import { Link, useFetcher } from "react-router";
import { Switch } from "~/components/ui/switch";
import { Label } from "~/components/ui/label";

type ActionResult = { success?: boolean; error?: string };

function feedbackFromFetcher(fetcher: ReturnType<typeof useFetcher>) {
  if (fetcher.state !== "idle" || !fetcher.data) return { success: false, error: undefined };
  const data = fetcher.data as ActionResult;
  return { success: !!data.success, error: data.error };
}

type Props = {
  discordPingEnabled: boolean;
  hasDiscordLinked: boolean;
  draftEmailNotificationsEnabled: boolean;
};

export function NotificationsSection({ discordPingEnabled, hasDiscordLinked, draftEmailNotificationsEnabled }: Props) {
  const discordFetcher = useFetcher();
  const emailFetcher = useFetcher();

  const optimisticDiscordEnabled =
    discordFetcher.state !== "idle"
      ? discordFetcher.formData?.get("discordPingEnabled") === "true"
      : discordPingEnabled;

  const optimisticEmailEnabled =
    emailFetcher.state !== "idle"
      ? emailFetcher.formData?.get("draftEmailNotificationsEnabled") === "true"
      : draftEmailNotificationsEnabled;

  const { success: discordSuccess, error: discordError } = feedbackFromFetcher(discordFetcher);
  const { success: emailSuccess } = feedbackFromFetcher(emailFetcher);

  const handleDiscordToggle = (checked: boolean) => {
    discordFetcher.submit(
      { intent: "update-discord-ping", discordPingEnabled: String(checked) },
      { method: "post" }
    );
  };

  const handleEmailToggle = (checked: boolean) => {
    emailFetcher.submit(
      { intent: "update-email-draft-notifications", draftEmailNotificationsEnabled: String(checked) },
      { method: "post" }
    );
  };

  return (
    <div className="space-y-6">
      <div>
        <h2 className="text-lg font-semibold">Notifications</h2>
        <p className="text-sm text-muted-foreground">
          Manage how you receive league notifications.
        </p>
      </div>

      <div className="rounded-lg border p-4 space-y-4">
        <h3 className="text-sm font-medium">Draft Pick Emails</h3>
        <div className="flex items-center justify-between gap-4">
          <div className="space-y-1">
            <Label htmlFor="email-draft-switch" className="text-sm font-normal">
              Email me when I'm on the clock
            </Label>
            <p className="text-xs text-muted-foreground">
              Receive an email when it's your turn to pick in a draft. If you have back-to-back
              picks, you'll get a single email letting you know.
            </p>
          </div>
          <Switch
            id="email-draft-switch"
            checked={optimisticEmailEnabled}
            onCheckedChange={handleEmailToggle}
            disabled={emailFetcher.state !== "idle"}
          />
        </div>
        {emailSuccess && (
          <p className="text-sm text-green-600">Email notification preference saved.</p>
        )}
      </div>

      <div className="rounded-lg border p-4 space-y-4">
        <h3 className="text-sm font-medium">Discord Pings</h3>

        {!hasDiscordLinked ? (
          <p className="text-sm text-muted-foreground">
            Link your Discord account in{" "}
            <Link
              to="/settings/account"
              className="text-primary underline-offset-4 hover:underline"
            >
              Account settings
            </Link>{" "}
            to enable Discord pings for league notifications.
          </p>
        ) : (
          <>
            <div className="flex items-center justify-between gap-4">
              <div className="space-y-1">
                <Label htmlFor="discord-ping-switch" className="text-sm font-normal">
                  Ping me in standings updates
                </Label>
                <p className="text-xs text-muted-foreground">
                  When enabled, you'll be @mentioned in league Discord notifications and your
                  Discord display name will appear in place of your brackt username.
                </p>
              </div>
              <Switch
                id="discord-ping-switch"
                checked={optimisticDiscordEnabled}
                onCheckedChange={handleDiscordToggle}
                disabled={discordFetcher.state !== "idle"}
              />
            </div>
            {discordSuccess && (
              <p className="text-sm text-green-600">Notification preference saved.</p>
            )}
            {discordError && (
              <p className="text-sm text-destructive">{discordError}</p>
            )}
          </>
        )}
      </div>
    </div>
  );
}