import { createApiClient } from '@pipu/api-client';
import { checkServer, normalizeServerUrl, type ServerCheck } from '@pipu/core';
import Constants from 'expo-constants';
import { useState } from 'react';
import { useTranslation } from 'react-i18next';
import { ActivityIndicator, Pressable, StyleSheet, Text, TextInput, View } from 'react-native';

import { colors, radius } from './theme';

const appVersionCode = Number(Constants.expoConfig?.extra?.versionCode ?? 0);

type State = { kind: 'idle' } | { kind: 'checking' } | { kind: 'invalid' } | ({ kind: 'done' } & ServerCheck);

/** Экран подключения к серверу (docs/mobile.md). В M0 — только проверка /server-info. */
export function ConnectScreen() {
  const { t } = useTranslation();
  const [address, setAddress] = useState('');
  const [state, setState] = useState<State>({ kind: 'idle' });

  const checking = state.kind === 'checking';

  async function onCheck() {
    if (checking) return;
    const baseUrl = normalizeServerUrl(address);
    if (!baseUrl) {
      setState({ kind: 'invalid' });
      return;
    }
    setState({ kind: 'checking' });
    const res = await checkServer(createApiClient({ baseUrl }), appVersionCode);
    setState({ kind: 'done', ...res });
  }

  return (
    <View style={styles.screen}>
      <View style={styles.card}>
        <Text style={styles.title}>{t('app.name')}</Text>
        <Text style={styles.muted}>{t('app.tagline')}</Text>

        <Text style={styles.label}>{t('server.address')}</Text>
        <TextInput
          value={address}
          onChangeText={setAddress}
          onSubmitEditing={onCheck}
          editable={!checking}
          placeholder="https://music.home.lan"
          placeholderTextColor={colors.text3}
          autoCapitalize="none"
          autoCorrect={false}
          keyboardType="url"
          style={styles.input}
        />

        {state.kind === 'checking' && (
          <View style={[styles.status, { backgroundColor: colors.surface2 }]}>
            <ActivityIndicator color={colors.text2} />
            <Text style={{ color: colors.text2 }}>{t('server.checking')}</Text>
          </View>
        )}
        {state.kind === 'invalid' && <Status ok={false} text={t('server.invalid_address')} />}
        {state.kind === 'done' && state.status === 'ok' && (
          <Status ok text={t('server.online', { version: state.info.version })} />
        )}
        {state.kind === 'done' && state.status === 'unsupported_app' && (
          <Status ok={false} text={t('server.unsupported_app')} />
        )}
        {state.kind === 'done' && state.status === 'offline' && <Status ok={false} text={t('server.offline')} />}

        <Pressable
          onPress={onCheck}
          disabled={checking}
          accessibilityState={{ disabled: checking, busy: checking }}
          style={({ pressed }) => [styles.button, (pressed || checking) && { opacity: 0.6 }]}
        >
          <Text style={styles.buttonText}>{t('server.check')}</Text>
        </Pressable>
      </View>
    </View>
  );
}

function Status({ ok, text }: { ok: boolean; text: string }) {
  return (
    <View style={[styles.status, { backgroundColor: ok ? colors['ok-soft'] : colors['danger-soft'] }]}>
      <Text style={{ color: ok ? colors.ok : colors.danger, fontWeight: '500' }}>{text}</Text>
    </View>
  );
}

const styles = StyleSheet.create({
  screen: { flex: 1, backgroundColor: colors.bg, justifyContent: 'center', padding: 16 },
  card: {
    gap: 12,
    padding: 24,
    borderRadius: radius.xl,
    backgroundColor: colors.surface,
    borderWidth: 1,
    borderColor: colors.line2,
  },
  title: { color: colors.text, fontSize: 26, fontWeight: '600' },
  muted: { color: colors.text2, lineHeight: 21 },
  label: { color: colors.text2, fontSize: 13, fontWeight: '500', marginTop: 8 },
  input: {
    height: 48,
    paddingHorizontal: 14,
    borderRadius: radius.md,
    backgroundColor: colors.surface2,
    borderWidth: 1,
    borderColor: colors.line2,
    color: colors.text,
    fontSize: 15,
  },
  status: { flexDirection: 'row', alignItems: 'center', gap: 8, padding: 12, borderRadius: 10 },
  button: {
    height: 48,
    borderRadius: radius.md,
    backgroundColor: colors.accent,
    alignItems: 'center',
    justifyContent: 'center',
  },
  buttonText: { color: '#fff', fontWeight: '600', fontSize: 15 },
});