feat(ui): add AMS-vs-human contributor-mix maintainer dashboard panel

apps/loopover-ui/public/openapi.json

@@ -13971,6 +13971,91 @@
           "scope_cap_files",
           "scope_cap_lines"
         ]
+      },
+      "AmsMinerCohortComparison": {
+        "type": "object",
+        "properties": {
+          "present": {
+            "type": "boolean"
+          },
+          "windowDays": {
+            "type": "number"
+          },
+          "totalSubmitterCount": {
+            "type": "number"
+          },
+          "checkedSubmitterCount": {
+            "type": "number"
+          },
+          "amsCohort": {
+            "type": "object",
+            "properties": {
+              "submitterCount": {
+                "type": "number"
+              },
+              "prVolume": {
+                "type": "number"
+              },
+              "acceptanceRate": {
+                "type": "number",
+                "nullable": true
+              },
+              "avgReviewCycleCount": {
+                "type": "number",
+                "nullable": true
+              },
+              "avgTimeToMergeMs": {
+                "type": "number",
+                "nullable": true
+              }
+            },
+            "required": [
+              "submitterCount",
+              "prVolume",
+              "acceptanceRate",
+              "avgReviewCycleCount",
+              "avgTimeToMergeMs"
+            ]
+          },
+          "humanCohort": {
+            "type": "object",
+            "properties": {
+              "submitterCount": {
+                "type": "number"
+              },
+              "prVolume": {
+                "type": "number"
+              },
+              "acceptanceRate": {
+                "type": "number",
+                "nullable": true
+              },
+              "avgReviewCycleCount": {
+                "type": "number",
+                "nullable": true
+              },
+              "avgTimeToMergeMs": {
+                "type": "number",
+                "nullable": true
+              }
+            },
+            "required": [
+              "submitterCount",
+              "prVolume",
+              "acceptanceRate",
+              "avgReviewCycleCount",
+              "avgTimeToMergeMs"
+            ]
+          }
+        },
+        "required": [
+          "present",
+          "windowDays",
+          "totalSubmitterCount",
+          "checkedSubmitterCount",
+          "amsCohort",
+          "humanCohort"
+        ]
       }
     },
     "parameters": {},

apps/loopover-ui/src/components/site/app-panels/ams-miner-cohort-card.test.tsx

@@ -0,0 +1,142 @@
+import { render, screen, fireEvent, waitFor } from "@testing-library/react";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+// Mock the API layer so the component never touches the network.
+const { apiFetch } = vi.hoisted(() => ({ apiFetch: vi.fn() }));
+vi.mock("@/lib/api/request", () => ({ apiFetch: (...args: unknown[]) => apiFetch(...args) }));
+vi.mock("@/lib/api/origin", () => ({ getApiOrigin: () => "https://api.test" }));
+
+import { AmsMinerCohortCard } from "@/components/site/app-panels/ams-miner-cohort-card";
+
+const REVIEWABILITY = [{ pr: "acme/widgets#1" }];
+
+const POPULATED_COMPARISON = {
+  present: true,
+  windowDays: 90,
+  totalSubmitterCount: 5,
+  checkedSubmitterCount: 5,
+  amsCohort: {
+    submitterCount: 2,
+    prVolume: 20,
+    acceptanceRate: 0.8,
+    avgReviewCycleCount: 1.5,
+    avgTimeToMergeMs: 3_600_000,
+  },
+  humanCohort: {
+    submitterCount: 3,
+    prVolume: 9,
+    acceptanceRate: 0.5,
+    avgReviewCycleCount: 2.5,
+    avgTimeToMergeMs: 172_800_000,
+  },
+};
+
+describe("AmsMinerCohortCard", () => {
+  beforeEach(() => {
+    apiFetch.mockReset();
+  });
+
+  it("shows a loading state, then renders both cohorts on load", async () => {
+    apiFetch.mockResolvedValue({ ok: true, data: POPULATED_COMPARISON });
+    render(<AmsMinerCohortCard reviewability={REVIEWABILITY} />);
+
+    expect(screen.getByText(/Loading AMS contributor mix/i)).toBeTruthy();
+    await waitFor(() => expect(screen.getByText("AMS miners")).toBeTruthy());
+    expect(screen.getByText("Other contributors")).toBeTruthy();
+    expect(screen.getByText(/Window: 90 days · checked 5 of/i)).toBeTruthy();
+    expect(apiFetch).toHaveBeenCalledWith(
+      expect.stringContaining("/v1/repos/acme/widgets/ams-miner-cohort"),
+      expect.objectContaining({ label: "AMS miner cohort comparison" }),
+    );
+  });
+
+  it("renders the AMS cohort's acceptance rate, review-cycle count, and time-to-merge", async () => {
+    apiFetch.mockResolvedValue({ ok: true, data: POPULATED_COMPARISON });
+    render(<AmsMinerCohortCard reviewability={REVIEWABILITY} />);
+    await waitFor(() => expect(screen.getByText("AMS miners")).toBeTruthy());
+    expect(screen.getByText("80%")).toBeTruthy();
+    expect(screen.getByText("1.5")).toBeTruthy();
+    expect(screen.getByText("1.0h")).toBeTruthy();
+  });
+
+  it("renders days for a time-to-merge at or beyond 24 hours", async () => {
+    apiFetch.mockResolvedValue({ ok: true, data: POPULATED_COMPARISON });
+    render(<AmsMinerCohortCard reviewability={REVIEWABILITY} />);
+    await waitFor(() => expect(screen.getByText("Other contributors")).toBeTruthy());
+    expect(screen.getByText("2.0d")).toBeTruthy();
+  });
+
+  it("renders an empty state (never an error) when the API reports present: false", async () => {
+    apiFetch.mockResolvedValue({
+      ok: true,
+      data: {
+        present: false,
+        windowDays: 0,
+        totalSubmitterCount: 0,
+        checkedSubmitterCount: 0,
+        amsCohort: {
+          submitterCount: 0,
+          prVolume: 0,
+          acceptanceRate: null,
+          avgReviewCycleCount: null,
+          avgTimeToMergeMs: null,
+        },
+        humanCohort: {
+          submitterCount: 0,
+          prVolume: 0,
+          acceptanceRate: null,
+          avgReviewCycleCount: null,
+          avgTimeToMergeMs: null,
+        },
+      },
+    });
+    render(<AmsMinerCohortCard reviewability={REVIEWABILITY} />);
+    await waitFor(() => expect(screen.getByText(/No identifiable AMS activity yet/i)).toBeTruthy());
+  });
+
+  it("renders — for a null acceptanceRate/avgTimeToMergeMs rather than fabricating a number", async () => {
+    apiFetch.mockResolvedValue({
+      ok: true,
+      data: {
+        ...POPULATED_COMPARISON,
+        amsCohort: {
+          submitterCount: 1,
+          prVolume: 1,
+          acceptanceRate: null,
+          avgReviewCycleCount: null,
+          avgTimeToMergeMs: null,
+        },
+      },
+    });
+    render(<AmsMinerCohortCard reviewability={REVIEWABILITY} />);
+    await waitFor(() => expect(screen.getByText("AMS miners")).toBeTruthy());
+    expect(screen.getAllByText("—").length).toBeGreaterThan(0);
+  });
+
+  it("renders an error state with the failure message when the comparison fails to load", async () => {
+    apiFetch.mockResolvedValue({ ok: false, message: "503 Service Unavailable" });
+    render(<AmsMinerCohortCard reviewability={REVIEWABILITY} />);
+
+    await waitFor(() =>
+      expect(screen.getByText(/Couldn't load the AMS contributor mix/i)).toBeTruthy(),
+    );
+    expect(screen.getByText("503 Service Unavailable")).toBeTruthy();
+  });
+
+  it("falls back to a manual owner/repo entry when no repos are registered yet", () => {
+    render(<AmsMinerCohortCard reviewability={[]} />);
+    expect(screen.getByText(/No registered repositories detected yet/i)).toBeTruthy();
+    expect(screen.getByText(/Enter an installed repository to compare cohorts\./i)).toBeTruthy();
+  });
+
+  it("shows the 'view unavailable' copy for a typed repo string that doesn't parse as owner\\/repo", async () => {
+    apiFetch.mockResolvedValue({ ok: true, data: POPULATED_COMPARISON });
+    render(<AmsMinerCohortCard reviewability={REVIEWABILITY} />);
+    await waitFor(() => expect(screen.getByText("AMS miners")).toBeTruthy());
+
+    fireEvent.change(screen.getByPlaceholderText("owner/repo"), {
+      target: { value: "not-a-valid-slug" },
+    });
+    expect(screen.getByText(/This view is unavailable for this repository\./i)).toBeTruthy();
+  });
+});