gnome-shell/js/ui/realms/realmWindowMenu.js

const { Shell, GObject } = imports.gi;

const PopupMenu = imports.ui.popupMenu;

function _windowAppId(window) {
    const tracker = Shell.WindowTracker.get_default();
    const app = tracker.get_window_app(window);
    if (app) {
        return app.get_id();
    } else {
        log(`No app found for window ${window.get_description()}`)
        return null;
    }
}

function windowMenuDebugString(window) {
    const id = _windowAppId(window);
    const realm_name = windowRealmName(window);

    if (!realm_name) {
        return id;
    } else if (window.is_on_foreign_workspace_context()) {
        return `${id} [${realm_name}]`;
    } else {
        return `${id} (${realm_name})`;
    }
}

function _createMoveWindowItem(label, realm_name, window) {
    let item = new PopupMenu.PopupMenuItem(label);
    item.connect('activate', () => {
        let realms = Shell.Realms.get_default();
        let realm = realms.realm_by_name(realm_name);

        if (realm) {
            realm.move_window_to_context(window);
        }
    });
    return item;
}

// Return name of the realm the application this window belongs to is running in.
function windowRealmName(window) {
    const realms = Shell.Realms.get_default();

    if (realms.is_citadel_window(window)) {
        return "Citadel"
    }

    let realm = realms.realm_by_window(window);

    if (realm) {
        return realm.realm_name;
    } else {
        return null;
    }
}

// Return name of realm the context this window is currently located on belongs to
function windowContextRealmName(window) {
    if (window.on_all_workspaces) {
        return windowRealmName(window);
    }

    let ws = window.get_workspace();

    if (!ws) {
        return null;
    }
    const realms = Shell.Realms.get_default();
    let realm = realms.realm_by_context_id(ws.get_context_id());

    if (realm) {
        return realm.realm_name;
    } else {
        return null;
    }
}
function enableFrameItem(window) {
    const realms = Shell.Realms.get_default();
    const frames = realms.window_frames();
    if (!frames.has_frame(window)) {
        return null;
    }
    let enabled = frames.is_frame_enabled(window);
    let item = new PopupMenu.PopupMenuItem("Display colored window frame");
    if (enabled) {
        item.setOrnament(PopupMenu.Ornament.CHECK);
    }

    item.connect('activate', () => {
        let realms = Shell.Realms.get_default();
        const frames = realms.window_frames();
        frames.set_frame_enabled(window, !enabled);
    });

    return item;
}

function realmWindowMenu(window) {

    const realm_name = windowContextRealmName(window);

    if (!realm_name) {
        return null;
    }

    const realms = Shell.Realms.get_default();
    let other_realms = [];

    let running_realms = realms.get_running_realms();
    running_realms.forEach(realm => {
        if (realm.realm_name != realm_name) {
            other_realms.push(realm.realm_name);
        }
    });

    if (other_realms.length == 0) {
        return null;
    } else if (other_realms.length == 1) {
        let name = other_realms[0];
        return _createMoveWindowItem(`Move to realm-${name}`, name, window);
    }

    let subMenu = new PopupMenu.PopupSubMenuMenuItem('Move to Realm...', true);

    other_realms.forEach(name => {
        let item = _createMoveWindowItem(`realm-${name}`, name, window);
        subMenu.menu.addMenuItem(item);
    });
    return subMenu;
}