import assert from "node:assert/strict";
import { test } from "node:test";
import { createServer } from "node:http";

// Fixtures follow Gitea's GitTreeResponse as its API documents it (swagger: sha, url, tree[{path, mode, type, size,
// sha, url}], truncated, page, total_count) and as the forge answers GET /repos/{o}/{r}/git/trees/{sha}; the entry
// fields are those, with sha values written out. The live capture (1234/AC6): GET
// /repos/novox/mesh-delivery/git/trees/7f61817 (non-recursive) answered the COMMIT's sha at the top, not the root
// tree's; the root tree is computed from the root's own entries, as git does.
import { createHash } from "node:crypto";

const COMMIT = "c".repeat(40);
const h = (c: string) => c.repeat(40);
const entry = (path: string, type: "tree" | "blob", sha: string) => ({
  path, mode: type === "tree" ? "040000" : "100644", type, size: type === "tree" ? 0 : 12, sha, url: `u/${sha}`,
});
const LISTING = [
  entry("README.md", "blob", h("1")),
  entry("module.json", "blob", h("2")),
  entry("modules", "tree", h("3")),
  entry("modules/a", "tree", h("4")),
  entry("modules/a/module.json", "blob", h("5")),
  entry("modules/a/main.go", "blob", h("6")),
  entry("modules/b", "tree", h("7")),
  entry("modules/b/c", "tree", h("8")),
  entry("modules/b/c/module.json", "blob", h("9")),
  entry("modules/d", "tree", h("a")),
  entry("modules/d/notes.md", "blob", h("b")),
];

/** git's own hash of a tree from its entries (an independent restatement for the fixtures): mode without leading zero. */
function gitTree(es: { path: string; type: string; sha: string; mode: string }[]): string {
  const ordered = es.map((e) => ({ ...e, key: e.path + (e.type === "tree" ? "/" : "") })).sort((a, b) => Buffer.compare(Buffer.from(a.key), Buffer.from(b.key)));
  const body = Buffer.concat(ordered.map((e) => Buffer.concat([Buffer.from(`${e.mode.replace(/^0+/, "")} ${e.path}\0`), Buffer.from(e.sha, "hex")])));
  return createHash("sha1").update(Buffer.concat([Buffer.from(`tree ${body.length}\0`), body])).digest("hex");
}
const ROOT = gitTree(LISTING.filter((e) => !e.path.includes("/")));

async function serve(pages: any[]) {
  const { GiteaClient } = await import("../client.ts");
  const asked: string[] = [];
  const server = createServer((req, res) => {
    asked.push(req.url ?? "");
    const url = new URL(req.url ?? "", "http://x");
    if (url.pathname !== `/api/v1/repos/novox/hq/git/trees/${COMMIT}` || url.searchParams.get("recursive") !== "true") {
      res.statusCode = 404;
      return res.end("{}");
    }
    const page = Number(url.searchParams.get("page") ?? 1);
    res.end(JSON.stringify(pages[page - 1] ?? { sha: COMMIT, tree: [], truncated: false, page, total_count: 0 }));
  });
  await new Promise<void>((r) => server.listen(0, r));
  const client = new GiteaClient(`http://127.0.0.1:${(server.address() as any).port}`, "t");
  return { client, server, asked };
}

test("a commit's trees: the root and the tree of each directory holding a module.json", async () => {
  // 1234/AC1 and 1234/AC4
  const { client, server } = await serve([{ sha: COMMIT, url: "u", tree: LISTING, truncated: false, page: 1, total_count: LISTING.length }]);
  try {
    const got = await client.commitTrees("novox", "hq", COMMIT);
    assert.deepEqual(got, { root: ROOT, trees: { "": ROOT, "modules/a": h("4"), "modules/b/c": h("8") } });
  } finally {
    server.close();
  }
});

test("a listing the forge pages is read page by page", async () => {
  // 1234/AC1
  const { client, server, asked } = await serve([
    { sha: COMMIT, tree: LISTING.slice(0, 5), truncated: true, page: 1, total_count: LISTING.length },
    { sha: COMMIT, tree: LISTING.slice(5, 9), truncated: true, page: 2, total_count: LISTING.length },
    { sha: COMMIT, tree: LISTING.slice(9), truncated: false, page: 3, total_count: LISTING.length },
  ]);
  try {
    const got = await client.commitTrees("novox", "hq", COMMIT);
    assert.deepEqual(got.trees, { "": ROOT, "modules/a": h("4"), "modules/b/c": h("8") });
    assert.equal(asked.length, 3, `asked ${asked.join(" ")}`);
  } finally {
    server.close();
  }
});

test("a listing the forge says is cut fails, naming the repository and the commit, and answers no trees", async () => {
  // 1234/AC2
  const { client, server } = await serve([{ sha: COMMIT, tree: LISTING, truncated: true, page: 1, total_count: LISTING.length }]);
  try {
    await assert.rejects(client.commitTrees("novox", "hq", COMMIT), (err: Error) => {
      assert.match(err.message, /novox\/hq/);
      assert.ok(err.message.includes(COMMIT), err.message);
      assert.match(err.message, /cut/);
      return true;
    });
  } finally {
    server.close();
  }
});

test("a sha that is not a full commit, or no owner or repo, is refused before the forge is asked", async () => {
  // 1234/AC3
  const { getGiteaTools } = await import("../tools/index.ts");
  const { client, server, asked } = await serve([]);
  try {
    const tool = getGiteaTools(client).find((t) => t.name === "gitea_commit_trees")!;
    assert.ok(tool, "the tool is listed");
    for (const args of [
      { owner: "novox", repo: "hq", sha: "abc1234" },
      { owner: "novox", repo: "hq", sha: "main" },
      { owner: "novox", repo: "hq", sha: "" },
      { owner: "novox", repo: "hq", sha: "c".repeat(41) },
      { owner: "", repo: "hq", sha: COMMIT },
      { owner: "novox", repo: " ", sha: COMMIT },
    ]) await assert.rejects(tool.run(args as any), /./, JSON.stringify(args));
    assert.equal(asked.length, 0, `the forge was asked ${asked.join(" ")}`);
  } finally {
    server.close();
  }
});

test("gitea_open_pulls says each pull request's head branch beside its head sha", async () => {
  // 1234/AC5
  const { GiteaClient } = await import("../client.ts");
  const server = createServer((req, res) => {
    const url = req.url ?? "";
    const send = (v: unknown) => res.end(JSON.stringify(v));
    if (url.startsWith("/api/v1/repos/issues/search")) {
      return send(url.includes("page=1") ? [{ number: 7, repository: { owner: "novox", name: "hq", full_name: "novox/hq" } }] : []);
    }
    if (url.startsWith("/api/v1/repos/novox/hq/pulls/7")) {
      return send({ number: 7, state: "open", base: { ref: "main" }, head: { ref: "feat/x", sha: "aaa1111" }, html_url: "h" });
    }
    if (url.includes("/branch_protections")) { res.statusCode = 403; return res.end("{}"); }
    if (url.startsWith("/api/v1/repos/novox/hq/branches/main")) return send({ name: "main" });
    if (url.includes("/commits/aaa1111/status")) return send({ statuses: [] });
    res.statusCode = 404;
    res.end("{}");
  });
  await new Promise<void>((r) => server.listen(0, r));
  const client = new GiteaClient(`http://127.0.0.1:${(server.address() as any).port}`, "t");
  try {
    const [p] = await client.openPulls();
    assert.deepEqual(p, { owner: "novox", repo: "hq", number: 7, base: "main", head: "feat/x", head_sha: "aaa1111", html_url: "h",
      required: [], statuses: [], checks: {}, labels: [] });
  } finally {
    server.close();
  }
});

test("the root tree is git's hash of the root's own entries, never the listing's top sha (the commit's)", async () => {
  // 1234/AC6, from the live capture named in the header: novox/mesh-delivery at 7f61817.
  const commit = "7f618177d6773d8d2d2b9e0b10e13b85ec700c59";
  const listing = [
    entry("README.md", "blob", "a087d22cbcbecce42256315671ff7e4d6ca85a7c"),
    entry("merge-check.sh", "blob", "c4ef9a3dd6390b0edde7e4137095553897cecfb0"),
    entry("modules", "tree", "31c0abb312ee6ce4693a7aacdd8b3fba871d6cf3"),
    entry("modules/x", "tree", h("d")),
    entry("modules/x/module.json", "blob", h("e")),
  ];
  const { GiteaClient } = await import("../client.ts");
  const server = createServer((req, res) => {
    res.end(JSON.stringify(new URL(req.url ?? "", "http://x").pathname.endsWith(`/git/trees/${commit}`)
      ? { sha: commit, tree: listing, truncated: false, page: 1, total_count: listing.length } : {}));
  });
  await new Promise<void>((r) => server.listen(0, r));
  const client = new GiteaClient(`http://127.0.0.1:${(server.address() as any).port}`, "t");
  try {
    const got = await client.commitTrees("novox", "mesh-delivery", commit);
    assert.equal(got.root, "659bcaaac6c16972ec380267a4eba69d15558c26");
    assert.deepEqual(got.trees, { "modules/x": h("d") });
  } finally {
    server.close();
  }
});