pragma Singleton

import Quickshell
import QtQuick

// Which window manager is driving this session? Detected once, from the
// environment only.
//
// This deliberately does no IPC of its own. Widgets branch on these flags to
// pick a backend, and reading a flag must never be able to instantiate the
// service singleton for a window manager that isn't running -- an idle backend
// would sit there retrying a socket that will never answer. Anything that
// wants a backend gates on the matching flag first (`Compositor.isAttwm &&
// Attwm.x`), relying on `&&` / `?:` to leave the other branch untouched.
Singleton {
    // Hyprland always exports this signature.
    readonly property bool _hyprSig: !!Quickshell.env("HYPRLAND_INSTANCE_SIGNATURE")

    // Sway and i3 both point clients at their IPC socket.
    readonly property bool _i3Sock: !!Quickshell.env("SWAYSOCK")
        || !!Quickshell.env("I3SOCK")

    // attwm exports no signature of its own: it is a window management client
    // of river rather than a compositor, so there is nothing session-wide to
    // look for. Treat it as the fallback -- an explicit socket override wins
    // outright, otherwise assume attwm once the two that do announce
    // themselves are ruled out. Guessing wrong is cheap: everything attwm
    // renders also gates on `Attwm.connected`, so a session with no window
    // manager we recognise shows nothing rather than a row of dead tags.
    readonly property bool isAttwm: !!Quickshell.env("ATTWM_SOCKET")
        || (!_hyprSig && !_i3Sock)

    readonly property bool isHyprland: !isAttwm && _hyprSig
    readonly property bool isI3: !isAttwm && !isHyprland && _i3Sock
}