import { useState, useEffect, useRef } from "react";
import shortid from "shortid";
import { Group } from "react-konva";
import Konva from "konva";

import { useInteractionEmitter } from "../../contexts/MapInteractionContext";
import { useMapStage } from "../../contexts/MapStageContext";
import { useUserId } from "../../contexts/UserIdContext";

import Vector2 from "../../helpers/Vector2";
import { getRelativePointerPosition } from "../../helpers/konva";

import useGridSnapping from "../../hooks/useGridSnapping";

import Note from "../note/Note";

import { Map } from "../../types/Map";
import { Note as NoteType } from "../../types/Note";
import {
  NoteAddEventHander,
  NoteChangeEventHandler,
  NoteDragEventHandler,
  NoteMenuOpenEventHandler,
} from "../../types/Events";

const defaultNoteSize = 2;

type MapNoteProps = {
  map: Map;
  active: boolean;
  onNoteAdd: NoteAddEventHander;
  onNoteChange: NoteChangeEventHandler;
  notes: NoteType[];
  onNoteMenuOpen: NoteMenuOpenEventHandler;
  draggable: boolean;
  onNoteDragStart: NoteDragEventHandler;
  onNoteDragEnd: NoteDragEventHandler;
  fadeOnHover: boolean;
};

function MapNotes({
  map,
  active,
  onNoteAdd,
  onNoteChange,
  notes,
  onNoteMenuOpen,
  draggable,
  onNoteDragStart,
  onNoteDragEnd,
  fadeOnHover,
}: MapNoteProps) {
  const interactionEmitter = useInteractionEmitter();
  const userId = useUserId();
  const mapStageRef = useMapStage();
  const [isBrushDown, setIsBrushDown] = useState(false);
  const [noteData, setNoteData] = useState<NoteType | null>(null);

  const creatingNoteRef = useRef<Konva.Group>(null);

  const snapPositionToGrid = useGridSnapping();

  useEffect(() => {
    if (!active) {
      return;
    }
    const mapStage = mapStageRef.current;

    function getBrushPosition() {
      if (!mapStage) {
        return;
      }
      const mapImage = mapStage.findOne("#mapImage");
      let position = getRelativePointerPosition(mapImage);
      if (!position) {
        return;
      }
      if (map.snapToGrid) {
        position = snapPositionToGrid(position);
      }
      return Vector2.divide(position, {
        x: mapImage.width(),
        y: mapImage.height(),
      });
    }

    function handleBrushDown() {
      const brushPosition = getBrushPosition();
      if (!brushPosition || !userId) {
        return;
      }
      setNoteData({
        x: brushPosition.x,
        y: brushPosition.y,
        size: defaultNoteSize,
        text: "",
        id: shortid.generate(),
        lastModified: Date.now(),
        lastModifiedBy: userId,
        visible: true,
        locked: false,
        color: "yellow",
        textOnly: false,
      });
      setIsBrushDown(true);
    }

    function handleBrushMove() {
      if (noteData) {
        const brushPosition = getBrushPosition();
        if (!brushPosition) {
          return;
        }
        setNoteData((prev) => {
          if (!prev) {
            return prev;
          }
          return {
            ...prev,
            x: brushPosition.x,
            y: brushPosition.y,
          };
        });
        setIsBrushDown(true);
      }
    }

    function handleBrushUp() {
      if (noteData && creatingNoteRef.current) {
        onNoteAdd(noteData);
        onNoteMenuOpen(noteData.id, creatingNoteRef.current);
      }
      setNoteData(null);
      setIsBrushDown(false);
    }

    interactionEmitter?.on("dragStart", handleBrushDown);
    interactionEmitter?.on("drag", handleBrushMove);
    interactionEmitter?.on("dragEnd", handleBrushUp);

    return () => {
      interactionEmitter?.off("dragStart", handleBrushDown);
      interactionEmitter?.off("drag", handleBrushMove);
      interactionEmitter?.off("dragEnd", handleBrushUp);
    };
  });

  return (
    <Group>
      {notes.map((note) => (
        <Note
          note={note}
          map={map}
          key={note.id}
          onNoteMenuOpen={onNoteMenuOpen}
          draggable={draggable && !note.locked}
          onNoteChange={onNoteChange}
          onNoteDragStart={onNoteDragStart}
          onNoteDragEnd={onNoteDragEnd}
          fadeOnHover={fadeOnHover}
        />
      ))}
      <Group ref={creatingNoteRef}>
        {isBrushDown && noteData && <Note note={noteData} map={map} />}
      </Group>
    </Group>
  );
}

export default MapNotes;