import { screen } from "@testing-library/react";
import { describe, expect, it } from "vitest";
import { dune, renderApp, signedIn } from "../test/helpers";

const fresh = { ...dune, current_page: 0, status: "not_started" as const };

describe("BookForm", () => {
  it("adds a book and opens it", async () => {
    const calls = signedIn({
      "POST /api/books": () => [201, fresh],
      "GET /api/books/7": () => [200, fresh],
    });
    const user = renderApp("/books/new");
    await screen.findByRole("option", { name: "Science Fiction" });
    await user.type(screen.getByLabelText("Title"), "Dune");
    await user.type(screen.getByLabelText("Author"), "Frank Herbert");
    await user.selectOptions(screen.getByLabelText("Genre"), "Science Fiction");
    await user.type(screen.getByLabelText("Total pages"), "380");
    await user.click(screen.getByRole("button", { name: "Add book" }));

    expect(
      await screen.findByRole("heading", { name: "Dune", level: 1 }),
    ).toBeInTheDocument();
    expect(calls).toContainEqual({
      method: "POST",
      path: "/api/books",
      body: {
        title: "Dune",
        author: "Frank Herbert",
        genre_id: 5,
        total_pages: 380,
        current_page: 0,
      },
    });
  });

  it("shows a server validation error against the field", async () => {
    signedIn({
      "POST /api/books": () => [
        400,
        { error: "Unknown genre_id; see GET /api/genres", field: "genre_id" },
      ],
    });
    const user = renderApp("/books/new");
    await screen.findByRole("option", { name: "Science Fiction" });
    await user.type(screen.getByLabelText("Title"), "Dune");
    await user.type(screen.getByLabelText("Author"), "Frank Herbert");
    await user.selectOptions(screen.getByLabelText("Genre"), "Science Fiction");
    await user.type(screen.getByLabelText("Total pages"), "380");
    await user.click(screen.getByRole("button", { name: "Add book" }));

    expect(await screen.findByRole("alert")).toHaveTextContent(
      "Unknown genre_id",
    );
    expect(screen.getByLabelText("Genre")).toHaveAttribute(
      "aria-invalid",
      "true",
    );
  });

  it("edits an existing book", async () => {
    let saved = dune;
    const calls = signedIn({
      "GET /api/books/7": () => [200, saved],
      "PATCH /api/books/7": ({ body }) => {
        saved = { ...saved, ...(body as object) };
        return [200, saved];
      },
    });
    const user = renderApp("/books/7/edit");
    const title = await screen.findByDisplayValue("Dune");
    await user.clear(title);
    await user.type(title, "Dune Messiah");
    await user.click(screen.getByRole("button", { name: "Save changes" }));

    expect(
      await screen.findByRole("heading", { name: "Dune Messiah", level: 1 }),
    ).toBeInTheDocument();
    expect(calls).toContainEqual({
      method: "PATCH",
      path: "/api/books/7",
      body: { title: "Dune Messiah" },
    });
  });

  it("retries a failed load and shows the prefilled form", async () => {
    let attempts = 0;
    signedIn({
      "GET /api/books/7": () =>
        ++attempts === 1
          ? [500, { error: "Database unavailable" }]
          : [200, dune],
    });
    const user = renderApp("/books/7/edit");
    expect(await screen.findByRole("alert")).toHaveTextContent(
      "Database unavailable",
    );
    await user.click(screen.getByRole("button", { name: "Retry" }));
    expect(await screen.findByLabelText("Title")).toHaveValue("Dune");
  });

  it("saving without changes returns to the book without a request", async () => {
    const calls = signedIn({
      "GET /api/books/7": () => [200, dune],
      "GET /api/books/7/notes": () => [200, []],
    });
    const user = renderApp("/books/7/edit");
    await screen.findByDisplayValue("Dune");
    await user.click(screen.getByRole("button", { name: "Save changes" }));

    await screen.findByRole("heading", { name: "Dune", level: 1 });
    expect(calls.some((call) => call.method === "PATCH")).toBe(false);
  });

  it("preserves progress saved in another session when only the title changes", async () => {
    let saved = { ...dune };
    signedIn({
      "GET /api/books/7": () => [200, { ...saved }],
      "GET /api/books/7/notes": () => [200, []],
      "PATCH /api/books/7": ({ body }) => {
        saved = { ...saved, ...(body as object) };
        return [200, saved];
      },
    });
    const user = renderApp("/books/7/edit");
    const title = await screen.findByDisplayValue("Dune");
    await screen.findByRole("option", { name: "Science Fiction" });

    // Another session saves progress after this form loads its snapshot.
    saved = { ...saved, current_page: 300 };
    await user.clear(title);
    await user.type(title, "Dune Messiah");
    await user.click(screen.getByRole("button", { name: "Save changes" }));

    await screen.findByRole("heading", { name: "Dune Messiah", level: 1 });
    expect(screen.getByRole("progressbar")).toHaveAttribute("value", "300");
  });
});