From 2ecf690a66c4f3006bab87dccbc188985ecd85d6 Mon Sep 17 00:00:00 2001
From: Aria Minaei <aria.minaei@gmail.com>
Date: Sun, 5 Sep 2021 22:16:14 +0200
Subject: [PATCH] Fixed the dom playground

---
 packages/playground/src/dom/Scene.tsx  |  15 ++-
 packages/playground/src/dom/useDrag.ts | 150 +++++++++++++++++++++++++
 2 files changed, 160 insertions(+), 5 deletions(-)
 create mode 100644 packages/playground/src/dom/useDrag.ts

diff --git a/packages/playground/src/dom/Scene.tsx b/packages/playground/src/dom/Scene.tsx
index e75392b..9bee6e5 100644
--- a/packages/playground/src/dom/Scene.tsx
+++ b/packages/playground/src/dom/Scene.tsx
@@ -1,6 +1,6 @@
 import studio from '@theatre/studio'
-import type {UseDragOpts} from '@theatre/studio/uiComponents/useDrag'
-import useDrag from '@theatre/studio/uiComponents/useDrag'
+import type {UseDragOpts} from './useDrag'
+import useDrag from './useDrag'
 import React, {useLayoutEffect, useMemo, useState} from 'react'
 import type {IProject, ISheet} from '@theatre/core'
 import {types as t} from '@theatre/core'
@@ -105,14 +105,19 @@ export const Scene: React.FC<{project: IProject}> = ({project}) => {
     <div
       style={{
         position: 'absolute',
-        left: '20vw',
-        right: '20vw',
+        left: '0',
+        right: '0',
         top: 0,
-        bottom: '30vh',
+        bottom: '0',
         background: 'black',
       }}
     >
       <button
+        style={{
+          top: '16px',
+          left: '60px',
+          position: 'absolute',
+        }}
         onClick={() => {
           setBoxes((boxes) => [...boxes, String(++lastBoxId)])
         }}
diff --git a/packages/playground/src/dom/useDrag.ts b/packages/playground/src/dom/useDrag.ts
new file mode 100644
index 0000000..7f21101
--- /dev/null
+++ b/packages/playground/src/dom/useDrag.ts
@@ -0,0 +1,150 @@
+import {useLayoutEffect, useRef} from 'react'
+
+const noop = () => {}
+
+function createCursorLock(cursor: string) {
+  const el = document.createElement('div')
+  el.style.cssText = `
+    position: fixed;
+    top: 0;
+    right: 0;
+    bottom: 0;
+    left: 0;
+    z-index: 9999999;`
+
+  el.style.cursor = cursor
+  document.body.appendChild(el)
+  const relinquish = () => {
+    document.body.removeChild(el)
+  }
+
+  return relinquish
+}
+
+export type UseDragOpts = {
+  disabled?: boolean
+  dontBlockMouseDown?: boolean
+  lockCursorTo?: string
+  onDragStart?: (event: MouseEvent) => void | false
+  onDragEnd?: (dragHappened: boolean) => void
+  onDrag: (dx: number, dy: number, event: MouseEvent) => void
+}
+
+export default function useDrag(
+  target: HTMLElement | undefined | null,
+  opts: UseDragOpts,
+) {
+  const optsRef = useRef<typeof opts>(opts)
+  optsRef.current = opts
+
+  const modeRef = useRef<'dragStartCalled' | 'dragging' | 'notDragging'>(
+    'notDragging',
+  )
+
+  const stateRef = useRef<{
+    dragHappened: boolean
+    startPos: {
+      x: number
+      y: number
+    }
+  }>({dragHappened: false, startPos: {x: 0, y: 0}})
+
+  useLayoutEffect(() => {
+    if (!target) return
+
+    const getDistances = (event: MouseEvent): [number, number] => {
+      const {startPos} = stateRef.current
+      return [event.screenX - startPos.x, event.screenY - startPos.y]
+    }
+
+    let relinquishCursorLock = noop
+
+    const dragHandler = (event: MouseEvent) => {
+      if (!stateRef.current.dragHappened && optsRef.current.lockCursorTo) {
+        relinquishCursorLock = createCursorLock(optsRef.current.lockCursorTo)
+      }
+      if (!stateRef.current.dragHappened) stateRef.current.dragHappened = true
+      modeRef.current = 'dragging'
+
+      const deltas = getDistances(event)
+      optsRef.current.onDrag(deltas[0], deltas[1], event)
+    }
+
+    const dragEndHandler = () => {
+      removeDragListeners()
+      modeRef.current = 'notDragging'
+
+      optsRef.current.onDragEnd &&
+        optsRef.current.onDragEnd(stateRef.current.dragHappened)
+      relinquishCursorLock()
+      relinquishCursorLock = noop
+    }
+
+    const addDragListeners = () => {
+      document.addEventListener('mousemove', dragHandler)
+      document.addEventListener('mouseup', dragEndHandler)
+    }
+
+    const removeDragListeners = () => {
+      document.removeEventListener('mousemove', dragHandler)
+      document.removeEventListener('mouseup', dragEndHandler)
+    }
+
+    const preventUnwantedClick = (event: MouseEvent) => {
+      if (optsRef.current.disabled) return
+      if (stateRef.current.dragHappened) {
+        if (
+          !optsRef.current.dontBlockMouseDown &&
+          modeRef.current !== 'notDragging'
+        ) {
+          event.stopPropagation()
+          event.preventDefault()
+        }
+        stateRef.current.dragHappened = false
+      }
+    }
+
+    const dragStartHandler = (event: MouseEvent) => {
+      const opts = optsRef.current
+      if (opts.disabled === true) return
+
+      if (event.button !== 0) return
+      const resultOfStart = opts.onDragStart && opts.onDragStart(event)
+
+      if (resultOfStart === false) return
+
+      if (!opts.dontBlockMouseDown) {
+        event.stopPropagation()
+        event.preventDefault()
+      }
+
+      modeRef.current = 'dragStartCalled'
+
+      const {screenX, screenY} = event
+      stateRef.current.startPos = {x: screenX, y: screenY}
+      stateRef.current.dragHappened = false
+
+      addDragListeners()
+    }
+
+    const onMouseDown = (e: MouseEvent) => {
+      dragStartHandler(e)
+    }
+
+    target.addEventListener('mousedown', onMouseDown)
+    target.addEventListener('click', preventUnwantedClick)
+
+    return () => {
+      removeDragListeners()
+      target.removeEventListener('mousedown', onMouseDown)
+      target.removeEventListener('click', preventUnwantedClick)
+      relinquishCursorLock()
+
+      if (modeRef.current !== 'notDragging') {
+        optsRef.current.onDragEnd &&
+          optsRef.current.onDragEnd(modeRef.current === 'dragging')
+      }
+      modeRef.current = 'notDragging'
+    }
+  }, [target])
+}