import { useMemo, useState } from "react";
import { Alert, View } from "react-native";
import { Badge } from "@/components/ui/Badge";
import { Button } from "@/components/ui/Button";
import { Chip } from "@/components/ui/Chip";
import { SwitchRow } from "@/components/ui/Field";
import { Text } from "@/components/ui/Text";
import { scheduleDailyDoseReminders } from "@/lib/notifications";
import { useEmergencyContactStore } from "@/lib/stores/emergencyContactStore";
import { useNotificationStore } from "@/lib/stores/notificationStore";
import {
  usePrescriptionStore,
  type Prescription,
  type Reminder,
} from "@/lib/stores/prescriptionStore";
import { colors, radii } from "@/lib/theme";
import { routes } from "@/lib/routes";

const PRESETS = ["08:00", "12:00", "14:00", "18:00", "20:00"] as const;

export function DoseReminderPanel({
  rx,
  reminder,
  compact,
  onScheduled,
}: {
  rx: Prescription;
  reminder?: Reminder | null;
  compact?: boolean;
  onScheduled?: () => void;
}) {
  const upsertReminder = usePrescriptionStore((s) => s.upsertReminder);
  const schedulePendingDose = usePrescriptionStore((s) => s.schedulePendingDose);
  const grace = useEmergencyContactStore((s) => s.graceMinutesDefault);
  const escalationEnabled = useEmergencyContactStore((s) => s.escalationEnabled);
  const setEscalationEnabled = useEmergencyContactStore((s) => s.setEscalationEnabled);
  const contacts = useEmergencyContactStore((s) => s.contacts);
  const pushNotification = useNotificationStore((s) => s.push);

  const [times, setTimes] = useState(
    reminder?.times?.length ? reminder.times.join(",") : "08:00,20:00"
  );
  const [busy, setBusy] = useState(false);

  const selected = useMemo(
    () =>
      times
        .split(",")
        .map((s) => s.trim())
        .filter(Boolean),
    [times]
  );

  const togglePreset = (t: string) => {
    if (selected.includes(t)) {
      setTimes(selected.filter((x) => x !== t).join(","));
    } else {
      setTimes([...selected, t].sort().join(","));
    }
  };

  const save = async () => {
    if (!selected.length) {
      Alert.alert("Pick a time", "Choose at least one dose time.");
      return;
    }
    setBusy(true);
    try {
      const reminderId = `rem_${rx.id}`;
      upsertReminder({
        id: reminderId,
        prescriptionId: rx.id,
        medicineName: rx.medicineName,
        times: selected,
        daysOfWeek: [0, 1, 2, 3, 4, 5, 6],
        graceMinutes: grace,
        escalateOnMiss: escalationEnabled,
        enabled: true,
        memberId: rx.memberId,
      });

      const result = await scheduleDailyDoseReminders({
        prescriptionId: rx.id,
        medicineName: rx.medicineName,
        times: selected,
      });

      schedulePendingDose(reminderId);

      pushNotification({
        kind: "dose",
        title: `Reminders on · ${rx.medicineName}`,
        body: result.granted
          ? `Daily push at ${result.times.join(", ")}. Demo ping in ~12s.`
          : `Saved ${result.times.join(", ")}. Enable notification permission for push.`,
        href: routes.rxCalendar(rx.id),
      });

      Alert.alert(
        result.granted ? "Reminders scheduled" : "Reminders saved",
        result.granted
          ? `Calendar push notifications set for ${result.times.join(", ")}. You'll get a demo notification shortly.`
          : `Times saved (${result.times.join(", ")}). Allow notifications to receive daily push alerts.`
      );
      onScheduled?.();
    } finally {
      setBusy(false);
    }
  };

  return (
    <View
      style={
        compact
          ? {
              marginTop: 12,
              paddingTop: 12,
              borderTopWidth: 1,
              borderTopColor: colors.line,
              gap: 10,
            }
          : { gap: 12 }
      }
    >
      <View style={{ flexDirection: "row", alignItems: "center", gap: 8 }}>
        <Text variant="h3" style={{ flex: 1 }}>
          Dose times
        </Text>
        {reminder?.enabled ? <Badge label="Active" tone="brand" /> : <Badge label="Not set" tone="neutral" />}
      </View>
      {!compact ? (
        <Text variant="caption" color={colors.muted}>
          Pick daily times. We’ll schedule calendar push notifications for each slot.
        </Text>
      ) : null}

      <View style={{ flexDirection: "row", flexWrap: "wrap", gap: 8 }}>
        {PRESETS.map((p) => (
          <Chip
            key={p}
            label={p}
            selected={selected.includes(p)}
            onPress={() => togglePreset(p)}
            size="sm"
          />
        ))}
      </View>

      {selected.length ? (
        <View
          style={{
            flexDirection: "row",
            flexWrap: "wrap",
            gap: 6,
            padding: 10,
            borderRadius: radii.md,
            backgroundColor: colors.brandWash,
            borderWidth: 1,
            borderColor: colors.brandBorder,
          }}
        >
          <Text variant="caption" color={colors.brandText}>
            Schedule: {selected.join(" · ")} every day
          </Text>
        </View>
      ) : null}

      {!compact ? (
        <View
          style={{
            borderRadius: radii.md,
            borderWidth: 1,
            borderColor: colors.line,
            overflow: "hidden",
            backgroundColor: colors.surface,
          }}
        >
          <SwitchRow
            icon="notifications-outline"
            title="Escalate if missed"
            subtitle={
              contacts[0]
                ? `Notify ${contacts[0].name} after grace`
                : "Add an emergency contact in profile"
            }
            value={escalationEnabled}
            onValueChange={setEscalationEnabled}
            last
          />
        </View>
      ) : null}

      <Button
        title={busy ? "Scheduling…" : "Save & enable push"}
        icon="alarm-outline"
        onPress={save}
        disabled={busy}
        size={compact ? "md" : "lg"}
      />
    </View>
  );
}