import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from "node:fs";
import { tmpdir } from "node:os";
import path from "node:path";
import { afterEach, describe, expect, it } from "vitest";
import { type GitRunner, readGitCheckout } from "./git-checkout.js";

describe("readGitCheckout", () => {
  const roots: string[] = [];

  afterEach(() => {
    for (const root of roots.splice(0)) {
      rmSync(root, { recursive: true, force: true });
    }
  });

  function tempDir(prefix: string) {
    const root = mkdtempSync(path.join(tmpdir(), prefix));
    roots.push(root);
    return root;
  }

  it("returns absent status when .git is missing", async () => {
    const root = tempDir("git-checkout-absent-");
    await expect(readGitCheckout(root)).resolves.toEqual({
      present: false,
      remoteUrl: null,
      defaultBranch: null,
      headCommit: null,
      dirty: false,
      dirtyPaths: [],
    });
  });

  it("reads remote, branch, commit, and dirty paths from git metadata", async () => {
    const root = tempDir("git-checkout-present-");
    mkdirSync(path.join(root, ".git"));
    writeFileSync(path.join(root, "README.md"), "hello");

    const runner: GitRunner = async (args) => {
      if (args.join(" ") === "rev-parse HEAD") {
        return { ok: true, output: "abc123def456\n" };
      }
      if (args.join(" ") === "rev-parse --abbrev-ref HEAD") {
        return { ok: true, output: "main\n" };
      }
      if (args.join(" ") === "remote get-url origin") {
        return { ok: true, output: "https://github.com/example/demo.git\n" };
      }
      if (args.includes("status")) {
        return { ok: true, output: " M README.md\n" };
      }
      if (args.includes("ls-files")) {
        return { ok: true, output: "notes.txt\n" };
      }
      return { ok: false, output: "" };
    };

    await expect(readGitCheckout(root, runner)).resolves.toEqual({
      present: true,
      remoteUrl: "https://github.com/example/demo.git",
      defaultBranch: "main",
      headCommit: "abc123def456",
      dirty: true,
      dirtyPaths: ["README.md", "notes.txt"],
    });
  });
});