import { describe, expect, test } from "bun:test";
import { rm, writeFile } from "node:fs/promises";
import { tmpdir } from "node:os";
import { join } from "node:path";

import { loadServerConfig, parseRuntimeArgs } from "../../src/server/config";

describe("parseRuntimeArgs", () => {
  test("无参数返回空对象", () => {
    const result = parseRuntimeArgs([]);
    expect(result).toEqual({});
  });

  test("有参数返回 configPath", () => {
    const result = parseRuntimeArgs(["config.yaml"]);
    expect(result).toEqual({ configPath: "config.yaml" });
  });
});

describe("loadServerConfig", () => {
  test("无 configPath 使用默认值", async () => {
    const config = await loadServerConfig();
    expect(config.host).toBe("127.0.0.1");
    expect(config.port).toBe(3000);
  });

  test("环境变量 HOST 覆盖默认值", async () => {
    const prev = process.env["HOST"];
    process.env["HOST"] = "0.0.0.0";
    try {
      const config = await loadServerConfig();
      expect(config.host).toBe("0.0.0.0");
    } finally {
      if (prev === undefined) {
        delete process.env["HOST"];
      } else {
        process.env["HOST"] = prev;
      }
    }
  });

  test("环境变量 PORT 覆盖默认值", async () => {
    const prev = process.env["PORT"];
    process.env["PORT"] = "8080";
    try {
      const config = await loadServerConfig();
      expect(config.port).toBe(8080);
    } finally {
      if (prev === undefined) {
        delete process.env["PORT"];
      } else {
        process.env["PORT"] = prev;
      }
    }
  });

  test("YAML 配置文件不存在时报错", async () => {
    try {
      await loadServerConfig("/nonexistent/path/config.yaml");
      expect.unreachable();
    } catch (error) {
      expect((error as Error).message).toContain("配置文件不存在");
    }
  });

  test("YAML 配置文件加载 server 配置", async () => {
    const temp = tmpdir();
    const yamlPath = join(temp, "test-config.yaml");
    const yamlContent = 'server:\n  host: "0.0.0.0"\n  port: 9999\n';
    await writeFile(yamlPath, yamlContent);

    try {
      const config = await loadServerConfig(yamlPath);
      expect(config.host).toBe("0.0.0.0");
      expect(config.port).toBe(9999);
    } finally {
      await rm(yamlPath, { force: true });
    }
  });

  test("YAML 缺少 server 字段时使用默认值", async () => {
    const temp = tmpdir();
    const yamlPath = join(temp, "test-empty.yaml");
    const yamlContent = "runtime:\n  debug: true\n";
    await writeFile(yamlPath, yamlContent);

    try {
      const config = await loadServerConfig(yamlPath);
      expect(config.host).toBe("127.0.0.1");
      expect(config.port).toBe(3000);
    } finally {
      await rm(yamlPath, { force: true });
    }
  });
});