// The topics of the Alex2MQTT contract, named once. The backend and Alex2ESP use the same names, so none of them
// can change here alone.
/** Where the backend asks for the endpoints of the root. */
export const discover = (root) => `${root}/discover`;
/** Where the bridge answers a discovery request with its endpoints. */
export const discoverReply = (root) => `${root}/discover_r`;
/** Where the backend publishes the directives for one endpoint. */
export const directive = (root, endpointId) => `${root}/${endpointId}/alexaDirective`;
/**
 * What the bridge subscribes to: the discovery requests and the directives of every endpoint. Not <root>/#, which
 * also delivers what the bridge itself publishes and the backend's <endpointId>/alexaDirective_e.
 */
export const subscriptions = (root) => [discover(root), directive(root, "+")];
/** The endpointId of a directive topic, null for any other topic. */
export function directiveEndpoint(root, topic) {
    const [, endpointId, ...rest] = topic.startsWith(`${root}/`) ? topic.slice(root.length).split("/") : [];
    return endpointId && rest.length === 1 && rest[0] === "alexaDirective" ? endpointId : null;
}
/** Where the answer to a directive goes. "alexaResponce" is how the backend and Alex2ESP spell it. */
export const response = (root, endpointId) => `${root}/${endpointId}/alexaResponce`;
/** Where the answer goes once a DeferredResponse was sent for the directive. */
export const deferred = (root, endpointId) => `${root}/${endpointId}/deferredResponse`;
/** Where every ChangeReport of the root goes: the backend adds the user's token and posts it to Alexa. */
export const changeReport = (root) => `${root}/changeReport`;