function show(platform, enabled, useSettingsInsteadOfPreferences) {
    document.body.classList.add(`platform-${platform}`);

    if (useSettingsInsteadOfPreferences) {
        document.getElementsByClassName('platform-mac state-on')[0].innerText =
            'Nostore’s extension is currently on. You can turn it off in the Extensions section of Safari Settings.';
        document.getElementsByClassName('platform-mac state-off')[0].innerText =
            'Nostore’s extension is currently off. You can turn it on in the Extensions section of Safari Settings.';
        document.getElementsByClassName(
            'platform-mac state-unknown'
        )[0].innerText =
            'You can turn on Nostore’s extension in the Extensions section of Safari Settings.';
        document.getElementsByClassName(
            'platform-mac open-preferences'
        )[0].innerText = 'Quit and Open Safari Settings…';
    }

    if (typeof enabled === 'boolean') {
        document.body.classList.toggle(`state-on`, enabled);
        document.body.classList.toggle(`state-off`, !enabled);
    } else {
        document.body.classList.remove(`state-on`);
        document.body.classList.remove(`state-off`);
    }
}

function openPreferences() {
    webkit.messageHandlers.controller.postMessage('open-preferences');
}

document
    .querySelector('button.open-preferences')
    .addEventListener('click', openPreferences);