feat(frontend): implement light mode

frontend/src/App.vue

@@ -1,13 +1,15 @@
 <script setup>
-import { inject, provide } from 'vue'
+import { inject, provide, watchEffect } from 'vue'
 import { RouterView } from 'vue-router'
 
 import { useRequestsStateStore } from '@/stores/requestsState'
+import { useThemeStore } from '@/stores/theme'
 import NavigationBar from '@/components/NavigationBar.vue'
 import RequestsState from '@/components/RequestsState.vue'
 
 const axios = inject('axios')
 const requestsState = useRequestsStateStore()
+const theme = useThemeStore()
 
 /**
  * Universal data getter
@@ -27,6 +29,10 @@ async function getData(urlPath, ...params) {
 
 // Provide data getter to whole app
 provide('getData', getData)
+
+watchEffect(() => {
+  document.documentElement.setAttribute('data-bs-theme', theme.theme)
+})
 </script>
 
 <template>

frontend/src/components/ActivityClassBadge.vue

@@ -3,10 +3,12 @@ defineProps(['value'])
 </script>
 
 <template>
-  <span v-if="value == 'off'" class="badge bg-dark-subtle">
+  <span v-if="value == 'off'" class="badge bg-dark-subtle text-reset">
     <i class="fa fa-power-off me-2" aria-hidden="true"></i>Off
   </span>
-  <span v-else-if="value == 'idle'" class="badge bg-dark-subtle border border-white">Idle</span>
+  <span v-else-if="value == 'idle'" class="badge bg-dark-subtle border border-secondary text-reset"
+    >Idle</span
+  >
   <span v-else-if="value == 'light'" class="badge bg-info text-dark">Light</span>
   <span v-else-if="value == 'medium'" class="badge bg-warning text-dark">Medium</span>
   <span v-else-if="value == 'high'" class="badge bg-danger">High</span>

frontend/src/components/ActivityTimeline.vue

@@ -10,10 +10,13 @@ import {
   CHART_SCALE_X_OPTIONS,
   resampleTimedData,
   setChartDatetimeRange,
+  themeTextColor,
 } from '@/utils/commonCharts.js'
+import { useThemeStore } from '@/stores/theme'
+
+const themeStore = useThemeStore()
 
 ChartJS.register(...registerables, annotationPlugin)
-ChartJS.defaults.color = '#dee2e6'
 ChartJS.defaults.borderColor = '#495057'
 
 const props = defineProps({
@@ -44,12 +47,13 @@ const props = defineProps({
 })
 
 const CHART_UNITS = ['pkt', 'flw', 'B']
-const CHART_COLORS = ['#0DCAF0', '#198754', '#FFC107']
+const CHART_COLORS = ['#3498DB', '#198754', '#F39C12']
 
 const DIRECTION_PREFIX = props.incomingDirection ? 'in_' : 'out_'
 
 const chartOptions = computed(() => {
   let scaleXOptions = { ...CHART_SCALE_X_OPTIONS }
+  scaleXOptions.ticks.color = themeTextColor(themeStore.isDark)
 
   // Set the time range of the chart
   setChartDatetimeRange(scaleXOptions, props.timePickerState.from, props.timePickerState.to)

frontend/src/components/NavigationBar.vue

@@ -1,15 +1,25 @@
 <script setup>
 import { RouterLink, useRoute } from 'vue-router'
 
+import { useThemeStore } from '@/stores/theme'
+import ThemeToggle from '@/components/ThemeToggle.vue'
+
 const route = useRoute()
+const theme = useThemeStore()
 </script>
 
 <template>
   <nav class="navbar bg-body-tertiary navbar-expand-lg">
     <div class="container">
       <div class="navbar-brand">
         <RouterLink :to="{ name: 'home' }" class="navbar-brand">
-          <img src="@/assets/logo.svg" alt="PANDDA" class="logo" />
+          <img
+            v-if="theme.theme === 'dark'"
+            src="@/assets/logo-white.svg"
+            alt="PANDDA"
+            class="logo"
+          />
+          <img v-else src="@/assets/logo-black.svg" alt="PANDDA" class="logo" />
         </RouterLink>
       </div>
       <button
@@ -19,8 +29,8 @@ const route = useRoute()
       >
         <span class="navbar-toggler-icon"></span>
       </button>
-      <div class="collapse navbar-collapse row" id="navbarSupportedContent">
-        <ul class="navbar-nav px-2">
+      <div class="collapse navbar-collapse" id="navbarSupportedContent">
+        <ul class="navbar-nav px-2 me-auto">
           <li class="nav-item">
             <RouterLink
               :to="{ name: 'home' }"
@@ -42,6 +52,9 @@ const route = useRoute()
             </RouterLink>
           </li>
         </ul>
+        <div class="m-2">
+          <ThemeToggle />
+        </div>
       </div>
     </div>
   </nav>

frontend/src/components/ObservationsTimeline.vue

@@ -10,10 +10,13 @@ import {
   CHART_SCALE_X_OPTIONS,
   resampleTimedData,
   setChartDatetimeRange,
+  themeTextColor,
 } from '@/utils/commonCharts.js'
+import { useThemeStore } from '@/stores/theme'
+
+const themeStore = useThemeStore()
 
 ChartJS.register(...registerables, annotationPlugin)
-ChartJS.defaults.color = '#dee2e6'
 ChartJS.defaults.borderColor = '#495057'
 
 const props = defineProps({
@@ -55,6 +58,7 @@ const props = defineProps({
 
 const chartOptions = computed(() => {
   let scaleXOptions = { ...CHART_SCALE_X_OPTIONS }
+  scaleXOptions.ticks.color = themeTextColor(themeStore.isDark)
 
   // Set the time range of the chart
   setChartDatetimeRange(scaleXOptions, props.timePickerState.from, props.timePickerState.to)
@@ -69,6 +73,7 @@ const chartOptions = computed(() => {
         offset: true,
         ticks: {
           display: true,
+          color: themeTextColor(themeStore.isDark),
         },
         grid: {
           display: false,

frontend/src/components/ThemeToggle.vue

@@ -0,0 +1,20 @@
+<template>
+  <button
+    type="button"
+    class="btn btn-dark"
+    :aria-label="isDark ? 'Switch to light mode' : 'Switch to dark mode'"
+    :title="isDark ? 'Switch to light mode' : 'Switch to dark mode'"
+    @click="theme.setTheme(isDark ? 'light' : 'dark')"
+  >
+    <span v-if="isDark" aria-hidden="true">☀️</span>
+    <span v-else aria-hidden="true">🌙</span>
+  </button>
+</template>
+
+<script setup>
+import { computed } from 'vue'
+import { useThemeStore } from '@/stores/theme'
+
+const theme = useThemeStore()
+const isDark = computed(() => theme.theme === 'dark')
+</script>

frontend/src/stores/theme.js

@@ -0,0 +1,33 @@
+import { ref, computed } from 'vue'
+import { defineStore } from 'pinia'
+
+/**
+ * Tracking of the current theme (dark or light).
+ */
+export const useThemeStore = defineStore('theme', () => {
+  const STORAGE_KEY = 'theme'
+  const theme = ref(initialTheme())
+
+  /**
+   * Determine the initial theme mode based on local storage or system preference.
+   */
+  function initialTheme() {
+    const saved = localStorage.getItem(STORAGE_KEY)
+    if (saved === 'dark' || saved === 'light') return saved
+    return window.matchMedia?.('(prefers-color-scheme: dark)').matches ? 'dark' : 'light'
+  }
+
+  /**
+   * Sets the current theme.
+   */
+  function setTheme(newTheme) {
+    theme.value = newTheme === 'dark' ? 'dark' : 'light'
+    localStorage.setItem(STORAGE_KEY, theme.value)
+  }
+
+  return {
+    theme: computed(() => theme.value),
+    isDark: computed(() => theme.value === 'dark'),
+    setTheme,
+  }
+})

frontend/src/utils/commonCharts.js

@@ -35,6 +35,13 @@ export const CHART_COMMON_OPTIONS = {
   maintainAspectRatio: false,
 }
 
+/**
+ * Gets text color based on current theme
+ */
+export function themeTextColor(isDark) {
+  return isDark ? '#DEE2E6' : '#212529'
+}
+
 /**
  * Sets chart datetime range if both `dtFrom` and `dtTo` are provided
  * @param {Object} chartScaleXOptions Options for the X axis