import { afterAll, beforeAll, expect, test } from "vitest";
import { execFileSync } from "node:child_process";
import { mkdtempSync, mkdirSync, rmSync, readFileSync } from "node:fs";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { ChildProcessGitClient } from "./git";

let root: string, bare: string, base: string;

beforeAll(() => {
  root = mkdtempSync(join(tmpdir(), "jp-git-"));
  bare = join(root, "remote.git");
  base = join(root, "work");
  mkdirSync(bare); mkdirSync(base);
  execFileSync("git", ["init", "--bare", "-b", "main", bare]);
  // seed an initial commit so the branch exists
  const seed = join(root, "seed");
  mkdirSync(seed);
  execFileSync("git", ["init", "-b", "main", seed]);
  execFileSync("git", ["-C", seed, "config", "user.email", "t@t"]);
  execFileSync("git", ["-C", seed, "config", "user.name", "t"]);
  execFileSync("git", ["-C", seed, "commit", "--allow-empty", "-m", "init"]);
  execFileSync("git", ["-C", seed, "remote", "add", "origin", bare]);
  execFileSync("git", ["-C", seed, "push", "origin", "main"]);
});

afterAll(() => rmSync(root, { recursive: true, force: true }));

test("clone, write, commit, push lands files in the remote", async () => {
  const client = new ChildProcessGitClient({ baseDir: base });
  await client.syncClone({ url: bare, branch: "main" });
  await client.writeFiles([
    { repoPath: "_posts/2026-06-19-hi.md", data: "---\nlayout: post\n---\n\nHi\n" },
    { repoPath: "assets/img/hi.png", data: Buffer.from([1, 2, 3]) },
  ]);
  await client.commitAndPush({ message: "Publish: Hi", branch: "main", authorName: "t", authorEmail: "t@t" });

  const verify = join(root, "verify");
  execFileSync("git", ["clone", bare, verify]);
  expect(readFileSync(join(verify, "_posts/2026-06-19-hi.md"), "utf8")).toContain("Hi");
  expect(Array.from(readFileSync(join(verify, "assets/img/hi.png")))).toEqual([1, 2, 3]);
});

test("second sync resets cleanly (fetch+reset path)", async () => {
  const client = new ChildProcessGitClient({ baseDir: base });
  await client.syncClone({ url: bare, branch: "main" });
  await client.writeFiles([{ repoPath: "_posts/second.md", data: "x" }]);
  // Pass an explicit author so the test does not depend on an ambient git
  // identity (a bare CI runner has none and `git commit` would fail).
  await client.commitAndPush({ message: "second", branch: "main", authorName: "t", authorEmail: "t@t" });
  const verify = join(root, "verify2");
  execFileSync("git", ["clone", bare, verify]);
  expect(readFileSync(join(verify, "_posts/second.md"), "utf8")).toBe("x");
});

test("commitAndPush rejects with diagnostic error when nothing is staged", async () => {
  // Use a fresh base dir so we get a clean clone
  const base2 = join(root, "work2");
  mkdirSync(base2, { recursive: true });
  const client = new ChildProcessGitClient({ baseDir: base2 });
  // Clone and write a file, then commit it
  await client.syncClone({ url: bare, branch: "main" });
  await client.writeFiles([{ repoPath: "_posts/no-change.md", data: "same content" }]);
  await client.commitAndPush({ message: "initial no-change", branch: "main", authorName: "t", authorEmail: "t@t" });

  // Now sync again — tree now matches origin, re-writing the same content stages nothing
  const client2 = new ChildProcessGitClient({ baseDir: base2 });
  await client2.syncClone({ url: bare, branch: "main" });
  await client2.writeFiles([{ repoPath: "_posts/no-change.md", data: "same content" }]);
  await expect(
    client2.commitAndPush({ message: "noop", branch: "main", authorName: "t", authorEmail: "t@t" })
  ).rejects.toThrow(/no changes to publish/i);
});