Ekklesia/surfaces/shell/tests/return-target.test.ts

// @vitest-environment node
import { describe, expect, it, vi } from "vitest";
import { dashboardBack } from "../src/browser/dashboard-back.js";
import { createMemoryHostHistory } from "../src/browser/host-history.js";
import { parseReturnTarget } from "../src/return-target.js";

describe("parseReturnTarget", () => {
  it("accepts a Dashboard page on this origin, as its canonical destination", () => {
    expect(parseReturnTarget("/")).toEqual({ kind: "overview" });
    expect(parseReturnTarget("/signage")).toEqual({ kind: "module", moduleId: "signage" });
    expect(parseReturnTarget("/signage/")).toEqual({ kind: "module", moduleId: "signage" });
    // Settings pages are Dashboard pages too (ADR 0061).
    expect(parseReturnTarget("/settings")).toEqual({ kind: "settings" });
    expect(parseReturnTarget("/settings/signage")).toEqual({
      kind: "module-settings",
      moduleId: "signage",
    });
  });

  it("refuses anything that is not a string, or is empty or enormous", () => {
    for (const value of [undefined, null, 42, {}, ["/signage"], "", `/${"a".repeat(3000)}`]) {
      expect(parseReturnTarget(value), JSON.stringify(value)).toBeUndefined();
    }
  });

  it("refuses every way of naming another origin", () => {
    for (const value of [
      "https://evil.example/signage",
      "http://localhost/signage",
      "//evil.example/signage",
      "/\\evil.example",
      "\\\\evil.example",
      "javascript:alert(1)",
      "data:text/html,hi",
      "  /signage",
      "/signage\n",
      "/sign\tage",
      "signage",
    ]) {
      expect(parseReturnTarget(value), value).toBeUndefined();
    }
  });

  it("refuses traversal and encoded separators that would normalize into something else", () => {
    for (const value of [
      "/signage/../settings",
      "/./signage",
      "/signage/%2e%2e/api",
      "/%2F%2Fevil.example",
      "/%5Cevil.example",
      "/signage%2Fx",
    ]) {
      expect(parseReturnTarget(value), value).toBeUndefined();
    }
  });

  it("refuses a query or fragment, and any path the Dashboard has no page for", () => {
    for (const value of [
      "/signage?x=1",
      "/signage#top",
      "/api/v1/principal",
      "/display/signage",
      "/settings/displays/add",
      "/signage/timelines",
    ]) {
      expect(parseReturnTarget(value), value).toBeUndefined();
    }
  });
});

describe("dashboardBack", () => {
  it("goes back to a validated origin when one was supplied", () => {
    const history = createMemoryHostHistory("/calendar");
    const back = dashboardBack(history, {
      fallback: { kind: "overview" },
      label: (destination) => (destination.kind === "module" ? "Back to Signage" : "Back"),
      returnTarget: "/signage",
    });

    expect(back.href).toBe("/signage");
    expect(back.label).toBe("Back to Signage");
    back.onBack();
    expect(history.entries).toEqual(["/calendar", "/signage"]);
  });

  it("falls back to the page's own parent when the target is missing or unsafe", () => {
    for (const returnTarget of [undefined, "https://evil.example/", "//evil.example", "/nope/x"]) {
      const history = createMemoryHostHistory("/calendar");
      const back = dashboardBack(history, {
        fallback: { kind: "overview" },
        returnTarget,
      });
      expect(back.href, String(returnTarget)).toBe("/");
      expect(back.label, String(returnTarget)).toBe("Back");
      back.onBack();
      expect(history.entries, String(returnTarget)).toEqual(["/calendar", "/"]);
    }
  });

  it("never leaves the Dashboard through the browser's own history", () => {
    const history = createMemoryHostHistory("/calendar");
    const go = vi.spyOn(history, "go");

    dashboardBack(history, { fallback: { kind: "overview" } }).onBack();

    expect(go).not.toHaveBeenCalled();
  });
});