nixos/settings/quickshell/Greeter.qml

import Quickshell
import Quickshell.Services.Greetd
import QtQuick
import QtQuick.Window

Window {
    id: root
    visible: true
    visibility: Window.FullScreen
    flags: Qt.Window | Qt.FramelessWindowHint
    onClosing: close => { close.accepted = false; }
    color: "black"
    property string password: ""
    property string errorMessage: ""
    property bool busy: false
    Component.onCompleted: Quickshell.watchFiles = false

    function failed(message) {
        password = "";
        busy = false;
        errorMessage = message;
        handoff.stop();
        veil.opacity = 0;
    }
    Connections {
        target: Greetd
        function onAuthMessage(message, error, responseRequired, echoResponse) {
            if (responseRequired) {
                // This greeter supports the configured password-only PAM flow.
                if (echoResponse || root.password === "") {
                    Greetd.cancelSession();
                    root.failed("Use a text console for this prompt");
                    return;
                }
                Greetd.respond(root.password);
                root.password = "";
            } else if (error) root.errorMessage = message;
        }
        function onAuthFailure(message) { root.failed("Authentication failed"); }
        function onError(error) { root.failed("Login unavailable; try again"); }
        function onReadyToLaunch() {
            root.password = "";
            handoff.start();
        }
    }
    // Fade to black before greetd swaps compositors. Hyprland starts on
    // black and Quickshell fades the wallpaper in, so the VT gap between
    // the two hides inside the dark instead of flashing.
    SequentialAnimation {
        id: handoff
        NumberAnimation { target: veil; property: "opacity"; to: 1; duration: 350; easing.type: Easing.InQuad }
        ScriptAction {
            script: {
                // PAM/logind must know this is a graphical session before the
                // compositor starts, including for the pre-suspend lock check.
                Greetd.launch([Quickshell.env("FRED_SESSION_COMMAND")], [
                    "XDG_SESSION_TYPE=wayland",
                    "XDG_CURRENT_DESKTOP=Hyprland",
                    "XDG_SESSION_DESKTOP=Hyprland"
                ]);
            }
        }
    }
    AuthView {
        anchors.fill: parent
        theme: Theme
        busy: root.busy
        errorMessage: root.errorMessage
        onSubmitted: password => {
            if (root.busy || password === "") return;
            if (!Greetd.available) {
                root.failed("Login service unavailable");
                return;
            }
            root.errorMessage = "";
            root.password = password;
            root.busy = true;
            Greetd.createSession("fred");
        }
    }
    Rectangle { id: veil; anchors.fill: parent; color: "black"; opacity: 0 }
}