/**
 * @file Static checks for the Prometheus/Grafana bundle (`monitoring/`,
 * `docker-compose.monitoring.yml`): every YAML and dashboard JSON parses, the
 * compose file mounts paths that exist, and every `agenthub_*` metric a board
 * or recording rule queries is one `server/routes/metrics.js` exports — except
 * `agenthub_cost_usd_total`, which those panels mark as required from another
 * phase. Docker is never run.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

const { it } = require("node:test");
const assert = require("node:assert/strict");
const fs = require("node:fs");
const path = require("node:path");
const yaml = require("js-yaml");

const ROOT = path.resolve(__dirname, "..", "..");
const MON = path.join(ROOT, "monitoring");
const readYaml = (p) => yaml.load(fs.readFileSync(path.join(ROOT, p), "utf8"));
const BOARDS = fs
  .readdirSync(path.join(MON, "grafana", "dashboards"))
  .map((f) => path.join(MON, "grafana", "dashboards", f));

const exported = new Set(
  fs
    .readFileSync(path.join(ROOT, "server", "routes", "metrics.js"), "utf8")
    .match(/"agenthub_[a-z_]+"/g)
    .map((s) => s.slice(1, -1))
);
const OPTIONAL = new Set(["agenthub_cost_usd_total"]);
const metricsIn = (expr) => expr.match(/\bagenthub_[a-z_]+\b/g) || [];

it("compose, Prometheus and provisioning YAML parse and point at real files", () => {
  const compose = readYaml("docker-compose.monitoring.yml");
  assert.deepEqual(Object.keys(compose.services).sort(), ["grafana", "prometheus"]);
  for (const svc of Object.values(compose.services)) {
    for (const v of svc.volumes) {
      const src = v.split(":")[0];
      if (src.startsWith("./")) assert.ok(fs.existsSync(path.join(ROOT, src)), src);
    }
  }
  const prom = readYaml("monitoring/prometheus/prometheus.yml");
  assert.equal(prom.scrape_configs[0].metrics_path, "/api/metrics");
  for (const f of prom.rule_files) assert.ok(fs.existsSync(path.join(MON, "prometheus", f)), f);
  readYaml("monitoring/grafana/provisioning/datasources/datasource.yml");
  readYaml("monitoring/grafana/provisioning/dashboards/provider.yml");
});

it("recording rules query only exported metrics", () => {
  const rules = readYaml("monitoring/prometheus/agenthub-rules.yml");
  const all = rules.groups.flatMap((g) => g.rules);
  assert.ok(all.length > 0);
  for (const r of all) {
    assert.match(r.record, /^agenthub:/);
    for (const m of metricsIn(r.expr))
      assert.ok(exported.has(m) || OPTIONAL.has(m), `${r.record}: ${m}`);
  }
});

it("three boards: valid JSON, unique uid and panel ids, exported metrics only", () => {
  assert.equal(BOARDS.length, 3);
  const uids = new Set();
  let costPanels = 0;
  for (const file of BOARDS) {
    const b = JSON.parse(fs.readFileSync(file, "utf8"));
    assert.ok(b.uid && !uids.has(b.uid), file);
    uids.add(b.uid);
    const ids = b.panels.map((p) => p.id);
    assert.equal(new Set(ids).size, ids.length, `${file}: duplicate panel id`);
    for (const p of b.panels) {
      assert.equal(p.datasource.uid, "${ds}");
      for (const t of p.targets) {
        for (const m of metricsIn(t.expr)) {
          assert.ok(exported.has(m) || OPTIONAL.has(m), `${b.uid} / ${p.title}: ${m}`);
          if (OPTIONAL.has(m)) {
            assert.match(p.description || "", /Requires agenthub_cost_usd_total/, p.title);
            costPanels++;
          }
        }
      }
    }
  }
  assert.ok(costPanels >= 4, "cost panels present");
});