merge: Address technical dept in topology view (#162)

This pull request aims to address some of the technical debt in the topology 
view of the OpenDC frontend.

* Add support for panning of the datacenter topology
* Isolate world coordinate space (world objects do not depend on camera scale or position)
* Split transpiled modules into a separate chunk to reduce deduplication
* Encode state in topology actions to reduce global state
* Restructure components per page
* Enable more ESLint rules through `eslint:recommended` ruleset
* Move page components in separate files.

1 files changed, 55 insertions, 0 deletions

diff --git a/opendc-web/opendc-web-ui/src/components/topologies/map/layers/HoverLayerComponent.js b/opendc-web/opendc-web-ui/src/components/topologies/map/layers/HoverLayerComponent.js
new file mode 100644
index 00000000..2b1060c0
--- /dev/null
+++ b/opendc-web/opendc-web-ui/src/components/topologies/map/layers/HoverLayerComponent.js
@@ -0,0 +1,55 @@
+import PropTypes from 'prop-types'
+import React, { useMemo, useState } from 'react'
+import { Layer } from 'react-konva/lib/ReactKonva'
+import HoverTile from '../elements/HoverTile'
+import { TILE_SIZE_IN_PIXELS } from '../MapConstants'
+import { useEffectRef } from '../../../../util/effect-ref'
+
+function HoverLayerComponent({ isEnabled, isValid, onClick, children }) {
+    const [[mouseWorldX, mouseWorldY], setPos] = useState([0, 0])
+
+    const layerRef = useEffectRef((layer) => {
+        if (!layer) {
+            return
+        }
+
+        const stage = layer.getStage()
+
+        // Transform used to convert mouse coordinates to world coordinates
+        const transform = stage.getAbsoluteTransform().copy()
+        transform.invert()
+
+        stage.on('mousemove.hover', () => {
+            const { x, y } = transform.point(stage.getPointerPosition())
+            setPos([x, y])
+        })
+        return () => stage.off('mousemove.hover')
+    })
+
+    const gridX = Math.floor(mouseWorldX / TILE_SIZE_IN_PIXELS)
+    const gridY = Math.floor(mouseWorldY / TILE_SIZE_IN_PIXELS)
+    const valid = useMemo(() => isEnabled && isValid(gridX, gridY), [isEnabled, isValid, gridX, gridY])
+
+    if (!isEnabled) {
+        return <Layer />
+    }
+
+    const x = gridX * TILE_SIZE_IN_PIXELS
+    const y = gridY * TILE_SIZE_IN_PIXELS
+
+    return (
+        <Layer opacity={0.6} ref={layerRef}>
+            <HoverTile x={x} y={y} isValid={valid} onClick={() => (valid ? onClick(gridX, gridY) : undefined)} />
+            {children ? React.cloneElement(children, { x, y, scale: 1 }) : undefined}
+        </Layer>
+    )
+}
+
+HoverLayerComponent.propTypes = {
+    isEnabled: PropTypes.bool.isRequired,
+    isValid: PropTypes.func.isRequired,
+    onClick: PropTypes.func.isRequired,
+    children: PropTypes.node,
+}
+
+export default HoverLayerComponent