import React, {useEffect, useState} from 'react';
import {StyleSheet, ActivityIndicator, SafeAreaView, View, Platform, KeyboardAvoidingView} from 'react-native';
import {useAuthStore} from '@/store/authStore';
import {useRouter} from 'expo-router';

import {Box} from "@/components/ui/box"
import {Button, ButtonText, ButtonIcon} from "@/components/ui/button"
import {Center} from "@/components/ui/center"
import {Heading} from "@/components/ui/heading"
import {Input, InputField, InputIcon, InputSlot} from "@/components/ui/input"
import {Text} from "@/components/ui/text"
import {VStack} from "@/components/ui/vstack"
import {HStack} from "@/components/ui/hstack"
import {ArrowRightIcon, EyeIcon, EyeOffIcon} from "@/components/ui/icon"
import {Divider} from '@/components/ui/divider';
import {Ionicons} from "@expo/vector-icons";

import * as WebBrowser from 'expo-web-browser';
import * as Google from "expo-auth-session/providers/google";
import AsyncStorage from "@react-native-async-storage/async-storage";
import {makeRedirectUri} from "expo-auth-session";

import Constants from 'expo-constants';

WebBrowser.maybeCompleteAuthSession();

// client_id ios 936418008320-ohefdfcebd41f6oa2o8phh1mgj9s49sl.apps.googleusercontent.com
// android 936418008320-d8dfjph5e4r28fcm1rbdfbh5phmbg03d.apps.googleusercontent.com

export default function Login() {
    const [email, setEmail] = useState('');
    const [password, setPassword] = useState('');
    const [emailError, setEmailError] = useState('');
    const [showPassword, setShowPassword] = useState(false)
    const {signIn, isLoading, signInWithGoogle} = useAuthStore();
    const router = useRouter();

    const [request, response, promptAsync] = Google.useAuthRequest({
        androidClientId: "936418008320-d8dfjph5e4r28fcm1rbdfbh5phmbg03d.apps.googleusercontent.com",
        iosClientId: "936418008320-ohefdfcebd41f6oa2o8phh1mgj9s49sl.apps.googleusercontent.com",
        webClientId: "936418008320-btdngtlfnjac1p67guje72m9el5q59a7.apps.googleusercontent.com",
        redirectUri:
            Platform.OS === 'android'
                ? makeRedirectUri({
                    scheme: Constants.expoConfig.android.package,
                    path: '/',
                })
                : undefined,
    })

    const handleInternalLogin = async () => {
        if (!email || !password) {
            alert('Proszę wprowadzić email i hasło.');
            return;
        }

        if (!validateEmail(email)) {
            setEmailError('Nieprawidłowy format adresu email');
            return;
        }

        try {
            await signIn(email, password);
            alert(`Zalogowano jako ${email}`);
            router.replace('/');
        } catch (e) {
            alert("Błąd logowania: " + (e.response?.data?.message || e.message));
        }
    }

    useEffect(() => {
        handleGoogleLogin();
    }, [response]);

    const handleGoogleLogin = async () => {
        // const user = await AsyncStorage.getItem("@user");
        let user = null;
        if (!user) {
            if (response.type === "success") {
                user = await getUserInfo(response.authentication.accessToken)
                await signInWithGoogle(response.authentication.accessToken);
                alert(`Zalogowano jako ${user.email}`);
                router.replace('/');
            }

        } else {
            console.info("Pobrano użytkownika z AsyncStorage:", JSON.parse(user));
            alert(`Zalogowano jako ${user.email}`);
        }
    };

    const getUserInfo = async (token) => {
        if (!token) {
            return
        }
        try {
            const response = await fetch("https://www.googleapis.com/userinfo/v2/me",
                {
                    headers: {
                        Authorization: `Bearer ${token}`
                    },
                }
            );
            const user = await response.json();
            await AsyncStorage.setItem("@user", JSON.stringify(user));
            return user;
        } catch (error) {
            console.error("Błąd podczas pobierania informacji o użytkowniku:", error);
            throw error;
        }
    }

    const validateEmail = (email) => {
        const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
        return emailRegex.test(email);
    };

    const handleShowPassword = () => {
        setShowPassword((showState) => {
            return !showState
        })
    }

    if (isLoading) {
        return (
            <View style={styles.container}>
                <ActivityIndicator size="large"/>
            </View>
        );
    }

    return (
        <KeyboardAvoidingView
            behavior={Platform.OS === "ios" ? "padding" : "height"}
            style={{flex: 1}}
            keyboardVerticalOffset={Platform.OS === "ios" ? 64 : 0}
        >
            <SafeAreaView style={styles.container}>
                <Center>
                    <Box className="p-5 max-w-96 border border-background-300 rounded-lg">
                        <VStack className="pb-4" space="xs">
                            <Heading className="leading-[30px]">Logowanie</Heading>
                            <Box className="flex flex-row">
                                {/* <Link href="/registration" asChild> */}
                                <Button variant="link" size="sm" className="p-0"
                                        onPress={() => router.replace("/registration")}>
                                    <ButtonText style={styles.signupbutton}>Nie masz jeszcze konta? Załóz je
                                        tutaj!</ButtonText>
                                    <ButtonIcon className="mr-1" size="md" as={ArrowRightIcon}/>
                                </Button>
                                {/* </Link> */}
                            </Box>
                        </VStack>
                        <VStack space="xl" className="py-2">
                            {emailError ? <Text style={styles.errorText}>{emailError}</Text> : null}
                            <Input isRequired={true} isInvalid={!!emailError}>
                                <InputField className="py-2" inputMode="email" placeholder="Login"
                                            onChangeText={(text) => {
                                                setEmail(text);
                                                if (text && !validateEmail(text)) {
                                                    setEmailError('Nieprawidłowy format adresu email');
                                                } else {
                                                    setEmailError('');
                                                }
                                            }}
                                />
                            </Input>
                            <Input isRequired={true}>
                                <InputField type={showPassword ? "text" : "password"} className="py-2"
                                            placeholder="Hasło"
                                            onChangeText={setPassword}/>
                                <InputSlot className="pr-3" onPress={handleShowPassword}>
                                    <InputIcon as={showPassword ? EyeIcon : EyeOffIcon}/>
                                </InputSlot>
                            </Input>
                        </VStack>
                        <VStack space="lg" className="pt-4">
                            <Button size="sm" onPress={handleInternalLogin}>
                                <ButtonText>Zaloguj się</ButtonText>
                            </Button>
                        </VStack>

                        <HStack alignItems="center" space="sm" className="pt-6 pb-6">
                            <Divider flex={1}/>
                            <Text fontSize="$sm" className="text-gray-300">
                                lub
                            </Text>
                            <Divider flex={1}/>
                        </HStack>
                        <Button size="sm" onPress={() => promptAsync()}>
                            <Ionicons name="logo-google" color="#fff"/>
                        </Button>
                    </Box>
                </Center>
            </SafeAreaView>
        </KeyboardAvoidingView>
    );
}

const styles = StyleSheet.create({
    container: {
        flex: 1,
        justifyContent: 'center',
        padding: 20,
    },
    input: {
        borderWidth: 1,
        borderColor: '#ddd',
        borderRadius: 5,
        marginBottom: 15,
        padding: 10,
    },
    errorText: {
        color: 'red',
        fontSize: 12,
    },
    signupbutton: {
        fontWeight: '300',
    },
});