grungnet/src/components/DragOverlay.js
2021-01-04 12:22:09 +11:00

90 lines
2.4 KiB
JavaScript

import React, { useEffect, useRef, useState } from "react";
import { Box, IconButton } from "theme-ui";
import RemoveTokenIcon from "../icons/RemoveTokenIcon";
function DragOverlay({ dragging, node, onRemove }) {
const [isRemoveHovered, setIsRemoveHovered] = useState(false);
const removeTokenRef = useRef();
// Detect token hover on remove icon manually to support touch devices
useEffect(() => {
const map = document.querySelector(".map");
const mapRect = map.getBoundingClientRect();
function detectRemoveHover() {
if (!node || !dragging || !removeTokenRef.current) {
return;
}
const stage = node.getStage();
if (!stage) {
return;
}
const pointerPosition = stage.getPointerPosition();
const screenSpacePointerPosition = {
x: pointerPosition.x + mapRect.left,
y: pointerPosition.y + mapRect.top,
};
const removeIconPosition = removeTokenRef.current.getBoundingClientRect();
if (
screenSpacePointerPosition.x > removeIconPosition.left &&
screenSpacePointerPosition.y > removeIconPosition.top &&
screenSpacePointerPosition.x < removeIconPosition.right &&
screenSpacePointerPosition.y < removeIconPosition.bottom
) {
if (!isRemoveHovered) {
setIsRemoveHovered(true);
}
} else if (isRemoveHovered) {
setIsRemoveHovered(false);
}
}
let handler;
if (node && dragging) {
handler = setInterval(detectRemoveHover, 100);
}
return () => {
if (handler) {
clearInterval(handler);
}
};
}, [isRemoveHovered, dragging, node]);
// Detect drag end of token image and remove it if it is over the remove icon
useEffect(() => {
if (!dragging && node && isRemoveHovered) {
onRemove();
}
});
return (
dragging && (
<Box
sx={{
position: "absolute",
bottom: "32px",
left: "50%",
borderRadius: "50%",
transform: isRemoveHovered
? "translateX(-50%) scale(2.0)"
: "translateX(-50%) scale(1.5)",
transition: "transform 250ms ease",
color: isRemoveHovered ? "primary" : "text",
pointerEvents: "none",
}}
bg="overlay"
ref={removeTokenRef}
>
<IconButton>
<RemoveTokenIcon />
</IconButton>
</Box>
)
);
}
export default DragOverlay;