import Viewer from "miew-react";
import Miew from "miew";
import {
  Paper,
  UnstyledButton,
  useMantineColorScheme,
  useMantineTheme,
} from "@mantine/core";
import { useEffect, useMemo, useRef, useState } from "react";
import "./MoleculeViewer.css";
import { notifications } from "@mantine/notifications";
import {
  IconAlertHexagon,
  IconArrowBarBoth,
  IconRefresh,
} from "@tabler/icons-react";
import MoleculeViewerMenu from "./MoleculeViewerMenu";
import type { SelectedAtom } from "Types/Experiment/MoleculeEdit/MoleculeEdit";

const callbackOnResizeFinish = (
  dom_elem: HTMLElement,
  beginning_callback: () => void,
  end_callback: () => void,
  delay = 100, // ms after resize "finishes"
) => {
  let timeoutId: number | undefined;

  const resizeObserver = new ResizeObserver(() => {
    beginning_callback();
    if (timeoutId) {
      window.clearTimeout(timeoutId);
    }

    timeoutId = window.setTimeout(() => {
      end_callback();
    }, delay);
  });

  resizeObserver.observe(dom_elem);

  return () => resizeObserver.disconnect(); // cleanup helper
};

interface MoleculeViewerProps {
  moleculeData: string;
  selectedAtom: SelectedAtom | null;
  setSelectedAtom: (selectedAtom: SelectedAtom | null) => void;
}

function MoleculeViewer(props: MoleculeViewerProps) {
  const theme = useMantineTheme();
  const { colorScheme } = useMantineColorScheme();
  // объект загруженного редактора молекул для редактирования
  const [miew, setMiew] = useState<Miew | null>(null);
  const molViewerRef = useRef<HTMLDivElement>(null);

  const [isResizing, setIsResizing] = useState<boolean>(false);

  const [viewingData, setViewingData] = useState<string>(props.moleculeData);

  //при загрузке сохраняем объект miew
  const onInitMiew = (miew: Miew) => {
    setMiew(miew);
    if (miew && viewingData) {
      //прогружаем молекулу
      miew
        .load(viewingData, {
          sourceType: "immediate",
          fileType: "xyz",
        })
        .then(() => {
          if (props.selectedAtom) {
            props.setSelectedAtom(null);
          }
        })
        .catch((error) => {
          if (error.message == "Operation cancelled") {
            return;
          }
          notifications.show({
            color: "orange",
            radius: "md",
            title: "Ошибка при отображении молекулы",
            message:
              "Проверте правильность написания кода молекулы, в нем содержатся ошибки",
            icon: <IconAlertHexagon />,
            style: { paddingLeft: "5px" },
          });
        });
    }
    miew.setOptions({
      settings: {
        bg: {
          color: theme.colors.secondaryDark[7],
        },
        fogAlpha: 0.7,
        axes: true,
      },
    });
  };

  //мемоизируем объект чтобы он не перегружаля при изменении [miew] состояния
  const MemoViewer = useMemo(
    () => <Viewer onInit={onInitMiew} />,
    [viewingData],
  );

  //Замена станартного обработчика нажатия на молекулы
  useEffect(() => {
    if (molViewerRef.current && miew) {
      //INFO: при изменении размера окна обносить webgl
      const cleanup = callbackOnResizeFinish(
        molViewerRef.current,
        handleResizeStart,
        handleResizeEnd,
      );
      //@ts-expect-error Miew class not implementing typescript correctly
      miew.removeEventListener("newpick");
      //@ts-expect-error Miew class not implementing typescript correctly
      miew.addEventListener("newpick", handleClick);
      return () => {
        cleanup();
        //@ts-expect-error Miew class not implementing typescript correctly
        miew.removeEventListener("newpick");
      };
    }
  }, [molViewerRef, miew]);

  //On selected Atom change, highlight it
  useEffect(() => {
    if (miew) {
      if (!props.selectedAtom) {
        //@ts-expect-error Miew class not implementing typescript correctly
        miew.select("");
        return;
      }
      //@ts-expect-error Miew class not implementing typescript correctly
      miew.select("serial  " + props.selectedAtom.serial, false);
      //спрятать информацию встроенную
      //@ts-expect-error Miew class not implementing typescript correctly
      miew._msgAtomInfo.style.opacity = 0.0;
      //@ts-expect-error Miew class not implementing typescript correctly
      miew._msgAtomInfo.style.height = "0px";
      //@ts-expect-error Miew class not implementing typescript correctly
      miew._msgAtomInfo.style.overflow = "hidden";
    }
  }, [props.selectedAtom, miew]);

  //при смене темы обновляем фон MoleculeViewer
  useEffect(() => {
    if (miew) {
      miew.setOptions({
        settings: {
          bg: {
            color: theme.colors.secondaryDark[7],
          },
        },
      });
    }
  }, [colorScheme]);

  //при нажятии на атом выбираем его
  const handleClick = (pick: { type: string; obj: { atom: SelectedAtom } }) => {
    if (miew) {
      if (pick.obj.atom) {
        props.setSelectedAtom(pick.obj.atom);
      } else {
        props.setSelectedAtom(null);
      }
    }
  };

  const handleResizeStart = () => {
    setIsResizing(true);
  };

  const handleResizeEnd = () => {
    //@ts-expect-error Miew class not implementing typescript correctly
    miew._onResize();
    //@ts-expect-error Miew class not implementing typescript correctly
    miew._picker.handleResize();
    setTimeout(() => {
      setIsResizing(false);
    }, 50);
  };

  const handleMouseEnter = () => {
    document.body.style.overflow = "hidden"; // disable page scroll
  };

  const handleMouseLeave = () => {
    document.body.style.overflow = "auto"; // re-enable scroll
  };

  const refreshDisplay = () => {
    if (props.moleculeData != viewingData) {
      setViewingData(props.moleculeData);
    } else {
      if (miew) {
        //@ts-expect-error Miew class not implementing typescript correctly
        miew.resetView();
      }
    }
  };

  return (
    <div ref={molViewerRef} className="moleculeViewer">
      <div
        style={{
          width: "100%",
          height: "100%",
          backgroundColor: theme.colors.secondaryDark[7],
          borderRadius: "5px",
          overflow: "hidden",
        }}
        onMouseEnter={handleMouseEnter}
        onMouseLeave={handleMouseLeave}
      >
        {MemoViewer}
        {isResizing && viewingData && (
          <div
            style={{
              position: "absolute",
              inset: 0,
              display: "flex",
              alignItems: "center",
              justifyContent: "center",
              backgroundColor: theme.colors.secondaryDark[7], // optional dim
              opacity: 0.5,
              zIndex: 10,
            }}
          >
            <div
              style={{
                display: "flex",
                alignItems: "center",
                justifyContent: "center",
              }}
            >
              <IconArrowBarBoth size={80} />
            </div>
          </div>
        )}
      </div>
      {props.selectedAtom && (
        <Paper className="atomEditor" radius="md" p="md">
          <MoleculeViewerMenu selectedAtom={props.selectedAtom} miew={miew} />
        </Paper>
      )}

      <div
        style={{
          position: "absolute",
          left: "10px",
          top: "10px",
          display: "flex",
          zIndex: 5,
          width: "auto",
        }}
      >
        <UnstyledButton onClick={refreshDisplay}>
          <IconRefresh size={25} />
        </UnstyledButton>
      </div>
    </div>
  );
}

export default MoleculeViewer;