Add pie chart for asset/debt allocation in dashboard view (#666)

* Add pie chart for asset/debt allocation in dashboard view

* Fix lint issue

* Fix z-index issue with tooltip under pie chart

* Fix spacing of dashboard charts

app/helpers/accounts_helper.rb

@@ -7,6 +7,10 @@ module AccountsHelper
     class_mapping(accountable_type)[:text]
   end
 
+  def accountable_fill_class(accountable_type)
+    class_mapping(accountable_type)[:fill]
+  end
+
   def accountable_bg_class(accountable_type)
     class_mapping(accountable_type)[:bg]
   end
@@ -19,14 +23,14 @@ module AccountsHelper
 
   def class_mapping(accountable_type)
     {
-      "Account::Credit" => { text: "text-red-500", bg: "bg-red-500", bg_transparent: "bg-red-500/10" },
-      "Account::Loan" => { text: "text-fuchsia-500", bg: "bg-fuchsia-500", bg_transparent: "bg-fuchsia-500/10" },
-      "Account::OtherLiability" => { text: "text-gray-500", bg: "bg-gray-500", bg_transparent: "bg-gray-500/10" },
-      "Account::Depository" => { text: "text-violet-500", bg: "bg-violet-500", bg_transparent: "bg-violet-500/10" },
-      "Account::Investment" => { text: "text-blue-600", bg: "bg-blue-600", bg_transparent: "bg-blue-600/10" },
-      "Account::OtherAsset" => { text: "text-green-500", bg: "bg-green-500", bg_transparent: "bg-green-500/10" },
-      "Account::Property" => { text: "text-cyan-500", bg: "bg-cyan-500", bg_transparent: "bg-cyan-500/10" },
-      "Account::Vehicle" => { text: "text-pink-500", bg: "bg-pink-500", bg_transparent: "bg-pink-500/10" }
-    }.fetch(accountable_type, { text: "text-gray-500", bg: "bg-gray-500", bg_transparent: "bg-gray-500/10" })
+      "Account::Credit" => { text: "text-red-500", bg: "bg-red-500", bg_transparent: "bg-red-500/10", fill: "fill-red-500" },
+      "Account::Loan" => { text: "text-fuchsia-500", bg: "bg-fuchsia-500", bg_transparent: "bg-fuchsia-500/10", fill: "fill-fuchsia-500" },
+      "Account::OtherLiability" => { text: "text-gray-500", bg: "bg-gray-500", bg_transparent: "bg-gray-500/10", fill: "fill-gray-500" },
+      "Account::Depository" => { text: "text-violet-500", bg: "bg-violet-500", bg_transparent: "bg-violet-500/10", fill: "fill-violet-500" },
+      "Account::Investment" => { text: "text-blue-600", bg: "bg-blue-600", bg_transparent: "bg-blue-600/10", fill: "fill-blue-600" },
+      "Account::OtherAsset" => { text: "text-green-500", bg: "bg-green-500", bg_transparent: "bg-green-500/10", fill: "fill-green-500" },
+      "Account::Property" => { text: "text-cyan-500", bg: "bg-cyan-500", bg_transparent: "bg-cyan-500/10", fill: "fill-cyan-500" },
+      "Account::Vehicle" => { text: "text-pink-500", bg: "bg-pink-500", bg_transparent: "bg-pink-500/10", fill: "fill-pink-500" }
+    }.fetch(accountable_type, { text: "text-gray-500", bg: "bg-gray-500", bg_transparent: "bg-gray-500/10", fill: "fill-gray-500" })
   end
 end

app/helpers/value_groups_helper.rb

@@ -0,0 +1,17 @@
+module ValueGroupsHelper
+  def value_group_pie_data(value_group)
+    value_group.children
+      .map do |child|
+        {
+          label: to_accountable_title(Accountable.from_type(child.name)),
+          percent_of_total: child.percent_of_total.round(1).to_f,
+          value: child.sum.amount.to_f,
+          currency: child.sum.currency.iso_code,
+          bg_color: accountable_bg_class(child.name),
+          fill_color: accountable_fill_class(child.name)
+        }
+      end
+      .filter { |child| child[:value] > 0 }
+      .to_json
+  end
+end

app/javascript/controllers/pie_chart_controller.js

@@ -0,0 +1,176 @@
+import { Controller } from "@hotwired/stimulus";
+import * as d3 from "d3";
+
+// Connects to data-controller="pie-chart"
+export default class extends Controller {
+  static values = {
+    data: Array,
+    label: String,
+  };
+
+  #d3SvgMemo = null;
+  #d3GroupMemo = null;
+  #d3ContentMemo = null;
+  #d3ViewboxWidth = 200;
+  #d3ViewboxHeight = 200;
+
+  connect() {
+    this.#draw();
+    document.addEventListener("turbo:load", this.#redraw);
+  }
+
+  disconnect() {
+    this.#teardown();
+    document.removeEventListener("turbo:load", this.#redraw);
+  }
+
+  #redraw = () => {
+    this.#teardown();
+    this.#draw();
+  };
+
+  #teardown() {
+    this.#d3SvgMemo = null;
+    this.#d3GroupMemo = null;
+    this.#d3ContentMemo = null;
+    this.#d3Container.selectAll("*").remove();
+  }
+
+  #draw() {
+    this.#d3Container.attr("class", "relative");
+    this.#d3Content.html(this.#contentSummaryTemplate(this.dataValue));
+
+    const pie = d3
+      .pie()
+      .value((d) => d.percent_of_total)
+      .padAngle(0.06);
+
+    const arc = d3
+      .arc()
+      .innerRadius(this.#radius - 8)
+      .outerRadius(this.#radius)
+      .cornerRadius(2);
+
+    const arcs = this.#d3Group
+      .selectAll("arc")
+      .data(pie(this.dataValue))
+      .enter()
+      .append("g")
+      .attr("class", "arc");
+
+    const paths = arcs
+      .append("path")
+      .attr("class", (d) => d.data.fill_color)
+      .attr("d", arc);
+
+    paths
+      .on("mouseover", (event) => {
+        this.#d3Svg.selectAll(".arc path").attr("class", "fill-gray-200");
+        d3.select(event.target).attr("class", (d) => d.data.fill_color);
+        this.#d3ContentMemo.html(
+          this.#contentDetailTemplate(d3.select(event.target).datum().data),
+        );
+      })
+      .on("mouseout", () => {
+        this.#d3Svg
+          .selectAll(".arc path")
+          .attr("class", (d) => d.data.fill_color);
+        this.#d3ContentMemo.html(this.#contentSummaryTemplate(this.dataValue));
+      });
+  }
+
+  #contentSummaryTemplate(data) {
+    const total = data.reduce((acc, cur) => acc + cur.value, 0);
+    const currency = data[0].currency;
+
+    return `${this.#currencyValue({
+      value: total,
+      currency,
+    })} <span class="text-xs">${this.labelValue}</span>`;
+  }
+
+  #contentDetailTemplate(datum) {
+    return `
+      <span>${this.#currencyValue(datum)}</span>
+      <div class="flex flex-row text-xs gap-2 items-center">
+      <div class="w-[10px] h-[10px] rounded-full ${datum.bg_color}"></div>
+        <span>${datum.label}</span>
+        <span>${datum.percent_of_total}%</span>
+      </div>
+    `;
+  }
+
+  #currencyValue(datum) {
+    const formattedValue = Intl.NumberFormat(undefined, {
+      style: "currency",
+      currency: datum.currency,
+      currencyDisplay: "narrowSymbol",
+    }).format(datum.value);
+
+    const firstDigitIndex = formattedValue.search(/\d/);
+    const currencyPrefix = formattedValue.substring(0, firstDigitIndex);
+    const mainPart = formattedValue.substring(firstDigitIndex);
+    const [integerPart, fractionalPart] = mainPart.split(".");
+
+    return `<p class="text-gray-500 -space-x-0.5">${currencyPrefix}<span class="text-xl text-gray-900 font-medium">${integerPart}</span>.${fractionalPart}</p>`;
+  }
+
+  get #radius() {
+    return Math.min(this.#d3ViewboxWidth, this.#d3ViewboxHeight) / 2;
+  }
+
+  get #d3Container() {
+    return d3.select(this.element);
+  }
+
+  get #d3Svg() {
+    if (this.#d3SvgMemo) {
+      return this.#d3SvgMemo;
+    } else {
+      return (this.#d3SvgMemo = this.#createMainSvg());
+    }
+  }
+
+  get #d3Group() {
+    if (this.#d3GroupMemo) {
+      return this.#d3GroupMemo;
+    } else {
+      return (this.#d3GroupMemo = this.#createMainGroup());
+    }
+  }
+
+  get #d3Content() {
+    if (this.#d3ContentMemo) {
+      return this.#d3ContentMemo;
+    } else {
+      return (this.#d3ContentMemo = this.#createContent());
+    }
+  }
+
+  #createMainSvg() {
+    return this.#d3Container
+      .append("svg")
+      .attr("width", "100%")
+      .attr("class", "relative aspect-1")
+      .attr("viewBox", [0, 0, this.#d3ViewboxWidth, this.#d3ViewboxHeight]);
+  }
+
+  #createMainGroup() {
+    return this.#d3Svg
+      .append("g")
+      .attr(
+        "transform",
+        `translate(${this.#d3ViewboxWidth / 2},${this.#d3ViewboxHeight / 2})`,
+      );
+  }
+
+  #createContent() {
+    this.#d3ContentMemo = this.#d3Container
+      .append("div")
+      .attr(
+        "class",
+        "absolute inset-0 w-full text-center flex flex-col items-center justify-center",
+      );
+    return this.#d3ContentMemo;
+  }
+}

app/javascript/controllers/time_series_chart_controller.js

@@ -326,6 +326,7 @@ export default class extends Controller {
         this.#d3Tooltip
           .html(this.#tooltipTemplate(d))
           .style("opacity", 1)
+          .style("z-index", 999)
           .style("left", adjustedX + "px")
           .style("top", event.pageY - 10 + "px")
       })

app/views/pages/dashboard.html.erb

@@ -11,7 +11,7 @@
     <% end %>
   </header>
   <section class="flex gap-4">
-    <div class="bg-white border border-alpha-black-25 shadow-xs rounded-xl w-3/4 min-h-48">
+    <div class="bg-white border border-alpha-black-25 shadow-xs rounded-xl w-3/4 min-h-48 flex flex-col">
       <div class="flex justify-between p-4">
         <div>
           <%= render partial: "shared/value_heading", locals: {
@@ -28,7 +28,7 @@
       <%= render partial: "pages/dashboard/net_worth_chart", locals: { series: @net_worth_series } %>
     </div>
     <div class="bg-white p-4 border border-alpha-black-25 shadow-xs rounded-xl w-1/4">
-      <%= render partial: "pages/dashboard/allocation_chart" %>
+      <%= render partial: "pages/dashboard/allocation_chart", locals: { account_groups: @account_groups } %>
     </div>
   </section>
   <section class="grid grid-cols-2 gap-4">

app/views/pages/dashboard/_allocation_chart.html.erb

@@ -1,3 +1,4 @@
+<%# locals: (account_groups:) -%>
 <div data-controller="tabs" data-tabs-active-class="bg-white border-alpha-black-25 shadow-xs text-gray-900" data-tabs-default-tab-value="asset-tab">
   <div class="bg-gray-25 rounded-lg p-1 flex gap-1 text-sm text-gray-500 font-medium">
     <button data-id="asset-tab" class="w-1/2 px-2 py-1 rounded-md border border-transparent" data-tabs-target="btn" data-action="tabs#select"><%= t(".assets") %></button>
@@ -5,13 +6,23 @@
   </div>
   <div>
     <div data-tabs-target="tab" id="asset-tab" class="space-y-6">
-      <div class="text-gray-500 flex items-center justify-center py-12">
-        <p>Coming soon...</p>
+      <div class="text-gray-500 flex items-center justify-center py-6">
+        <div
+          data-controller="pie-chart"
+          class="w-full aspect-1"
+          data-pie-chart-label-value="Total Assets"
+          data-pie-chart-data-value="<%= value_group_pie_data(account_groups[:assets]) %>">
+        </div>
       </div>
     </div>
     <div data-tabs-target="tab" id="liability-tab" class="space-y-6 hidden">
-      <div class="text-gray-500 flex items-center justify-center py-12">
-        <p>Coming soon...</p>
+      <div class="text-gray-500 flex items-center justify-center py-6">
+        <div
+          data-controller="pie-chart"
+          class="w-full aspect-1"
+          data-pie-chart-label-value="Total Debts"
+          data-pie-chart-data-value="<%= value_group_pie_data(account_groups[:liabilities]) %>">
+        </div>
       </div>
     </div>
   </div>

app/views/pages/dashboard/_net_worth_chart.html.erb

@@ -2,7 +2,7 @@
 <% if series %>
   <div
     id="netWorthChart"
-    class="w-full h-full"
+    class="w-full flex-1 min-h-52"
     data-controller="time-series-chart"
     data-time-series-chart-data-value="<%= series.to_json %>"></div>
 <% else %>