import { Ionicons } from "@expo/vector-icons";
import { useRouter } from "expo-router";
import { useState } from "react";
import { useTranslation } from "react-i18next";
import {
  ActivityIndicator,
  Alert,
  Pressable,
  ScrollView,
  Switch,
  Text,
  TextInput,
  View,
} from "react-native";
import { useSafeAreaInsets } from "react-native-safe-area-context";
import { useHouseholdSettings, useUpdateHouseholdSettings } from "@/src/hooks/useHouseholdSettings";
import { useHouseholdMembers } from "@/src/hooks/useHouseholdMembers";

const ACCENT = "#2563EB";
const SHARE_PRESETS = [50, 60, 75, 100];

function SettingsRow({
  label,
  value,
  onPress,
}: {
  label: string;
  value: string;
  onPress: () => void;
}) {
  return (
    <Pressable
      onPress={onPress}
      className="flex-row items-center justify-between py-3 border-b border-gray-100 active:opacity-70"
    >
      <Text className="text-base text-gray-900">{label}</Text>
      <View className="flex-row items-center gap-2">
        <Text className="text-base text-gray-500">{value}</Text>
        <Ionicons name="pencil-outline" size={14} color="#9ca3af" />
      </View>
    </Pressable>
  );
}

function EditModal({
  title,
  initialValue,
  keyboardType,
  onSave,
  onClose,
}: {
  title: string;
  initialValue: string;
  keyboardType?: "default" | "decimal-pad";
  onSave: (value: string) => void;
  onClose: () => void;
}) {
  const [value, setValue] = useState(initialValue);
  const { t } = useTranslation();
  return (
    <View
      style={{
        position: "absolute", inset: 0, backgroundColor: "rgba(0,0,0,0.4)",
        alignItems: "center", justifyContent: "center", zIndex: 100,
      }}
    >
      <View className="bg-white rounded-2xl mx-6 p-5 w-full" style={{ maxWidth: 340 }}>
        <Text className="text-base font-semibold text-gray-900 mb-3">{title}</Text>
        <TextInput
          className="bg-gray-50 border border-gray-200 rounded-xl px-4 py-3 text-base text-gray-900 mb-4"
          value={value}
          onChangeText={setValue}
          keyboardType={keyboardType ?? "default"}
          autoFocus
          autoCapitalize="words"
        />
        <View className="flex-row gap-3">
          <Pressable
            onPress={onClose}
            className="flex-1 py-3 rounded-xl items-center bg-gray-100 active:opacity-70"
          >
            <Text className="text-sm font-semibold text-gray-700">{t('common.cancel')}</Text>
          </Pressable>
          <Pressable
            onPress={() => { onSave(value); onClose(); }}
            className="flex-1 py-3 rounded-xl items-center active:opacity-70"
            style={{ backgroundColor: ACCENT }}
          >
            <Text className="text-sm font-semibold text-white">{t('common.save')}</Text>
          </Pressable>
        </View>
      </View>
    </View>
  );
}

type EditingField = "ownerName" | "partnerName" | "monthlyBudget" | "userSharePercent" | null;

export default function HouseholdSettingsScreen() {
  const insets = useSafeAreaInsets();
  const router = useRouter();
  const { t } = useTranslation();
  const { data: settings, isLoading } = useHouseholdSettings();
  const { data: membersData } = useHouseholdMembers();
  const { mutate: update, isPending } = useUpdateHouseholdSettings();
  const [editing, setEditing] = useState<EditingField>(null);
  const members = membersData?.members ?? [];

  function save(input: Parameters<typeof update>[0]) {
    update(input, {
      onError: () => Alert.alert(t('common.error'), t('settings.saveError')),
    });
  }

  if (isLoading || !settings) {
    return (
      <View className="flex-1 bg-gray-50 items-center justify-center">
        <ActivityIndicator size="large" color={ACCENT} />
      </View>
    );
  }

  return (
    <View className="flex-1 bg-gray-50">
      <View
        className="bg-white border-b border-gray-100"
        style={{ paddingTop: insets.top }}
      >
        <View className="flex-row items-center px-4 py-3">
          <Pressable onPress={() => router.push("/(app)/settings")} className="mr-3 p-1">
            <Ionicons name="chevron-back" size={22} color="#374151" />
          </Pressable>
          <Text className="text-base font-semibold text-gray-900 flex-1">{t('settings.household.title')}</Text>
          {isPending && <ActivityIndicator size="small" color={ACCENT} />}
        </View>
      </View>

      <ScrollView contentContainerStyle={{ padding: 16, paddingBottom: insets.bottom + 32 }}>
        {/* Namen */}
        <View className="bg-white rounded-2xl px-4 mb-4">
          <Text className="text-xs font-medium uppercase text-gray-400 pt-3 mb-1">{t('settings.household.namesSection')}</Text>
          <SettingsRow
            label={t('settings.household.yourName')}
            value={settings.ownerName}
            onPress={() => setEditing("ownerName")}
          />
          <SettingsRow
            label={t('settings.household.partnerName')}
            value={settings.partnerName}
            onPress={() => setEditing("partnerName")}
          />
        </View>

        {/* Wer zahlt die Ausgaben vor? */}
        {members.length > 1 && (
          <View className="bg-white rounded-2xl px-4 mb-4">
            <Text className="text-xs font-medium uppercase text-gray-400 pt-3 mb-1">{t('settings.household.payerSection')}</Text>
            <Text className="text-xs text-gray-400 mb-3">{t('settings.household.payerHint')}</Text>
            <View className="flex-row gap-2 mb-3">
              {members.map((m) => {
                const isSelected = settings.payerUserId === m.userId;
                return (
                  <Pressable
                    key={m.userId}
                    onPress={() => save({ payerUserId: m.userId })}
                    className="flex-1 py-2.5 rounded-xl items-center"
                    style={{ backgroundColor: isSelected ? ACCENT : "#f3f4f6" }}
                  >
                    <Text className="text-sm font-semibold" style={{ color: isSelected ? "#fff" : "#374151" }}>
                      {m.name}
                    </Text>
                  </Pressable>
                );
              })}
            </View>
          </View>
        )}

        {/* Kostenaufteilung */}
        <View className="bg-white rounded-2xl px-4 mb-4">
          <Text className="text-xs font-medium uppercase text-gray-400 pt-3 mb-2">{t('settings.household.costSplitSection')}</Text>

          <Text className="text-xs text-gray-400 mb-3">{t('settings.household.costSplitHint')}</Text>
          <View className="flex-row gap-2 mb-3">
            {SHARE_PRESETS.map((p) => (
              <Pressable
                key={p}
                onPress={() => save({ userSharePercent: p })}
                className="flex-1 py-2.5 rounded-xl items-center"
                style={{ backgroundColor: settings.userSharePercent === p ? ACCENT : "#f3f4f6" }}
              >
                <Text
                  className="text-sm font-semibold"
                  style={{ color: settings.userSharePercent === p ? "#fff" : "#374151" }}
                >
                  {p}%
                </Text>
              </Pressable>
            ))}
          </View>

          <View
            className="rounded-xl px-3 py-2 mb-3"
            style={{ backgroundColor: "#eff6ff" }}
          >
            <Text className="text-xs text-blue-700">
              {t('settings.household.sharePreview', { own: settings.userSharePercent, partner: settings.partnerName, rest: 100 - settings.userSharePercent })}
            </Text>
          </View>

          <SettingsRow
            label={t('settings.household.monthlyBudget')}
            value={`${settings.monthlyBudget.toFixed(0)} €`}
            onPress={() => setEditing("monthlyBudget")}
          />

          <View className="flex-row items-center justify-between py-3">
            <Text className="text-base text-gray-900">{t('settings.household.splitChildren')}</Text>
            <Switch
              value={settings.splitChildCosts}
              onValueChange={(v) => save({ splitChildCosts: v })}
              trackColor={{ false: "#d1d5db", true: ACCENT }}
              thumbColor="#fff"
            />
          </View>
        </View>

        {/* Währung */}
        <View className="bg-white rounded-2xl px-4 mb-4">
          <Text className="text-xs font-medium uppercase text-gray-400 pt-3 mb-1">{t('settings.household.settingsSection')}</Text>
          <SettingsRow
            label={t('settings.household.currency')}
            value={settings.currency}
            onPress={() =>
              Alert.alert(t('settings.household.currency'), t('settings.household.currencyOnlyEur'))
            }
          />
        </View>
      </ScrollView>

      {/* Inline Edit Modals */}
      {editing === "ownerName" && (
        <EditModal
          title={t('settings.household.yourName')}
          initialValue={settings.ownerName}
          onSave={(v) => save({ ownerName: v.trim() || "Ich" })}
          onClose={() => setEditing(null)}
        />
      )}
      {editing === "partnerName" && (
        <EditModal
          title={t('settings.household.partnerName')}
          initialValue={settings.partnerName}
          onSave={(v) => save({ partnerName: v.trim() || "Partner" })}
          onClose={() => setEditing(null)}
        />
      )}
      {editing === "monthlyBudget" && (
        <EditModal
          title={t('settings.household.monthlyBudget')}
          initialValue={String(settings.monthlyBudget)}
          keyboardType="decimal-pad"
          onSave={(v) => save({ monthlyBudget: parseFloat(v.replace(",", ".")) || 400 })}
          onClose={() => setEditing(null)}
        />
      )}
    </View>
  );
}