import { i18n } from "@lingui/core";
import { useLingui } from "@lingui/react/macro";
import type { CoachRhythm } from "@rakazo/contracts";
import {
  Button,
  Input,
  NativeSelect,
  NativeSelectOption,
  Popover,
  PopoverContent,
  PopoverTrigger,
  Spinner,
  Switch,
} from "@rakazo/ui-web";
import { CalendarClock } from "lucide-react";
import type { ReactNode } from "react";
import { useCallback, useId, useRef, useState } from "react";
import { rpc } from "../../lib/rpc";

/** Times a check-in starts at when it is switched on. */
const DEFAULTS = { morning: "08:00", evening: "20:00", weekly: { day: 0, time: "18:00" } };
const WEEKDAYS = [0, 1, 2, 3, 4, 5, 6];

function weekdayName(day: number): string {
  // 2026-10-04 was a Sunday, so day 0 maps to Sunday.
  return new Date(Date.UTC(2026, 9, 4 + day)).toLocaleDateString(i18n.locale || "en", {
    weekday: "long",
    timeZone: "UTC",
  });
}

/** When the main bot checks in: loaded when opened, saved on every change. */
export function CoachRhythmControl() {
  const { t } = useLingui();
  const [rhythm, setRhythm] = useState<CoachRhythm | null>(null);
  const latestRequest = useRef(0);

  const load = useCallback(async () => {
    const request = ++latestRequest.current;
    try {
      const loaded = await rpc.coach.rhythm.get();
      if (request === latestRequest.current) setRhythm(loaded);
    } catch {
      // Opening the control again retries.
    }
  }, []);

  const save = useCallback(
    async (next: CoachRhythm) => {
      setRhythm(next);
      const request = ++latestRequest.current;
      try {
        const saved = await rpc.coach.rhythm.set(next);
        if (request === latestRequest.current) setRhythm(saved);
      } catch {
        if (request === latestRequest.current) void load();
      }
    },
    [load],
  );

  return (
    <Popover
      onOpenChange={(open) => {
        if (open) void load();
      }}
    >
      <PopoverTrigger
        data-testid="heute-rhythm"
        aria-label={t`Check-ins`}
        title={t`Check-ins`}
        render={<Button variant="ghost" size="icon" />}
      >
        <CalendarClock strokeWidth={1.7} aria-hidden="true" />
      </PopoverTrigger>
      <PopoverContent
        align="end"
        sideOffset={8}
        data-testid="heute-rhythm-panel"
        className="w-[min(340px,calc(100vw-2rem))] gap-3 p-3"
      >
        {rhythm ? (
          <>
            <RhythmRow
              label={t`Morning`}
              testId="heute-rhythm-morning"
              on={rhythm.morning !== null}
              onToggle={(on) => void save({ ...rhythm, morning: on ? DEFAULTS.morning : null })}
            >
              {(labelId) =>
                rhythm.morning ? (
                  <TimeInput
                    labelId={labelId}
                    value={rhythm.morning}
                    onChange={(morning) => void save({ ...rhythm, morning })}
                  />
                ) : null
              }
            </RhythmRow>
            <RhythmRow
              label={t`Evening`}
              testId="heute-rhythm-evening"
              on={rhythm.evening !== null}
              onToggle={(on) => void save({ ...rhythm, evening: on ? DEFAULTS.evening : null })}
            >
              {(labelId) =>
                rhythm.evening ? (
                  <TimeInput
                    labelId={labelId}
                    value={rhythm.evening}
                    onChange={(evening) => void save({ ...rhythm, evening })}
                  />
                ) : null
              }
            </RhythmRow>
            <RhythmRow
              label={t`Weekly`}
              testId="heute-rhythm-weekly"
              on={rhythm.weekly !== null}
              onToggle={(on) => void save({ ...rhythm, weekly: on ? DEFAULTS.weekly : null })}
            >
              {(labelId) => {
                const weekly = rhythm.weekly;
                if (!weekly) return null;
                return (
                  <>
                    <NativeSelect
                      size="sm"
                      aria-labelledby={labelId}
                      value={String(weekly.day)}
                      onChange={(event) =>
                        void save({
                          ...rhythm,
                          weekly: { ...weekly, day: Number(event.target.value) },
                        })
                      }
                    >
                      {WEEKDAYS.map((day) => (
                        <NativeSelectOption key={day} value={day}>
                          {weekdayName(day)}
                        </NativeSelectOption>
                      ))}
                    </NativeSelect>
                    <TimeInput
                      labelId={labelId}
                      value={weekly.time}
                      onChange={(time) => void save({ ...rhythm, weekly: { ...weekly, time } })}
                    />
                  </>
                );
              }}
            </RhythmRow>
          </>
        ) : (
          <div className="flex justify-center py-3">
            <Spinner />
          </div>
        )}
      </PopoverContent>
    </Popover>
  );
}

function RhythmRow({
  label,
  testId,
  on,
  onToggle,
  children,
}: {
  label: string;
  testId: string;
  on: boolean;
  onToggle: (on: boolean) => void;
  children: (labelId: string) => ReactNode;
}) {
  const labelId = useId();
  return (
    <div data-testid={testId} className="flex min-h-control-sm flex-wrap items-center gap-2">
      <Switch
        size="sm"
        checked={on}
        aria-labelledby={labelId}
        onCheckedChange={(checked) => onToggle(checked)}
      />
      <span id={labelId} className="flex-1 text-ui-body text-foreground">
        {label}
      </span>
      <div className="ml-auto flex items-center gap-2">{children(labelId)}</div>
    </div>
  );
}

function TimeInput({
  labelId,
  value,
  onChange,
}: {
  labelId: string;
  value: string;
  onChange: (value: string) => void;
}) {
  return (
    <Input
      type="time"
      aria-labelledby={labelId}
      value={value}
      onChange={(event) => {
        if (event.target.value) onChange(event.target.value.slice(0, 5));
      }}
      className="h-control-sm w-32 px-2 tabular-nums"
    />
  );
}