import { createHash } from "node:crypto";
import { readFileSync } from "node:fs";
import { createRequire } from "node:module";
import path from "node:path";
import { describe, expect, it } from "vitest";

type OfflineFallback = { kind: "redirect"; to: string } | { kind: "cached-path"; path: string };
type NavigationPlan =
  | { kind: "browser" }
  | { kind: "cache-first" }
  | { kind: "network-first"; timeoutMs: number; redirectOnTimeout: boolean };

interface SwRoutes {
  SHELL_ROUTES: readonly string[];
  offlineFallbackFor: (url: URL) => OfflineFallback;
  offlineHomeFor: (url: URL) => string;
  navigationPlanFor: (url: URL) => NavigationPlan;
  isShellRoute: (pathname: string) => boolean;
  extractAssetUrls: (html: string) => string[];
  isCacheableApiPath: (pathname: string) => boolean;
  shouldCacheApi: (url: URL, apiOrigin: string | null) => boolean;
  apiOriginFrom: (config: unknown) => string | null;
  isRoutePayload: (url: URL) => boolean;
  buildAssetsToPrune: (
    cached: { url: string; date: number | null }[],
    current: readonly string[],
    now: number,
  ) => string[];
}

// The service worker's routing rules are a plain script (public/), loaded by
// the worker with importScripts - here as CommonJS.
const require = createRequire(import.meta.url);
// Vitest runs from the frontend root.
const PUBLIC_DIR = path.resolve(process.cwd(), "public");
const routes = require(path.join(PUBLIC_DIR, "sw-routes.js")) as SwRoutes;

const APP = "https://apicore.example";
const API = "https://apicorebackend.example";
const DAY_MS = 24 * 60 * 60 * 1000;

function fallbackFor(path: string): OfflineFallback {
  return routes.offlineFallbackFor(new URL(path, APP));
}

function planFor(path: string): NavigationPlan {
  return routes.navigationPlanFor(new URL(path, APP));
}

function cachesApi(path: string, origin = API): boolean {
  return routes.shouldCacheApi(new URL(path, origin), API);
}

describe("service worker routes", () => {
  it("maps /colonies/abc to /offline/colony?id=abc and encodes ids", () => {
    expect(fallbackFor("/colonies/abc")).toEqual({
      kind: "redirect",
      to: "/offline/colony?id=abc&from=%2Fcolonies%2Fabc",
    });
    expect(fallbackFor("/colonies/abc/")).toEqual({
      kind: "redirect",
      to: "/offline/colony?id=abc&from=%2Fcolonies%2Fabc%2F",
    });
    expect(fallbackFor("/apiaries/xyz")).toEqual({
      kind: "redirect",
      to: "/offline/apiary?id=xyz&from=%2Fapiaries%2Fxyz",
    });
    expect(fallbackFor("/colonies/a%20b%26c%3Dd")).toEqual({
      kind: "redirect",
      to: "/offline/colony?id=a%20b%26c%3Dd&from=%2Fcolonies%2Fa%2520b%2526c%253Dd",
    });
    expect(fallbackFor("/colonies/a&b=c#x")).toEqual({
      kind: "redirect",
      to: "/offline/colony?id=a%26b%3Dc&from=%2Fcolonies%2Fa%26b%3Dc",
    });
  });

  it("serves /inspections/new?colonyId=x from the cached shell path", () => {
    expect(fallbackFor("/inspections/new?colonyId=x&round=apiary-1")).toEqual({
      kind: "cached-path",
      path: "/inspections/new",
    });
    expect(fallbackFor("/offline/colony?id=abc")).toEqual({
      kind: "cached-path",
      path: "/offline/colony",
    });
    expect(fallbackFor("/dashboard/")).toEqual({ kind: "cached-path", path: "/dashboard" });
    for (const route of [
      "/",
      "/login",
      "/dashboard",
      "/offline",
      "/offline/apiary",
      "/offline/colony",
      "/inspections/new",
      "/varroa/new",
      "/treatments/new",
      "/feedings/new",
      "/swarm-control/new",
    ]) {
      expect(routes.isShellRoute(route)).toBe(true);
    }
    expect(routes.SHELL_ROUTES).toHaveLength(11);
  });

  it("unknown routes go to /offline and remember where the user wanted to go", () => {
    expect(fallbackFor("/statistics?year=2026")).toEqual({
      kind: "redirect",
      to: "/offline?from=%2Fstatistics%3Fyear%3D2026",
    });
    for (const path of [
      "/colonies",
      "/colonies/new",
      "/apiaries/new",
      "/apiaries/map",
      "/colonies/abc/edit",
      "/colonies/%E0%A4%A",
      "/harvests/new",
    ]) {
      const fallback = fallbackFor(path);
      expect(fallback.kind).toBe("redirect");
      expect(fallback.kind === "redirect" && fallback.to.startsWith("/offline?from=")).toBe(true);
    }
    expect(routes.isShellRoute("/statistics")).toBe(false);
    expect(routes.offlineHomeFor(new URL("/queens/q-1", APP))).toBe("/offline?from=%2Fqueens%2Fq-1");
  });

  it("plans each navigation by its route", () => {
    expect(planFor("/offline")).toEqual({ kind: "cache-first" });
    expect(planFor("/offline/apiary?id=a-1")).toEqual({ kind: "cache-first" });
    expect(planFor("/offline/colony?id=c-1")).toEqual({ kind: "cache-first" });
    // Shell pages answer from the cache after 4 s - without one, the network
    // keeps its chance (no dead end on a slow line).
    expect(planFor("/inspections/new?colonyId=c-1")).toEqual({
      kind: "network-first",
      timeoutMs: 4000,
      redirectOnTimeout: false,
    });
    expect(planFor("/")).toEqual({ kind: "network-first", timeoutMs: 4000, redirectOnTimeout: false });
    // A scanned QR code at the apiary: the offline view after 10 s.
    expect(planFor("/colonies/c-1")).toEqual({
      kind: "network-first",
      timeoutMs: 10000,
      redirectOnTimeout: true,
    });
    expect(planFor("/apiaries/a-1")).toEqual({
      kind: "network-first",
      timeoutMs: 10000,
      redirectOnTimeout: true,
    });
    expect(planFor("/statistics")).toEqual({
      kind: "network-first",
      timeoutMs: 15000,
      redirectOnTimeout: true,
    });
  });

  it("leaves navigations to /api/ to the browser", () => {
    expect(planFor("/api/runtime-config")).toEqual({ kind: "browser" });
    expect(planFor("/api/v1/documents/d-1/download")).toEqual({ kind: "browser" });
  });

  it("never caches /api/v1/auth/*", () => {
    for (const path of [
      "/api/v1/auth/me",
      "/api/v1/auth/refresh",
      "/api/v1/auth/sso/status",
      "/api/v1/auth",
      "/api/v1/Auth/me",
    ]) {
      expect(cachesApi(path)).toBe(false);
    }
    expect(cachesApi("/api/v1/authors")).toBe(true);
  });

  it("never caches what the offline packs answer, so the pack answers offline", () => {
    for (const path of [
      "/api/v1/colonies",
      "/api/v1/colonies/",
      "/api/v1/colonies?status=ACTIVE",
      "/api/v1/colonies/c-1/inspections",
      "/api/v1/apiaries/a-1/colony-overview",
      "/api/v1/apiaries/a-1/offline-pack",
    ]) {
      expect(cachesApi(path)).toBe(false);
    }
    expect(cachesApi("/api/v1/colonies/c-1")).toBe(true);
    expect(cachesApi("/api/v1/tasks")).toBe(true);
  });

  it("never caches apiaries themselves - they carry coordinates and the address", () => {
    for (const path of ["/api/v1/apiaries", "/api/v1/apiaries/", "/api/v1/apiaries/a-1", "/api/v1/apiaries/a-1/"]) {
      expect(cachesApi(path)).toBe(false);
    }
    expect(cachesApi("/api/v1/apiaries/a-1/weather")).toBe(true);
  });

  it("never caches exports and backups - full records incl. coordinates, addresses, megabytes", () => {
    for (const path of [
      "/api/v1/export/apiaries.json",
      "/api/v1/export/treatment-log.pdf",
      "/api/v1/export/colonies.csv",
      "/api/v1/Export/apiaries.json",
      "/api/v1/backup/export",
      "/api/v1/backup",
    ]) {
      expect(cachesApi(path)).toBe(false);
    }
    expect(cachesApi("/api/v1/exporters")).toBe(true);
  });

  it("caches only answers of the configured backend", () => {
    expect(cachesApi("/api/v1/tasks", "https://elsewhere.example")).toBe(false);
    expect(routes.shouldCacheApi(new URL("/api/v1/tasks", API), null)).toBe(false);
    expect(routes.shouldCacheApi(new URL("/api/runtime-config", APP), APP)).toBe(false);
    expect(routes.shouldCacheApi(new URL("/_next/static/chunks/main.js", APP), APP)).toBe(false);
    expect(routes.apiOriginFrom({ apiUrl: `${API}/api/v1` })).toBe(API);
    expect(routes.apiOriginFrom({ apiUrl: "kein url" })).toBeNull();
    expect(routes.apiOriginFrom(null)).toBeNull();
    expect(routes.isCacheableApiPath("/api/v1/apiaries/a-1")).toBe(false);
    expect(routes.isCacheableApiPath("/api/v1/tasks")).toBe(true);
  });

  it("recognises route payloads, which are never kept", () => {
    expect(routes.isRoutePayload(new URL("/dashboard?_rsc=1x2y", APP))).toBe(true);
    expect(routes.isRoutePayload(new URL("/dashboard", APP))).toBe(false);
  });

  it("extracts _next/static asset urls", () => {
    const html = `<!DOCTYPE html><html><head>
      <link rel="stylesheet" href="/_next/static/css/app-1a2b.css" data-precedence="next"/>
      <link rel="preload" href="/_next/static/media/inter-3c4d.p.woff2" as="font" crossorigin=""/>
      <script src="/_next/static/chunks/webpack-5e6f.js" async=""></script>
      <script src='/_next/static/chunks/app/page-7a8b.js?dpl=abc' async></script>
      <script src="https://cdn.example/_next/static/chunks/foreign.js"></script>
      <script src="/_next/static/chunks/webpack-5e6f.js" async=""></script>
      </head><body><script>self.__next_f.push([1,"0:[\\"/_next/static/chunks/lazy-9c0d.js\\"]"])</script></body></html>`;

    expect(routes.extractAssetUrls(html).sort()).toEqual([
      "/_next/static/chunks/app/page-7a8b.js?dpl=abc",
      "/_next/static/chunks/lazy-9c0d.js",
      "/_next/static/chunks/webpack-5e6f.js",
      "/_next/static/css/app-1a2b.css",
      "/_next/static/media/inter-3c4d.p.woff2",
    ]);
    expect(routes.extractAssetUrls("<html><body>Keine Assets</body></html>")).toEqual([]);
  });

  it("prunes build assets of old builds, keeping current and recently used ones", () => {
    const now = Date.parse("2026-10-14T12:00:00.000Z");
    const cached = [
      { url: `${APP}/_next/static/chunks/current.js`, date: now - 30 * DAY_MS },
      { url: `${APP}/_next/static/chunks/old.js`, date: now - 8 * DAY_MS },
      { url: `${APP}/_next/static/chunks/recent-lazy.js`, date: now - DAY_MS },
      { url: `${APP}/_next/static/chunks/undated.js`, date: null },
      { url: `${APP}/icon.svg`, date: now - 90 * DAY_MS },
    ];

    expect(
      routes.buildAssetsToPrune(cached, ["/_next/static/chunks/current.js"], now).sort(),
    ).toEqual([`${APP}/_next/static/chunks/old.js`, `${APP}/_next/static/chunks/undated.js`]);
  });

  it("sw.js imports sw-routes.js under its content version, so every change reaches the phones", () => {
    const worker = readFileSync(path.join(PUBLIC_DIR, "sw.js"), "utf8");
    const rules = readFileSync(path.join(PUBLIC_DIR, "sw-routes.js"), "utf8").replace(/\r\n/g, "\n");
    const version = createHash("sha256").update(rules).digest("hex").slice(0, 12);

    expect(worker).toContain(`const SW_ROUTES_VERSION = "${version}";`);
    expect(worker).toContain("importScripts(`/sw-routes.js?v=${SW_ROUTES_VERSION}`);");
  });
});