessionRequest",
        FrameFeature::Sessions,
        None,
        "v1 baseline; pinned bincode tag 0.",
    ),
    entry(
        c2s(1),
        FrameDirection::ClientToServer,
        ACTIVE,
        "HasSessionRequest",
        FrameFeature::Sessions,
        Some("has_session_request"),
        "v1 baseline; pinned bincode tag 1.",
    ),
    entry(
        c2s(2),
        FrameDirection::ClientToServer,
        ACTIVE,
        "KillSessionRequest",
        FrameFeature::Sessions,
        Some("kill_session_request"),
        "v1 baseline; pinned bincode tag 2.",
    ),
    entry(
        c2s(3),
        FrameDirection::ClientToServer,
        ACTIVE,
        "NewWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 3.",
    ),
    entry(
        c2s(4),
        FrameDirection::ClientToServer,
        ACTIVE,
        "KillWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 4.",
    ),
    entry(
        c2s(5),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SelectWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 5.",
    ),
    entry(
        c2s(6),
        FrameDirection::ClientToServer,
        ACTIVE,
        "RenameWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 6.",
    ),
    entry(
        c2s(7),
        FrameDirection::ClientToServer,
        ACTIVE,
        "NextWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 7.",
    ),
    entry(
        c2s(8),
        FrameDirection::ClientToServer,
        ACTIVE,
        "PreviousWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 8.",
    ),
    entry(
        c2s(9),
        FrameDirection::ClientToServer,
        ACTIVE,
        "LastWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 9.",
    ),
    entry(
        c2s(10),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ListWindowsRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 10.",
    ),
    entry(
        c2s(11),
        FrameDirection::ClientToServer,
        ACTIVE,
        "MoveWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 11.",
    ),
    entry(
        c2s(12),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SwapWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 12.",
    ),
    entry(
        c2s(13),
        FrameDirection::ClientToServer,
        ACTIVE,
        "RotateWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 13.",
    ),
    entry(
        c2s(14),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SplitWindowRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 14.",
    ),
    entry(
        c2s(15),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SwapPaneRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 15.",
    ),
    entry(
        c2s(16),
        FrameDirection::ClientToServer,
        ACTIVE,
        "LastPaneRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 16.",
    ),
    entry(
        c2s(17),
        FrameDirection::ClientToServer,
        ACTIVE,
        "JoinPaneRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 17.",
    ),
    entry(
        c2s(18),
        FrameDirection::ClientToServer,
        ACTIVE,
        "BreakPaneRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 18.",
    ),
    entry(
        c2s(19),
        FrameDirection::ClientToServer,
        ACTIVE,
        "KillPaneRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 19.",
    ),
    entry(
        c2s(20),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SelectLayoutRequest",
        FrameFeature::Layouts,
        None,
        "v1 baseline; pinned bincode tag 20.",
    ),
    entry(
        c2s(21),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ResizePaneRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 21.",
    ),
    entry(
        c2s(22),
        FrameDirection::ClientToServer,
        ACTIVE,
        "DisplayPanesRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 22.",
    ),
    entry(
        c2s(23),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SelectPaneRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 23.",
    ),
    entry(
        c2s(24),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SelectPaneAdjacentRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 24.",
    ),
    entry(
        c2s(25),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SendKeysRequest",
        FrameFeature::Panes,
        Some("send_keys_request"),
        "v1 baseline; pinned bincode tag 25.",
    ),
    entry(
        c2s(26),
        FrameDirection::ClientToServer,
        ACTIVE,
        "AttachSessionRequest",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 26.",
    ),
    entry(
        c2s(27),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SwitchClientRequest",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 27.",
    ),
    entry(
        c2s(28),
        FrameDirection::ClientToServer,
        ACTIVE,
        "DetachClientRequest",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 28.",
    ),
    entry(
        c2s(29),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SetOptionRequest",
        FrameFeature::Options,
        None,
        "v1 baseline; pinned bincode tag 29.",
    ),
    entry(
        c2s(30),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SetEnvironmentRequest",
        FrameFeature::Options,
        None,
        "v1 baseline; pinned bincode tag 30.",
    ),
    entry(
        c2s(31),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SetHookRequest",
        FrameFeature::Hooks,
        None,
        "v1 baseline; pinned bincode tag 31.",
    ),
    entry(
        c2s(32),
        FrameDirection::ClientToServer,
        ACTIVE,
        "NextLayoutRequest",
        FrameFeature::Layouts,
        None,
        "v1 baseline; pinned bincode tag 32.",
    ),
    entry(
        c2s(33),
        FrameDirection::ClientToServer,
        ACTIVE,
        "PreviousLayoutRequest",
        FrameFeature::Layouts,
        None,
        "v1 baseline; pinned bincode tag 33.",
    ),
    entry(
        c2s(34),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ShowOptionsRequest",
        FrameFeature::Options,
        None,
        "v1 baseline; pinned bincode tag 34.",
    ),
    entry(
        c2s(35),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ShowEnvironmentRequest",
        FrameFeature::Options,
        None,
        "v1 baseline; pinned bincode tag 35.",
    ),
    entry(
        c2s(36),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SetBufferRequest",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 36.",
    ),
    entry(
        c2s(37),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ShowBufferRequest",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 37.",
    ),
    entry(
        c2s(38),
        FrameDirection::ClientToServer,
        ACTIVE,
        "PasteBufferRequest",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 38.",
    ),
    entry(
        c2s(39),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ListBuffersRequest",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 39.",
    ),
    entry(
        c2s(40),
        FrameDirection::ClientToServer,
        ACTIVE,
        "DeleteBufferRequest",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 40.",
    ),
    entry(
        c2s(41),
        FrameDirection::ClientToServer,
        ACTIVE,
        "LoadBufferRequest",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 41.",
    ),
    entry(
        c2s(42),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SaveBufferRequest",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 42.",
    ),
    entry(
        c2s(43),
        FrameDirection::ClientToServer,
        ACTIVE,
        "CapturePaneRequest",
        FrameFeature::Panes,
        Some("capture_pane_request"),
        "v1 baseline; pinned bincode tag 43.",
    ),
    entry(
        c2s(44),
        FrameDirection::ClientToServer,
        ACTIVE,
        "DisplayMessageRequest",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 44.",
    ),
    entry(
        c2s(45),
        FrameDirection::ClientToServer,
        ACTIVE,
        "RunShellRequest",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 45.",
    ),
    entry(
        c2s(46),
        FrameDirection::ClientToServer,
        ACTIVE,
        "IfShellRequest",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 46.",
    ),
    entry(
        c2s(47),
        FrameDirection::ClientToServer,
        ACTIVE,
        "WaitForRequest",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 47.",
    ),
    entry(
        c2s(48),
        FrameDirection::ClientToServer,
        ACTIVE,
        "RenameSessionRequest",
        FrameFeature::Sessions,
        None,
        "v1 baseline; pinned bincode tag 48.",
    ),
    entry(
        c2s(49),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ListSessionsRequest",
        FrameFeature::Sessions,
        None,
        "v1 baseline; pinned bincode tag 49.",
    ),
    entry(
        c2s(50),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ListPanesRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 50.",
    ),
    entry(
        c2s(51),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SourceFileRequest",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 51.",
    ),
    entry(
        c2s(52),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SetOptionByNameRequest",
        FrameFeature::Options,
        None,
        "v1 baseline; pinned bincode tag 52.",
    ),
    entry(
        c2s(53),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SetHookMutationRequest",
        FrameFeature::Hooks,
        None,
        "v1 baseline; pinned bincode tag 53.",
    ),
    entry(
        c2s(54),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ShowHooksRequest",
        FrameFeature::Hooks,
        None,
        "v1 baseline; pinned bincode tag 54.",
    ),
    entry(
        c2s(55),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SendKeysExtRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 55.",
    ),
    entry(
        c2s(56),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SwitchClientExtRequest",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 56.",
    ),
    entry(
        c2s(57),
        FrameDirection::ClientToServer,
        ACTIVE,
        "BindKeyRequest",
        FrameFeature::Keys,
        None,
        "v1 baseline; pinned bincode tag 57.",
    ),
    entry(
        c2s(58),
        FrameDirection::ClientToServer,
        ACTIVE,
        "UnbindKeyRequest",
        FrameFeature::Keys,
        None,
        "v1 baseline; pinned bincode tag 58.",
    ),
    entry(
        c2s(59),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ListKeysRequest",
        FrameFeature::Keys,
        None,
        "v1 baseline; pinned bincode tag 59.",
    ),
    entry(
        c2s(60),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SendPrefixRequest",
        FrameFeature::Keys,
        None,
        "v1 baseline; pinned bincode tag 60.",
    ),
    entry(
        c2s(61),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ClearHistoryRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 61.",
    ),
    entry(
        c2s(62),
        FrameDirection::ClientToServer,
        ACTIVE,
        "CopyModeRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 62.",
    ),
    entry(
        c2s(63),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ControlModeRequest",
        FrameFeature::Control,
        Some("control_mode_request"),
        "v1 baseline; pinned bincode tag 63.",
    ),
    entry(
        c2s(64),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ClockModeRequest",
        FrameFeature::Control,
        None,
        "v1 baseline; pinned bincode tag 64.",
    ),
    entry(
        c2s(65),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ShowMessagesRequest",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 65.",
    ),
    entry(
        c2s(66),
        FrameDirection::ClientToServer,
        ACTIVE,
        "NewSessionExtRequest",
        FrameFeature::Sessions,
        None,
        "v1 baseline; pinned bincode tag 66.",
    ),
    entry(
        c2s(67),
        FrameDirection::ClientToServer,
        ACTIVE,
        "AttachSessionExtRequest",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 67.",
    ),
    entry(
        c2s(68),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SwitchClientExt2Request",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 68.",
    ),
    entry(
        c2s(69),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SelectCustomLayoutRequest",
        FrameFeature::Layouts,
        None,
        "v1 baseline; pinned bincode tag 69.",
    ),
    entry(
        c2s(70),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SelectOldLayoutRequest",
        FrameFeature::Layouts,
        None,
        "v1 baseline; pinned bincode tag 70.",
    ),
    entry(
        c2s(71),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SpreadLayoutRequest",
        FrameFeature::Layouts,
        None,
        "v1 baseline; pinned bincode tag 71.",
    ),
    entry(
        c2s(72),
        FrameDirection::ClientToServer,
        ACTIVE,
        "KillServerRequest",
        FrameFeature::Server,
        None,
        "v1 baseline; pinned bincode tag 72.",
    ),
    entry(
        c2s(73),
        FrameDirection::ClientToServer,
        ACTIVE,
        "LockServerRequest",
        FrameFeature::Server,
        None,
        "v1 baseline; pinned bincode tag 73.",
    ),
    entry(
        c2s(74),
        FrameDirection::ClientToServer,
        ACTIVE,
        "LockSessionRequest",
        FrameFeature::Server,
        None,
        "v1 baseline; pinned bincode tag 74.",
    ),
    entry(
        c2s(75),
        FrameDirection::ClientToServer,
        ACTIVE,
        "LockClientRequest",
        FrameFeature::Server,
        None,
        "v1 baseline; pinned bincode tag 75.",
    ),
    entry(
        c2s(76),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ServerAccessRequest",
        FrameFeature::Server,
        None,
        "v1 baseline; pinned bincode tag 76.",
    ),
    entry(
        c2s(77),
        FrameDirection::ClientToServer,
        ACTIVE,
        "RefreshClientRequest",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 77.",
    ),
    entry(
        c2s(78),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ListClientsRequest",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 78.",
    ),
    entry(
        c2s(79),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SuspendClientRequest",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 79.",
    ),
    entry(
        c2s(80),
        FrameDirection::ClientToServer,
        ACTIVE,
        "DetachClientExtRequest",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 80.",
    ),
    entry(
        c2s(81),
        FrameDirection::ClientToServer,
        ACTIVE,
        "AttachSessionExt2Request",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 81.",
    ),
    entry(
        c2s(82),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SwitchClientExt3Request",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 82.",
    ),
    entry(
        c2s(83),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ResizeWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 83.",
    ),
    entry(
        c2s(84),
        FrameDirection::ClientToServer,
        ACTIVE,
        "RespawnWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 84.",
    ),
    entry(
        c2s(85),
        FrameDirection::ClientToServer,
        ACTIVE,
        "MovePaneRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 85.",
    ),
    entry(
        c2s(86),
        FrameDirection::ClientToServer,
        ACTIVE,
        "PipePaneRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 86.",
    ),
    entry(
        c2s(87),
        FrameDirection::ClientToServer,
        ACTIVE,
        "RespawnPaneRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 87.",
    ),
    entry(
        c2s(88),
        FrameDirection::ClientToServer,
        ACTIVE,
        "LinkWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 88.",
    ),
    entry(
        c2s(89),
        FrameDirection::ClientToServer,
        ACTIVE,
        "UnlinkWindowRequest",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 89.",
    ),
    entry(
        c2s(90),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SelectPaneMarkRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 90.",
    ),
    entry(
        c2s(91),
        FrameDirection::ClientToServer,
        ACTIVE,
        "ResolveTargetRequest",
        FrameFeature::Targets,
        None,
        "v1 baseline; pinned bincode tag 91.",
    ),
    entry(
        c2s(92),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SplitWindowExtRequest",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 92.",
    ),
    entry(
        c2s(93),
        FrameDirection::ClientToServer,
        ACTIVE,
        "HandshakeRequest",
        FrameFeature::Protocol,
        None,
        "v1 capability negotiation; pinned bincode tag 93.",
    ),
    entry(
        c2s(94),
        FrameDirection::ClientToServer,
        ACTIVE,
        "PaneSnapshotRequest",
        FrameFeature::Panes,
        None,
        "Daemon-backed structured pane snapshot endpoint; pinned bincode tag 94.",
    ),
    entry(
        c2s(95),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SubscribePaneOutputRequest",
        FrameFeature::Panes,
        None,
        "Milestone 26 pane output subscription endpoint; pinned bincode tag 95.",
    ),
    entry(
        c2s(96),
        FrameDirection::ClientToServer,
        ACTIVE,
        "UnsubscribePaneOutputRequest",
        FrameFeature::Panes,
        None,
        "Milestone 26 pane output unsubscription endpoint; pinned bincode tag 96.",
    ),
    entry(
        c2s(97),
        FrameDirection::ClientToServer,
        ACTIVE,
        "PaneOutputCursorRequest",
        FrameFeature::Panes,
        None,
        "Milestone 26 pane output cursor endpoint; pinned bincode tag 97.",
    ),
    entry(
        c2s(98),
        FrameDirection::ClientToServer,
        ACTIVE,
        "SdkWaitForOutputRequest",
        FrameFeature::SdkWaits,
        None,
        "Milestone 29 daemon-backed SDK byte wait endpoint; pinned bincode tag 98.",
    ),
    entry(
        c2s(99),
        FrameDirection::ClientToServer,
        ACTIVE,
        "CancelSdkWaitRequest",
        FrameFeature::SdkWaits,
        None,
        "Milestone 29 daemon-backed SDK wait cancellation endpoint; pinned bincode tag 99.",
    ),
    // Reserved client→server slot. Removed values must be listed and never reused.
    entry(
        c2s(0x7FFE),
        FrameDirection::ClientToServer,
        RESERVED,
        "(reserved-c2s-near-end)",
        FrameFeature::Reserved,
        None,
        "Reserved sentinel near the c2s ceiling. Permanently unavailable.",
    ),
    entry(
        c2s(0x7FFF),
        FrameDirection::ClientToServer,
        RESERVED,
        "(reserved-c2s-ceiling)",
        FrameFeature::Reserved,
        None,
        "Last c2s slot. Permanently reserved.",
    ),
    // ----- Server → client -----
    entry(
        s2c(0),
        FrameDirection::ServerToClient,
        ACTIVE,
        "NewSessionResponse",
        FrameFeature::Sessions,
        Some("new_session_response"),
        "v1 baseline; pinned bincode tag 0.",
    ),
    entry(
        s2c(1),
        FrameDirection::ServerToClient,
        ACTIVE,
        "HasSessionResponse",
        FrameFeature::Sessions,
        None,
        "v1 baseline; pinned bincode tag 1.",
    ),
    entry(
        s2c(2),
        FrameDirection::ServerToClient,
        ACTIVE,
        "KillSessionResponse",
        FrameFeature::Sessions,
        None,
        "v1 baseline; pinned bincode tag 2.",
    ),
    entry(
        s2c(3),
        FrameDirection::ServerToClient,
        ACTIVE,
        "NewWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 3.",
    ),
    entry(
        s2c(4),
        FrameDirection::ServerToClient,
        ACTIVE,
        "KillWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 4.",
    ),
    entry(
        s2c(5),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SelectWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 5.",
    ),
    entry(
        s2c(6),
        FrameDirection::ServerToClient,
        ACTIVE,
        "RenameWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 6.",
    ),
    entry(
        s2c(7),
        FrameDirection::ServerToClient,
        ACTIVE,
        "NextWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 7.",
    ),
    entry(
        s2c(8),
        FrameDirection::ServerToClient,
        ACTIVE,
        "PreviousWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 8.",
    ),
    entry(
        s2c(9),
        FrameDirection::ServerToClient,
        ACTIVE,
        "LastWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 9.",
    ),
    entry(
        s2c(10),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ListWindowsResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 10.",
    ),
    entry(
        s2c(11),
        FrameDirection::ServerToClient,
        ACTIVE,
        "MoveWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 11.",
    ),
    entry(
        s2c(12),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SwapWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 12.",
    ),
    entry(
        s2c(13),
        FrameDirection::ServerToClient,
        ACTIVE,
        "RotateWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 13.",
    ),
    entry(
        s2c(14),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SplitWindowResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 14.",
    ),
    entry(
        s2c(15),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SwapPaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 15.",
    ),
    entry(
        s2c(16),
        FrameDirection::ServerToClient,
        ACTIVE,
        "LastPaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 16.",
    ),
    entry(
        s2c(17),
        FrameDirection::ServerToClient,
        ACTIVE,
        "JoinPaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 17.",
    ),
    entry(
        s2c(18),
        FrameDirection::ServerToClient,
        ACTIVE,
        "BreakPaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 18.",
    ),
    entry(
        s2c(19),
        FrameDirection::ServerToClient,
        ACTIVE,
        "KillPaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 19.",
    ),
    entry(
        s2c(20),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SelectLayoutResponse",
        FrameFeature::Layouts,
        None,
        "v1 baseline; pinned bincode tag 20.",
    ),
    entry(
        s2c(21),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ResizePaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 21.",
    ),
    entry(
        s2c(22),
        FrameDirection::ServerToClient,
        ACTIVE,
        "DisplayPanesResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 22.",
    ),
    entry(
        s2c(23),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SelectPaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 23.",
    ),
    entry(
        s2c(24),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SendKeysResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 24.",
    ),
    entry(
        s2c(25),
        FrameDirection::ServerToClient,
        ACTIVE,
        "AttachSessionResponse",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 25.",
    ),
    entry(
        s2c(26),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SwitchClientResponse",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 26.",
    ),
    entry(
        s2c(27),
        FrameDirection::ServerToClient,
        ACTIVE,
        "DetachClientResponse",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 27.",
    ),
    entry(
        s2c(28),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SetOptionResponse",
        FrameFeature::Options,
        None,
        "v1 baseline; pinned bincode tag 28.",
    ),
    entry(
        s2c(29),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SetEnvironmentResponse",
        FrameFeature::Options,
        None,
        "v1 baseline; pinned bincode tag 29.",
    ),
    entry(
        s2c(30),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SetHookResponse",
        FrameFeature::Hooks,
        None,
        "v1 baseline; pinned bincode tag 30.",
    ),
    entry(
        s2c(31),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ErrorResponse",
        FrameFeature::Errors,
        Some("error_response"),
        "v1 baseline; pinned bincode tag 31.",
    ),
    entry(
        s2c(32),
        FrameDirection::ServerToClient,
        ACTIVE,
        "NextLayoutResponse",
        FrameFeature::Layouts,
        None,
        "v1 baseline; pinned bincode tag 32.",
    ),
    entry(
        s2c(33),
        FrameDirection::ServerToClient,
        ACTIVE,
        "PreviousLayoutResponse",
        FrameFeature::Layouts,
        None,
        "v1 baseline; pinned bincode tag 33.",
    ),
    entry(
        s2c(34),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ShowOptionsResponse",
        FrameFeature::Options,
        None,
        "v1 baseline; pinned bincode tag 34.",
    ),
    entry(
        s2c(35),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ShowEnvironmentResponse",
        FrameFeature::Options,
        None,
        "v1 baseline; pinned bincode tag 35.",
    ),
    entry(
        s2c(36),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SetBufferResponse",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 36.",
    ),
    entry(
        s2c(37),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ShowBufferResponse",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 37.",
    ),
    entry(
        s2c(38),
        FrameDirection::ServerToClient,
        ACTIVE,
        "PasteBufferResponse",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 38.",
    ),
    entry(
        s2c(39),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ListBuffersResponse",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 39.",
    ),
    entry(
        s2c(40),
        FrameDirection::ServerToClient,
        ACTIVE,
        "DeleteBufferResponse",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 40.",
    ),
    entry(
        s2c(41),
        FrameDirection::ServerToClient,
        ACTIVE,
        "LoadBufferResponse",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 41.",
    ),
    entry(
        s2c(42),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SaveBufferResponse",
        FrameFeature::Buffers,
        None,
        "v1 baseline; pinned bincode tag 42.",
    ),
    entry(
        s2c(43),
        FrameDirection::ServerToClient,
        ACTIVE,
        "CapturePaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 43.",
    ),
    entry(
        s2c(44),
        FrameDirection::ServerToClient,
        ACTIVE,
        "DisplayMessageResponse",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 44.",
    ),
    entry(
        s2c(45),
        FrameDirection::ServerToClient,
        ACTIVE,
        "RunShellResponse",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 45.",
    ),
    entry(
        s2c(46),
        FrameDirection::ServerToClient,
        ACTIVE,
        "IfShellResponse",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 46.",
    ),
    entry(
        s2c(47),
        FrameDirection::ServerToClient,
        ACTIVE,
        "WaitForResponse",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 47.",
    ),
    entry(
        s2c(48),
        FrameDirection::ServerToClient,
        ACTIVE,
        "RenameSessionResponse",
        FrameFeature::Sessions,
        None,
        "v1 baseline; pinned bincode tag 48.",
    ),
    entry(
        s2c(49),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ListSessionsResponse",
        FrameFeature::Sessions,
        None,
        "v1 baseline; pinned bincode tag 49.",
    ),
    entry(
        s2c(50),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ListPanesResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 50.",
    ),
    entry(
        s2c(51),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SourceFileResponse",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 51.",
    ),
    entry(
        s2c(52),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SetOptionByNameResponse",
        FrameFeature::Options,
        None,
        "v1 baseline; pinned bincode tag 52.",
    ),
    entry(
        s2c(53),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ShowHooksResponse",
        FrameFeature::Hooks,
        None,
        "v1 baseline; pinned bincode tag 53.",
    ),
    entry(
        s2c(54),
        FrameDirection::ServerToClient,
        ACTIVE,
        "BindKeyResponse",
        FrameFeature::Keys,
        None,
        "v1 baseline; pinned bincode tag 54.",
    ),
    entry(
        s2c(55),
        FrameDirection::ServerToClient,
        ACTIVE,
        "UnbindKeyResponse",
        FrameFeature::Keys,
        None,
        "v1 baseline; pinned bincode tag 55.",
    ),
    entry(
        s2c(56),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ListKeysResponse",
        FrameFeature::Keys,
        None,
        "v1 baseline; pinned bincode tag 56.",
    ),
    entry(
        s2c(57),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SendPrefixResponse",
        FrameFeature::Keys,
        None,
        "v1 baseline; pinned bincode tag 57.",
    ),
    entry(
        s2c(58),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ClearHistoryResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 58.",
    ),
    entry(
        s2c(59),
        FrameDirection::ServerToClient,
        ACTIVE,
        "CopyModeResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 59.",
    ),
    entry(
        s2c(60),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ControlModeResponse",
        FrameFeature::Control,
        None,
        "v1 baseline; pinned bincode tag 60.",
    ),
    entry(
        s2c(61),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ClockModeResponse",
        FrameFeature::Control,
        None,
        "v1 baseline; pinned bincode tag 61.",
    ),
    entry(
        s2c(62),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ShowMessagesResponse",
        FrameFeature::Formats,
        None,
        "v1 baseline; pinned bincode tag 62.",
    ),
    entry(
        s2c(63),
        FrameDirection::ServerToClient,
        ACTIVE,
        "KillServerResponse",
        FrameFeature::Server,
        None,
        "v1 baseline; pinned bincode tag 63.",
    ),
    entry(
        s2c(64),
        FrameDirection::ServerToClient,
        ACTIVE,
        "LockServerResponse",
        FrameFeature::Server,
        None,
        "v1 baseline; pinned bincode tag 64.",
    ),
    entry(
        s2c(65),
        FrameDirection::ServerToClient,
        ACTIVE,
        "LockSessionResponse",
        FrameFeature::Server,
        None,
        "v1 baseline; pinned bincode tag 65.",
    ),
    entry(
        s2c(66),
        FrameDirection::ServerToClient,
        ACTIVE,
        "LockClientResponse",
        FrameFeature::Server,
        None,
        "v1 baseline; pinned bincode tag 66.",
    ),
    entry(
        s2c(67),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ServerAccessResponse",
        FrameFeature::Server,
        None,
        "v1 baseline; pinned bincode tag 67.",
    ),
    entry(
        s2c(68),
        FrameDirection::ServerToClient,
        ACTIVE,
        "RefreshClientResponse",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 68.",
    ),
    entry(
        s2c(69),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ListClientsResponse",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 69.",
    ),
    entry(
        s2c(70),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SuspendClientResponse",
        FrameFeature::Clients,
        None,
        "v1 baseline; pinned bincode tag 70.",
    ),
    entry(
        s2c(71),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ResizeWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 71.",
    ),
    entry(
        s2c(72),
        FrameDirection::ServerToClient,
        ACTIVE,
        "RespawnWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 72.",
    ),
    entry(
        s2c(73),
        FrameDirection::ServerToClient,
        ACTIVE,
        "MovePaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 73.",
    ),
    entry(
        s2c(74),
        FrameDirection::ServerToClient,
        ACTIVE,
        "PipePaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 74.",
    ),
    entry(
        s2c(75),
        FrameDirection::ServerToClient,
        ACTIVE,
        "RespawnPaneResponse",
        FrameFeature::Panes,
        None,
        "v1 baseline; pinned bincode tag 75.",
    ),
    entry(
        s2c(76),
        FrameDirection::ServerToClient,
        ACTIVE,
        "LinkWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 76.",
    ),
    entry(
        s2c(77),
        FrameDirection::ServerToClient,
        ACTIVE,
        "UnlinkWindowResponse",
        FrameFeature::Windows,
        None,
        "v1 baseline; pinned bincode tag 77.",
    ),
    entry(
        s2c(78),
        FrameDirection::ServerToClient,
        ACTIVE,
        "ResolveTargetResponse",
        FrameFeature::Targets,
        None,
        "v1 baseline; pinned bincode tag 78.",
    ),
    entry(
        s2c(79),
        FrameDirection::ServerToClient,
        ACTIVE,
        "HandshakeResponse",
        FrameFeature::Protocol,
        None,
        "v1 capability negotiation; pinned bincode tag 79.",
    ),
    entry(
        s2c(80),
        FrameDirection::ServerToClient,
        ACTIVE,
        "PaneSnapshotResponse",
        FrameFeature::Panes,
        None,
        "Daemon-backed structured pane snapshot endpoint; pinned bincode tag 80.",
    ),
    entry(
        s2c(81),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SubscribePaneOutputResponse",
        FrameFeature::Panes,
        None,
        "Milestone 26 pane output subscription response; pinned bincode tag 81.",
    ),
    entry(
        s2c(82),
        FrameDirection::ServerToClient,
        ACTIVE,
        "UnsubscribePaneOutputResponse",
        FrameFeature::Panes,
        None,
        "Milestone 26 pane output unsubscription response; pinned bincode tag 82.",
    ),
    entry(
        s2c(83),
        FrameDirection::ServerToClient,
        ACTIVE,
        "PaneOutputCursorResponse",
        FrameFeature::Panes,
        None,
        "Milestone 26 pane output cursor response; pinned bincode tag 83.",
    ),
    entry(
        s2c(84),
        FrameDirection::ServerToClient,
        ACTIVE,
        "PaneOutputLagResponse",
        FrameFeature::Panes,
        None,
        "Milestone 26 pane output lag notice response; pinned bincode tag 84.",
    ),
    entry(
        s2c(85),
        FrameDirection::ServerToClient,
        ACTIVE,
        "SdkWaitForOutputResponse",
        FrameFeature::SdkWaits,
        None,
        "Milestone 29 daemon-backed SDK byte wait response; pinned bincode tag 85.",
    ),
    entry(
        s2c(86),
        FrameDirection::ServerToClient,
        ACTIVE,
        "CancelSdkWaitResponse",
        FrameFeature::SdkWaits,
        None,
        "Milestone 29 daemon-backed SDK wait cancellation response; pinned bincode tag 86.",
    ),
    // Reserved server→client slot. Removed values must be listed and never reused.
    entry(
        s2c(0x7FFE),
        FrameDirection::ServerToClient,
        RESERVED,
        "(reserved-s2c-near-end)",
        FrameFeature::Reserved,
        None,
        "Reserved sentinel near the s2c ceiling. Permanently unavailable.",
    ),
    entry(
        s2c(0x7FFF),
        FrameDirection::ServerToClient,
        RESERVED,
        "(reserved-s2c-ceiling)",
        FrameFeature::Reserved,
        None,
        "Last s2c slot. Permanently reserved.",
    ),
];

/// Returns the recorded `FrameKind` for a `Request` value.
///
/// The match is exhaustive on the v1 `Request` variants. Reordering or
/// renaming variants requires updating both this match and the corresponding
/// ledger entry.
#[must_use]
pub const fn frame_kind_for_request(request: &Request) -> FrameKind {
    match request {
        Request::NewSession(_) => c2s(0),
        Request::HasSession(_) => c2s(1),
        Request::KillSession(_) => c2s(2),
        Request::NewWindow(_) => c2s(3),
        Request::KillWindow(_) => c2s(4),
        Request::SelectWindow(_) => c2s(5),
        Request::RenameWindow(_) => c2s(6),
        Request::NextWindow(_) => c2s(7),
        Request::PreviousWindow(_) => c2s(8),
        Request::LastWindow(_) => c2s(9),
        Request::ListWindows(_) => c2s(10),
        Request::MoveWindow(_) => c2s(11),
        Request::SwapWindow(_) => c2s(12),
        Request::RotateWindow(_) => c2s(13),
        Request::SplitWindow(_) => c2s(14),
        Request::SwapPane(_) => c2s(15),
        Request::LastPane(_) => c2s(16),
        Request::JoinPane(_) => c2s(17),
        Request::BreakPane(_) => c2s(18),
        Request::KillPane(_) => c2s(19),
        Request::SelectLayout(_) => c2s(20),
        Request::ResizePane(_) => c2s(21),
        Request::DisplayPanes(_) => c2s(22),
        Request::SelectPane(_) => c2s(23),
        Request::SelectPaneAdjacent(_) => c2s(24),
        Request::SendKeys(_) => c2s(25),
        Request::AttachSession(_) => c2s(26),
        Request::SwitchClient(_) => c2s(27),
        Request::DetachClient(_) => c2s(28),
        Request::SetOption(_) => c2s(29),
        Request::SetEnvironment(_) => c2s(30),
        Request::SetHook(_) => c2s(31),
        Request::NextLayout(_) => c2s(32),
        Request::PreviousLayout(_) => c2s(33),
        Request::ShowOptions(_) => c2s(34),
        Request::ShowEnvironment(_) => c2s(35),
        Request::SetBuffer(_) => c2s(36),
        Request::ShowBuffer(_) => c2s(37),
        Request::PasteBuffer(_) => c2s(38),
        Request::ListBuffers(_) => c2s(39),
        Request::DeleteBuffer(_) => c2s(40),
        Request::LoadBuffer(_) => c2s(41),
        Request::SaveBuffer(_) => c2s(42),
        Request::CapturePane(_) => c2s(43),
        Request::DisplayMessage(_) => c2s(44),
        Request::RunShell(_) => c2s(45),
        Request::IfShell(_) => c2s(46),
        Request::WaitFor(_) => c2s(47),
        Request::RenameSession(_) => c2s(48),
        Request::ListSessions(_) => c2s(49),
        Request::ListPanes(_) => c2s(50),
        Request::SourceFile(_) => c2s(51),
        Request::SetOptionByName(_) => c2s(52),
        Request::SetHookMutation(_) => c2s(53),
        Request::ShowHooks(_) => c2s(54),
        Request::SendKeysExt(_) => c2s(55),
        Request::SwitchClientExt(_) => c2s(56),
        Request::BindKey(_) => c2s(57),
        Request::UnbindKey(_) => c2s(58),
        Request::ListKeys(_) => c2s(59),
        Request::SendPrefix(_) => c2s(60),
        Request::ClearHistory(_) => c2s(61),
        Request::CopyMode(_) => c2s(62),
        Request::ControlMode(_) => c2s(63),
        Request::ClockMode(_) => c2s(64),
        Request::ShowMessages(_) => c2s(65),
        Request::NewSessionExt(_) => c2s(66),
        Request::AttachSessionExt(_) => c2s(67),
        Request::SwitchClientExt2(_) => c2s(68),
        Request::SelectCustomLayout(_) => c2s(69),
        Request::SelectOldLayout(_) => c2s(70),
        Request::SpreadLayout(_) => c2s(71),
        Request::KillServer(_) => c2s(72),
        Request::LockServer(_) => c2s(73),
        Request::LockSession(_) => c2s(74),
        Request::LockClient(_) => c2s(75),
        Request::ServerAccess(_) => c2s(76),
        Request::RefreshClient(_) => c2s(77),
        Request::ListClients(_) => c2s(78),
        Request::SuspendClient(_) => c2s(79),
        Request::DetachClientExt(_) => c2s(80),
        Request::AttachSessionExt2(_) => c2s(81),
        Request::SwitchClientExt3(_) => c2s(82),
        Request::ResizeWindow(_) => c2s(83),
        Request::RespawnWindow(_) => c2s(84),
        Request::MovePane(_) => c2s(85),
        Request::PipePane(_) => c2s(86),
        Request::RespawnPane(_) => c2s(87),
        Request::LinkWindow(_) => c2s(88),
        Request::UnlinkWindow(_) => c2s(89),
        Request::SelectPaneMark(_) => c2s(90),
        Request::ResolveTarget(_) => c2s(91),
        Request::SplitWindowExt(_) => c2s(92),
        Request::Handshake(_) => c2s(93),
        Request::PaneSnapshot(_) => c2s(94),
        Request::SubscribePaneOutput(_) => c2s(95),
        Request::UnsubscribePaneOutput(_) => c2s(96),
        Request::PaneOutputCursor(_) => c2s(97),
        Request::SdkWaitForOutput(_) => c2s(98),
        Request::CancelSdkWait(_) => c2s(99),
    }
}

/// Returns the recorded `FrameKind` for a `Response` value.
#[must_use]
pub const fn frame_kind_for_response(response: &Response) -> FrameKind {
    match response {
        Response::NewSession(_) => s2c(0),
        Response::HasSession(_) => s2c(1),
        Response::KillSession(_) => s2c(2),
        Response::NewWindow(_) => s2c(3),
        Response::KillWindow(_) => s2c(4),
        Response::SelectWindow(_) => s2c(5),
        Response::RenameWindow(_) => s2c(6),
        Response::NextWindow(_) => s2c(7),
        Response::PreviousWindow(_) => s2c(8),
        Response::LastWindow(_) => s2c(9),
        Response::ListWindows(_) => s2c(10),
        Response::MoveWindow(_) => s2c(11),
        Response::SwapWindow(_) => s2c(12),
        Response::RotateWindow(_) => s2c(13),
        Response::SplitWindow(_) => s2c(14),
        Response::SwapPane(_) => s2c(15),
        Response::LastPane(_) => s2c(16),
        Response::JoinPane(_) => s2c(17),
        Response::BreakPane(_) => s2c(18),
        Response::KillPane(_) => s2c(19),
        Response::SelectLayout(_) => s2c(20),
        Response::ResizePane(_) => s2c(21),
        Response::DisplayPanes(_) => s2c(22),
        Response::SelectPane(_) => s2c(23),
        Response::SendKeys(_) => s2c(24),
        Response::AttachSession(_) => s2c(25),
        Response::SwitchClient(_) => s2c(26),
        Response::DetachClient(_) => s2c(27),
        Response::SetOption(_) => s2c(28),
        Response::SetEnvironment(_) => s2c(29),
        Response::SetHook(_) => s2c(30),
        Response::Error(_) => s2c(31),
        Response::NextLayout(_) => s2c(32),
        Response::PreviousLayout(_) => s2c(33),
        Response::ShowOptions(_) => s2c(34),
        Response::ShowEnvironment(_) => s2c(35),
        Response::SetBuffer(_) => s2c(36),
        Response::ShowBuffer(_) => s2c(37),
        Response::PasteBuffer(_) => s2c(38),
        Response::ListBuffers(_) => s2c(39),
        Response::DeleteBuffer(_) => s2c(40),
        Response::LoadBuffer(_) => s2c(41),
        Response::SaveBuffer(_) => s2c(42),
        Response::CapturePane(_) => s2c(43),
        Response::DisplayMessage(_) => s2c(44),
        Response::RunShell(_) => s2c(45),
        Response::IfShell(_) => s2c(46),
        Response::WaitFor(_) => s2c(47),
        Response::RenameSession(_) => s2c(48),
        Response::ListSessions(_) => s2c(49),
        Response::ListPanes(_) => s2c(50),
        Response::SourceFile(_) => s2c(51),
        Response::SetOptionByName(_) => s2c(52),
        Response::ShowHooks(_) => s2c(53),
        Response::BindKey(_) => s2c(54),
        Response::UnbindKey(_) => s2c(55),
        Response::ListKeys(_) => s2c(56),
        Response::SendPrefix(_) => s2c(57),
        Response::ClearHistory(_) => s2c(58),
        Response::CopyMode(_) => s2c(59),
        Response::ControlMode(_) => s2c(60),
        Response::ClockMode(_) => s2c(61),
        Response::ShowMessages(_) => s2c(62),
        Response::KillServer(_) => s2c(63),
        Response::LockServer(_) => s2c(64),
        Response::LockSession(_) => s2c(65),
        Response::LockClient(_) => s2c(66),
        Response::ServerAccess(_) => s2c(67),
        Response::RefreshClient(_) => s2c(68),
        Response::ListClients(_) => s2c(69),
        Response::SuspendClient(_) => s2c(70),
        Response::ResizeWindow(_) => s2c(71),
        Response::RespawnWindow(_) => s2c(72),
        Response::MovePane(_) => s2c(73),
        Response::PipePane(_) => s2c(74),
        Response::RespawnPane(_) => s2c(75),
        Response::LinkWindow(_) => s2c(76),
        Response::UnlinkWindow(_) => s2c(77),
        Response::ResolveTarget(_) => s2c(78),
        Response::Handshake(_) => s2c(79),
        Response::PaneSnapshot(_) => s2c(80),
        Response::SubscribePaneOutput(_) => s2c(81),
        Response::UnsubscribePaneOutput(_) => s2c(82),
        Response::PaneOutputCursor(_) => s2c(83),
        Response::PaneOutputLag(_) => s2c(84),
        Response::SdkWaitForOutput(_) => s2c(85),
        Response::CancelSdkWait(_) => s2c(86),
    }
}

/// Looks up a ledger entry by its `FrameKind` value.
#[must_use]
pub fn ledger_entry_for(kind: FrameKind) -> Option<&'static FrameLedgerEntry> {
    V1_FRAME_LEDGER.iter().find(|entry| entry.kind == kind)
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn ledger_kinds_are_unique() {
        let mut seen = std::collections::HashSet::new();
        for entry in V1_FRAME_LEDGER {
            assert!(
                seen.insert(entry.kind),
                "duplicate FrameKind {:#06x} for {}",
                entry.kind.0,
                entry.dto_type
            );
        }
    }

    #[test]
    fn direction_bit_partitions_kinds() {
        for entry in V1_FRAME_LEDGER {
            assert_eq!(entry.kind.direction(), entry.direction);
        }
    }

    #[test]
    fn fixture_names_are_unique() {
        let mut seen = std::collections::HashSet::new();
        for entry in V1_FRAME_LEDGER {
            if let Some(name) = entry.fixture {
                assert!(seen.insert(name), "duplicate fixture {name}");
            }
        }
    }

    #[test]
    fn reserved_entries_have_reserved_feature() {
        for entry in V1_FRAME_LEDGER {
            if matches!(entry.status, FrameStatus::Reserved) {
                assert!(matches!(entry.feature, FrameFeature::Reserved));
            }
        }
    }

    #[test]
    fn bincode_tag_never_uses_direction_bit() {
        // Edge case: any entry whose `bincode_tag()` is >= 0x8000 means a
        // direction bit leaked into the payload tag, which would corrupt
        // the bincode wire encoding for that variant.
        for entry in V1_FRAME_LEDGER {
            assert!(
                entry.kind.bincode_tag() < 0x8000,
                "ledger entry {} kind {:#06x} bincode_tag {} ≥ 0x8000",
                entry.dto_type,
                entry.kind.0,
                entry.kind.bincode_tag(),
            );
        }
    }

    #[test]
    fn ledger_entry_for_returns_each_active_entry() {
        // Edge case: every entry recorded in the ledger must be reachable
        // through the public `ledger_entry_for` lookup. Catches a future
        // change that splits the ledger into multiple slices but forgets
        // to register one of them.
        for entry in V1_FRAME_LEDGER {
            let looked_up = ledger_entry_for(entry.kind)
                .unwrap_or_else(|| panic!("kind {:#06x} not reachable", entry.kind.0));
            assert_eq!(looked_up.kind, entry.kind);
            assert_eq!(looked_up.direction, entry.direction);
            assert_eq!(looked_up.dto_type, entry.dto_type);
        }
    }

    #[test]
    fn reserved_kinds_keep_direction_bit_consistent() {
        // Reserved sentinels live near the ceiling of each direction band.
        // Their stored `kind` value's high bit must agree with their
        // recorded `direction`; otherwise a contributor could "reserve" a
        // c2s slot inside the s2c band by mistake.
        for entry in V1_FRAME_LEDGER
            .iter()
            .filter(|entry| matches!(entry.status, FrameStatus::Reserved))
        {
            let direction_bit_set = entry.kind.0 & DIRECTION_BIT != 0;
            match entry.direction {
                FrameDirection::ClientToServer => assert!(
                    !direction_bit_set,
                    "reserved c2s entry {:#06x} has direction bit set",
                    entry.kind.0
                ),
                FrameDirection::ServerToClient => assert!(
                    direction_bit_set,
                    "reserved s2c entry {:#06x} missing direction bit",
                    entry.kind.0
                ),
            }
        }
    }
}