// gitea's events. The tool runtime imports this once the broker is bound. It watches the forge and
// emits what appeared.
//
// Emits (novox/hq ADR 0041/0042):
//   module.gitea.repo.created   — a repository appeared, however it was made (push, web UI, or tool)
//
// issue.opened and pull.merged are emitted from the tools (tools/index.ts), at the instant the mesh
// takes that action — the natural point, and one process only. repo.created belongs here instead:
// a repository is usually born from a `git push` or the web UI, which no tool sees, so polling the
// repo list is the only way to catch every path — and keeping it out of the create-repo tool means
// the fact is never announced twice from two processes.
//
// The polling is deliberately unhurried: an event a minute late is still an event, whereas hammering
// the forge for an immediacy nobody asked for is not.

import { emit } from "@novox/mesh-sdk/events";
import { GiteaClient } from "./client.js";

// Without a way to a token — configured, or mintable with the admin account (token.ts) — there is
// nothing to watch; log and stay quiet rather than crash the runtime. With one, the first poll mints
// or reuses the token, so the runtime's start also shows what it did about it.
let gitea: GiteaClient | null = null;
try {
  gitea = GiteaClient.fromEnv();
} catch (err) {
  console.log(`[gitea] not watching — ${err instanceof Error ? err.message : String(err)}`);
}

// New repositories, by diffing the repo list. Primed silently on the first look, or a restart would
// re-announce every existing repository as freshly created.
const seen = new Set<string>();
let primed = false;
async function pollRepos(client: GiteaClient): Promise<void> {
  const repos = await client.listAllRepos();
  for (const repo of repos) {
    if (!seen.has(repo.full_name)) {
      if (primed) {
        await emit("repo.created", {
          full_name: repo.full_name,
          owner: repo.owner,
          name: repo.name,
          private: repo.private,
          html_url: repo.html_url,
        });
      }
      seen.add(repo.full_name);
    }
  }
  primed = true;
}

// **A merge is announced whoever made it.** The merge tool below emits at the instant it acts; a
// merge made in the forge's own pages or over its API would emit nothing, and the mesh would go on
// believing every module current with its source (novox/hq 04-ISSUES/131). So merged pull requests
// are watched the way repositories are: what the forge holds, asked for on a tick, announced once.
// What has been announced is kept beside the module's state, so a restart does not announce the
// whole history again — and the first tick on a machine with no record announces nothing, because
// everything it sees then predates the watching.
import { existsSync, mkdirSync, readFileSync, renameSync, writeFileSync } from "node:fs";
import { join } from "node:path";
const mergedRecord = process.env.MESH_GITEA_STATE_DIR ? join(process.env.MESH_GITEA_STATE_DIR, "merged-announced.json") : null;
const announced = new Set<string>();
let primedMerges = false;
// since is the moment the watching began: a merge made before it is history, whatever page of the
// forge's listing it surfaces on. Without it, an old merge past the first page — pushed into view
// as newer pull requests were updated — was announced as if it had just happened, and the mesh
// rebuilt everything built from that repository, once per old merge (2026-09-28).
let since = "";
if (mergedRecord && existsSync(mergedRecord)) {
  try {
    const kept = JSON.parse(readFileSync(mergedRecord, "utf8")) as string[] | { announced: string[]; since: string };
    const list = Array.isArray(kept) ? kept : kept.announced;
    for (const sha of list) announced.add(sha);
    since = Array.isArray(kept) ? new Date().toISOString() : kept.since;
    primedMerges = true;
  } catch {
    // An unreadable record is treated as no record: prime again rather than re-announce history.
  }
}
function keepAnnounced(): void {
  if (!mergedRecord) return;
  mkdirSync(join(mergedRecord, ".."), { recursive: true });
  const tmp = mergedRecord + ".tmp";
  writeFileSync(tmp, JSON.stringify({ announced: [...announced].slice(-2000), since }));
  renameSync(tmp, mergedRecord);
}
async function pollMerged(client: GiteaClient): Promise<void> {
  const repos = await client.listAllRepos();
  let changed = false;
  for (const repo of repos) {
    const pulls = await client.listPullRequests(repo.owner, repo.name, { state: "closed", sort: "recentupdate", limit: "20" });
    for (const pull of pulls) {
      if (!pull.merged || !pull.merge_commit_sha || announced.has(pull.merge_commit_sha)) continue;
      // Announced only if merged since the watching began; recorded either way, so it is looked
      // at once.
      const fresh = !!pull.merged_at && !!since && pull.merged_at > since;
      if (primedMerges && fresh) {
        // What it changed, asked for only now: a module is rebuilt because a file inside its own
        // directory moved, and without this every module built from a repository is rebuilt for a
        // change to any of them (novox/hq 04-ISSUES/131).
        const changed = await client.listPullFiles(repo.owner, repo.name, pull.number);
        await emit("pull.merged", {
          owner: repo.owner,
          repo: repo.name,
          number: pull.number,
          title: pull.title,
          head: pull.head,
          base: pull.base,
          merge_commit_sha: pull.merge_commit_sha,
          merged_at: pull.merged_at,
          clone_url: repo.clone_url,
          html_url: pull.html_url,
          paths: changed.paths,
          paths_truncated: changed.truncated,
        });
        // Said, because a trigger that fires silently is indistinguishable from one that did not
        // fire (novox/hq 04-ISSUES/131) — this line is how an operator knows the mesh was told.
        console.log(`[gitea] announced merge ${repo.full_name}#${pull.number} (${pull.merge_commit_sha.slice(0, 8)}) into ${pull.base}`);
      }
      announced.add(pull.merge_commit_sha);
      changed = true;
    }
  }
  if (!primedMerges) since = new Date().toISOString();
  if (!primedMerges || changed) keepAnnounced();
  primedMerges = true;
}

if (gitea) {
  const client = gitea;
  // A poll that fails says so once, not once a minute: the same reason repeating (the forge not up
  // yet, the admin account refused on a restored forge) is one fact, and a recovery is worth a line.
  let failing: string | null = null;
  const tick = (fn: () => Promise<void>, everyMs: number): void => {
    const run = (): void =>
      void fn()
        .then(() => {
          if (failing !== null) console.log("[gitea] watching again");
          failing = null;
        })
        .catch((err) => {
          const why = err instanceof Error ? err.message : String(err);
          if (why !== failing) console.error(`[gitea] not watching until this clears — ${why}`);
          failing = why;
        });
    setInterval(run, everyMs);
    run();
  };
  tick(() => pollRepos(client), 60_000);
  tick(() => pollMerged(client), 30_000);
  console.log("[gitea] watching for new repositories and merged pull requests");
}