import { describe, it, expect, beforeEach, afterEach } from "vitest";
import { mkdtempSync, writeFileSync, rmSync, mkdirSync } from "node:fs";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { resolveIdentity } from "../src/identity.js";

let dir: string;
beforeEach(() => {
  dir = mkdtempSync(join(tmpdir(), "watcher-id-"));
});
afterEach(() => {
  rmSync(dir, { recursive: true, force: true });
});

describe("resolveIdentity", () => {
  it("uses PING_AGENT_IDENTITY env var first", () => {
    writeFileSync(join(dir, ".ping-agent"), "default-agent\n");
    const r = resolveIdentity({
      HOME: dir,
      PING_AGENT_IDENTITY: "envname",
    });
    expect(r.agent).toBe("envname");
    expect(r.source).toMatch(/env/i);
  });

  it("uses $CLAUDE_HOME/ping-agent next", () => {
    writeFileSync(join(dir, ".ping-agent"), "default-agent\n");
    const claudeHome = join(dir, "claude-sandbox");
    mkdirSync(claudeHome);
    writeFileSync(join(claudeHome, "ping-agent"), "sandbox\n");
    const r = resolveIdentity({
      HOME: dir,
      CLAUDE_HOME: claudeHome,
      PING_AGENT_IDENTITY: "",
    });
    expect(r.agent).toBe("sandbox");
    expect(r.source).toContain(claudeHome);
  });

  it("falls through to ~/.ping-agent", () => {
    writeFileSync(join(dir, ".ping-agent"), "bob\n");
    const r = resolveIdentity({ HOME: dir });
    expect(r.agent).toBe("bob");
    expect(r.source).toContain(".ping-agent");
  });

  it("throws when nothing resolves", () => {
    expect(() => resolveIdentity({ HOME: dir })).toThrow(/no identity/);
  });

  it("ignores empty CLAUDE_HOME/ping-agent and falls through", () => {
    writeFileSync(join(dir, ".ping-agent"), "bob\n");
    const claudeHome = join(dir, "claude-sandbox");
    mkdirSync(claudeHome);
    writeFileSync(join(claudeHome, "ping-agent"), "");
    const r = resolveIdentity({ HOME: dir, CLAUDE_HOME: claudeHome });
    expect(r.agent).toBe("bob");
  });

  it("trims whitespace from identity files", () => {
    writeFileSync(join(dir, ".ping-agent"), "  bob  \n\n");
    const r = resolveIdentity({ HOME: dir });
    expect(r.agent).toBe("bob");
  });
});