import { Picker } from "@react-native-picker/picker";
import { router } from "expo-router";
import { useEffect, useState } from "react";
import {
  Alert,
  KeyboardAvoidingView,
  Platform,
  Pressable,
  ScrollView,
  StyleSheet,
  Text,
  TextInput,
  View,
} from "react-native";
import { SafeAreaView } from "react-native-safe-area-context";
import {
  loadRecorderSettings,
  saveRecorderSettings,
} from "@/lib/recorder-settings";
import { AVAILABLE_LOCALES, t, type Locale, getStrings } from "@/lib/translations";

function localeLabel(locale: Locale) {
  if (locale === "ca") return "Catal\u00e0";
  if (locale === "en") return "English";
  return locale;
}

export default function SettingsScreen() {
  const [backendUrl, setBackendUrl] = useState("");
  const [authToken, setAuthToken] = useState("");
  const [fieldName, setFieldName] = useState("file");
  const [language, setLanguage] = useState<Locale>("ca");
  const [strings, setStrings] = useState(() => getStrings("ca"));

  useEffect(() => {
    let isMounted = true;

    async function loadSettings() {
      try {
        const settings = await loadRecorderSettings();

        if (!isMounted) {
          return;
        }

        setBackendUrl(settings.backendUrl);
        setAuthToken(settings.authToken);
        setFieldName(settings.fieldName);
        setLanguage(settings.language);
        setStrings(getStrings(settings.language));
      } catch {
        if (isMounted) {
          Alert.alert(strings.loadError, strings.loadError);
        }
      }
    }

    void loadSettings();

    return () => {
      isMounted = false;
    };
  }, []);

  const langStrings = getStrings(language);

  async function handleSave() {
    try {
      await saveRecorderSettings({
        authToken,
        backendUrl,
        fieldName,
        language,
      });
      setStrings(getStrings(language));
      router.back();
    } catch {
      Alert.alert(langStrings.saveError, langStrings.saveError);
    }
  }

  function handleLanguageChange(val: Locale) {
    setLanguage(val);
    setStrings(getStrings(val));
  }

  return (
    <SafeAreaView style={styles.safeArea}>
      <KeyboardAvoidingView
        style={styles.keyboardAvoidingView}
        behavior={Platform.OS === "ios" ? "padding" : undefined}
      >
        <ScrollView
          style={styles.scrollView}
          contentContainerStyle={styles.content}
          keyboardShouldPersistTaps="handled"
        >
          <View style={styles.headerRow}>
            <Pressable onPress={() => router.back()} style={styles.navButton}>
              <Text style={styles.navButtonText}>{langStrings.back}</Text>
            </Pressable>
            <Text style={styles.title}>{langStrings.settingsTitle}</Text>
            <Pressable onPress={handleSave} style={styles.navButton}>
              <Text style={styles.navButtonText}>{langStrings.save}</Text>
            </Pressable>
          </View>

          <View style={styles.panel}>
            <Text style={styles.label}>{langStrings.backendUrl}</Text>
            <TextInput
              autoCapitalize="none"
              autoCorrect={false}
              keyboardType="url"
              onChangeText={setBackendUrl}
              placeholder={langStrings.urlPlaceholder}
              placeholderTextColor="#8f8a7c"
              style={styles.input}
              value={backendUrl}
            />

            <Text style={styles.label}>{langStrings.bearerToken}</Text>
            <TextInput
              autoCapitalize="none"
              autoCorrect={false}
              onChangeText={setAuthToken}
              placeholder={langStrings.tokenOptional}
              placeholderTextColor="#8f8a7c"
              secureTextEntry
              style={styles.input}
              value={authToken}
            />

            <Text style={styles.label}>{langStrings.formFieldName}</Text>
            <TextInput
              autoCapitalize="none"
              autoCorrect={false}
              onChangeText={setFieldName}
              placeholder={langStrings.fieldNamePlaceholder}
              placeholderTextColor="#8f8a7c"
              style={styles.input}
              value={fieldName}
            />

            <Text style={styles.helperText}>
              {t("helperText", language, fieldName.trim() || "file")}
            </Text>
          </View>

          <View style={styles.panel}>
            <Text style={styles.label}>{langStrings.languageTitle}</Text>
            <View style={styles.pickerWrapper}>
              <Picker
                selectedValue={language}
                onValueChange={handleLanguageChange}
                style={styles.picker}
              >
                {AVAILABLE_LOCALES.map((loc) => (
                  <Picker.Item
                    key={loc}
                    label={localeLabel(loc)}
                    value={loc}
                  />
                ))}
              </Picker>
            </View>
          </View>
        </ScrollView>
      </KeyboardAvoidingView>
    </SafeAreaView>
  );
}

const styles = StyleSheet.create({
  safeArea: {
    flex: 1,
    backgroundColor: "#f4efe4",
  },
  keyboardAvoidingView: {
    flex: 1,
  },
  scrollView: {
    flex: 1,
  },
  content: {
    gap: 18,
    paddingHorizontal: 20,
    paddingBottom: 32,
    paddingTop: 8,
  },
  headerRow: {
    alignItems: "center",
    flexDirection: "row",
    justifyContent: "space-between",
  },
  navButton: {
    borderColor: "#cdbfa8",
    borderRadius: 999,
    borderWidth: 1,
    paddingHorizontal: 12,
    paddingVertical: 8,
  },
  navButtonText: {
    color: "#13304a",
    fontSize: 14,
    fontWeight: "700",
  },
  title: {
    color: "#13304a",
    fontSize: 28,
    fontWeight: "800",
  },
  panel: {
    backgroundColor: "#fffaf1",
    borderColor: "#dccfb9",
    borderRadius: 24,
    borderWidth: 1,
    gap: 12,
    padding: 18,
  },
  label: {
    color: "#13304a",
    fontSize: 13,
    fontWeight: "700",
    marginBottom: -4,
    textTransform: "uppercase",
  },
  input: {
    backgroundColor: "#f7f0e0",
    borderColor: "#d9ccb5",
    borderRadius: 16,
    borderWidth: 1,
    color: "#1a2b39",
    fontSize: 16,
    paddingHorizontal: 14,
    paddingVertical: 14,
  },
  helperText: {
    color: "#665f54",
    fontSize: 13,
    lineHeight: 18,
  },
  pickerWrapper: {
    backgroundColor: "#f7f0e0",
    borderColor: "#d9ccb5",
    borderRadius: 16,
    borderWidth: 1,
    overflow: "hidden",
  },
  picker: {
    height: 50,
  },
});