#カスタムチャート設定

return {
  dataset: { source: ctx.data.objects || [] },
  xAxis: { type: 'category' },
  yAxis: {},
  series: [
    {
      type: 'bar',
      showSymbol: false,
    },
  ],
}

return {
  dataset: {
    source: ctx.data.objects.reverse()
  },
  title: {
    text: "Monthly Sales Trend",
    subtext: "Last 12 Months",
    left: "center"
  },
  tooltip: {
    trigger: "axis",
    axisPointer: {
      type: "cross"
    }
  },
  legend: {
    data: ["Revenue", "Order Count", "Avg Order Value"],
    bottom: 0
  },
  grid: {
    left: "5%",
    right: "5%",
    bottom: "60",
    top: "80",
    containLabel: true
  },
  xAxis: {
    type: "category",
    boundaryGap: false,
    axisLabel: {
      rotate: 45
    }
  },
  yAxis: [
    {
      type: "value",
      name: "Amount(¥)",
      position: "left",
      axisLabel: {
        formatter: (value) => {
          return (value/10000).toFixed(0) + '0k';
        }
      }
    },
    {
      type: "value",
      name: "Order Count",
      position: "right"
    }
  ],
  series: [
    {
      name: "Revenue",
      type: "line",
      smooth: true,
      encode: {
        x: "month",
        y: "monthly_revenue"
      },
      areaStyle: {
        opacity: 0.3
      },
      itemStyle: {
        color: "#5470c6"
      }
    },
    {
      name: "Order Count",
      type: "bar",
      yAxisIndex: 1,
      encode: {
        x: "month",
        y: "order_count"
      },
      itemStyle: {
        color: "#91cc75",
        opacity: 0.6
      }
    },
    {
      name: "Avg Order Value",
      type: "line",
      encode: {
        x: "month",
        y: "avg_order_value"
      },
      itemStyle: {
        color: "#fac858"
      },
      lineStyle: {
        type: "dashed"
      }
    }
  ]
}