(function ()()

in beta/src/pages/_document.tsx [17:53]

• 17 lines of code
• 6 McCabe index (conditional complexity)

                (function () {
                  function setTheme(newTheme) {
                    window.__theme = newTheme;
                    if (newTheme === 'dark') {
                      document.documentElement.classList.add('dark');
                    } else if (newTheme === 'light') {
                      document.documentElement.classList.remove('dark');
                    }
                  }

                  var preferredTheme;
                  try {
                    preferredTheme = localStorage.getItem('theme');
                  } catch (err) { }

                  window.__setPreferredTheme = function(newTheme) {
                    preferredTheme = newTheme;
                    setTheme(newTheme);
                    try {
                      localStorage.setItem('theme', newTheme);
                    } catch (err) { }
                  };

                  var initialTheme = preferredTheme;
                  var darkQuery = window.matchMedia('(prefers-color-scheme: dark)');

                  if (!initialTheme) {
                    initialTheme = darkQuery.matches ? 'dark' : 'light';
                  }
                  setTheme(initialTheme);

                  darkQuery.addEventListener('change', function (e) {
                    if (!preferredTheme) {
                      setTheme(e.matches ? 'dark' : 'light');
                    }
                  });
                })();