import ReturnArrow from "@/assets/icons/svg/returnArrow.svg";
import Chat from "@/components/ask/chat";
import AskHello from "@/components/ask/hello";
import SendMessage from "@/components/ask/send";
import { ThemedText } from "@/components/ThemedText";
import { useWebSocketStreamHandler } from "@/hooks/useWebSocketStreamHandler";
import { fetchApi } from "@/lib/server-api-util";
import { Message } from "@/types/ask";
import { useFocusEffect, useLocalSearchParams, useRouter } from "expo-router";
import { useCallback, useEffect, useRef, useState } from 'react';
import { useTranslation } from "react-i18next";
import {
    Animated,
    FlatList,
    Keyboard,
    KeyboardAvoidingView,
    Platform,
    StyleSheet,
    TextInput,
    TouchableOpacity,
    View
} from 'react-native';
import { useAnimatedStyle, useSharedValue, withTiming } from 'react-native-reanimated';
import { useSafeAreaInsets } from "react-native-safe-area-context";

export default function AskScreen() {
    const router = useRouter();
    const insets = useSafeAreaInsets();

    const chatListRef = useRef<FlatList>(null);
    const isMountedRef = useRef(true);
    const scrollTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null);
    const keyboardTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null);
    const abortControllerRef = useRef<AbortController | null>(null);

    const [isHello, setIsHello] = useState(true);
    const [conversationId, setConversationId] = useState<string | null>(null);
    const [userMessages, setUserMessages] = useState<Message[]>([]);
    const [selectedImages, setSelectedImages] = useState<string[]>([]);
    const fadeAnim = useSharedValue(1);
    const fadeAnimChat = useSharedValue(0);
    const { t } = useTranslation();

    const { sessionId, newSession } = useLocalSearchParams<{
        sessionId: string;
        newSession: string;
    }>();

    // 创建一个安全的滚动函数
    const scrollToEnd = useCallback((animated = true) => {
        if (!isMountedRef.current || !chatListRef.current) return;

        // 清理之前的定时器
        if (scrollTimeoutRef.current) {
            clearTimeout(scrollTimeoutRef.current);
        }

        scrollTimeoutRef.current = setTimeout(() => {
            if (isMountedRef.current && chatListRef.current) {
                try {
                    chatListRef.current.scrollToEnd({ animated });
                } catch (error) {
                    console.warn('滚动到底部失败:', error);
                }
            }
        }, 100);
    }, []);

    // 清理函数
    const cleanup = useCallback(() => {
        isMountedRef.current = false;

        // 清理定时器
        if (scrollTimeoutRef.current) {
            clearTimeout(scrollTimeoutRef.current);
            scrollTimeoutRef.current = null;
        }
        if (keyboardTimeoutRef.current) {
            clearTimeout(keyboardTimeoutRef.current);
            keyboardTimeoutRef.current = null;
        }

        // 取消API请求
        if (abortControllerRef.current) {
            abortControllerRef.current.abort();
            abortControllerRef.current = null;
        }
    }, []);

    // 暂时注释掉复杂的useEffect逻辑
    // useEffect(() => {
    //     if (!isHello && userMessages.length > 0 && isMountedRef.current) {
    //         scrollToEnd();
    //     }
    // }, [userMessages, isHello, scrollToEnd]);

    // useEffect(() => {
    //     const keyboardDidShowListener = Keyboard.addListener(
    //         'keyboardDidShow',
    //         (e) => {
    //             if (keyboardTimeoutRef.current) {
    //                 clearTimeout(keyboardTimeoutRef.current);
    //             }
    //             keyboardTimeoutRef.current = setTimeout(() => {
    //                 if (isMountedRef.current && !isHello) {
    //                     scrollToEnd();
    //                 }
    //             }, 100);
    //         }
    //     );
    //     const keyboardDidHideListener = Keyboard.addListener(
    //         'keyboardDidHide',
    //         () => {
    //             if (keyboardTimeoutRef.current) {
    //                 clearTimeout(keyboardTimeoutRef.current);
    //             }
    //             keyboardTimeoutRef.current = setTimeout(() => {
    //                 if (isMountedRef.current && !isHello) {
    //                     scrollToEnd(false);
    //                 }
    //             }, 100);
    //         }
    //     );
    //     return () => {
    //         keyboardDidShowListener.remove();
    //         keyboardDidHideListener.remove();
    //         if (keyboardTimeoutRef.current) {
    //             clearTimeout(keyboardTimeoutRef.current);
    //         }
    //     };
    // }, [isHello, scrollToEnd]);

    // 暂时注释掉WebSocket hook来排查问题
    // const { subscribeToWebSocket } = useWebSocketStreamHandler({
    //     setUserMessages,
    //     isMounted: true,
    //     enableBatching: false
    // });

    // useFocusEffect(
    //     useCallback(() => {
    //         isMountedRef.current = true;
    //         const unsubscribe = subscribeToWebSocket();
    //         return () => {
    //             unsubscribe();
    //             cleanup();
    //         };
    //     }, [subscribeToWebSocket, cleanup])
    // );

    // 创建动画样式
    const welcomeStyle = useAnimatedStyle(() => {
        return {
            opacity: fadeAnim.value,
            pointerEvents: isHello ? 'auto' : 'none',
        };
    });

    const chatStyle = useAnimatedStyle(() => {
        return {
            opacity: fadeAnimChat.value,
            pointerEvents: isHello ? 'none' : 'auto',
        };
    });

    // 暂时注释掉所有复杂的useEffect逻辑
    // useEffect(() => {
    //     fadeAnim.value = withTiming(isHello ? 1 : 0, { duration: 300 });
    //     fadeAnimChat.value = withTiming(isHello ? 0 : 1, { duration: 300 });
    // }, [isHello]);

    // useEffect(() => {
    //     if (sessionId && isMountedRef.current) {
    //         setConversationId(sessionId);
    //         setIsHello(false);
    //         abortControllerRef.current = new AbortController();
    //         fetchApi<Message[]>(`/chats/${sessionId}/message-history`, {
    //             signal: abortControllerRef.current.signal
    //         }).then((res) => {
    //             if (isMountedRef.current) {
    //                 setUserMessages(res);
    //             }
    //         }).catch((error) => {
    //             if (error.name !== 'AbortError') {
    //                 console.error('获取消息历史失败:', error);
    //             }
    //         });
    //     }
    //     if (newSession && isMountedRef.current) {
    //         setIsHello(true);
    //         setConversationId(null);
    //     }
    // }, [sessionId, newSession]);

    // useEffect(() => {
    //     if (!isHello && isMountedRef.current) {
    //         scrollToEnd(false);
    //     }
    // }, [isHello, scrollToEnd]);

    // useFocusEffect(
    //     useCallback(() => {
    //         if (!sessionId && isMountedRef.current) {
    //             setIsHello(true);
    //             setUserMessages([]);
    //         }
    //     }, [sessionId])
    // );
    
    // useEffect(() => {
    //     return () => {
    //         cleanup();
    //     };
    // }, [cleanup]);

    return (
        <View style={[styles.container, { paddingTop: insets.top, paddingBottom: insets.bottom }]}>
            {/* 导航栏 */}
            <View style={[styles.navbar, isHello && styles.hiddenNavbar]}>
                <TouchableOpacity
                    style={styles.backButton}
                    onPress={() => {
                        try {
                            if (TextInput.State?.currentlyFocusedInput) {
                                const input = TextInput.State.currentlyFocusedInput();
                                if (input) input.blur();
                            }
                        } catch (error) {
                            console.log('失去焦点失败:', error);
                        }
                        Keyboard.dismiss();
                        router.push('/memo-list');
                    }}
                >
                    <ReturnArrow />
                </TouchableOpacity>
                <ThemedText style={styles.title} onPress={() => { router.push('/owner') }}>MemoWake</ThemedText>
                <View style={styles.placeholder} />
            </View>

            <View style={styles.contentContainer}>
                {/* 欢迎页面 */}
                <Animated.View
                    style={[styles.absoluteView, welcomeStyle, { zIndex: 1 }]}
                >
                    <AskHello setUserMessages={setUserMessages} setConversationId={setConversationId} setIsHello={setIsHello} />
                </Animated.View>

                {/* 聊天页面 */}
                <Animated.View
                    style={[styles.absoluteView, chatStyle, { zIndex: 0 }]}
                >
                    <Chat
                        ref={chatListRef}
                        userMessages={userMessages}
                        sessionId={sessionId}
                        setSelectedImages={setSelectedImages}
                        selectedImages={selectedImages}
                        style={styles.chatContainer}
                        contentContainerStyle={styles.chatContentContainer}
                        showsVerticalScrollIndicator={false}
                    // onContentSizeChange={() => scrollToEnd()}
                    />
                </Animated.View>
            </View>

            {/* 输入框区域 */}
            <KeyboardAvoidingView
                behavior={Platform.OS === "ios" ? "padding" : "height"}
                keyboardVerticalOffset={0} >
                <View style={styles.inputContainer} key={conversationId}>
                    <SendMessage
                        setIsHello={setIsHello}
                        conversationId={conversationId}
                        setConversationId={setConversationId}
                        setUserMessages={setUserMessages}
                        selectedImages={selectedImages}
                        setSelectedImages={setSelectedImages}
                    />
                </View>
            </KeyboardAvoidingView>
        </View>
    );
}

const styles = StyleSheet.create({
    container: {
        flex: 1,
        backgroundColor: '#fff',
    },
    navbar: {
        flexDirection: 'row',
        alignItems: 'center',
        justifyContent: 'space-between',
        paddingVertical: 16,
        paddingHorizontal: 16,
        borderBottomWidth: 1,
        borderBottomColor: 'rgba(0,0,0,0.1)',
        elevation: 1, // Android
        shadowColor: '#000',
        shadowOffset: { width: 0, height: 1 },
        shadowOpacity: 0.1,
        shadowRadius: 1,
    },
    hiddenNavbar: {
        shadowOpacity: 0,
        elevation: 0,
        opacity: 0
    },
    backButton: {
        padding: 8,
        marginRight: 8,
    },
    title: {
        fontSize: 20,
        fontWeight: '600',
        textAlign: 'center',
        flex: 1,
    },
    placeholder: {
        width: 40,
    },
    contentContainer: {
        flex: 1,
        position: 'relative'
    },
    absoluteView: {
        position: 'absolute',
        top: 0,
        left: 0,
        right: 0,
        bottom: 0,
        backgroundColor: 'white',
    },
    chatContainer: {
        flex: 1,
    },
    chatContentContainer: {
        paddingBottom: 20,
    },
    inputContainer: {
        padding: 16,
        paddingBottom: 24,
        backgroundColor: 'white',
        // borderTopWidth: 1,
        // borderTopColor: '#f0f0f0',
    },
});