feat: add token breakdown helpers

lib/token-breakdown.test.ts

@@ -0,0 +1,66 @@
+import { describe, expect, test } from "bun:test";
+import {
+  getPrimaryModelNames,
+  getSharePercent,
+  getTokenDisplayName,
+  getTokenRowKey,
+  shouldShowTokenTab,
+  sortTokenBreakdown,
+} from "./token-breakdown";
+
+describe("token breakdown helpers", () => {
+  const rows = [
+    {
+      name: "beta",
+      calls: 2,
+      total_tokens: 100,
+      quota: 500,
+      models: [{ name: "gpt-4o", calls: 1, total_tokens: 70, quota: 300 }],
+    },
+    {
+      name: "alpha",
+      calls: 5,
+      total_tokens: 300,
+      quota: 300,
+      models: [{ name: "claude-sonnet-4", calls: 1, total_tokens: 200, quota: 200 }],
+    },
+  ];
+
+  test("sorts token rows without mutating nested model data", () => {
+    const sorted = sortTokenBreakdown(rows, "total_tokens", false);
+
+    expect(sorted.map((row) => row.name)).toEqual(["alpha", "beta"]);
+    expect(sorted[0].models[0].name).toBe("claude-sonnet-4");
+    expect(rows.map((row) => row.name)).toEqual(["beta", "alpha"]);
+  });
+
+  test("uses a localized label for unnamed tokens", () => {
+    expect(getTokenDisplayName("", "未命名令牌")).toBe("未命名令牌");
+    expect(getTokenDisplayName("prod-key", "未命名令牌")).toBe("prod-key");
+  });
+
+  test("keeps unnamed token row keys stable", () => {
+    expect(getTokenRowKey("")).toBe("__unnamed_token__");
+    expect(getTokenRowKey("prod-key")).toBe("prod-key");
+  });
+
+  test("shows the token tab only for user details", () => {
+    expect(shouldShowTokenTab("user")).toBe(true);
+    expect(shouldShowTokenTab("model")).toBe(false);
+    expect(shouldShowTokenTab("channel")).toBe(false);
+  });
+
+  test("calculates share percentages and handles empty totals", () => {
+    expect(getSharePercent(25, 100)).toBe(25);
+    expect(getSharePercent(25, 0)).toBe(0);
+  });
+
+  test("formats a compact primary model preview", () => {
+    expect(getPrimaryModelNames([
+      { name: "a", calls: 1, total_tokens: 1, quota: 1 },
+      { name: "b", calls: 1, total_tokens: 1, quota: 1 },
+      { name: "c", calls: 1, total_tokens: 1, quota: 1 },
+      { name: "d", calls: 1, total_tokens: 1, quota: 1 },
+    ])).toBe("a, b, c");
+  });
+});