// Root Unit Tests — pickServer(), findRoot(), pathToUri(), uriToPath().
import { describe, it } from "node:test";
import * as assert from "node:assert/strict";
import * as path from "node:path";
import { fileURLToPath } from "node:url";
import { pickServer, findRoot, pathToUri, uriToPath } from "../../src/root.ts";
import { UnsupportedExtensionError } from "../../src/types.ts";

const __dirname = path.dirname(fileURLToPath(import.meta.url));
const projectRoot = path.resolve(__dirname, "..", "..");

describe("pathToUri / uriToPath", () => {
  it("converts a relative path to a file URI", () => {
    const uri = pathToUri("cli.ts");
    assert.ok(uri.startsWith("file://"));
    assert.ok(uri.endsWith("cli.ts"));
  });

  it("converts an absolute path to a file URI", () => {
    const absPath = path.resolve(projectRoot, "cli.ts");
    const uri = pathToUri(absPath);
    assert.strictEqual(uri, `file://${absPath}`);
  });

  it("round-trips path -> uri -> path", () => {
    const absPath = path.resolve(projectRoot, "src", "client.ts");
    const uri = pathToUri(absPath);
    const back = uriToPath(uri);
    assert.strictEqual(back, absPath);
  });
});

describe("pickServer", () => {
  it("picks gopls for .go files", () => {
    const server = pickServer("/some/path/file.go");
    assert.strictEqual(server.id, "gopls");
  });

  it("picks typescript-language-server for .ts files", () => {
    const server = pickServer("/some/path/file.ts");
    assert.strictEqual(server.id, "typescript-language-server");
  });

  it("picks typescript-language-server for .tsx files", () => {
    const server = pickServer("/some/path/file.tsx");
    assert.strictEqual(server.id, "typescript-language-server");
  });

  it("picks pyright for .py files", () => {
    const server = pickServer("/some/path/file.py");
    assert.strictEqual(server.id, "pyright");
  });

  it("throws UnsupportedExtensionError for unknown extensions", () => {
    assert.throws(
      () => pickServer("/some/path/file.xyz"),
      UnsupportedExtensionError,
    );
  });
});

describe("findRoot", () => {
  it("finds project root using go.mod marker", () => {
    // The project root has package.json but not go.mod, so use a file in the
    // project and look for tsconfig.json.
    const root = findRoot(
      path.join(projectRoot, "cli.ts"),
      ["tsconfig.json"],
    );
    assert.strictEqual(root, projectRoot);
  });

  it("finds nearest directory containing marker", () => {
    // The test/fixtures/ dir doesn't have tsconfig.json, but the project root does.
    const fixtureFile = path.join(projectRoot, "test", "fixtures", "sample.ts");
    const root = findRoot(fixtureFile, ["tsconfig.json"]);
    assert.strictEqual(root, projectRoot);
  });

  it("falls back to file's directory when no marker found", () => {
    const root = findRoot(
      path.join(projectRoot, "cli.ts"),
      ["nonexistent-marker-xyz"],
    );
    assert.strictEqual(root, projectRoot);
  });
});