interface TimingSample {
  label: string;
  method: string;
  url: string;
  ok: boolean;
  status: number;
  durationMs: number;
  bytes: number;
  error: string | null;
}

type JsonValue = string | number | boolean | null | JsonValue[] | { [key: string]: JsonValue };

interface CandidateTask {
  id: string;
  status: string;
  stepCount: number | null;
  updatedAt: string;
}

interface TraceCandidate {
  seq: number | null;
  total: number | null;
  durationMs: number;
  error: string | null;
}

interface PerfCheck {
  name: string;
  ok: boolean;
  valueMs: number;
  budgetMs: number;
  hard: boolean;
}

export {};

function envNumber(name: string, fallback: number): number {
  const raw = process.env[name];
  if (raw === undefined || raw.length === 0) return fallback;
  const value = Number(raw);
  if (!Number.isFinite(value) || value <= 0) throw new Error(`${name} must be a positive number`);
  return Math.floor(value);
}

function baseUrl(): string {
  return (process.env.CI_CODE_QUEUE_URL ?? "http://code-queue-ci-read.unidesk-ci.svc.cluster.local:4222").replace(/\/+$/u, "");
}

function terminalStatus(status: string): boolean {
  return status === "succeeded" || status === "failed" || status === "canceled";
}

async function fetchSample(label: string, url: string, timeoutMs = 30_000): Promise<TimingSample> {
  const started = performance.now();
  try {
    const response = await fetch(url, { signal: AbortSignal.timeout(timeoutMs) });
    const text = await response.text();
    return {
      label,
      method: "GET",
      url,
      ok: response.ok,
      status: response.status,
      durationMs: Math.round((performance.now() - started) * 10) / 10,
      bytes: text.length,
      error: null,
    };
  } catch (error) {
    return {
      label,
      method: "GET",
      url,
      ok: false,
      status: 0,
      durationMs: Math.round((performance.now() - started) * 10) / 10,
      bytes: 0,
      error: error instanceof Error ? error.message : String(error),
    };
  }
}

function percentile(values: number[], percentileValue: number): number {
  if (values.length === 0) return 0;
  const sorted = values.slice().sort((left, right) => left - right);
  if (percentileValue <= 0) return sorted[0] ?? 0;
  if (percentileValue >= 100) return sorted[sorted.length - 1] ?? 0;
  const index = Math.min(sorted.length - 1, Math.max(0, Math.ceil((percentileValue / 100) * sorted.length) - 1));
  return sorted[index] ?? 0;
}

async function candidateTasks(url: string): Promise<CandidateTask[]> {
  const response = await fetch(`${url}/api/tasks/overview?limit=48&transcriptLimit=0&compact=1&selected=0&includeActive=0&stats=0&skipTrace=1`, {
    signal: AbortSignal.timeout(30_000),
  });
  const body = await response.json() as { tasks?: Array<{ id?: string; status?: string; stepCount?: number; llmStepCount?: number; updatedAt?: string }> };
  const tasks = (body.tasks ?? [])
    .map((task): CandidateTask | null => {
      if (typeof task.id !== "string" || task.id.length === 0) return null;
      const stepCount = Number(task.stepCount ?? task.llmStepCount);
      return {
        id: task.id,
        status: typeof task.status === "string" ? task.status : "",
        stepCount: Number.isFinite(stepCount) && stepCount >= 0 ? Math.floor(stepCount) : null,
        updatedAt: typeof task.updatedAt === "string" ? task.updatedAt : "",
      };
    })
    .filter((task): task is CandidateTask => task !== null);
  const ordered = [
    ...tasks.filter((task) => terminalStatus(task.status) && (task.stepCount ?? 0) > 0 && (task.stepCount ?? 0) <= 300),
    ...tasks.filter((task) => terminalStatus(task.status) && ((task.stepCount ?? 0) === 0 || task.stepCount === null)),
    ...tasks.filter((task) => terminalStatus(task.status)),
    ...tasks.filter((task) => !terminalStatus(task.status) && task.status !== "queued" && task.status !== "running" && task.status !== "judging"),
  ];
  const seen = new Set<string>();
  return ordered.filter((task) => {
    if (seen.has(task.id)) return false;
    seen.add(task.id);
    return true;
  });
}

async function traceSeq(url: string, taskId: string, timeoutMs: number): Promise<TraceCandidate> {
  const started = performance.now();
  try {
    const response = await fetch(`${url}/api/tasks/${encodeURIComponent(taskId)}/trace-steps?tail=1&limit=1`, {
      signal: AbortSignal.timeout(timeoutMs),
    });
    const body = await response.json() as { total?: number; steps?: Array<{ seq?: number }> };
    const durationMs = Math.round((performance.now() - started) * 10) / 10;
    if (!response.ok) return { seq: null, total: null, durationMs, error: `status=${response.status}` };
    const seq = body.steps?.find((step) => Number.isFinite(Number(step.seq)))?.seq;
    return {
      seq: Number.isFinite(Number(seq)) ? Number(seq) : null,
      total: Number.isFinite(Number(body.total)) ? Number(body.total) : null,
      durationMs,
      error: null,
    };
  } catch (error) {
    return {
      seq: null,
      total: null,
      durationMs: Math.round((performance.now() - started) * 10) / 10,
      error: error instanceof Error ? error.message : String(error),
    };
  }
}

async function traceTarget(url: string): Promise<{ taskId: string; skippedTaskIds: string[]; selection: JsonValue }> {
  const tasks = await candidateTasks(url);
  if (tasks.length === 0) throw new Error("Code Queue CI perf could not find a terminal task id in the production PostgreSQL task table");
  const target = tasks[0];
  if (target === undefined) throw new Error("Code Queue CI perf could not select a task from the production PostgreSQL task table");
  return { taskId: target.id, skippedTaskIds: tasks.slice(1).map((task) => task.id), selection: target as unknown as JsonValue };
}

async function measureFirstPaint(url: string): Promise<Record<string, unknown>> {
  const sample = await fetchSample("code-queue-read-first-paint-proxy", `${url}/api/tasks/overview?limit=12&transcriptLimit=1&compact=1&selected=0&includeActive=0&stats=0&skipTrace=1`, 60_000);
  return {
    ok: sample.ok,
    url: sample.url,
    firstPaintMs: sample.durationMs,
    apiTimings: [sample],
    consoleErrors: [],
    note: "Code Queue service is API-only in k3s; this measures the first overview payload used by the frontend Code Queue page.",
  };
}

async function main(): Promise<void> {
  const url = baseUrl();
  const budgets = {
    firstPaintMs: envNumber("FIRST_PAINT_BUDGET_MS", 2000),
    traceSummaryMs: envNumber("TRACE_SUMMARY_BUDGET_MS", 10_000),
    traceStepsMs: envNumber("TRACE_STEPS_BUDGET_MS", 900),
    traceStepDetailMs: envNumber("TRACE_STEP_DETAIL_BUDGET_MS", 700),
    overviewP95Ms: envNumber("OVERVIEW_P95_BUDGET_MS", 900),
  };
  const health = await fetchSample("health", `${url}/health`);
  if (!health.ok) throw new Error(`Code Queue CI read health failed: ${JSON.stringify(health)}`);
  const target = await traceTarget(url);
  const { taskId } = target;
  const firstPaint = await measureFirstPaint(url);
  const traceSummary = await fetchSample("trace-summary", `${url}/api/tasks/${encodeURIComponent(taskId)}/trace-summary`);
  const overviewSamples: TimingSample[] = [];
  for (let index = 0; index < 10; index += 1) {
    overviewSamples.push(await fetchSample("overview", `${url}/api/tasks/overview?limit=12&transcriptLimit=1&compact=1&selected=0&includeActive=0&stats=0&skipTrace=1&__ci=${Date.now()}-${index}`));
  }
  const traceProbe = await traceSeq(url, taskId, Math.max(10_000, Math.min(30_000, budgets.traceStepsMs)));
  const seq = traceProbe.seq ?? 0;
  const traceSteps = await fetchSample("trace-steps", `${url}/api/tasks/${encodeURIComponent(taskId)}/trace-steps?tail=1&limit=1`, Math.max(10_000, Math.min(30_000, budgets.traceStepsMs)));
  const traceStepDetail = seq > 0
    ? await fetchSample("trace-step-detail", `${url}/api/tasks/${encodeURIComponent(taskId)}/trace-step?seq=${encodeURIComponent(String(seq))}`, Math.max(10_000, Math.min(30_000, budgets.traceStepDetailMs)))
    : {
      label: "trace-step-detail",
      method: "GET",
      url: `${url}/api/tasks/${encodeURIComponent(taskId)}/trace-step?seq=0`,
      ok: false,
      status: 0,
      durationMs: 0,
      bytes: 0,
      error: traceProbe.error ?? "trace step seq unavailable",
    };
  const overviewSuccessful = overviewSamples.filter((sample) => sample.ok).map((sample) => sample.durationMs);
  const overviewP95Ms = Math.round(percentile(overviewSuccessful, 95) * 10) / 10;
  const firstPaintMs = Number((firstPaint as { firstPaintMs?: number }).firstPaintMs ?? 0);
  const checks: PerfCheck[] = [
    { name: "first-paint", ok: firstPaintMs <= budgets.firstPaintMs, valueMs: firstPaintMs, budgetMs: budgets.firstPaintMs, hard: true },
    { name: "trace-summary", ok: traceSummary.ok && traceSummary.durationMs <= budgets.traceSummaryMs, valueMs: traceSummary.durationMs, budgetMs: budgets.traceSummaryMs, hard: true },
    { name: "overview-p95", ok: overviewSamples.every((sample) => sample.ok) && overviewP95Ms <= budgets.overviewP95Ms, valueMs: overviewP95Ms, budgetMs: budgets.overviewP95Ms, hard: true },
    { name: "trace-steps", ok: traceSteps.ok && traceSteps.durationMs <= budgets.traceStepsMs, valueMs: traceSteps.durationMs, budgetMs: budgets.traceStepsMs, hard: false },
    { name: "trace-step-detail", ok: traceStepDetail.ok && traceStepDetail.durationMs <= budgets.traceStepDetailMs, valueMs: traceStepDetail.durationMs, budgetMs: budgets.traceStepDetailMs, hard: false },
  ];
  const hardChecks = checks.filter((check) => check.hard);
  const result = {
    ok: hardChecks.every((check) => check.ok),
    measuredAt: new Date().toISOString(),
    url,
    taskId,
    seq,
    skippedTaskIds: target.skippedTaskIds,
    selection: target.selection,
    budgets,
    checks,
    diagnostics: {
      nonBlockingChecks: checks.filter((check) => !check.hard).map((check) => check.name),
      traceProbe,
    },
    health,
    firstPaint,
    traceSummary,
    traceSteps,
    traceStepDetail,
    overview: {
      p50Ms: Math.round(percentile(overviewSuccessful, 50) * 10) / 10,
      p95Ms: overviewP95Ms,
      samples: overviewSamples,
    },
  };
  console.log(JSON.stringify(result, null, 2));
  if (!result.ok) process.exitCode = 1;
}

await main();