import { mkdtempSync, rmSync } from "node:fs";
import os from "node:os";
import path from "node:path";
import { afterEach, beforeEach, describe, expect, it } from "vitest";
import type { PresetPackage } from "../src/types/preset.js";
import { checkAuthoringPreset } from "../src/preset/authoring-check.js";
import {
  checkoutVersion,
  commitVersion,
  loadVersionTree,
  versionLineage,
} from "../src/preset/versions.js";

function preset(id: string, content = "正文"): PresetPackage {
  return {
    id,
    name: id,
    source: "native",
    prompts: [
      { id: "sys", name: "规则", enabled: true, role: "system", content, marker: false, sourceIdentifier: "sys" },
      { id: "chatHistory", name: "对话历史", enabled: true, role: "system", content: "", marker: true, sourceIdentifier: "chatHistory" },
    ],
    promptOrder: [
      { promptId: "sys", enabled: true, orderIndex: 0 },
      { promptId: "chatHistory", enabled: true, orderIndex: 1 },
    ],
    generation: {},
    unsupported: [],
    importedAt: new Date().toISOString(),
  };
}

let dir = "";
beforeEach(() => {
  dir = mkdtempSync(path.join(os.tmpdir(), "preset-versions-"));
  process.env.WRITING_AGENT_DATA_DIR = dir;
});
afterEach(() => {
  delete process.env.WRITING_AGENT_DATA_DIR;
  rmSync(dir, { recursive: true, force: true });
});

describe("版本树", () => {
  it("线性保存并可追溯", () => {
    commitVersion({ presetId: "p1", preset: preset("p1", "v1") });
    const tree = commitVersion({ presetId: "p1", preset: preset("p1", "v2") });
    const lineage = versionLineage(tree, tree.currentId!);
    expect(lineage.map((n) => n.preset.prompts[0]!.content)).toEqual(["v1", "v2"]);
  });

  it("从历史节点分叉，原分支保持不变", () => {
    const first = commitVersion({ presetId: "p2", preset: preset("p2", "a") });
    const rootId = first.currentId!;
    commitVersion({ presetId: "p2", preset: preset("p2", "b") });
    const forked = commitVersion({ presetId: "p2", preset: preset("p2", "c"), parentId: rootId });
    expect(forked.nodes).toHaveLength(3);
    const branch = forked.nodes.filter((n) => n.parentId === rootId);
    expect(branch).toHaveLength(2);
    expect(versionLineage(forked, forked.currentId!)[0]!.id).toBe(rootId);
  });

  it("不允许再建第二个根，也不允许挂到不存在的父节点", () => {
    commitVersion({ presetId: "p3", preset: preset("p3") });
    expect(() => commitVersion({ presetId: "p3", preset: preset("p3"), parentId: null })).toThrow();
    expect(() => commitVersion({ presetId: "p3", preset: preset("p3"), parentId: "missing" })).toThrow();
  });

  it("checkout 只移动当前位置，不新增节点", () => {
    const tree = commitVersion({ presetId: "p4", preset: preset("p4") });
    const rootId = tree.currentId!;
    commitVersion({ presetId: "p4", preset: preset("p4", "x") });
    const moved = checkoutVersion("p4", rootId);
    expect(moved.currentId).toBe(rootId);
    expect(loadVersionTree("p4").nodes).toHaveLength(2);
  });

  it("拒绝非法预设 id（防路径穿越）", () => {
    expect(() => loadVersionTree("../evil")).toThrow();
  });
});

describe("结构检查", () => {
  it("正常预设没有 error", () => {
    const issues = checkAuthoringPreset(preset("ok"));
    expect(issues.filter((i) => i.level === "error")).toHaveLength(0);
  });

  it("全角 ｛｛ 给 warn 而不是 error", () => {
    const issues = checkAuthoringPreset(preset("fw", "你好 ｛｛user｛｛"));
    expect(issues.some((i) => i.level === "warn" && i.message.includes("全角"))).toBe(true);
    expect(issues.some((i) => i.level === "error")).toBe(false);
  });

  it("未闭合的 {{ 为 error", () => {
    const issues = checkAuthoringPreset(preset("open", "{{setvar::a::1"));
    expect(issues.some((i) => i.level === "error" && i.message.includes("未闭合"))).toBe(true);
  });

  it("未启用对话历史位置给 warn", () => {
    const p = preset("nohist");
    p.promptOrder = p.promptOrder.filter((o) => o.promptId !== "chatHistory");
    const issues = checkAuthoringPreset(p);
    expect(issues.some((i) => i.message.includes("对话历史"))).toBe(true);
  });
});