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 { fetchApi } from "@/lib/server-api-util";
import { Message } from "@/types/ask";
import { router, useLocalSearchParams } from "expo-router";
import { useCallback, useEffect, useRef, useState } from 'react';
import { KeyboardAvoidingView, Platform, ScrollView, StyleSheet, TouchableOpacity, View } from 'react-native';
import { useSafeAreaInsets } from "react-native-safe-area-context";

export default function AskScreen() {
    const insets = useSafeAreaInsets();
    // 在组件内部添加 ref
    const scrollViewRef = useRef<ScrollView>(null);
    // 用于控制是否显示问候页面
    const [isHello, setIsHello] = useState(true);

    // 获取对话id
    const [conversationId, setConversationId] = useState<string | null>(null);

    // 用户对话信息收集
    const [userMessages, setUserMessages] = useState<Message[]>([]);

    const createNewConversation = useCallback(async () => {
        // TODO 用户未输入时，显示提示信息
        setUserMessages([{
            content: {
                text: "请输入您的问题，寻找，请稍等..."
            },
            role: 'Assistant',
            timestamp: new Date().toISOString()
        }]);
        const data = await fetchApi<string>("/chat/new", {
            method: "POST",
        });
        setConversationId(data);
    }, []);

    // 获取路由参数
    const { sessionId, newSession } = useLocalSearchParams<{
        sessionId: string;
        newSession: string;
    }>();
    // 添加自动滚动到底部的效果
    useEffect(() => {
        if (scrollViewRef.current && !isHello) {
            scrollViewRef.current.scrollToEnd({ animated: true });
        }
    }, [userMessages, isHello]);

    useEffect(() => {
        if (sessionId) {
            setConversationId(sessionId)
            setIsHello(false)
            fetchApi<Message[]>(`/chats/${sessionId}/message-history`).then((res) => {
                setUserMessages(res)
            })
        }
        if (newSession) {
            setIsHello(false)
            createNewConversation()
        }
    }, [sessionId, newSession])

    return (
        <View style={{ flex: 1, backgroundColor: 'white', paddingTop: insets.top }}>
            {/* 导航栏 - 保持在顶部 */}
            <View style={isHello ? "" : styles.navbar} className="relative w-full flex flex-row items-center justify-between pb-3 pt-[2rem]">
                {/* 点击去memo list 页面 */}
                <TouchableOpacity
                    style={styles.backButton}
                    onPress={() => {
                        router.replace('/memo-list');
                    }}
                >
                    <ReturnArrow />
                </TouchableOpacity>
                <ThemedText className={`!text-textSecondary font-semibold text-3xl w-full text-center flex-1 ${isHello ? "opacity-0" : ""}`}>MemoWake</ThemedText>
                <View />
            </View>

            <KeyboardAvoidingView
                style={{ flex: 1 }}
                behavior={Platform.OS === "ios" ? "padding" : "height"}
                keyboardVerticalOffset={Platform.OS === "ios" ? 0 : 20}
            >
                <ScrollView
                    ref={scrollViewRef}
                    contentContainerStyle={{ flexGrow: 1 }}
                    keyboardShouldPersistTaps="handled"
                    showsVerticalScrollIndicator={false}
                    bounces={false}
                    onContentSizeChange={() => {
                        if (scrollViewRef.current && !isHello) {
                            scrollViewRef.current.scrollToEnd({ animated: true });
                        }
                    }}
                >
                    {/* 内容区域 */}
                    <View className="flex-1">
                        {isHello ? <AskHello /> : <Chat userMessages={userMessages} sessionId={sessionId} />}
                    </View>
                </ScrollView>

                {/* 功能区 - 放在 KeyboardAvoidingView 内但在 ScrollView 外 */}
                <View className="w-full px-[1.5rem] mb-[2rem]">
                    <SendMessage setUserMessages={setUserMessages} setConversationId={setConversationId} setIsHello={setIsHello} conversationId={conversationId} />
                </View>
            </KeyboardAvoidingView>
        </View>
    );
}

const styles = StyleSheet.create({
    navbar: {
        boxShadow: '0 4px 6px -1px rgba(0, 0, 0, 0.1)',
        backgroundColor: 'white',
        zIndex: 10,
    },
    container: {
        flex: 1,
        backgroundColor: 'white',
        borderTopLeftRadius: 20,
        borderTopRightRadius: 20,
        paddingTop: 60
    },
    backButton: {
        marginLeft: 16,
        padding: 12
    },
    content: {
        flex: 1,
        padding: 20,
        alignItems: 'center',
        justifyContent: 'center',
    },
    description: {
        fontSize: 16,
        color: '#666',
        textAlign: 'center',
        marginBottom: 40,
        paddingHorizontal: 20,
        lineHeight: 24,
    },
    chipsContainer: {
        width: "100%",
        flexDirection: 'row',
        flexWrap: 'nowrap',
        justifyContent: 'center',
        marginBottom: 40,
        display: "flex",
        alignItems: "center",
        overflow: "scroll",
    },
    chip: {
        flexDirection: 'row',
        alignItems: 'center',
        backgroundColor: '#FFF5E6',
        paddingVertical: 10,
        paddingHorizontal: 16,
        borderRadius: 20,
        margin: 5,
    },
    chipText: {
        marginLeft: 6,
        color: '#FF9500',
        fontSize: 14,
    },
    inputContainer: {
        flexDirection: 'row',
        padding: 16,
        paddingBottom: 30,
        backgroundColor: 'white',
    },
    input: {
        flex: 1,
        borderColor: '#FF9500',
        borderWidth: 1,
        borderRadius: 25,
        paddingHorizontal: 20,
        paddingVertical: 12,
        fontSize: 16,
        width: '100%', // 确保输入框宽度撑满
    },
    voiceButton: {
        width: 40,
        height: 40,
        borderRadius: 20,
        backgroundColor: '#FF9500',
        justifyContent: 'center',
        alignItems: 'center',
        marginRight: 8, // 添加一点右边距
    },
});