import { Box, IconButton, InputAdornment, TextField, Typography, useMediaQuery, useTheme } from "@mui/material";
import {
	addOrUpdateMessages,
	clearMessageState,
	incrementMessageApiPage,
	setIsPreventAutoscroll,
	setTicketMessagesFetchState,
	useMessageStore,
} from "@root/stores/messages";
import Message from "./Message";
import SendIcon from "@mui/icons-material/Send";
import AttachFileIcon from "@mui/icons-material/AttachFile";
import { KeyboardEvent, useEffect, useMemo, useRef, useState } from "react";
import { useParams } from "react-router-dom";
import { TicketMessage } from "@root/model/ticket";
import { sendTicketMessage } from "@root/api/tickets";
import { enqueueSnackbar } from "notistack";
import { useTicketStore } from "@root/stores/tickets";
import {
	getMessageFromFetchError,
	throttle,
	useEventListener,
	useSSESubscription,
	useTicketMessages,
	useToken,
} from "@frontend/kitui";
import makeRequest from "@root/api/makeRequest";
import ChatImage from "./ChatImage";
import ChatDocument from "./ChatDocument";
import ChatVideo from "./ChatVideo";
import ChatMessage from "./ChatMessage";
import { ACCEPT_SEND_MEDIA_TYPES_MAP, MAX_FILE_SIZE, MAX_PHOTO_SIZE, MAX_VIDEO_SIZE } from "./fileUpload";

const tooLarge = "Файл слишком большой";
const checkAcceptableMediaType = (file: File) => {
	if (file === null) return "";

	const segments = file?.name.split(".");
	const extension = segments[segments.length - 1];
	const type = extension.toLowerCase();

	switch (type) {
		case ACCEPT_SEND_MEDIA_TYPES_MAP.document.find((name) => name === type):
			if (file.size > MAX_FILE_SIZE) return tooLarge;
			return "";

		case ACCEPT_SEND_MEDIA_TYPES_MAP.picture.find((name) => name === type):
			if (file.size > MAX_PHOTO_SIZE) return tooLarge;
			return "";

		case ACCEPT_SEND_MEDIA_TYPES_MAP.video.find((name) => name === type):
			if (file.size > MAX_VIDEO_SIZE) return tooLarge;
			return "";

		default:
			return "Не удалось отправить файл. Недопустимый тип";
	}
};

export default function Chat() {
	const token = useToken();
	const theme = useTheme();
	const upMd = useMediaQuery(theme.breakpoints.up("md"));
	const tickets = useTicketStore((state) => state.tickets);
	const messages = useMessageStore((state) => state.messages);
	const [messageField, setMessageField] = useState<string>("");
	const ticketId = useParams().ticketId;
	const chatBoxRef = useRef<HTMLDivElement>(null);
	const messageApiPage = useMessageStore((state) => state.apiPage);
	const messagesPerPage = useMessageStore((state) => state.messagesPerPage);
	const isPreventAutoscroll = useMessageStore((state) => state.isPreventAutoscroll);
	const fetchState = useMessageStore((state) => state.ticketMessagesFetchState);
	const lastMessageId = useMessageStore((state) => state.lastMessageId);
	const fileInputRef = useRef<HTMLInputElement>(null);
	const [disableFileButton, setDisableFileButton] = useState(false);

	const ticket = tickets.find((ticket) => ticket.id === ticketId);

	useTicketMessages({
		url: process.env.REACT_APP_DOMAIN + "/heruvym/getMessages",
		ticketId,
		messagesPerPage,
		messageApiPage,
		onSuccess: (messages) => {
			if (chatBoxRef.current && chatBoxRef.current.scrollTop < 1) chatBoxRef.current.scrollTop = 1;
			addOrUpdateMessages(messages);
		},
		onError: (error: Error) => {
			const message = getMessageFromFetchError(error);
			if (message) enqueueSnackbar(message);
		},
		onFetchStateChange: setTicketMessagesFetchState,
	});

	useSSESubscription<TicketMessage>({
		enabled: Boolean(token) && Boolean(ticketId),
		url: process.env.REACT_APP_DOMAIN + `/heruvym/ticket?ticket=${ticketId}&Authorization=${token}`,
		onNewData: addOrUpdateMessages,
		onDisconnect: () => {
			clearMessageState();
			setIsPreventAutoscroll(false);
		},
		marker: "ticket message",
	});

	const throttledScrollHandler = useMemo(
		() =>
			throttle(() => {
				const chatBox = chatBoxRef.current;
				if (!chatBox) return;

				const scrollBottom = chatBox.scrollHeight - chatBox.scrollTop - chatBox.clientHeight;
				const isPreventAutoscroll = scrollBottom > chatBox.clientHeight * 20;
				setIsPreventAutoscroll(isPreventAutoscroll);

				if (fetchState !== "idle") return;

				if (chatBox.scrollTop < chatBox.clientHeight) {
					incrementMessageApiPage();
				}
			}, 200),
		[fetchState]
	);

	useEventListener("scroll", throttledScrollHandler, chatBoxRef);

	useEffect(
		function scrollOnNewMessage() {
			if (!chatBoxRef.current) return;

			if (!isPreventAutoscroll) {
				setTimeout(() => {
					scrollToBottom();
				}, 50);
			}
			// eslint-disable-next-line react-hooks/exhaustive-deps
		},
		[lastMessageId]
	);

	function scrollToBottom(behavior?: ScrollBehavior) {
		if (!chatBoxRef.current) return;

		const chatBox = chatBoxRef.current;
		chatBox.scroll({
			left: 0,
			top: chatBox.scrollHeight,
			behavior,
		});
	}

	function handleSendMessage() {
		if (!ticket || !messageField) return;

		sendTicketMessage({
			files: [],
			lang: "ru",
			message: messageField,
			ticket: ticket.id,
		});
		setMessageField("");
	}

	const sendFile = async (file: File) => {
		if (file === undefined) return true;

		let data;

		const ticketId = ticket?.id;
		if (ticketId !== undefined) {
			try {
				const body = new FormData();

				body.append(file.name, file);
				body.append("ticket", ticketId);
				await makeRequest({
					url: process.env.REACT_APP_DOMAIN + "/heruvym/sendFiles",
					body: body,
					method: "POST",
				});
			} catch (error: any) {
				const errorMessage = getMessageFromFetchError(error);
				if (errorMessage) enqueueSnackbar(errorMessage);
			}
			return true;
		}
	};
	const sendFileHC = async (file: File) => {
		const check = checkAcceptableMediaType(file);
		if (check.length > 0) {
			enqueueSnackbar(check);
			return;
		}
		setDisableFileButton(true);
		await sendFile(file);
		setDisableFileButton(false);
	};

	function handleTextfieldKeyPress(e: KeyboardEvent) {
		if (e.key === "Enter" && !e.shiftKey) {
			e.preventDefault();
			handleSendMessage();
		}
	}

	return (
		<Box
			sx={{
				border: "1px solid",
				borderColor: theme.palette.grayDark.main,
				height: "600px",
				borderRadius: "3px",
				p: "8px",
				display: "flex",
				flex: upMd ? "2 0 0" : undefined,
				flexDirection: "column",
				justifyContent: "center",
				alignItems: "center",
				gap: "8px",
			}}
		>
			<Typography>{ticket ? ticket.title : "Выберите тикет"}</Typography>
			<Box
				ref={chatBoxRef}
				sx={{
					width: "100%",
					backgroundColor: "#46474a",
					flexGrow: 1,
					display: "flex",
					flexDirection: "column",
					gap: "12px",
					p: "8px",
					overflow: "auto",
					colorScheme: "dark",
				}}
			>
				{ticket &&
					messages.map((message) => {
						const isFileVideo = () => {
							if (message.files) {
								return ACCEPT_SEND_MEDIA_TYPES_MAP.video.some((fileType) =>
									message.files[0].toLowerCase().endsWith(fileType)
								);
							}
						};
						const isFileImage = () => {
							if (message.files) {
								return ACCEPT_SEND_MEDIA_TYPES_MAP.picture.some((fileType) =>
									message.files[0].toLowerCase().endsWith(fileType)
								);
							}
						};
						const isFileDocument = () => {
							if (message.files) {
								return ACCEPT_SEND_MEDIA_TYPES_MAP.document.some((fileType) =>
									message.files[0].toLowerCase().endsWith(fileType)
								);
							}
						};
						if (message.files !== null && message.files.length > 0 && isFileImage()) {
							return (
								<ChatImage
									unAuthenticated
									key={message.id}
									file={message.files[0]}
									createdAt={message.created_at}
									isSelf={ticket.user !== message.user_id}
								/>
							);
						}
						if (message.files !== null && message.files.length > 0 && isFileVideo()) {
							return (
								<ChatVideo
									unAuthenticated
									key={message.id}
									file={message.files[0]}
									createdAt={message.created_at}
									isSelf={ticket.user !== message.user_id}
								/>
							);
						}
						if (message.files !== null && message.files.length > 0 && isFileDocument()) {
							return (
								<ChatDocument
									unAuthenticated
									key={message.id}
									file={message.files[0]}
									createdAt={message.created_at}
									isSelf={ticket.user !== message.user_id}
								/>
							);
						}
						return (
							<ChatMessage
								unAuthenticated
								key={message.id}
								text={message.message}
								createdAt={message.created_at}
								isSelf={ticket.user !== message.user_id}
							/>
						);
					})}
			</Box>
			{ticket && (
				<TextField
					value={messageField}
					onChange={(e) => setMessageField(e.target.value)}
					onKeyPress={handleTextfieldKeyPress}
					id="message-input"
					placeholder="Написать сообщение"
					fullWidth
					multiline
					maxRows={8}
					InputProps={{
						style: {
							backgroundColor: theme.palette.content.main,
							color: theme.palette.secondary.main,
						},
						endAdornment: (
							<InputAdornment position="end">
								<IconButton
									onClick={handleSendMessage}
									sx={{
										height: "45px",
										width: "45px",
										p: 0,
									}}
								>
									<SendIcon sx={{ color: theme.palette.golden.main }} />
								</IconButton>
								<IconButton
									onClick={() => {
										if (!disableFileButton) fileInputRef.current?.click();
									}}
									sx={{
										height: "45px",
										width: "45px",
										p: 0,
									}}
								>
									<input
										ref={fileInputRef}
										id="fileinput"
										onChange={(e) => {
											if (e.target.files?.[0]) sendFileHC(e.target.files?.[0]);
										}}
										style={{ display: "none" }}
										type="file"
									/>
									<AttachFileIcon sx={{ color: theme.palette.golden.main }} />
								</IconButton>
							</InputAdornment>
						),
					}}
					InputLabelProps={{
						style: {
							color: theme.palette.secondary.main,
						},
					}}
				/>
			)}
		</Box>
	);
}