import { afterEach, describe, expect, it, vi } from "vitest";
import { api, ApiFallbackError, getApiFallback } from "./client";

afterEach(() => {
  vi.unstubAllGlobals();
});

describe("api fallback helpers", () => {
  it("extracts typed fallback payloads", () => {
    expect(getApiFallback<string[]>(new ApiFallbackError("offline", ["demo"]))).toEqual(["demo"]);
  });

  it("ignores non fallback errors", () => {
    expect(getApiFallback<string[]>(new Error("boom"))).toBeUndefined();
  });

  it("does not send JSON content-type for bodyless delete requests", async () => {
    const fetchMock = vi.fn().mockResolvedValue(
      new Response(JSON.stringify({ ok: true }), {
        status: 200,
        headers: { "Content-Type": "application/json" }
      })
    );
    vi.stubGlobal("fetch", fetchMock);

    await api.deleteLibrary(42);

    const init = fetchMock.mock.calls[0][1] as RequestInit;
    const headers = new Headers(init.headers);
    expect(init.method).toBe("DELETE");
    expect(headers.has("Content-Type")).toBe(false);
  });

  it("surfaces create library API errors without fallback", async () => {
    const fetchMock = vi.fn().mockResolvedValue(
      new Response(JSON.stringify({ message: "Library path does not exist" }), {
        status: 400,
        statusText: "Bad Request",
        headers: { "Content-Type": "application/json" }
      })
    );
    vi.stubGlobal("fetch", fetchMock);

    await expect(api.createLibrary({ name: "Books", path: "/missing", enabled: true })).rejects.toThrow("Library path does not exist");
  });

  it("does not fallback when scan enqueue fails", async () => {
    const fetchMock = vi.fn().mockRejectedValue(new Error("offline"));
    vi.stubGlobal("fetch", fetchMock);

    await expect(api.scanLibrary(42)).rejects.toThrow("offline");
  });

  it("keeps reader preferences locally when the backend contract is absent", async () => {
    const storage = new Map<string, string>();
    vi.stubGlobal("localStorage", {
      getItem: (key: string) => storage.get(key) ?? null,
      setItem: (key: string, value: string) => storage.set(key, value),
      removeItem: (key: string) => storage.delete(key),
      clear: () => storage.clear()
    });
    const fetchMock = vi.fn().mockResolvedValue(new Response("", { status: 404, statusText: "Not Found" }));
    vi.stubGlobal("fetch", fetchMock);

    await expect(api.readerPreferences(8)).resolves.toEqual({ mode: "horizontal", fit: "page" });
    await expect(api.saveReaderPreferences(8, { mode: "vertical", fit: "width" })).resolves.toEqual({ mode: "vertical", fit: "width" });
    expect(storage.get("readabook:reader-preferences:8")).toBe(JSON.stringify({ mode: "vertical", fit: "width" }));
  });

  it("sends metadata source updates to the admin endpoint", async () => {
    const fetchMock = vi.fn().mockResolvedValue(
      new Response(JSON.stringify({ isbnPriorityEnabled: false, sources: [] }), {
        status: 200,
        headers: { "Content-Type": "application/json" }
      })
    );
    vi.stubGlobal("fetch", fetchMock);

    await api.updateMetadataSources({
      isbnPriorityEnabled: false,
      sources: [{ provider: "openlibrary", enabled: true, priority: 1 }]
    });

    expect(fetchMock.mock.calls[0][0]).toBe("/admin/metadata-sources");
    const init = fetchMock.mock.calls[0][1] as RequestInit;
    expect(init.method).toBe("PUT");
    expect(JSON.parse(init.body as string)).toEqual({
      isbnPriorityEnabled: false,
      sources: [{ provider: "openlibrary", enabled: true, priority: 1 }]
    });
  });

  it("sends automation settings to the admin endpoint", async () => {
    const fetchMock = vi.fn().mockResolvedValue(
      new Response(
        JSON.stringify({
          watchLibraries: true,
          autoEnrichNewBooks: true,
          scanSchedule: { frequency: "daily", time: "03:00", dayOfWeek: 1 },
          enrichSchedule: { frequency: "disabled", time: "04:00", dayOfWeek: 1 }
        }),
        {
          status: 200,
          headers: { "Content-Type": "application/json" }
        }
      )
    );
    vi.stubGlobal("fetch", fetchMock);

    await api.updateAutomationSettings({
      watchLibraries: true,
      scanSchedule: { frequency: "daily", time: "03:00", dayOfWeek: 1 }
    });

    expect(fetchMock.mock.calls[0][0]).toBe("/admin/automation");
    const init = fetchMock.mock.calls[0][1] as RequestInit;
    expect(init.method).toBe("PUT");
    expect(JSON.parse(init.body as string)).toEqual({
      watchLibraries: true,
      scanSchedule: { frequency: "daily", time: "03:00", dayOfWeek: 1 }
    });
  });
});