import React, { useState } from "react";
import { createPortal } from "react-dom";
import {
  DndContext,
  DragOverlay,
  MouseSensor,
  TouchSensor,
  useSensor,
  useSensors,
  closestCenter,
} from "@dnd-kit/core";
import { SortableContext, arrayMove } from "@dnd-kit/sortable";
import { animated, useSpring, config } from "react-spring";
import { Grid } from "theme-ui";

import { combineGroups, moveGroups } from "../../helpers/group";

import useResponsiveLayout from "../../hooks/useResponsiveLayout";

import SortableTile from "./SortableTile";

function SortableTiles({
  groups,
  onGroupChange,
  renderTile,
  onTileSelect,
  disableGrouping,
}) {
  const layout = useResponsiveLayout();

  const mouseSensor = useSensor(MouseSensor, {
    activationConstraint: { delay: 250, tolerance: 5 },
  });
  const touchSensor = useSensor(TouchSensor, {
    activationConstraint: { delay: 250, tolerance: 5 },
  });

  const sensors = useSensors(mouseSensor, touchSensor);

  const [dragId, setDragId] = useState();
  const [overId, setOverId] = useState();

  function handleDragStart({ active, over }) {
    setDragId(active.id);
    setOverId(over?.id);
    onTileSelect(active.id);
  }

  function handleDragMove({ over }) {
    setOverId(over?.id);
  }

  function handleDragEnd({ active, over }) {
    setDragId();
    setOverId();
    if (!active || !over) {
      return;
    }

    if (over.id.startsWith("__group__")) {
      const overId = over.id.slice(9);
      if (overId === active.id) {
        return;
      }
      const activeGroupIndex = groups.findIndex(
        (group) => group.id === active.id
      );
      const overGroupIndex = groups.findIndex((group) => group.id === overId);
      onGroupChange(moveGroups(groups, overGroupIndex, activeGroupIndex));
      onTileSelect();
    } else if (active.id !== over.id) {
      const oldIndex = groups.findIndex((group) => group.id === active.id);
      const newIndex = groups.findIndex((group) => group.id === over.id);
      onGroupChange(arrayMove(groups, oldIndex, newIndex));
    }
  }

  const dragBounce = useSpring({
    transform: !!dragId ? "scale(0.9)" : "scale(1)",
    config: config.wobbly,
  });

  const overGroupId =
    overId && overId.startsWith("__group__") && overId.slice(9);

  function renderSortableGroup(group) {
    if (overGroupId === group.id && dragId && group.id !== dragId) {
      // If dragging over a group render a preview of that group
      return renderTile(
        combineGroups(
          group,
          groups.find((group) => group.id === dragId)
        )
      );
    }
    return renderTile(group);
  }

  return (
    <DndContext
      onDragStart={handleDragStart}
      onDragMove={handleDragMove}
      onDragEnd={handleDragEnd}
      sensors={sensors}
      collisionDetection={closestCenter}
    >
      <SortableContext items={groups}>
        <Grid
          p={3}
          pb={4}
          sx={{
            borderRadius: "4px",
            overflow: "hidden",
          }}
          gap={2}
          columns={layout.gridTemplate}
          onClick={() => onTileSelect()}
        >
          {groups.map((group) => (
            <SortableTile
              id={group.id}
              key={group.id}
              disableGrouping={disableGrouping}
            >
              {renderSortableGroup(group)}
            </SortableTile>
          ))}
        </Grid>
        {createPortal(
          <DragOverlay dropAnimation={null}>
            {dragId && (
              <animated.div style={dragBounce}>
                {renderTile(groups.find((group) => group.id === dragId))}
              </animated.div>
            )}
          </DragOverlay>,
          document.body
        )}
      </SortableContext>
    </DndContext>
  );
}

export default SortableTiles;