GridMeasurementHelper component to continuously measure grid cells (#6517)

**Problem:**
When you reparent from a grid to another grid, for a single frame the
element blinks at the same cell position as it was in the original grid:
https://screenshot.click/09-31-10wrd-ysw94.mp4

**Root cause:**
As you hover over the target grid, the grid-reparent-strategy is
selected. It triggers a showGridControl command, so the grid control is
shown and the cells can be measured. However, it won't be able to
position to the real target cell in this frame yet, because the control
is not enabled yet, so we don't have the cell bounds in the metadata.

**Fix:**
Instead of using grid controls to measure let show permanent grid
measurement helpers so grids can always be measured.

**Commit Details:** (< vv pls delete this section if's not relevant)

- Added memoized function `getAllGrids` which returns all the grids from
the metadata
- Added `GridMeasurementHelper` component which renders a grid with
placeholder divs in its cells (similarly to `GridControl`, but much-much
simpler)
- Rendering `GridMeasurementHelper` for all grids
- Use rendered grid measurement helpers in dom-walker to measure the
size of grid cell bounds
- Remove all the hacks (most notably `getMetadataWithGridCellBounds`)
which made it possible to use latestMetadata in interaction when
startingMetadata did not include grid cell bounds. This is not needed
anymore, because the grid cells are always measured using the always-on
`GridMeasurementHelper` components

**Manual Tests:**
I hereby swear that:

- [x] I opened a hydrogen project and it loaded
- [x] I could navigate to various routes in Play mode

Author: gbalint

editor/src/components/canvas/canvas-strategies/strategies/grid-draw-to-insert-strategy.tsx

@@ -43,7 +43,7 @@ import {
   getStyleAttributesForFrameInAbsolutePosition,
   updateInsertionSubjectWithAttributes,
 } from './draw-to-insert-metastrategy'
-import { getMetadataWithGridCellBounds, setGridPropsCommands } from './grid-helpers'
+import { setGridPropsCommands } from './grid-helpers'
 import { newReparentSubjects } from './reparent-helpers/reparent-strategy-helpers'
 import { getReparentTargetUnified } from './reparent-helpers/reparent-strategy-parent-lookup'
 import { getGridCellUnderMouseFromMetadata } from './grid-cell-bounds'
@@ -132,13 +132,10 @@ const gridDrawToInsertStrategyInner =
       canvasState.propertyControlsInfo,
     )?.newParent.intendedParentPath
 
-    const { metadata: parent, customStrategyState: updatedCustomState } =
-      getMetadataWithGridCellBounds(
-        targetParent,
-        canvasState.startingMetadata,
-        interactionSession.latestMetadata,
-        customStrategyState,
-      )
+    const parent = MetadataUtils.findElementByElementPath(
+      canvasState.startingMetadata,
+      targetParent,
+    )
 
     if (targetParent == null || parent == null || !MetadataUtils.isGridLayoutedContainer(parent)) {
       return null
@@ -175,7 +172,6 @@ const gridDrawToInsertStrategyInner =
               updateHighlightedViews('mid-interaction', [targetParent]),
             ],
             [targetParent],
-            updatedCustomState ?? undefined,
           )
         }
 

editor/src/components/canvas/canvas-strategies/strategies/grid-helpers.ts

@@ -710,62 +710,6 @@ export function getGridRelatedIndexes(params: {
   return expandedRelatedIndexes[params.index] ?? []
 }
 
-export function getMetadataWithGridCellBounds(
-  path: ElementPath | null | undefined,
-  startingMetadata: ElementInstanceMetadataMap,
-  latestMetadata: ElementInstanceMetadataMap,
-  customStrategyState: CustomStrategyState,
-): {
-  metadata: ElementInstanceMetadata | null
-  customStrategyState: CustomStrategyState | null
-} {
-  if (path == null) {
-    return {
-      metadata: null,
-      customStrategyState: null,
-    }
-  }
-
-  const fromStartingMetadata = MetadataUtils.findElementByElementPath(startingMetadata, path)
-
-  if (fromStartingMetadata?.specialSizeMeasurements.gridCellGlobalFrames != null) {
-    return {
-      metadata: fromStartingMetadata,
-      customStrategyState: null,
-    }
-  }
-
-  const fromStrategyState = customStrategyState.grid.metadataCacheForGrids[EP.toString(path)]
-  if (fromStrategyState != null) {
-    return {
-      metadata: fromStrategyState,
-      customStrategyState: null,
-    }
-  }
-
-  const fromLatestMetadata = MetadataUtils.findElementByElementPath(latestMetadata, path)
-  if (fromLatestMetadata?.specialSizeMeasurements.gridCellGlobalFrames != null) {
-    return {
-      metadata: fromLatestMetadata,
-      customStrategyState: {
-        ...customStrategyState,
-        grid: {
-          ...customStrategyState.grid,
-          metadataCacheForGrids: {
-            ...customStrategyState.grid.metadataCacheForGrids,
-            [EP.toString(path)]: fromLatestMetadata,
-          },
-        },
-      },
-    }
-  }
-
-  return {
-    metadata: fromStartingMetadata,
-    customStrategyState: null,
-  }
-}
-
 function getOriginalElementGridConfiguration(
   gridCellGlobalFrames: GridCellGlobalFrames,
   interactionData: DragInteractionData,

editor/src/components/canvas/canvas-strategies/strategies/grid-reparent-strategy.tsx

@@ -17,7 +17,6 @@ import type { InsertionPath } from '../../../editor/store/insertion-path'
 import { CSSCursor } from '../../canvas-types'
 import { setCursorCommand } from '../../commands/set-cursor-command'
 import { propertyToSet, updateBulkProperties } from '../../commands/set-property-command'
-import { showGridControls } from '../../commands/show-grid-controls-command'
 import { updateSelectedViews } from '../../commands/update-selected-views-command'
 import { controlsForGridPlaceholders } from '../../controls/grid-controls-for-strategies'
 import { ParentBounds } from '../../controls/parent-bounds'
@@ -39,7 +38,7 @@ import {
 import type { DragInteractionData, InteractionSession, UpdatedPathMap } from '../interaction-state'
 import { honoursPropsPosition, shouldKeepMovingDraggedGroupChildren } from './absolute-utils'
 import { replaceFragmentLikePathsWithTheirChildrenRecursive } from './fragment-like-helpers'
-import { getMetadataWithGridCellBounds, runGridRearrangeMove } from './grid-helpers'
+import { runGridRearrangeMove } from './grid-helpers'
 import { ifAllowedToReparent, isAllowedToReparent } from './reparent-helpers/reparent-helpers'
 import { removeAbsolutePositioningProps } from './reparent-helpers/reparent-property-changes'
 import type { ReparentTarget } from './reparent-helpers/reparent-strategy-helpers'
@@ -164,13 +163,10 @@ export function applyGridReparent(
           return emptyStrategyApplicationResult
         }
 
-        const { metadata: grid, customStrategyState: updatedCustomState } =
-          getMetadataWithGridCellBounds(
-            newParent.intendedParentPath,
-            canvasState.startingMetadata,
-            interactionSession.latestMetadata,
-            customStrategyState,
-          )
+        const grid = MetadataUtils.findElementByElementPath(
+          canvasState.startingMetadata,
+          newParent.intendedParentPath,
+        )
 
         if (grid == null) {
           return strategyApplicationResult([], [newParent.intendedParentPath])
@@ -231,12 +227,6 @@ export function applyGridReparent(
           newParent.intendedParentPath,
         ])
 
-        const baseCustomState = updatedCustomState ?? customStrategyState
-        const customStrategyStatePatch = {
-          ...baseCustomState,
-          elementsToRerender: elementsToRerender,
-        }
-
         return strategyApplicationResult(
           [
             ...outcomes.flatMap((c) => c.commands),
@@ -245,7 +235,9 @@ export function applyGridReparent(
             setCursorCommand(CSSCursor.Reparent),
           ],
           elementsToRerender,
-          customStrategyStatePatch,
+          {
+            elementsToRerender: elementsToRerender,
+          },
         )
       },
     )

editor/src/components/canvas/canvas-strategies/strategies/grid-resize-element-strategy.ts

@@ -1,12 +1,10 @@
 import { MetadataUtils } from '../../../../core/model/element-metadata-utils'
 import * as EP from '../../../../core/shared/element-path'
-import type { GridElementProperties, GridPosition } from '../../../../core/shared/element-template'
 import {
   type CanvasRectangle,
   isInfinityRectangle,
   rectangleIntersection,
 } from '../../../../core/shared/math-utils'
-import { isCSSKeyword } from '../../../inspector/common/css-utils'
 import { isFillOrStretchModeApplied } from '../../../inspector/inspector-common'
 import {
   controlsForGridPlaceholders,
@@ -22,13 +20,12 @@ import {
   strategyApplicationResult,
 } from '../canvas-strategy-types'
 import type { InteractionSession } from '../interaction-state'
-import { getMetadataWithGridCellBounds, setGridPropsCommands } from './grid-helpers'
+import { setGridPropsCommands } from './grid-helpers'
 import { resizeBoundingBoxFromSide } from './resize-helpers'
 
 export const gridResizeElementStrategy: CanvasStrategyFactory = (
   canvasState: InteractionCanvasState,
   interactionSession: InteractionSession | null,
-  customState,
 ) => {
   const selectedElements = getTargetPathsFromInteractionTarget(canvasState.interactionTarget)
   if (selectedElements.length !== 1) {
@@ -86,13 +83,10 @@ export const gridResizeElementStrategy: CanvasStrategyFactory = (
         return emptyStrategyApplicationResult
       }
 
-      const { metadata: container, customStrategyState: updatedCustomState } =
-        getMetadataWithGridCellBounds(
-          EP.parentPath(selectedElement),
-          canvasState.startingMetadata,
-          interactionSession.latestMetadata,
-          customState,
-        )
+      const container = MetadataUtils.findElementByElementPath(
+        canvasState.startingMetadata,
+        EP.parentPath(selectedElement),
+      )
 
       if (container == null) {
         return emptyStrategyApplicationResult
@@ -123,7 +117,6 @@ export const gridResizeElementStrategy: CanvasStrategyFactory = (
       return strategyApplicationResult(
         setGridPropsCommands(selectedElement, gridTemplate, gridProps),
         [parentGridPath],
-        updatedCustomState ?? undefined,
       )
     },
   }

editor/src/components/canvas/controls/grid-controls-for-strategies.tsx

@@ -1,5 +1,6 @@
 /** @jsxRuntime classic */
 /** @jsx jsx */
+import fastDeepEqual from 'fast-deep-equal'
 import type { Sides } from 'utopia-api/core'
 import type { ElementPath } from 'utopia-shared/src/types'
 import { isStaticGridRepeat, printGridAutoOrTemplateBase } from '../../inspector/common/css-utils'
@@ -61,22 +62,72 @@ export function getNullableAutoOrTemplateBaseString(
   }
 }
 
-export type GridData = {
-  elementPath: ElementPath
+export type GridMeasurementHelperData = {
   frame: CanvasRectangle
   gridTemplateColumns: GridAutoOrTemplateBase | null
   gridTemplateRows: GridAutoOrTemplateBase | null
-  gridTemplateColumnsFromProps: GridAutoOrTemplateBase | null
-  gridTemplateRowsFromProps: GridAutoOrTemplateBase | null
   gap: number | null
-  justifyContent: string | null
-  alignContent: string | null
   rowGap: number | null
   columnGap: number | null
+  justifyContent: string | null
+  alignContent: string | null
   padding: Sides
-  rows: number
   columns: number
   cells: number
+}
+
+export function useGridMeasurentHelperData(
+  elementPath: ElementPath,
+): GridMeasurementHelperData | null {
+  return useEditorState(
+    Substores.metadata,
+    (store) => {
+      const element = MetadataUtils.findElementByElementPath(store.editor.jsxMetadata, elementPath)
+
+      const targetGridContainer = MetadataUtils.isGridLayoutedContainer(element) ? element : null
+
+      if (
+        targetGridContainer == null ||
+        targetGridContainer.globalFrame == null ||
+        !isFiniteRectangle(targetGridContainer.globalFrame)
+      ) {
+        return null
+      }
+
+      const columns = getCellsCount(
+        targetGridContainer.specialSizeMeasurements.containerGridProperties.gridTemplateColumns,
+      )
+      const rows = getCellsCount(
+        targetGridContainer.specialSizeMeasurements.containerGridProperties.gridTemplateRows,
+      )
+
+      return {
+        frame: targetGridContainer.globalFrame,
+        gridTemplateColumns:
+          targetGridContainer.specialSizeMeasurements.containerGridProperties.gridTemplateColumns,
+        gridTemplateRows:
+          targetGridContainer.specialSizeMeasurements.containerGridProperties.gridTemplateRows,
+        gap: targetGridContainer.specialSizeMeasurements.gap,
+        rowGap: targetGridContainer.specialSizeMeasurements.rowGap,
+        columnGap: targetGridContainer.specialSizeMeasurements.columnGap,
+        justifyContent: targetGridContainer.specialSizeMeasurements.justifyContent,
+        alignContent: targetGridContainer.specialSizeMeasurements.alignContent,
+        padding: targetGridContainer.specialSizeMeasurements.padding,
+        columns: columns,
+        cells: rows * columns,
+      }
+    },
+    'useGridMeasurentHelperData',
+    fastDeepEqual, //TODO: this should not be needed, but it seems EditorStateKeepDeepEquality is not running, and metadata reference is always updated
+  )
+}
+
+export type GridData = GridMeasurementHelperData & {
+  elementPath: ElementPath
+  gridTemplateColumnsFromProps: GridAutoOrTemplateBase | null
+  gridTemplateRowsFromProps: GridAutoOrTemplateBase | null
+  rows: number
+  cells: number
   metadata: ElementInstanceMetadata
 }
 
@@ -156,6 +207,12 @@ export const GridRowColumnResizingControls =
   )
 
 export const GridControlsKey = (gridPath: ElementPath) => `grid-controls-${EP.toString(gridPath)}`
+export const GridControlKey = (gridPath: ElementPath) => `grid-control-${EP.toString(gridPath)}`
+
+export const GridMeasurementHelpersKey = (gridPath: ElementPath) =>
+  `grid-measurement-helpers-${EP.toString(gridPath)}`
+export const GridMeasurementHelperKey = (gridPath: ElementPath) =>
+  `grid-measurement-helper-${EP.toString(gridPath)}`
 
 export interface GridControlProps {
   grid: GridData