import { Box, useMediaQuery, useTheme } from "@mui/material";
import { useEffect } from "react";
import Chat from "./Chat/Chat";
import Collapse from "./Collapse";
import TicketList from "./TicketList/TicketList";
import { getTickets, subscribeToAllTickets } from "@root/api/tickets";
import { GetTicketsRequest, Ticket } from "@root/model/ticket";
import { clearTickets, setTicketsFetchState, updateTickets, useTicketStore } from "@root/stores/tickets";
import { enqueueSnackbar } from "notistack";
import { clearMessages } from "@root/stores/messages";
import { authStore } from "@root/stores/auth";

const TICKETS_PER_PAGE = 20;

export default function Support() {
  const theme = useTheme();
  const upMd = useMediaQuery(theme.breakpoints.up("md"));
  const [currentPage, setCurrentPage] = useState<number>(0);
  const { token } = authStore();
  const fetchingStateRef = useRef<"idle" | "fetching" | "all fetched">("idle");

  useEffect(
    function fetchTickets() {
      const getTicketsBody: GetTicketsRequest = {
        amt: TICKETS_PER_PAGE,
        page: currentPage,
        status: "open",
      };
      const controller = new AbortController();

      fetchingStateRef.current = "fetching";
      getTickets({
        body: getTicketsBody,
        signal: controller.signal,
      })
        .then((result) => {
          console.log("GetTicketsResponse", result);
          if (result.data) {
            updateTickets(result.data);
            fetchingStateRef.current = "idle";
          } else fetchingStateRef.current = "all fetched";
        })
        .catch((error) => {
          console.log("Error fetching tickets", error);
          enqueueSnackbar(error.message);
        });

      return () => controller.abort();
    },
    [currentPage]
  );

  useEffect(function subscribeToTickets() {
    if (!token) return;

    const unsubscribe = subscribeToAllTickets({
      accessToken: token,
      onMessage(event) {
        try {
          const newTicket = JSON.parse(event.data) as Ticket;
          console.log("SSE: parsed newTicket:", newTicket);
          updateTickets([newTicket]);
        } catch (error) {
          console.log("SSE: couldn't parse:", event.data);
          console.log("Error parsing ticket SSE", error);
        }
      },
      onError(event) {
        console.log("SSE Error:", event);
      },
    });

    return () => {
      unsubscribe();
      clearMessages();
      clearTickets();
    };
  }, []);

  const incrementCurrentPage = () => setCurrentPage((prev) => prev + 1);

  const ticketList = <TicketList fetchingStateRef={fetchingStateRef} incrementCurrentPage={incrementCurrentPage} />;

  return (
    <Box
      sx={{
        display: "flex",
        width: "100%",
        flexDirection: upMd ? "row" : "column",
        gap: "12px",
      }}
    >
      {!upMd && <Collapse headerText="Тикеты">{ticketList}</Collapse>}
      <Chat />
      {upMd && ticketList}
    </Box>
  );
}