import { mkdtemp, rm } from "node:fs/promises";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { describe, expect, it } from "vitest";
import { RECENT_CAP, addRecent, loadRecent, saveRecent } from "../src/recent.js";
import type { EditorRecentEntry } from "../src/ipc.js";

function entry(root: string, name = "p"): EditorRecentEntry {
  return { root, name };
}

describe("addRecent", () => {
  it("prepends new entries and dedupes by root", () => {
    const base = [entry("/a"), entry("/b")];
    const next = addRecent(base, entry("/b", "b2"));
    expect(next.map((e) => e.root)).toEqual(["/b", "/a"]);
    expect(next[0]?.name).toBe("b2");
  });

  it("caps the list at RECENT_CAP", () => {
    let list: EditorRecentEntry[] = [];
    for (let i = 0; i < RECENT_CAP + 3; i++) list = addRecent(list, entry(`/p${i}`));
    expect(list.length).toBe(RECENT_CAP);
    expect(list[0]?.root).toBe(`/p${RECENT_CAP + 2}`);
  });
});

describe("recent persistence", () => {
  it("roundtrips through a json file", async () => {
    const dir = await mkdtemp(join(tmpdir(), "editor-recent-"));
    try {
      const file = join(dir, "recent.json");
      const entries = [entry("/a", "A"), entry("/b", "B")];
      await saveRecent(file, entries);
      expect(await loadRecent(file)).toEqual(entries);
    } finally {
      await rm(dir, { recursive: true, force: true });
    }
  });

  it("returns [] for a missing file", async () => {
    const dir = await mkdtemp(join(tmpdir(), "editor-recent-"));
    try {
      expect(await loadRecent(join(dir, "nope.json"))).toEqual([]);
    } finally {
      await rm(dir, { recursive: true, force: true });
    }
  });

  it("returns [] for corrupt json and drops invalid entries", async () => {
    const dir = await mkdtemp(join(tmpdir(), "editor-recent-"));
    try {
      const corrupt = join(dir, "corrupt.json");
      const { writeFile } = await import("node:fs/promises");
      await writeFile(corrupt, "{ not json", "utf8");
      expect(await loadRecent(corrupt)).toEqual([]);

      const mixed = join(dir, "mixed.json");
      await writeFile(mixed, JSON.stringify([{ root: "/ok", name: "Ok" }, { root: 42 }, "junk"]), "utf8");
      expect(await loadRecent(mixed)).toEqual([{ root: "/ok", name: "Ok" }]);
    } finally {
      await rm(dir, { recursive: true, force: true });
    }
  });
});