import { beforeEach, describe, expect, it } from "vitest";
import { db } from "@/db";
import { navItems, posts, tags } from "@/db/schema";
import {
  createComment,
  listApprovedComments,
  setCommentStatus,
} from "@/lib/services/comments";
import {
  buildSiteExport,
  importSiteExport,
  parseSiteExportJson,
} from "@/lib/services/import-export";
import { createPage } from "@/lib/services/pages";
import { createPost, getPublishedPostBySlug, type PostInput } from "@/lib/services/posts";
import { getSettings, listNavItems, saveSettings } from "@/lib/services/settings";
import { resetDb } from "../helpers/db";

const input = (overrides: Partial<PostInput> = {}): PostInput => ({
  title: "A post",
  slug: "",
  body: "<p>body</p>",
  authorName: "Tester",
  featuredImageUrl: null,
  featuredImageAlt: null,
  status: "published",
  tagIds: [],
  newTagNames: [],
  ...overrides,
});

beforeEach(resetDb);

/** Simulates writing the export to disk and reading it back. */
async function exportViaJson() {
  const parsed = parseSiteExportJson(JSON.stringify(await buildSiteExport()));
  if ("error" in parsed) throw new Error(parsed.error);
  return parsed.data;
}

describe("export/import round trip", () => {
  it("restores posts, tags, pages, nav, and settings from a JSON export", async () => {
    const published = await createPost(
      input({ title: "Keep me", newTagNames: ["Alpha", "Beta"] }),
    );
    await createPost(input({ title: "Draft one", status: "draft" }));
    const about = await createPage({
      title: "About",
      slug: "",
      body: "<p>hi</p>",
      status: "published",
    });
    await saveSettings(
      {
        siteTitle: "Round Trip",
        headerText: "hdr",
        footerText: "ftr",
        postsPerPage: 7,
        excerptWords: 25,
        homeMode: "page",
        homeTagId: null,
        homePageId: about.id,
        theme: "nord",
        font: "lora",
      },
      [
        { label: "About", url: null, pageId: about.id },
        { label: "Search", url: "https://example.com", pageId: null },
      ],
    );

    const snapshot = await exportViaJson();

    // Mutate everything, then restore.
    await db.delete(navItems);
    await db.delete(posts);
    await db.delete(tags);
    await createPost(input({ title: "Impostor" }));
    await importSiteExport(snapshot);

    const restored = await getPublishedPostBySlug(published.slug);
    expect(restored).not.toBeNull();
    expect(restored?.title).toBe("Keep me");
    expect(restored?.tags.map((t) => t.name).sort()).toEqual(["Alpha", "Beta"]);
    // Timestamps survive (public ordering depends on publishedAt).
    expect(restored?.publishedAt?.getTime()).toBe(published.publishedAt?.getTime());
    expect(await getPublishedPostBySlug("impostor")).toBeNull();

    const settings = await getSettings();
    expect(settings.siteTitle).toBe("Round Trip");
    expect(settings.postsPerPage).toBe(7);
    expect(settings.homeMode).toBe("page");
    expect(settings.theme).toBe("nord");
    expect(settings.font).toBe("lora");

    // home page and nav point at the re-created page row, not the old id.
    const nav = await listNavItems();
    expect(nav).toHaveLength(2);
    expect(nav[0].label).toBe("About");
    expect(nav[0].pageId).toBe(settings.homePageId);
    expect(nav[1].url).toBe("https://example.com");
  });

  it("round-trips threaded comments with remapped ids and statuses", async () => {
    const post = await createPost(input({ title: "Discussed" }));
    const parent = await createComment({
      postId: post.id,
      parentId: null,
      authorName: "Alice",
      authorEmail: "alice@example.com",
      emailPublic: true,
      body: "First!",
    });
    if (!parent.ok) throw new Error();
    await setCommentStatus(parent.comment.id, "approved");
    const reply = await createComment({
      postId: post.id,
      parentId: parent.comment.id,
      authorName: "Bob",
      authorEmail: "bob@example.com",
      emailPublic: false,
      body: "Replying to Alice",
    });
    if (!reply.ok) throw new Error();
    await setCommentStatus(reply.comment.id, "approved");
    await createComment({
      postId: post.id,
      parentId: parent.comment.id,
      authorName: "Spammer",
      authorEmail: "spam@example.com",
      emailPublic: false,
      body: "pending reply",
    });

    const snapshot = await exportViaJson();
    expect(snapshot.comments).toHaveLength(3);
    await importSiteExport(snapshot);

    const restored = await getPublishedPostBySlug(post.slug);
    const tree = await listApprovedComments(restored!.id);
    expect(tree).toHaveLength(1);
    expect(tree[0].authorEmail).toBe("alice@example.com"); // opted-in email survives
    expect(tree[0].replies).toHaveLength(1); // pending reply stays hidden
    expect(tree[0].replies[0].body).toBe("Replying to Alice");
    expect(tree[0].replies[0].authorEmail).toBeNull(); // private stays private
  });

  it("accepts version-1 exports (no comments field)", async () => {
    const snapshot = await exportViaJson();
    const v1 = { ...JSON.parse(JSON.stringify(snapshot)), version: 1 };
    delete v1.comments;
    const parsed = parseSiteExportJson(JSON.stringify(v1));
    expect(parsed).not.toHaveProperty("error");
    if ("data" in parsed) expect(parsed.data.comments).toEqual([]);
  });

  it("keeps draft posts and unpublished state intact", async () => {
    await createPost(input({ title: "Draft", status: "draft" }));
    const snapshot = await exportViaJson();
    await importSiteExport(snapshot);
    const [row] = await db.select().from(posts);
    expect(row.status).toBe("draft");
    expect(row.publishedAt).toBeNull();
  });

  it("sanitizes imported bodies", async () => {
    const snapshot = await exportViaJson();
    snapshot.posts.push({
      title: "Sneaky",
      slug: "sneaky",
      body: '<p>ok</p><script>alert("x")</script>',
      authorName: "Mallory",
      authorUsername: null,
      featuredImageUrl: null,
      featuredImageAlt: null,
      status: "published",
      createdAt: new Date(),
      updatedAt: new Date(),
      publishedAt: new Date(),
      tagSlugs: [],
    });
    await importSiteExport(snapshot);
    const post = await getPublishedPostBySlug("sneaky");
    expect(post?.body).toContain("<p>ok</p>");
    expect(post?.body).not.toContain("<script>");
  });
});

describe("parseSiteExportJson", () => {
  it("rejects non-JSON and foreign JSON", () => {
    expect(parseSiteExportJson("not json {")).toHaveProperty("error");
    expect(parseSiteExportJson('{"hello":"world"}')).toHaveProperty("error");
  });

  it("rejects posts referencing tags missing from the file", async () => {
    const snapshot = await exportViaJson();
    snapshot.posts.push({
      title: "Orphan",
      slug: "orphan",
      body: "",
      authorName: "A",
      authorUsername: null,
      featuredImageUrl: null,
      featuredImageAlt: null,
      status: "draft",
      createdAt: new Date(),
      updatedAt: new Date(),
      publishedAt: null,
      tagSlugs: ["missing-tag"],
    });
    const result = parseSiteExportJson(JSON.stringify(snapshot));
    expect(result).toHaveProperty("error");
    if ("error" in result) expect(result.error).toContain("missing-tag");
  });

  it("rejects duplicate slugs", async () => {
    const snapshot = await exportViaJson();
    snapshot.pages.push(
      { title: "P", slug: "same", body: "", status: "draft", createdAt: new Date(), updatedAt: new Date() },
      { title: "Q", slug: "same", body: "", status: "draft", createdAt: new Date(), updatedAt: new Date() },
    );
    const result = parseSiteExportJson(JSON.stringify(snapshot));
    expect(result).toHaveProperty("error");
  });

  it("rejects reply cycles in a crafted file", async () => {
    const snapshot = await exportViaJson();
    snapshot.posts.push({
      title: "P",
      slug: "p",
      body: "",
      authorName: "A",
      authorUsername: null,
      featuredImageUrl: null,
      featuredImageAlt: null,
      status: "published",
      createdAt: new Date(),
      updatedAt: new Date(),
      publishedAt: new Date(),
      tagSlugs: [],
    });
    const commentBase = {
      postSlug: "p",
      authorName: "X",
      authorEmail: "x@example.com",
      emailPublic: false,
      body: "hi",
      status: "approved" as const,
      createdAt: new Date(),
    };
    snapshot.comments = [
      { id: 1, parentId: 2, ...commentBase },
      { id: 2, parentId: 1, ...commentBase },
    ];
    const result = parseSiteExportJson(JSON.stringify(snapshot));
    expect(result).toHaveProperty("error");
    if ("error" in result) expect(result.error).toContain("cycle");
  });

  it("rejects a home tag that is not part of the export", async () => {
    const snapshot = await exportViaJson();
    snapshot.settings.homeMode = "tag";
    snapshot.settings.homeTagSlug = "ghost";
    const result = parseSiteExportJson(JSON.stringify(snapshot));
    expect(result).toHaveProperty("error");
  });
});