/*
 * USMT Dash - page routes
 *
 * Every page in the nav has its own address, so links, bookmarks, new tabs and the
 * browser's back / forward buttons land on the right page without loading the home page
 * first:  /  (Overview)  /tracked  /workbench  /status  /devices  /custom  /docs  /docs/<title>
 * The server answers all of these with the dashboard itself.
 */
(function () {
    'use strict';

    const ROUTES = {
        'overview': '/',
        'tracked-devices': '/tracked',
        'workbench': '/workbench',
        'all-devices': '/status',
        'software': '/devices',
        'custom': '/custom',
        'docs': '/docs'
    };
    const ALIASES = { '/overview': 'overview', '/home': 'overview' };

    function pageFor(path) {
        path = (path || '/').replace(/\/+$/, '') || '/';
        if (path === '/docs' || path.startsWith('/docs/')) return 'docs';
        if (ALIASES[path]) return ALIASES[path];
        return Object.keys(ROUTES).find(id => ROUTES[id] === path) || null;
    }
    const docTitle = () => (typeof currentDocTitle !== 'undefined' && currentDocTitle) ? currentDocTitle : '';
    function pathFor(id) {
        if (id === 'docs') {
            if (location.pathname.startsWith('/docs/')) return location.pathname;   // docs.js already set the article
            return docTitle() ? '/docs/' + encodeURIComponent(docTitle()) : '/docs';
        }
        return ROUTES[id] || '/';
    }

    let quiet = false;   // true while following the address bar (no new history entries)
    function go(id) {
        if (!ROUTES[id]) return;
        const path = pathFor(id);
        if (quiet || location.pathname === path) return;
        try { history.pushState({ page: id }, '', path + location.hash); } catch (e) {}
    }

    function follow() {
        const id = pageFor(location.pathname);
        if (!id) return;
        quiet = true;
        try {
            if (id === 'docs') {
                const m = location.pathname.match(/^\/docs\/(.+)$/);
                let title = null;
                if (m) { try { title = decodeURIComponent(m[1]); } catch (e) {} }
                if (!(title && window.KB && KB.open(title))) switchPage('docs');
            } else {
                switchPage(id);
            }
        } finally { quiet = false; }
    }

    document.addEventListener('DOMContentLoaded', () => {
        const orig = window.switchPage;
        if (typeof orig !== 'function') return;
        window.switchPage = function (id) {
            const r = orig.apply(this, arguments);
            go(id);
            return r;
        };
        // Open the page in the address bar right away (articles open once the list has loaded)
        const id = pageFor(location.pathname);
        if (id && id !== 'overview' && id !== 'docs') { quiet = true; try { orig(id); } finally { quiet = false; } }
        if (id === 'docs' && location.pathname === '/docs') { quiet = true; try { orig('docs'); } finally { quiet = false; } }
        window.addEventListener('popstate', follow);
    });
})();