@stencil/router/dist/collection/utils/createTransitionManager.js

// Adapted from the https://github.com/ReactTraining/history and converted to TypeScript
import { warning } from './log';
const createTransitionManager = () => {
    let prompt;
    let listeners = [];
    const setPrompt = (nextPrompt) => {
        warning(prompt == null, 'A history supports only one prompt at a time');
        prompt = nextPrompt;
        return () => {
            if (prompt === nextPrompt) {
                prompt = null;
            }
        };
    };
    const confirmTransitionTo = (location, action, getUserConfirmation, callback) => {
        // TODO: If another transition starts while we're still confirming
        // the previous one, we may end up in a weird state. Figure out the
        // best way to handle this.
        if (prompt != null) {
            const result = typeof prompt === 'function' ? prompt(location, action) : prompt;
            if (typeof result === 'string') {
                if (typeof getUserConfirmation === 'function') {
                    getUserConfirmation(result, callback);
                }
                else {
                    warning(false, 'A history needs a getUserConfirmation function in order to use a prompt message');
                    callback(true);
                }
            }
            else {
                // Return false from a transition hook to cancel the transition.
                callback(result !== false);
            }
        }
        else {
            callback(true);
        }
    };
    const appendListener = (fn) => {
        let isActive = true;
        const listener = (...args) => {
            if (isActive) {
                fn(...args);
            }
        };
        listeners.push(listener);
        return () => {
            isActive = false;
            listeners = listeners.filter(item => item !== listener);
        };
    };
    const notifyListeners = (...args) => {
        listeners.forEach(listener => listener(...args));
    };
    return {
        setPrompt,
        confirmTransitionTo,
        appendListener,
        notifyListeners
    };
};
export default createTransitionManager;