import fs from "fs";
import os from "os";
import path from "path";
import YAML from "js-yaml";
import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
import { deepMerge } from "../lib/memory/config-loader.js";

// ── Mocks ──────────────────────────────────────────────────────
//
// We mock Agent entirely. Real Agent.init() exercises memory/session/desk/bridge
// init which we don't care about here. The mock only implements the minimum
// for createAgent's flow: init (read config.yaml), updateConfig (merge + write),
// and no-op setters.
vi.mock("../core/agent.js", () => ({
  Agent: vi.fn().mockImplementation(function (opts) {
    // 对齐真实 Agent 构造：id 是唯一信源，agentDir 从 agentsDir + id 派生
    this.id = opts.id;
    this.agentsDir = opts.agentsDir;
    this.agentDir = path.join(opts.agentsDir, opts.id);
    this.config = {};
    this.init = async () => {
      const cfgPath = path.join(this.agentDir, "config.yaml");
      if (fs.existsSync(cfgPath)) {
        this.config = YAML.load(fs.readFileSync(cfgPath, "utf-8")) || {};
      }
    };
    this.updateConfig = (partial) => {
      const cfgPath = path.join(this.agentDir, "config.yaml");
      const existing = fs.existsSync(cfgPath)
        ? YAML.load(fs.readFileSync(cfgPath, "utf-8")) || {}
        : {};
      const merged = deepMerge(existing, partial);
      fs.writeFileSync(cfgPath, YAML.dump(merged));
      this.config = merged;
    };
    this.setGetOwnerIds = vi.fn();
    this.setCallbacks = vi.fn();
    this.setOnInstallCallback = vi.fn();
    this.setNotifyHandler = vi.fn();
    this.setDescriptionRefreshHandler = vi.fn();
    this.dispose = vi.fn();
  }),
}));

vi.mock("../lib/debug-log.js", () => ({
  createModuleLogger: () => ({ log: vi.fn(), warn: vi.fn(), error: vi.fn() }),
}));

vi.mock("../lib/desk/activity-store.js", () => ({
  ActivityStore: vi.fn(),
}));

vi.mock("../lib/memory/config-loader.js", async (importOriginal) => {
  const actual = await importOriginal();
  return { ...actual, clearConfigCache: vi.fn() };
});

vi.mock("../core/llm-utils.js", () => ({
  generateAgentId: vi.fn().mockImplementation(async (_u, name) => `agent-${name.toLowerCase()}`),
  generateDescription: vi.fn(),
}));

// Import AFTER vi.mock calls so the mocks take effect.
import { AgentManager } from "../core/agent-manager.js";

// ── Test suite ─────────────────────────────────────────────────
describe("AgentManager.createAgent default skills.enabled", () => {
  let tempDir;
  let agentsDir;
  let productDir;
  let mgr;
  let skillsMock;

  function seedTemplate(enabledLiteral = '["skill-creator"]') {
    fs.writeFileSync(
      path.join(productDir, "config.example.yaml"),
      [
        "agent:",
        "  name: Hanako",
        "  yuan: hanako",
        "user:",
        '  name: ""',
        "api:",
        '  provider: ""',
        "models:",
        '  chat: ""',
        "skills:",
        `  enabled: ${enabledLiteral}`,
      ].join("\n"),
    );
  }

  function makeMgr() {
    return new AgentManager({
      agentsDir,
      productDir,
      userDir: tempDir,
      channelsDir: tempDir,
      getPrefs: () => ({
        getPrimaryAgent: () => null,
        getPreferences: () => ({}),
        savePrimaryAgent: vi.fn(),
      }),
      getModels: () => ({
        resolveModelWithCredentials: vi.fn(),
        defaultModel: { id: "test-model", provider: "test-provider" },
        availableModels: [],
      }),
      getHub: () => ({
        scheduler: {
          startAgentCron: vi.fn(),
          startAgentHeartbeat: vi.fn(),
        },
        dmRouter: null,
      }),
      getSkills: () => skillsMock,
      getSearchConfig: () => ({}),
      resolveUtilityConfig: () => ({}),
      getSharedModels: () => ({}),
      getChannelManager: () => ({
        setupChannelsForNewAgent: vi.fn(),
        cleanupAgentFromChannels: vi.fn(),
      }),
      getSessionCoordinator: () => ({}),
    });
  }

  beforeEach(() => {
    tempDir = fs.mkdtempSync(path.join(os.tmpdir(), "hana-create-defaults-"));
    agentsDir = path.join(tempDir, "agents");
    productDir = tempDir;
    fs.mkdirSync(agentsDir);
    seedTemplate();

    skillsMock = {
      _allSkills: [],
      computeDefaultEnabledForNewAgent() {
        return this._allSkills
          .filter((s) => s.source !== "learned" && s.source !== "external")
          .map((s) => s.name);
      },
      syncAgentSkills: vi.fn(),
    };

    mgr = makeMgr();
  });

  afterEach(() => {
    try { fs.rmSync(tempDir, { recursive: true, force: true }); } catch {}
  });

  it("writes snapshot of installed user skills to new agent config.yaml", async () => {
    skillsMock._allSkills = [
      { name: "pdf", source: "user" },
      { name: "docx", source: "user" },
      { name: "learned-one", source: "learned", _agentId: "someone-else" },
      { name: "ext-one", source: "external" },
    ];

    const { id: newId } = await mgr.createAgent({ name: "TestAgent", yuan: "hanako" });

    const cfgPath = path.join(agentsDir, newId, "config.yaml");
    const cfg = YAML.load(fs.readFileSync(cfgPath, "utf-8"));
    expect(cfg.skills.enabled).toEqual(["pdf", "docx"]);
  });

  it("falls back to seeded template default when snapshot is empty", async () => {
    skillsMock._allSkills = [];

    const { id: newId } = await mgr.createAgent({ name: "EmptyAgent", yuan: "hanako" });

    const cfgPath = path.join(agentsDir, newId, "config.yaml");
    const cfg = YAML.load(fs.readFileSync(cfgPath, "utf-8"));
    // The test seeds the template literally with ["skill-creator"], so that's
    // what should remain when our new fill code doesn't execute.
    expect(cfg.skills.enabled).toEqual(["skill-creator"]);
  });

  it("does not touch existing agents' config.yaml (regression for #419)", async () => {
    skillsMock._allSkills = [{ name: "pdf", source: "user" }];

    const { id: firstId } = await mgr.createAgent({ name: "First", yuan: "hanako" });
    const firstCfgPath = path.join(agentsDir, firstId, "config.yaml");
    const mtimeBefore = fs.statSync(firstCfgPath).mtimeMs;

    // Wait 20ms so filesystem mtime resolution can distinguish any write
    await new Promise((r) => setTimeout(r, 20));

    await mgr.createAgent({ name: "Second", yuan: "hanako" });

    const mtimeAfter = fs.statSync(firstCfgPath).mtimeMs;
    expect(mtimeAfter).toBe(mtimeBefore);
  });

  it("persists models.chat as composite ref for newly created agents", async () => {
    skillsMock._allSkills = [];

    const { id: newId } = await mgr.createAgent({ name: "CompositeAgent", yuan: "hanako" });

    const cfgPath = path.join(agentsDir, newId, "config.yaml");
    const cfg = YAML.load(fs.readFileSync(cfgPath, "utf-8"));
    expect(cfg.models.chat).toEqual({ id: "test-model", provider: "test-provider" });
  });
});
