import { FormMessage, SettingRow } from "./design-system/WorkspacePanel";
import { useEffect, useRef, useState } from "react";
import { habitRequest } from "../lib/dashboard";
import { allWeekdays, defaultReminder, entries, type ReminderEntry, type ReminderResponse } from "../reminders/contracts";
import { Button, Checkbox } from "./design-system/primitives";
import { Field } from "./design-system/Field";

const deliveryLabels: Record<string, string> = {
  sent: "Delivered", deferred: "Waiting to retry", pending: "Delivery unconfirmed", uncertain: "Delivery unconfirmed; check Discord. This reminder will not be retried.",
  failed: "Discord could not deliver it. Check your DM permissions and that you share a server with the bot.", skipped: "Skipped because your check-ins or settings changed",
};
export function ReminderSettings({ timezone, onBusyChange, disabled = false }: { timezone: string; onBusyChange?: (busy: boolean) => void; disabled?: boolean }) {
  const [settings, setSettings] = useState<ReminderResponse>();
  const [draft, setDraft] = useState({ ...defaultReminder, reminders: entries(defaultReminder) });
  const [error, setError] = useState("");
  const [notice, setNotice] = useState("");
  const [busy, setBusy] = useState(false);
  const [attempt, setAttempt] = useState(0);
  const saving = useRef(false);
  useEffect(() => {
    const controller = new AbortController(); setError("");
    habitRequest<ReminderResponse>("/reminders", { signal: controller.signal })
      .then(data => { if (!controller.signal.aborted) { setSettings(data); setDraft({ enabled: data.enabled, time: data.time ?? "20:00", reminders: entries(data), quietStart: data.quietStart, quietEnd: data.quietEnd }); } })
      .catch(error => { if (!controller.signal.aborted) setError(error.message); });
    return () => controller.abort();
  }, [attempt]);
  const changeEntry = (index: number, entry: ReminderEntry) => setDraft(value => ({ ...value, reminders: value.reminders.map((previous, position) => position === index ? entry : previous) }));
  return <SettingRow title="Reminders" description={<><p>A private Discord nudge when you still have habits left today. Named reminders include their name in the message. No habit names are sent.</p><p className="ds-meta-label">Times in {timezone}</p></>}>
    {!settings ? error ? <Button variant="secondary" onClick={() => setAttempt(value => value + 1)}>Reload reminders</Button> : <p className="ds-supporting-copy" role="status">Loading reminders…</p> : <form className="ds-form-stack" onSubmit={async event => {
      event.preventDefault(); if (saving.current || disabled) return;
      const form = event.currentTarget;
      const submitted = { enabled: draft.enabled, reminders: draft.reminders.map((entry, index) => ({ ...entry, time: (form.elements.namedItem(`reminder-time-${index}`) as HTMLInputElement).value, ...(entry.type === "date" ? { date: (form.elements.namedItem(`reminder-date-${index}`) as HTMLInputElement).value } : {}) })), quietStart: draft.quietStart, quietEnd: draft.quietEnd, ...Object.fromEntries((["quietStart", "quietEnd"] as const).map(key => [key, (form.elements.namedItem(key) as HTMLInputElement).value])) };
      saving.current = true; setBusy(true); onBusyChange?.(true); setError(""); setNotice("");
      try {
        await habitRequest("/reminders", { method: "PUT", headers: { "Content-Type": "application/json" }, body: JSON.stringify(submitted) });
        setDraft(value => ({ ...value, ...submitted }));
        setNotice(submitted.enabled ? "Discord reminders saved." : "Reminders turned off.");
      } catch (error) { setError(error instanceof Error ? error.message : "Could not save reminders. Try again."); }
      finally { saving.current = false; setBusy(false); onBusyChange?.(false); }
    }}>
      {!settings.available && <p className="ds-supporting-copy">Discord reminders are not configured on this server.</p>}
      <fieldset className="ds-inline-item-fields ds-form-stack" disabled={busy || disabled}>
        <Checkbox className="ds-preference-toggle" description="Choose when to receive a nudge. Turn off anytime." label="Enable Discord reminders" checked={draft.enabled} disabled={!settings.available && !draft.enabled} onChange={event => setDraft(value => ({ ...value, enabled: event.target.checked }))} />
        {draft.reminders.map((entry, index) => <div key={index} className="ds-form-stack">
          <Field label={`Reminder ${index + 1} name (optional)`}>{id => <input id={id} value={entry.name ?? ""} placeholder="e.g. Morning check-in" maxLength={80} onChange={event => changeEntry(index, { ...entry, name: event.target.value })} />}</Field>
          <div className="ds-clock-fields">
            <Field label={`Reminder ${index + 1} time`}>{id => <input id={id} name={`reminder-time-${index}`} type="time" required value={entry.time} onInput={event => changeEntry(index, { ...entry, time: event.currentTarget.value })} />}</Field>
            <Field label="Repeat">{id => <select id={id} value={entry.type} onChange={event => changeEntry(index, event.target.value === "date" ? { type: "date", name: entry.name, time: entry.time, date: "" } : { type: "weekly", name: entry.name, time: entry.time, days: allWeekdays })}><option value="weekly">Weekdays</option><option value="date">Specific date</option></select>}</Field>
          </div>
          {entry.type === "date" ? <Field label="Date">{id => <input id={id} name={`reminder-date-${index}`} type="date" required value={entry.date} onInput={event => changeEntry(index, { ...entry, date: event.currentTarget.value })} />}</Field> :
            <div className="ds-action-row" role="group" aria-label={`Reminder ${index + 1} weekdays`}>{[[1, "Mon"], [2, "Tue"], [3, "Wed"], [4, "Thu"], [5, "Fri"], [6, "Sat"], [0, "Sun"]].map(([day, label]) => <Checkbox key={day} label={String(label)} checked={entry.days.includes(Number(day))} onChange={event => changeEntry(index, { ...entry, days: event.target.checked ? [...entry.days, Number(day)] : entry.days.filter(value => value !== day) })} />)}</div>}
          <Button variant="text" disabled={draft.reminders.length === 1} onClick={() => setDraft(value => ({ ...value, reminders: value.reminders.filter((_, position) => position !== index) }))}>Remove reminder {index + 1}</Button>
        </div>)}
        <Button variant="secondary" disabled={draft.reminders.length >= 20} onClick={() => setDraft(value => ({ ...value, reminders: [...value.reminders, { type: "weekly", time: "20:00", days: allWeekdays }] }))}>Add reminder</Button>
        <div className="ds-clock-fields">
          {([['quietStart', 'Quiet hours start'], ['quietEnd', 'Quiet hours end']] as const).map(([key, label]) =>
            <Field key={key} label={label}>{id => <input id={id} name={key} type="time" required defaultValue={draft[key]} />}</Field>)}
        </div>
        <div className="ds-action-row"><Button type="submit" variant="secondary" disabled={busy || disabled}>{busy ? "Saving…" : "Save reminders"}</Button></div>
      </fieldset>
      {settings.lastDelivery && <p className="ds-delivery-note"><span className="ds-eyebrow">LAST REMINDER</span><span>{settings.lastDelivery.date}: {deliveryLabels[settings.lastDelivery.status] ?? "Unknown delivery status"}</span></p>}
    </form>}
    <FormMessage error>{error}</FormMessage>
    <FormMessage>{notice}</FormMessage>
  </SettingRow>;
}