import assert from "node:assert/strict";
import { test } from "node:test";
import { viewWaitsFinding } from "@novox/mesh-sdk/views";
import { CatalogView, REVISION_VERB, findingValue, revisionAnswer, unansweredFinding } from "../catalog.ts";

// Design 47 *Every part takes a first view, then follows the events*: the forge module asks the seat mesh-catalog's verb
// `revision` for the catalog half (every page of one trunk revision), then hears its event `catalog-revision`. A candidate's
// revision moves nothing; a newer trunk revision is waited for, said, and asked; waited for past the bound, view-waits is
// written, and cleared once held; an owner that does not answer is asked again and raised past its bound.

const entry = (module: string, repository: string) => ({ module, repository, dir: ".", manifest: "m", fingerprint: "f", verdict: "accepted" });
const revisionOf = (revision: number, kind = "trunk") => ({ revision, kind, source: revision, entries: [] });

/** A holder of the seat whose trunk revisions are pages of entries, and who answers what is asked of it. */
function aHolder() {
  const asked: Record<string, unknown>[] = [];
  const trunk = new Map<number, { module: string; repository: string }[][]>([
    [7, [[entry("a", "u/a"), entry("b", "u/b")], [entry("c", "u/c")]]],
    [8, [[entry("a", "u/a"), entry("c", "u/c2")]]],
  ]);
  let newest = 7;
  let down = 0;
  return {
    asked,
    set newest(n: number) { newest = n; },
    set down(n: number) { down = n; },
    ask: async (verb: string, input: { after?: string; revision?: number }) => {
      assert.equal(verb, REVISION_VERB);
      asked.push({ ...input });
      if (down > 0) { down--; return { error: "no responders" }; }
      const rev = input.revision ?? newest;
      const pages = trunk.get(rev)!;
      const at = input.after ? pages.findIndex((p) => p[0].module > input.after!) : 0;
      return { revision: revisionOf(rev), entries: pages[at], ...(at < pages.length - 1 ? { next: pages[at].at(-1)!.module } : {}) };
    },
  };
}

test("the catalog view takes the trunk's first view page by page, then a newer trunk revision, and a candidate's moves nothing", async () => {
  const holder = aHolder();
  const changes: string[] = [];
  const view = new CatalogView(holder.ask, { pause: async () => {}, changed: (k, v, deleted) => { changes.push(deleted ? `-${k}` : `${k}=${(v as any).repository}`); } });
  await view.follower.start();
  assert.deepEqual(holder.asked, [{}, { after: "b", revision: 7 }], "the second page names the first page's revision");
  assert.deepEqual([view.held, view.follower.status().view, changes.sort()], [7, "7", ["a=u/a", "b=u/b", "c=u/c"]]);
  const rows: { name: string; ev: Record<string, unknown>; asks: number; held: number }[] = [
    { name: "a candidate's revision", ev: { v: 1, kind: "candidate", revision: 9, source: 8, group: "g", heads: "h" }, asks: 0, held: 7 },
    { name: "the revision it holds", ev: { v: 1, kind: "trunk", revision: 7, source: 7 }, asks: 0, held: 7 },
    { name: "a newer trunk revision", ev: { v: 1, kind: "trunk", revision: 8, source: 8 }, asks: 1, held: 8 },
  ];
  for (const r of rows) {
    holder.newest = 8;
    holder.asked.splice(0);
    changes.splice(0);
    await view.hear(r.ev as any);
    await view.asked;
    assert.deepEqual([holder.asked.length, view.held], [r.asks, r.held], r.name);
  }
  assert.deepEqual(changes.sort(), ["-b", "c=u/c2"], "the newer revision hands what changed");
  const s = view.follower.status();
  assert.deepEqual([s.view, s["waits-for"]], ["8", undefined], "it holds what it waited for");
  await assert.rejects(view.hear({ v: 1, kind: "trunk" } as any), /not a mesh-catalog.catalog-revision event/);
  assert.throws(() => revisionAnswer({ error: "refused for gitea" }), /answered no revision: refused for gitea/);
});

test("a revision waited for past the bound writes view-waits, cleared once held; an unanswered first view is raised, then cleared", async () => {
  const holder = aHolder();
  const said: string[] = [];
  let bound = () => {};
  let clock = 0;
  const view = new CatalogView(holder.ask, {
    pause: () => new Promise((r) => setImmediate(r)), bound: 1000, now: () => new Date(Date.parse("2026-11-09T22:00:00Z") + (clock += 600)),
    waitsBound: () => new Promise<void>((r) => (bound = r)),
    raise: (s) => { said.push(`raised ${findingValue(unansweredFinding("gitea", s, new Date())).key}`); },
    clear: () => { said.push("cleared"); },
    raiseWaits: (s) => { said.push(`waits ${findingValue(viewWaitsFinding("gitea", s, new Date())).key}`); },
    clearWaits: () => { said.push("waits cleared"); },
  });
  holder.down = 3;
  await view.follower.start();
  assert.deepEqual(said, ["raised module.gitea.mesh-catalog.catalog-revisions.first-view-unanswered", "cleared"]);
  said.splice(0);
  holder.newest = 8;
  holder.down = 100; // the holder is away when the newer revision is said
  const heard = view.hear({ v: 1, kind: "trunk", revision: 8, source: 8 } as any);
  await heard;
  assert.equal(view.follower.status()["waits-for"], "8", "it says what it waits for");
  bound();
  await new Promise((r) => setImmediate(r));
  assert.deepEqual(said.filter((l) => l.startsWith("waits")), ["waits module.gitea.mesh-catalog.catalog-revisions.view-waits"]);
  holder.down = 0;
  await view.follower.gap("the holder is back");
  await view.asked;
  assert.deepEqual([view.held, view.follower.status()["waits-for"], said.includes("waits cleared")], [8, undefined, true]);
});