import { Ionicons } from "@expo/vector-icons";
import { router } from "expo-router";
import { useMemo, useState } from "react";
import { Alert, Image, Pressable, Share, ScrollView, View } from "react-native";
import { useTranslation } from "react-i18next";
import { Badge } from "@/components/ui/Badge";
import { Button } from "@/components/ui/Button";
import { Card, Section } from "@/components/ui/Card";
import { DoseReminderPanel } from "@/components/ui/DoseReminderPanel";
import { EmptyState } from "@/components/ui/EmptyState";
import { Screen, TAB_BAR_INSET } from "@/components/ui/Screen";
import { TabTopBar } from "@/components/ui/TabTopBar";
import { Text } from "@/components/ui/Text";
import { routes } from "@/lib/routes";
import { useFamilyStore } from "@/lib/stores/familyStore";
import {
  usePrescriptionStore,
  type Prescription,
  type Reminder,
} from "@/lib/stores/prescriptionStore";
import { colors, gutter } from "@/lib/theme";

const statusTone = {
  submitted: "neutral",
  under_review: "warn",
  approved: "brand",
  queried: "info",
  rejected: "danger",
  filled: "brand",
} as const;

function refillDays(rx: Prescription) {
  if (!rx.lastFilledAt) return null;
  const due = new Date(rx.lastFilledAt);
  due.setDate(due.getDate() + rx.daysSupply);
  return Math.ceil((due.getTime() - Date.now()) / (1000 * 60 * 60 * 24));
}

function RxCareCard({
  rx,
  reminder,
  expanded,
  onToggleExpand,
}: {
  rx: Prescription;
  reminder?: Reminder;
  expanded: boolean;
  onToggleExpand: () => void;
}) {
  const dueIn = refillDays(rx);
  const thumb = rx.imageUris[0];

  return (
    <Card elevated style={{ padding: 0, overflow: "hidden" }}>
      <Pressable
        onPress={() => router.push(routes.rxDetail(rx.id))}
        style={{ padding: 14 }}
      >
        <View style={{ flexDirection: "row", gap: 12 }}>
          <View
            style={{
              width: 64,
              height: 64,
              borderRadius: 16,
              backgroundColor: colors.brandSoft,
              alignItems: "center",
              justifyContent: "center",
              overflow: "hidden",
            }}
          >
            {thumb ? (
              <Image source={{ uri: thumb }} style={{ width: 64, height: 64 }} />
            ) : (
              <Ionicons name="medkit" size={26} color={colors.brandText} />
            )}
          </View>
          <View style={{ flex: 1 }}>
            <View style={{ flexDirection: "row", gap: 8, alignItems: "flex-start" }}>
              <Text variant="h3" style={{ flex: 1 }} numberOfLines={2}>
                {rx.medicineName}
              </Text>
              <Badge label={rx.status.replace("_", " ")} tone={statusTone[rx.status]} />
            </View>
            <Text variant="caption" color={colors.subtle} style={{ marginTop: 4 }}>
              {rx.patientName} · {rx.medicines.length} medicine
              {rx.medicines.length === 1 ? "" : "s"} · {rx.daysSupply}d supply
            </Text>
            <View style={{ flexDirection: "row", flexWrap: "wrap", gap: 6, marginTop: 10 }}>
              {reminder?.enabled ? (
                <Badge
                  label={`Reminders ${reminder.times.join(" · ")}`}
                  tone="brand"
                  icon="alarm-outline"
                />
              ) : (
                <Badge label="No dose reminder" tone="warn" icon="alarm-outline" />
              )}
              {dueIn !== null ? (
                <Badge
                  label={
                    dueIn <= 0 ? "Refill overdue" : `Refill in ${dueIn}d`
                  }
                  tone={dueIn <= 3 ? "warn" : "neutral"}
                />
              ) : (
                <Badge label="Awaiting fill" tone="info" />
              )}
            </View>
          </View>
        </View>
      </Pressable>

      <View
        style={{
          flexDirection: "row",
          borderTopWidth: 1,
          borderTopColor: colors.line,
        }}
      >
        <Pressable
          onPress={onToggleExpand}
          style={{
            flex: 1,
            paddingVertical: 12,
            alignItems: "center",
            flexDirection: "row",
            justifyContent: "center",
            gap: 6,
          }}
        >
          <Ionicons
            name={expanded ? "chevron-up" : "notifications-outline"}
            size={16}
            color={colors.brandText}
          />
          <Text variant="label" color={colors.brandText}>
            {expanded ? "Hide setup" : reminder?.enabled ? "Edit reminder" : "Set reminder"}
          </Text>
        </Pressable>
        <View style={{ width: 1, backgroundColor: colors.line }} />
        <Pressable
          onPress={() => router.push(routes.rxCalendar(rx.id))}
          style={{
            flex: 1,
            paddingVertical: 12,
            alignItems: "center",
            flexDirection: "row",
            justifyContent: "center",
            gap: 6,
          }}
        >
          <Ionicons name="calendar-outline" size={16} color={colors.brandText} />
          <Text variant="label" color={colors.brandText}>
            Calendar
          </Text>
        </Pressable>
      </View>

      {expanded ? (
        <View style={{ paddingHorizontal: 14, paddingBottom: 14 }}>
          <DoseReminderPanel rx={rx} reminder={reminder} compact />
        </View>
      ) : null}
    </Card>
  );
}

export default function PrescriptionsTabScreen() {
  const { t } = useTranslation();
  const prescriptions = usePrescriptionStore((s) => s.prescriptions);
  const reminders = usePrescriptionStore((s) => s.reminders);
  const members = useFamilyStore((s) => s.members);
  const inviteCode = useFamilyStore((s) => s.inviteCode);
  const acceptInvite = useFamilyStore((s) => s.acceptInvite);
  const removeMember = useFamilyStore((s) => s.removeMember);
  const setActiveMember = useFamilyStore((s) => s.setActiveMember);
  const activeMemberId = useFamilyStore((s) => s.activeMemberId);
  const [expandedId, setExpandedId] = useState<string | null>(null);

  const reminderByRx = useMemo(() => {
    const map = new Map<string, Reminder>();
    reminders.forEach((r) => map.set(r.prescriptionId, r));
    return map;
  }, [reminders]);

  const activeReminderCount = reminders.filter((r) => r.enabled).length;
  const needingSetup = prescriptions.filter((p) => !reminderByRx.get(p.id)?.enabled).length;

  return (
    <Screen>
      <TabTopBar subtitle={t("common.prescriptions")} />
      <ScrollView
        showsVerticalScrollIndicator={false}
        contentContainerStyle={{
          paddingBottom: TAB_BAR_INSET + 24,
          paddingHorizontal: gutter,
          gap: 14,
        }}
      >
        <View>
          <Text variant="h1">{t("common.prescriptions")}</Text>
          <Text variant="bodySm" color={colors.subtle} style={{ marginTop: 4 }}>
            Manage Rx, dose calendars, and family care shares
          </Text>
        </View>

        <View style={{ flexDirection: "row", gap: 10 }}>
          <Card elevated={false} tone="brand" style={{ flex: 1 }}>
            <Text variant="caption" color={colors.muted}>
              Active reminders
            </Text>
            <Text variant="h1" style={{ marginTop: 2 }}>
              {activeReminderCount}
            </Text>
          </Card>
          <Card elevated={false} style={{ flex: 1 }}>
            <Text variant="caption" color={colors.muted}>
              Need setup
            </Text>
            <Text variant="h1" style={{ marginTop: 2 }}>
              {needingSetup}
            </Text>
          </Card>
        </View>

        <Button
          title={t("common.scanRx")}
          icon="scan-outline"
          onPress={() => router.push(routes.rxScan)}
        />

        <Section title="Your prescriptions">
          {prescriptions.length === 0 ? (
            <EmptyState
              compact
              icon="document-text-outline"
              title="No prescriptions yet"
              body="Scan or upload a prescription to start reminders."
              actionTitle="Scan prescription"
              onAction={() => router.push(routes.rxScan)}
            />
          ) : (
            <View style={{ gap: 12 }}>
              {prescriptions.map((rx) => (
                <RxCareCard
                  key={rx.id}
                  rx={rx}
                  reminder={reminderByRx.get(rx.id)}
                  expanded={expandedId === rx.id}
                  onToggleExpand={() =>
                    setExpandedId((cur) => (cur === rx.id ? null : rx.id))
                  }
                />
              ))}
            </View>
          )}
        </Section>

        <Section title={t("common.family")}>
          <Card tone="brand" elevated={false}>
            <View style={{ flexDirection: "row", gap: 12, alignItems: "center" }}>
              <View
                style={{
                  width: 48,
                  height: 48,
                  borderRadius: 14,
                  backgroundColor: colors.surface,
                  alignItems: "center",
                  justifyContent: "center",
                  borderWidth: 1,
                  borderColor: colors.brandBorder,
                }}
              >
                <Ionicons name="people" size={22} color={colors.brandText} />
              </View>
              <View style={{ flex: 1 }}>
                <Text variant="caption" color={colors.muted}>
                  Family invite code
                </Text>
                <Text variant="h2" style={{ marginTop: 2, letterSpacing: 1 }}>
                  {inviteCode}
                </Text>
              </View>
            </View>
            <Text variant="bodySm" color={colors.muted} style={{ marginTop: 10 }}>
              Share care so family can help with dose reminders and refills.
            </Text>
            <View style={{ flexDirection: "row", flexWrap: "wrap", gap: 8, marginTop: 12 }}>
              <Button
                title="Share code"
                size="md"
                fullWidth={false}
                variant="outline"
                icon="share-outline"
                onPress={() =>
                  Share.share({
                    message: `Join my Gishen family care group with code ${inviteCode}`,
                  })
                }
              />
              <Button
                title={t("common.inviteFamily")}
                size="md"
                fullWidth={false}
                icon="person-add-outline"
                onPress={() => router.push(routes.familyInvite)}
              />
            </View>
          </Card>

          {members.length === 0 ? (
            <Text variant="bodySm" color={colors.muted} style={{ marginTop: 8 }}>
              No family members yet. Invite someone to share Rx care.
            </Text>
          ) : (
            <View style={{ gap: 10, marginTop: 4 }}>
              {members.map((m) => {
                const active = activeMemberId === m.id;
                return (
                  <Card
                    key={m.id}
                    onPress={() => setActiveMember(active ? null : m.id)}
                    style={{
                      borderColor: active ? colors.brand : colors.line,
                      borderWidth: active ? 1.5 : 1,
                    }}
                  >
                    <View style={{ flexDirection: "row", gap: 12, alignItems: "center" }}>
                      <View
                        style={{
                          width: 42,
                          height: 42,
                          borderRadius: 21,
                          backgroundColor: colors.brandSoft,
                          alignItems: "center",
                          justifyContent: "center",
                        }}
                      >
                        <Text variant="label" color={colors.brandText}>
                          {m.name.slice(0, 1).toUpperCase()}
                        </Text>
                      </View>
                      <View style={{ flex: 1 }}>
                        <Text variant="h3">{m.name}</Text>
                        <Text variant="caption" color={colors.subtle} style={{ marginTop: 2 }}>
                          {m.relationship}
                          {m.phone ? ` · ${m.phone}` : ""}
                          {active ? " · Active for Rx" : ""}
                        </Text>
                      </View>
                      <Badge
                        label={m.status}
                        tone={m.status === "accepted" ? "brand" : "warn"}
                      />
                    </View>
                    <View
                      style={{
                        flexDirection: "row",
                        flexWrap: "wrap",
                        gap: 8,
                        marginTop: 12,
                      }}
                    >
                      {m.status === "pending" ? (
                        <Button
                          title="Accept"
                          size="sm"
                          fullWidth={false}
                          onPress={() => acceptInvite(m.id)}
                        />
                      ) : null}
                      <Button
                        title="Remove"
                        size="sm"
                        variant="ghost"
                        fullWidth={false}
                        onPress={() =>
                          Alert.alert("Remove member?", m.name, [
                            { text: "Cancel", style: "cancel" },
                            {
                              text: "Remove",
                              style: "destructive",
                              onPress: () => removeMember(m.id),
                            },
                          ])
                        }
                      />
                    </View>
                  </Card>
                );
              })}
            </View>
          )}
        </Section>
      </ScrollView>
    </Screen>
  );
}