defmodule DarkMode do
  use Phoenix.Component

  def button(assigns) do
    ~H"""
    <button
      id="theme-toggle"
      type="button"
      phx-update="ignore"
      phx-hook="DarkThemeToggle"
      class="text-foreground hover:bg-foreground/10 rounded-lg text-sm p-2 drop-shadow-md"
      aria-label="Toggle dark/light mode"
    >
      <svg
        id="theme-toggle-dark-icon"
        class="w-5 h-5 text-transparent hidden"
        fill="currentColor"
        viewBox="0 0 20 20"
        xmlns="http://www.w3.org/2000/svg"
      >
        <title>Toggle light mode</title>
        <path d="M17.293 13.293A8 8 0 016.707 2.707a8.001 8.001 0 1010.586 10.586z"></path>
      </svg>

      <svg
        id="theme-toggle-light-icon"
        class="w-5 h-5 text-transparent"
        fill="currentColor"
        viewBox="0 0 20 20"
        xmlns="http://www.w3.org/2000/svg"
      >
        <title>Toggle dark mode</title>
        <path
          d="M10 2a1 1 0 011 1v1a1 1 0 11-2 0V3a1 1 0 011-1zm4 8a4 4 0 11-8 0 4 4 0 018 0zm-.464 4.95l.707.707a1 1 0 001.414-1.414l-.707-.707a1 1 0 00-1.414 1.414zm2.12-10.607a1 1 0 010 1.414l-.706.707a1 1 0 11-1.414-1.414l.707-.707a1 1 0 011.414 0zM17 11a1 1 0 100-2h-1a1 1 0 100 2h1zm-7 4a1 1 0 011 1v1a1 1 0 11-2 0v-1a1 1 0 011-1zM5.05 6.464A1 1 0 106.465 5.05l-.708-.707a1 1 0 00-1.414 1.414l.707.707zm1.414 8.486l-.707.707a1 1 0 01-1.414-1.414l.707-.707a1 1 0 011.414 1.414zM4 11a1 1 0 100-2H3a1 1 0 000 2h1z"
          fill-rule="evenodd"
          clip-rule="evenodd"
        >
        </path>
      </svg>
    </button>

    <script>
      // Toggle early based on <html class="dark">
      const themeToggleDarkIcon = document.getElementById('theme-toggle-dark-icon');
      const themeToggleLightIcon = document.getElementById('theme-toggle-light-icon');
      if (themeToggleDarkIcon != null && themeToggleLightIcon != null) {
        let dark = document.documentElement.classList.contains('dark');
        const show = dark ? themeToggleDarkIcon : themeToggleLightIcon
        const hide = dark ? themeToggleLightIcon : themeToggleDarkIcon
        show.classList.remove('hidden', 'text-transparent');
        hide.classList.add('hidden', 'text-transparent');
      }
    </script>
    """
  end
end
