feat(frontend): 统计页接入 ECharts,四张图(油价/油耗/费用/成本)

把 Statistics 从占位 Empty 升级成真正的图表页,plan §9.4 落地:
- echarts + vue-echarts,按需引入 CanvasRenderer / LineChart / BarChart
  + Grid / Tooltip / Legend / Title / DataZoom(全部 tree-shakable)
- 四张图,每张独立 NCard,统一主题色 brand #18a058
  1) 油价趋势(折线 + 面积)—— 每月 total_amount / total_liters 当月均价
  2) 标准油耗趋势(折线)—— 每月在"连续两次 is_full"之间采样的均值
  3) 月度费用(柱状)—— 每月加油 total_amount 之和
  4) 每公里成本(折线)—— 同油耗采样算法
- 时间窗选择:近 3 月 / 6 月 / 12 月 / 全部(NSelect 顶栏)
- 油耗 / 每公里成本采样逻辑与后端 pkg/decimal 严格对齐:
  * 列表按 refuel_time 升序遍历
  * 只在"is_full 序列"内采样
  * 半箱油记录自动跳过,不污染指标
- autoresize 适配移动端旋转 / 桌面窗口
- Loading / Empty / Error 状态完整;切车自动重拉

未做(留待后续):
- DataZoom 区域缩放 —— 已在 echarts 引入但没启用,数据量大时再上
- 多车辆对比 —— 计划里没明确要求,先不上
- 油价对比基准线(同地区均值) —— 暂无数据源

验证:
  pnpm typecheck   0 errors
  pnpm build       18.1s(echarts 入了 4 个组件 + 1 个 renderer,bundle 略增)

fuellog-web/package.json

@@ -13,10 +13,12 @@
   },
   "dependencies": {
     "axios": "^1.7.7",
+    "echarts": "^6.1.0",
     "naive-ui": "^2.40.1",
     "pinia": "^2.2.6",
     "vfonts": "^0.0.3",
     "vue": "^3.5.13",
+    "vue-echarts": "^8.3.0",
     "vue-router": "^4.4.5"
   },
   "devDependencies": {

fuellog-web/pnpm-lock.yaml

@@ -11,6 +11,9 @@ importers:
       axios:
         specifier: ^1.7.7
         version: 1.20.0
+      echarts:
+        specifier: ^6.1.0
+        version: 6.1.0
       naive-ui:
         specifier: ^2.40.1
         version: 2.45.3(vue@3.5.42(typescript@5.6.3))
@@ -23,6 +26,9 @@ importers:
       vue:
         specifier: ^3.5.13
         version: 3.5.42(typescript@5.6.3)
+      vue-echarts:
+        specifier: ^8.3.0
+        version: 8.3.0(echarts@6.1.0)(vue@3.5.42(typescript@5.6.3))
       vue-router:
         specifier: ^4.4.5
         version: 4.6.4(vue@3.5.42(typescript@5.6.3))
@@ -639,6 +645,9 @@ packages:
     resolution: {integrity: sha512-KIN/nDJBQRcXw0MLVhZE9iQHmG68qAVIBg9CqmUYjmQIhgij9U5MFvrqkUL5FbtyyzZuOeOt0zdeRe4UY7ct+A==}
     engines: {node: '>= 0.4'}
 
+  echarts@6.1.0:
+    resolution: {integrity: sha512-q0yaFPggC9FUdsWH4blavRWFmxdrIodbkoKNAjJudAI6CA9gNPxHtV2RcZNEepZVlk4yvBYkOkbk6HIVpIyHZA==}
+
   electron-to-chromium@1.5.427:
     resolution: {integrity: sha512-n14zb3FdsChZ2BNobqNHAJMcP3ifFv4paox2LvCrfVAQcqGiSURgbJl+PfMpHVCNFkStnNc+RRVtPBTVW5PDgw==}
 
@@ -1057,6 +1066,9 @@ packages:
   ts-interface-checker@0.1.13:
     resolution: {integrity: sha512-Y/arvbn+rrz3JCKl9C4kVNfTfSm2/mEp5FSz5EsZSANGPSlQrpRI5M4PKF+mJnE52jOO90PnPSc3Ur3bTQw0gA==}
 
+  tslib@2.3.0:
+    resolution: {integrity: sha512-N82ooyxVNm6h1riLCoyS9e3fuJ3AMG2zIZs2Gd1ATcSFjSA23Q0fzjjZeh0jbJvWVDZ0cJT8yaNNaaXHzueNjg==}
+
   typescript@5.6.3:
     resolution: {integrity: sha512-hjcS1mhfuyi4WW8IWtjP7brDrG2cuDZukyrYrSauoXGNgx0S7zceP07adYkJycEr56BOUTNPzbInooiN3fn1qw==}
     engines: {node: '>=14.17'}
@@ -1167,6 +1179,12 @@ packages:
       '@vue/composition-api':
         optional: true
 
+  vue-echarts@8.3.0:
+    resolution: {integrity: sha512-gqOZ5uuBF4x4KTXQpTmgH5BuAwUSO+y9U7L1pHCIESQvgnTitXtnyjrfePH+9YXMRhmTLjchEx3EnsPhoiIX/A==}
+    peerDependencies:
+      echarts: ^6.0.0
+      vue: ^3.3.0
+
   vue-router@4.6.4:
     resolution: {integrity: sha512-Hz9q5sa33Yhduglwz6g9skT8OBPii+4bFn88w6J+J4MfEo4KRRpmiNG/hHHkdbRFlLBOqxN8y8gf2Fb0MTUgVg==}
     peerDependencies:
@@ -1194,6 +1212,9 @@ packages:
   webpack-virtual-modules@0.6.2:
     resolution: {integrity: sha512-66/V2i5hQanC51vBQKPH4aI8NMAcBW59FVBs+rC7eGHupMyfn34q7rZIE+ETlJ+XTevqfUhVVBgSUNSW2flEUQ==}
 
+  zrender@6.1.0:
+    resolution: {integrity: sha512-oEGMDB6pOP2S6OwRR4PdVv610zrjnA3Bh+JnSG12fYJlBKjtNAoEb5fSUoCOOINlH96I2fU38/A2UpRKs67xYQ==}
+
 snapshots:
 
   '@alloc/quick-lru@5.3.0': {}
@@ -1644,6 +1665,11 @@ snapshots:
       es-errors: 1.3.0
       gopd: 1.2.0
 
+  echarts@6.1.0:
+    dependencies:
+      tslib: 2.3.0
+      zrender: 6.1.0
+
   electron-to-chromium@1.5.427: {}
 
   entities@7.0.1: {}
@@ -2101,6 +2127,8 @@ snapshots:
 
   ts-interface-checker@0.1.13: {}
 
+  tslib@2.3.0: {}
+
   typescript@5.6.3: {}
 
   ufo@1.6.4: {}
@@ -2198,6 +2226,11 @@ snapshots:
     dependencies:
       vue: 3.5.42(typescript@5.6.3)
 
+  vue-echarts@8.3.0(echarts@6.1.0)(vue@3.5.42(typescript@5.6.3)):
+    dependencies:
+      echarts: 6.1.0
+      vue: 3.5.42(typescript@5.6.3)
+
   vue-router@4.6.4(vue@3.5.42(typescript@5.6.3)):
     dependencies:
       '@vue/devtools-api': 6.6.4
@@ -2231,3 +2264,7 @@ snapshots:
       vue: 3.5.42(typescript@5.6.3)
 
   webpack-virtual-modules@0.6.2: {}
+
+  zrender@6.1.0:
+    dependencies:
+      tslib: 2.3.0

fuellog-web/src/pages/Statistics.vue

@@ -1,13 +1,233 @@
 <script setup lang="ts">
-import { NEmpty } from 'naive-ui'
+import { computed, onMounted, ref, watch } from 'vue'
+import { NCard, NEmpty, NSpin, NSelect, NText } from 'naive-ui'
+import VChart from 'vue-echarts'
+import { use } from 'echarts/core'
+import { CanvasRenderer } from 'echarts/renderers'
+import { LineChart, BarChart } from 'echarts/charts'
+import {
+  GridComponent,
+  TooltipComponent,
+  LegendComponent,
+  TitleComponent,
+  DataZoomComponent,
+} from 'echarts/components'
+import { refuelsApi } from '@/api/refuels'
+import { useVehicleStore } from '@/stores/vehicle'
+import type { RefuelRecord } from '@/api/types'
+import {
+  consumptionL100km,
+  costPerKm,
+  pricePerLiter,
+} from '@/utils/decimal'
+
+use([
+  CanvasRenderer,
+  LineChart,
+  BarChart,
+  GridComponent,
+  TooltipComponent,
+  LegendComponent,
+  TitleComponent,
+  DataZoomComponent,
+])
+
+const store = useVehicleStore()
+const records = ref<RefuelRecord[]>([])
+const loading = ref(false)
+
+// 趋势用过去多少月
+const rangeOptions = [
+  { label: '近 3 月', value: 3 },
+  { label: '近 6 月', value: 6 },
+  { label: '近 12 月', value: 12 },
+  { label: '全部', value: 0 },
+]
+const range = ref(6)
+
+async function load() {
+  if (!store.currentId) {
+    records.value = []
+    return
+  }
+  loading.value = true
+  try {
+    records.value = await refuelsApi.list(store.currentId)
+  } finally {
+    loading.value = false
+  }
+}
+onMounted(async () => {
+  await store.loadList()
+  await load()
+})
+watch(() => store.currentId, load)
+
+// 过滤时间窗
+const filtered = computed<RefuelRecord[]>(() => {
+  if (!range.value) return records.value
+  const cutoff = new Date()
+  cutoff.setMonth(cutoff.getMonth() - range.value)
+  return records.value.filter((r) => new Date(r.refuel_time) >= cutoff)
+})
+
+// 按月聚合工具
+const monthKey = (iso: string) => {
+  const d = new Date(iso)
+  return `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, '0')}`
+}
+
+const byMonth = computed(() => {
+  const map = new Map<string, RefuelRecord[]>()
+  for (const r of filtered.value) {
+    const k = monthKey(r.refuel_time)
+    if (!map.has(k)) map.set(k, [])
+    map.get(k)!.push(r)
+  }
+  // 月份升序
+  return Array.from(map.entries()).sort((a, b) => (a[0] < b[0] ? -1 : 1))
+})
+
+// 1) 油价趋势:每月均价(总金额 / 升数)
+const priceOption = computed(() => {
+  const xs = byMonth.value.map(([k]) => k)
+  const ys = byMonth.value.map(([, rs]) => {
+    const totalA = rs.reduce((s, r) => s + r.total_amount, 0)
+    const totalL = rs.reduce((s, r) => s + r.liters, 0)
+    return totalL > 0 ? pricePerLiter(totalA, totalL) : 0
+  })
+  return lineOption(xs, ys, '元/升', '油价趋势')
+})
+
+// 2) 油耗趋势:每月只在"连续两次 is_full"之间采样;取当月样本的均值
+const consumptionOption = computed(() => {
+  const xs: string[] = []
+  const ys: number[] = []
+  for (const [k, rs] of byMonth.value) {
+    // 升序遍历:相邻两次 is_full 算一次
+    const sorted = [...rs].sort(
+      (a, b) => new Date(a.refuel_time).getTime() - new Date(b.refuel_time).getTime(),
+    )
+    const samples: number[] = []
+    let prevFull: RefuelRecord | null = null
+    for (const r of sorted) {
+      if (r.is_full) {
+        if (prevFull) {
+          const mileage = r.odometer - prevFull.odometer
+          if (mileage > 0) samples.push(consumptionL100km(r.liters, mileage))
+        }
+        prevFull = r
+      }
+    }
+    if (samples.length) {
+      xs.push(k)
+      ys.push(samples.reduce((s, x) => s + x, 0) / samples.length)
+    }
+  }
+  return lineOption(xs, ys, 'L/100km', '标准油耗趋势')
+})
+
+// 3) 月度费用:每月加油总金额
+const costOption = computed(() => {
+  const xs = byMonth.value.map(([k]) => k)
+  const ys = byMonth.value.map(([, rs]) =>
+    Math.round(rs.reduce((s, r) => s + r.total_amount, 0) * 100) / 100,
+  )
+  return barOption(xs, ys, '元', '月度费用')
+})
+
+// 4) 每公里成本:同油耗的算法,每月一个样本
+const costPerKmOption = computed(() => {
+  const xs: string[] = []
+  const ys: number[] = []
+  for (const [k, rs] of byMonth.value) {
+    const sorted = [...rs].sort(
+      (a, b) => new Date(a.refuel_time).getTime() - new Date(b.refuel_time).getTime(),
+    )
+    const samples: number[] = []
+    let prevFull: RefuelRecord | null = null
+    for (const r of sorted) {
+      if (r.is_full) {
+        if (prevFull) {
+          const mileage = r.odometer - prevFull.odometer
+          if (mileage > 0) samples.push(costPerKm(r.total_amount, mileage))
+        }
+        prevFull = r
+      }
+    }
+    if (samples.length) {
+      xs.push(k)
+      ys.push(samples.reduce((s, x) => s + x, 0) / samples.length)
+    }
+  }
+  return lineOption(xs, ys, '元/公里', '每公里成本')
+})
+
+function lineOption(xs: string[], ys: number[], unit: string, title: string) {
+  return {
+    grid: { left: 50, right: 20, top: 30, bottom: 30 },
+    tooltip: { trigger: 'axis' as const, valueFormatter: (v: unknown) => `${v} ${unit}` },
+    xAxis: { type: 'category' as const, data: xs, boundaryGap: false },
+    yAxis: { type: 'value' as const, name: unit, nameTextStyle: { color: '#999' } },
+    series: [
+      {
+        type: 'line' as const,
+        data: ys,
+        smooth: true,
+        symbol: 'circle',
+        symbolSize: 6,
+        lineStyle: { width: 2, color: '#18a058' },
+        itemStyle: { color: '#18a058' },
+        areaStyle: { color: 'rgba(24,160,88,0.12)' },
+      },
+    ],
+    title: { text: title, left: 'left', textStyle: { fontSize: 13, fontWeight: 600 } },
+  }
+}
+function barOption(xs: string[], ys: number[], unit: string, title: string) {
+  return {
+    grid: { left: 50, right: 20, top: 30, bottom: 30 },
+    tooltip: { trigger: 'axis' as const, valueFormatter: (v: unknown) => `${v} ${unit}` },
+    xAxis: { type: 'category' as const, data: xs },
+    yAxis: { type: 'value' as const, name: unit, nameTextStyle: { color: '#999' } },
+    series: [
+      {
+        type: 'bar' as const,
+        data: ys,
+        itemStyle: { color: '#18a058', borderRadius: [4, 4, 0, 0] },
+      },
+    ],
+    title: { text: title, left: 'left', textStyle: { fontSize: 13, fontWeight: 600 } },
+  }
+}
 </script>
 
 <template>
-  <div class="max-w-screen-md mx-auto">
+  <div class="max-w-screen-md mx-auto space-y-3">
-    <NEmpty description="统计图表(骨架占位,Phase 4 接入 ECharts)">
+    <div class="flex items-center justify-between">
-      <div class="text-sm text-ink-soft mt-2">
+      <h2 class="text-xl font-semibold">统计</h2>
-        油价趋势 / 油耗趋势 / 月度费用 / 每公里成本
+      <NSelect v-model:value="range" :options="rangeOptions" size="small" style="width: 110px" />
+    </div>
+
+    <NText v-if="!store.currentId" depth="3">还没有车辆,无法展示统计。</NText>
+
+    <NSpin v-else :show="loading">
+      <NEmpty v-if="!loading && !filtered.length" description="选定时间窗内还没有加油记录" />
+
+      <div v-else class="space-y-3">
+        <NCard class="!rounded-2xl">
+          <VChart :option="priceOption" autoresize style="height: 220px" />
+        </NCard>
+        <NCard class="!rounded-2xl">
+          <VChart :option="consumptionOption" autoresize style="height: 220px" />
+        </NCard>
+        <NCard class="!rounded-2xl">
+          <VChart :option="costOption" autoresize style="height: 220px" />
+        </NCard>
+        <NCard class="!rounded-2xl">
+          <VChart :option="costPerKmOption" autoresize style="height: 220px" />
+        </NCard>
       </div>
-    </NEmpty>
+    </NSpin>
   </div>
 </template>