import { describe, it, expect } from "vitest";
import { formatErrorForUser } from "../../src/error-formatter.js";

describe("formatErrorForUser", () => {
  it("includes the error name for standard Error instances", () => {
    const err = new TypeError("something went wrong");
    const result = formatErrorForUser(err);
    expect(result).toContain("TypeError");
    expect(result).toContain("something went wrong");
  });

  it("includes custom error names", () => {
    const err = new Error("bad auth");
    err.name = "AuthenticationError";
    const result = formatErrorForUser(err);
    expect(result).toContain("AuthenticationError");
    expect(result).toContain("bad auth");
  });

  it("excludes stack traces from error messages", () => {
    const err = new Error("fail\n  at Object.<anonymous> (/home/user/app.js:10:5)\n  at Module._compile (node:internal/modules/cjs/loader:1234:14)");
    const result = formatErrorForUser(err);
    expect(result).not.toMatch(/\bat\s+/);
    expect(result).not.toContain("app.js");
  });

  it("excludes API keys (sk-... pattern)", () => {
    const err = new Error("Auth failed with key sk-ant-api03-abcdefghijklmnop");
    const result = formatErrorForUser(err);
    expect(result).not.toContain("sk-ant-api03");
    expect(result).toContain("[REDACTED]");
  });

  it("excludes Unix file paths", () => {
    const err = new Error("File not found: /home/user/projects/app/config.ts");
    const result = formatErrorForUser(err);
    expect(result).not.toContain("/home/user");
    expect(result).toContain("[REDACTED_PATH]");
  });

  it("excludes Windows file paths", () => {
    const err = new Error("Cannot read C:\\Users\\admin\\secrets.txt");
    const result = formatErrorForUser(err);
    expect(result).not.toContain("C:\\Users");
    expect(result).toContain("[REDACTED_PATH]");
  });

  it("handles string errors", () => {
    const result = formatErrorForUser("something broke");
    expect(result).toBe("Error: something broke");
  });

  it("handles non-Error, non-string values", () => {
    expect(formatErrorForUser(42)).toBe("An unknown error occurred");
    expect(formatErrorForUser(null)).toBe("An unknown error occurred");
    expect(formatErrorForUser(undefined)).toBe("An unknown error occurred");
  });

  it("handles Error with empty message", () => {
    const err = new Error("");
    err.name = "RangeError";
    const result = formatErrorForUser(err);
    expect(result).toContain("RangeError");
  });
});