Fix dark mode graph labels for system theme and improve colors

- Fix dark mode detection to work when theme is set to 'system'
- Add real-time system theme change detection
- Update label colors from cyan to white for better readability
- Update edge colors to medium gray (#888888) for better contrast
- Add development feature: random graph generator button in settings
- Enhance random graph with edge attributes and labels
- Install missing graphology layout dependencies

lightrag_webui/package.json

@@ -43,6 +43,10 @@
     "cmdk": "^1.0.4",
     "graphology": "^0.26.0",
     "graphology-generators": "^0.11.2",
+    "graphology-layout": "^0.6.1",
+    "graphology-layout-force": "^0.2.4",
+    "graphology-layout-forceatlas2": "^0.10.1",
+    "graphology-layout-noverlap": "^0.4.2",
     "i18next": "^24.2.2",
     "katex": "^0.16.22",
     "lucide-react": "^0.475.0",
@@ -56,6 +60,7 @@
     "react-markdown": "^9.1.0",
     "react-number-format": "^5.4.3",
     "react-router-dom": "^7.3.0",
+    "react-select": "^5.10.2",
     "react-syntax-highlighter": "^15.6.1",
     "rehype-katex": "^7.0.1",
     "rehype-react": "^8.0.0",

lightrag_webui/src/components/graph/GraphControl.tsx

@@ -2,7 +2,7 @@ import { useRegisterEvents, useSetSettings, useSigma } from '@react-sigma/core'
 import { AbstractGraph } from 'graphology-types'
 // import { useLayoutCircular } from '@react-sigma/layout-circular'
 import { useLayoutForceAtlas2 } from '@react-sigma/layout-forceatlas2'
-import { useEffect } from 'react'
+import { useEffect, useState } from 'react'
 
 // import useRandomGraph, { EdgeType, NodeType } from '@/hooks/useRandomGraph'
 import { EdgeType, NodeType } from '@/hooks/useLightragGraph'
@@ -43,6 +43,20 @@ const GraphControl = ({ disableHoverEffect }: { disableHoverEffect?: boolean })
   const selectedEdge = useGraphStore.use.selectedEdge()
   const focusedEdge = useGraphStore.use.focusedEdge()
   const sigmaGraph = useGraphStore.use.sigmaGraph()
+  
+  // Track system theme changes when theme is set to 'system'
+  const [systemThemeIsDark, setSystemThemeIsDark] = useState(() => 
+    window.matchMedia('(prefers-color-scheme: dark)').matches
+  )
+  
+  useEffect(() => {
+    if (theme === 'system') {
+      const mediaQuery = window.matchMedia('(prefers-color-scheme: dark)')
+      const handler = (e: MediaQueryListEvent) => setSystemThemeIsDark(e.matches)
+      mediaQuery.addEventListener('change', handler)
+      return () => mediaQuery.removeEventListener('change', handler)
+    }
+  }, [theme])
 
   /**
    * When component mount or maxIterations changes
@@ -194,7 +208,9 @@ const GraphControl = ({ disableHoverEffect }: { disableHoverEffect?: boolean })
    * => Setting the sigma reducers
    */
   useEffect(() => {
-    const isDarkTheme = theme === 'dark'
+    // Check if dark mode is actually applied (handles both 'dark' theme and 'system' theme when OS is dark)
+    const isDarkTheme = theme === 'dark' || 
+      (theme === 'system' && window.document.documentElement.classList.contains('dark'))
     const labelColor = isDarkTheme ? Constants.labelColorDarkTheme : undefined
     const edgeColor = isDarkTheme ? Constants.edgeColorDarkTheme : undefined
 
@@ -298,6 +314,7 @@ const GraphControl = ({ disableHoverEffect }: { disableHoverEffect?: boolean })
     sigma,
     disableHoverEffect,
     theme,
+    systemThemeIsDark,
     hideUnselectedEdges,
     enableEdgeEvents,
     renderEdgeLabels,

lightrag_webui/src/components/graph/Settings.tsx

@@ -7,8 +7,10 @@ import Input from '@/components/ui/Input'
 
 import { controlButtonVariant } from '@/lib/constants'
 import { useSettingsStore } from '@/stores/settings'
+import { useGraphStore } from '@/stores/graph'
+import useRandomGraph from '@/hooks/useRandomGraph'
 
-import { SettingsIcon, Undo2 } from 'lucide-react'
+import { SettingsIcon, Undo2, Shuffle } from 'lucide-react'
 import { useTranslation } from 'react-i18next';
 
 /**
@@ -163,6 +165,9 @@ export default function Settings() {
 
   const enableHealthCheck = useSettingsStore.use.enableHealthCheck()
 
+  // Random graph functionality for development/testing
+  const { randomGraph } = useRandomGraph()
+
   const setEnableNodeDrag = useCallback(
     () => useSettingsStore.setState((pre) => ({ enableNodeDrag: !pre.enableNodeDrag })),
     []
@@ -228,6 +233,11 @@ export default function Settings() {
     useSettingsStore.setState({ graphLayoutMaxIterations: iterations })
   }, [])
 
+  const handleGenerateRandomGraph = useCallback(() => {
+    const graph = randomGraph()
+    useGraphStore.getState().setSigmaGraph(graph)
+  }, [randomGraph])
+
   const { t } = useTranslation();
 
   const saveSettings = () => setOpened(false);
@@ -376,6 +386,24 @@ export default function Settings() {
               defaultValue={15}
               onEditFinished={setGraphLayoutMaxIterations}
             />
+            <Separator />
+            
+            {/* Development/Testing Section */}
+            <div className="flex flex-col gap-2">
+              <label className="text-sm leading-none font-medium text-muted-foreground">
+                Development
+              </label>
+              <Button
+                onClick={handleGenerateRandomGraph}
+                variant="outline"
+                size="sm"
+                className="flex items-center gap-2"
+              >
+                <Shuffle className="h-3.5 w-3.5" />
+                Generate Random Graph
+              </Button>
+            </div>
+
             <Separator />
             <Button
               onClick={saveSettings}

lightrag_webui/src/hooks/useRandomGraph.tsx

@@ -56,6 +56,16 @@ const useRandomGraph = () => {
         image: faker.image.urlLoremFlickr()
       })
     })
+    
+    // Add edge attributes
+    graph.edges().forEach((edge: string) => {
+      graph.mergeEdgeAttributes(edge, {
+        label: faker.lorem.words(faker.number.int({ min: 1, max: 3 })),
+        size: faker.number.float({ min: 1, max: 5 }),
+        color: randomColor()
+      })
+    })
+    
     return graph as Graph<NodeType, EdgeType>
   }, [faker])
 

lightrag_webui/src/lib/constants.ts

@@ -5,16 +5,16 @@ export const webuiPrefix = '/webui/'
 
 export const controlButtonVariant: ButtonVariantType = 'ghost'
 
-export const labelColorDarkTheme = '#B2EBF2'
-export const LabelColorHighlightedDarkTheme = '#000'
+export const labelColorDarkTheme = '#FFFFFF'
+export const LabelColorHighlightedDarkTheme = '#000000'
 
 export const nodeColorDisabled = '#E2E2E2'
 export const nodeBorderColor = '#EEEEEE'
 export const nodeBorderColorSelected = '#F57F17'
 
-export const edgeColorDarkTheme = '#969696'
+export const edgeColorDarkTheme = '#888888'
 export const edgeColorSelected = '#F57F17'
-export const edgeColorHighlighted = '#B2EBF2'
+export const edgeColorHighlighted = '#FFFFFF'
 
 export const searchResultLimit = 50
 export const labelListLimit = 100