#!/usr/bin/env python3
  """
  API-level performance test script for search stack services.
  
  Default scenarios (aligned with docs/搜索API对接指南.md):
  - backend_search      POST /search/
  - backend_suggest     GET  /search/suggestions
  - embed_text          POST /embed/text
  - translate           POST /translate
  - rerank              POST /rerank
  
  Examples:
    python scripts/perf_api_benchmark.py --scenario backend_search --duration 30 --concurrency 20 --tenant-id 162
    python scripts/perf_api_benchmark.py --scenario backend_suggest --duration 30 --concurrency 50 --tenant-id 162
    python scripts/perf_api_benchmark.py --scenario all --duration 60 --concurrency 80 --tenant-id 162
    python scripts/perf_api_benchmark.py --scenario all --cases-file scripts/perf_cases.json.example --output perf_result.json
  """
  
  from __future__ import annotations
  
  import argparse
  import asyncio
  import json
  import math

  import random

  import statistics
  import time
  from dataclasses import dataclass
  from pathlib import Path
  from typing import Any, Dict, List, Optional, Tuple
  
  import httpx
  
  
  @dataclass
  class RequestTemplate:
      method: str
      path: str
      params: Optional[Dict[str, Any]] = None
      json_body: Optional[Any] = None
      headers: Optional[Dict[str, str]] = None
  
  
  @dataclass
  class Scenario:
      name: str
      templates: List[RequestTemplate]
      timeout_sec: float
  
  
  @dataclass
  class RequestResult:
      ok: bool
      status_code: int
      latency_ms: float
      error: str = ""
  
  

  def _is_finite_number(v: Any) -> bool:
      if isinstance(v, bool):
          return False
      if isinstance(v, (int, float)):
          return math.isfinite(float(v))
      return False
  
  
  def validate_response_payload(
      scenario_name: str,
      tpl: RequestTemplate,
      payload: Any,
  ) -> Tuple[bool, str]:
      """
      Lightweight payload validation for correctness-aware perf tests.
      Currently strict for embed_text to catch NaN/null vector regressions.
      """
      if scenario_name != "embed_text":
          return True, ""
  
      expected_len = len(tpl.json_body) if isinstance(tpl.json_body, list) else None
      if not isinstance(payload, list):
          return False, "invalid_payload_non_list"
      if expected_len is not None and len(payload) != expected_len:
          return False, "invalid_payload_length"
      if len(payload) == 0:
          return False, "invalid_payload_empty"
  
      for i, vec in enumerate(payload):
          if not isinstance(vec, list) or len(vec) == 0:
              return False, f"invalid_vector_{i}_shape"
          for x in vec:
              if not _is_finite_number(x):
                  return False, f"invalid_vector_{i}_non_finite"
      return True, ""
  
  

  def percentile(sorted_values: List[float], p: float) -> float:
      if not sorted_values:
          return 0.0
      if p <= 0:
          return sorted_values[0]
      if p >= 100:
          return sorted_values[-1]
      rank = (len(sorted_values) - 1) * (p / 100.0)
      low = int(math.floor(rank))
      high = int(math.ceil(rank))
      if low == high:
          return sorted_values[low]
      weight = rank - low
      return sorted_values[low] * (1.0 - weight) + sorted_values[high] * weight
  
  
  def make_default_templates(tenant_id: str) -> Dict[str, List[RequestTemplate]]:
      return {
          "backend_search": [
              RequestTemplate(
                  method="POST",
                  path="/search/",
                  headers={"X-Tenant-ID": tenant_id},
                  json_body={"query": "wireless mouse", "size": 10, "language": "en"},
              ),
              RequestTemplate(
                  method="POST",
                  path="/search/",
                  headers={"X-Tenant-ID": tenant_id},
                  json_body={"query": "芭比娃娃", "size": 10, "language": "zh"},
              ),
              RequestTemplate(
                  method="POST",
                  path="/search/",
                  headers={"X-Tenant-ID": tenant_id},
                  json_body={"query": "f", "size": 10, "language": "en"},
              ),
          ],
          "backend_suggest": [
              RequestTemplate(
                  method="GET",
                  path="/search/suggestions",
                  headers={"X-Tenant-ID": tenant_id},
                  params={"q": "f", "size": 10, "language": "en"},
              ),
              RequestTemplate(
                  method="GET",
                  path="/search/suggestions",
                  headers={"X-Tenant-ID": tenant_id},
                  params={"q": "玩", "size": 10, "language": "zh"},
              ),
              RequestTemplate(
                  method="GET",
                  path="/search/suggestions",
                  headers={"X-Tenant-ID": tenant_id},
                  params={"q": "shi", "size": 10, "language": "en"},
              ),
          ],
          "embed_text": [
              RequestTemplate(
                  method="POST",
                  path="/embed/text",
                  json_body=["wireless mouse", "gaming keyboard", "barbie doll"],
              )
          ],
          "translate": [
              RequestTemplate(
                  method="POST",
                  path="/translate",
                  json_body={"text": "商品名称", "target_lang": "en", "source_lang": "zh", "model": "qwen"},
              ),
              RequestTemplate(
                  method="POST",
                  path="/translate",
                  json_body={"text": "Product title", "target_lang": "zh", "model": "qwen"},
              ),
          ],
          "rerank": [
              RequestTemplate(
                  method="POST",
                  path="/rerank",
                  json_body={
                      "query": "wireless mouse",
                      "docs": [
                          "Wireless ergonomic mouse with rechargeable battery",
                          "USB-C cable 1m",
                          "Gaming mouse 26000 DPI",
                      ],
                      "normalize": True,
                  },
              )
          ],
      }
  
  
  def load_cases_from_file(path: Path, tenant_id: str) -> Dict[str, List[RequestTemplate]]:
      data = json.loads(path.read_text(encoding="utf-8"))
      out: Dict[str, List[RequestTemplate]] = {}
      for scenario_name, requests_data in (data.get("scenarios") or {}).items():
          templates: List[RequestTemplate] = []
          for item in requests_data:
              headers = dict(item.get("headers") or {})
              if "X-Tenant-ID" in headers and str(headers["X-Tenant-ID"]).strip() == "${tenant_id}":
                  headers["X-Tenant-ID"] = tenant_id
              templates.append(
                  RequestTemplate(
                      method=str(item.get("method", "GET")).upper(),
                      path=str(item.get("path", "")).strip(),
                      params=item.get("params"),
                      json_body=item.get("json"),
                      headers=headers or None,
                  )
              )
          if templates:
              out[scenario_name] = templates
      return out
  
  
  def build_scenarios(args: argparse.Namespace) -> Dict[str, Scenario]:
      defaults = make_default_templates(args.tenant_id)
      if args.cases_file:
          custom = load_cases_from_file(Path(args.cases_file), tenant_id=args.tenant_id)
          defaults.update(custom)
  
      scenario_base = {
          "backend_search": args.backend_base,
          "backend_suggest": args.backend_base,
          "embed_text": args.embedding_base,
          "translate": args.translator_base,
          "rerank": args.reranker_base,
      }
  
      scenarios: Dict[str, Scenario] = {}
      for name, templates in defaults.items():
          if name not in scenario_base:
              continue
          base = scenario_base[name].rstrip("/")
          rewritten: List[RequestTemplate] = []
          for t in templates:
              path = t.path if t.path.startswith("/") else f"/{t.path}"
              rewritten.append(
                  RequestTemplate(
                      method=t.method,
                      path=f"{base}{path}",
                      params=t.params,
                      json_body=t.json_body,
                      headers=t.headers,
                  )
              )
          scenarios[name] = Scenario(name=name, templates=rewritten, timeout_sec=args.timeout)
      return scenarios
  
  
  async def run_single_scenario(
      scenario: Scenario,
      duration_sec: int,
      concurrency: int,
      max_requests: int,
      max_errors: int,

      rerank_dynamic_cfg: Optional[Dict[str, Any]] = None,

  ) -> Dict[str, Any]:
      latencies: List[float] = []
      status_counter: Dict[int, int] = {}
      err_counter: Dict[str, int] = {}
      total_requests = 0
      success_requests = 0
      stop_flag = False
      lock = asyncio.Lock()
      start = time.perf_counter()
  
      timeout = httpx.Timeout(timeout=scenario.timeout_sec)
      limits = httpx.Limits(max_connections=max(concurrency * 2, 20), max_keepalive_connections=max(concurrency, 10))
  
      async def worker(worker_id: int, client: httpx.AsyncClient) -> None:
          nonlocal total_requests, success_requests, stop_flag
          idx = worker_id % len(scenario.templates)

          worker_rng: Optional[random.Random] = None
          if rerank_dynamic_cfg is not None:
              worker_rng = random.Random(int(rerank_dynamic_cfg["seed"]) + worker_id)

  
          while not stop_flag:
              elapsed = time.perf_counter() - start
              if duration_sec > 0 and elapsed >= duration_sec:
                  break
  
              async with lock:
                  if max_requests > 0 and total_requests >= max_requests:
                      stop_flag = True
                      break
                  total_requests += 1
  
              tpl = scenario.templates[idx % len(scenario.templates)]
              idx += 1
  
              t0 = time.perf_counter()
              ok = False
              status = 0
              err = ""
              try:

                  req_json_body = tpl.json_body
                  if rerank_dynamic_cfg is not None and worker_rng is not None:
                      req_json_body = build_random_rerank_payload(rerank_dynamic_cfg, worker_rng)

                  resp = await client.request(
                      method=tpl.method,
                      url=tpl.path,
                      params=tpl.params,

                      json=req_json_body,

                      headers=tpl.headers,
                  )
                  status = int(resp.status_code)
                  ok = 200 <= status < 300

                  if ok:
                      try:
                          payload = resp.json()
                      except Exception:
                          ok = False
                          err = "invalid_json_response"
                      else:
                          valid, reason = validate_response_payload(
                              scenario_name=scenario.name,
                              tpl=tpl,
                              payload=payload,
                          )
                          if not valid:
                              ok = False
                              err = reason or "invalid_payload"
                  if not ok and not err:

                      err = f"http_{status}"
              except Exception as e:
                  err = type(e).__name__
              t1 = time.perf_counter()
              cost_ms = (t1 - t0) * 1000.0
  
              async with lock:
                  latencies.append(cost_ms)
                  if status:
                      status_counter[status] = status_counter.get(status, 0) + 1
                  if ok:
                      success_requests += 1
                  else:
                      err_counter[err or "unknown"] = err_counter.get(err or "unknown", 0) + 1
                      total_err = sum(err_counter.values())
                      if max_errors > 0 and total_err >= max_errors:
                          stop_flag = True
  
      async with httpx.AsyncClient(timeout=timeout, limits=limits) as client:
          tasks = [asyncio.create_task(worker(i, client)) for i in range(concurrency)]
          await asyncio.gather(*tasks)
  
      elapsed = max(time.perf_counter() - start, 1e-9)
      lat_sorted = sorted(latencies)
  
      result = {
          "scenario": scenario.name,
          "duration_sec": round(elapsed, 3),
          "total_requests": total_requests,
          "success_requests": success_requests,
          "failed_requests": max(total_requests - success_requests, 0),
          "success_rate": round((success_requests / total_requests) * 100.0, 2) if total_requests else 0.0,
          "throughput_rps": round(total_requests / elapsed, 2),
          "latency_ms": {
              "avg": round(statistics.mean(lat_sorted), 2) if lat_sorted else 0.0,
              "p50": round(percentile(lat_sorted, 50), 2),
              "p90": round(percentile(lat_sorted, 90), 2),
              "p95": round(percentile(lat_sorted, 95), 2),
              "p99": round(percentile(lat_sorted, 99), 2),
              "max": round(max(lat_sorted), 2) if lat_sorted else 0.0,
          },
          "status_codes": dict(sorted(status_counter.items(), key=lambda x: x[0])),
          "errors": dict(sorted(err_counter.items(), key=lambda x: x[0])),
      }
      return result
  
  
  def format_summary(result: Dict[str, Any]) -> str:
      lines = []
      lines.append(f"\\n=== Scenario: {result['scenario']} ===")
      lines.append(
          "requests={total_requests} success={success_requests} fail={failed_requests} "
          "success_rate={success_rate}% rps={throughput_rps}".format(**result)
      )
      lat = result["latency_ms"]
      lines.append(
          f"latency(ms): avg={lat['avg']} p50={lat['p50']} p90={lat['p90']} p95={lat['p95']} p99={lat['p99']} max={lat['max']}"
      )
      lines.append(f"status_codes: {result['status_codes']}")
      if result["errors"]:
          lines.append(f"errors: {result['errors']}")
      return "\\n".join(lines)
  
  
  def aggregate_results(results: List[Dict[str, Any]]) -> Dict[str, Any]:
      if not results:
          return {}
      total_requests = sum(x["total_requests"] for x in results)
      success_requests = sum(x["success_requests"] for x in results)
      failed_requests = sum(x["failed_requests"] for x in results)
      total_duration = sum(x["duration_sec"] for x in results)
      weighted_avg_latency = 0.0
      if total_requests > 0:
          weighted_avg_latency = sum(x["latency_ms"]["avg"] * x["total_requests"] for x in results) / total_requests
  
      return {
          "scenario": "ALL",
          "total_requests": total_requests,
          "success_requests": success_requests,
          "failed_requests": failed_requests,
          "success_rate": round((success_requests / total_requests) * 100.0, 2) if total_requests else 0.0,
          "aggregate_rps": round(total_requests / max(total_duration, 1e-9), 2),
          "weighted_avg_latency_ms": round(weighted_avg_latency, 2),
      }
  
  

  def parse_csv_items(raw: str) -> List[str]:
      return [x.strip() for x in str(raw or "").split(",") if x.strip()]
  
  
  def parse_csv_ints(raw: str) -> List[int]:
      values: List[int] = []
      seen = set()
      for item in parse_csv_items(raw):
          try:
              value = int(item)
          except ValueError as exc:
              raise ValueError(f"Invalid integer in CSV list: {item}") from exc
          if value <= 0:
              raise ValueError(f"Concurrency must be > 0, got {value}")
          if value in seen:
              continue
          seen.add(value)
          values.append(value)
      return values
  
  

  def parse_args() -> argparse.Namespace:
      parser = argparse.ArgumentParser(description="Interface-level load test for search and related microservices")
      parser.add_argument(
          "--scenario",
          type=str,
          default="all",

          help="Scenario: backend_search | backend_suggest | embed_text | translate | rerank | all | comma-separated list",

      )
      parser.add_argument("--tenant-id", type=str, default="162", help="Tenant ID for backend search/suggest")
      parser.add_argument("--duration", type=int, default=30, help="Duration seconds per scenario; <=0 means no duration cap")
      parser.add_argument("--concurrency", type=int, default=20, help="Concurrent workers per scenario")
      parser.add_argument("--max-requests", type=int, default=0, help="Stop after N requests per scenario (0 means unlimited)")
      parser.add_argument("--timeout", type=float, default=10.0, help="Request timeout seconds")
      parser.add_argument("--max-errors", type=int, default=0, help="Stop scenario when accumulated errors reach this value")
  
      parser.add_argument("--backend-base", type=str, default="http://127.0.0.1:6002", help="Base URL for backend search API")
      parser.add_argument("--embedding-base", type=str, default="http://127.0.0.1:6005", help="Base URL for embedding service")
      parser.add_argument("--translator-base", type=str, default="http://127.0.0.1:6006", help="Base URL for translation service")
      parser.add_argument("--reranker-base", type=str, default="http://127.0.0.1:6007", help="Base URL for reranker service")
  
      parser.add_argument("--cases-file", type=str, default="", help="Optional JSON file to override/add request templates")
      parser.add_argument("--output", type=str, default="", help="Optional output JSON path")
      parser.add_argument("--pause", type=float, default=0.0, help="Pause seconds between scenarios in all mode")

      parser.add_argument(
          "--concurrency-list",
          type=str,
          default="",
          help="Comma-separated concurrency list (e.g. 1,5,10,20). If set, overrides --concurrency.",
      )

      parser.add_argument(
          "--rerank-dynamic-docs",
          action="store_true",
          help="For rerank scenario, generate docs payload dynamically on every request.",
      )
      parser.add_argument("--rerank-doc-count", type=int, default=386, help="Doc count per rerank request when dynamic docs are enabled")
      parser.add_argument("--rerank-vocab-size", type=int, default=1000, help="Word pool size for rerank dynamic docs generation")
      parser.add_argument("--rerank-sentence-min-words", type=int, default=15, help="Minimum words per generated doc sentence")
      parser.add_argument("--rerank-sentence-max-words", type=int, default=40, help="Maximum words per generated doc sentence")
      parser.add_argument("--rerank-query", type=str, default="wireless mouse", help="Fixed query used for rerank dynamic docs mode")
      parser.add_argument("--rerank-seed", type=int, default=20260312, help="Base random seed for rerank dynamic docs mode")

      return parser.parse_args()
  
  

  def build_rerank_dynamic_cfg(args: argparse.Namespace) -> Dict[str, Any]:
      min_words = int(args.rerank_sentence_min_words)
      max_words = int(args.rerank_sentence_max_words)
      doc_count = int(args.rerank_doc_count)
      vocab_size = int(args.rerank_vocab_size)
      if doc_count <= 0:
          raise ValueError(f"rerank-doc-count must be > 0, got {doc_count}")
      if vocab_size <= 0:
          raise ValueError(f"rerank-vocab-size must be > 0, got {vocab_size}")
      if min_words <= 0:
          raise ValueError(f"rerank-sentence-min-words must be > 0, got {min_words}")
      if max_words < min_words:
          raise ValueError(
              f"rerank-sentence-max-words must be >= rerank-sentence-min-words, got {max_words} < {min_words}"
          )
      if args.rerank_seed < 0:
          raise ValueError(f"rerank-seed must be >= 0, got {args.rerank_seed}")
  
      # Use deterministic, letter-only pseudo words to avoid long tokenization of numeric strings.
      syllables = [
          "al", "an", "ar", "as", "at", "ba", "be", "bi", "bo", "ca",
          "ce", "ci", "co", "da", "de", "di", "do", "el", "en", "er",
          "fa", "fe", "fi", "fo", "ga", "ge", "gi", "go", "ha", "he",
          "hi", "ho", "ia", "ie", "il", "in", "io", "is", "ka", "ke",
          "ki", "ko", "la", "le", "li", "lo", "ma", "me", "mi", "mo",
      ]
      word_pool: List[str] = []
      for a in syllables:
          for b in syllables:
              word_pool.append(f"{a}{b}")
              if len(word_pool) >= vocab_size:
                  break
          if len(word_pool) >= vocab_size:
              break
      if len(word_pool) < vocab_size:
          raise ValueError(f"Unable to generate enough synthetic words: requested={vocab_size}, got={len(word_pool)}")
      return {
          "query": args.rerank_query,
          "doc_count": doc_count,
          "min_words": min_words,
          "max_words": max_words,
          "seed": int(args.rerank_seed),
          "normalize": True,
          "word_pool": word_pool,
      }
  
  
  def build_random_rerank_payload(
      cfg: Dict[str, Any],
      rng: random.Random,
  ) -> Dict[str, Any]:
      word_pool: List[str] = cfg["word_pool"]
      docs = []
      for _ in range(cfg["doc_count"]):
          doc_len = rng.randint(cfg["min_words"], cfg["max_words"])
          docs.append(" ".join(rng.choices(word_pool, k=doc_len)))
      return {
          "query": cfg["query"],
          "docs": docs,
          "normalize": bool(cfg.get("normalize", True)),
      }
  
  

  async def main_async() -> int:
      args = parse_args()
      scenarios = build_scenarios(args)
  
      all_names = ["backend_search", "backend_suggest", "embed_text", "translate", "rerank"]
      if args.scenario == "all":
          run_names = [x for x in all_names if x in scenarios]
      else:

          requested = parse_csv_items(args.scenario)
          if not requested:
              print("No scenario specified.")
              return 2
          unknown = [name for name in requested if name not in scenarios]
          if unknown:
              print(f"Unknown scenario(s): {', '.join(unknown)}")

              print(f"Available: {', '.join(sorted(scenarios.keys()))}")
              return 2

          run_names = requested

  
      if not run_names:
          print("No scenarios to run.")
          return 2
  

      rerank_dynamic_cfg: Optional[Dict[str, Any]] = None
      if args.rerank_dynamic_docs:
          try:
              rerank_dynamic_cfg = build_rerank_dynamic_cfg(args)
          except ValueError as exc:
              print(str(exc))
              return 2
  

      concurrency_values = [args.concurrency]
      if args.concurrency_list:
          try:
              concurrency_values = parse_csv_ints(args.concurrency_list)
          except ValueError as exc:
              print(str(exc))
              return 2
          if not concurrency_values:
              print("concurrency-list is empty after parsing.")
              return 2
  

      print("Load test config:")
      print(f"  scenario={args.scenario}")
      print(f"  tenant_id={args.tenant_id}")
      print(f"  duration={args.duration}s")
      print(f"  concurrency={args.concurrency}")

      print(f"  concurrency_list={concurrency_values}")

      print(f"  max_requests={args.max_requests}")
      print(f"  timeout={args.timeout}s")
      print(f"  max_errors={args.max_errors}")
      print(f"  backend_base={args.backend_base}")
      print(f"  embedding_base={args.embedding_base}")
      print(f"  translator_base={args.translator_base}")
      print(f"  reranker_base={args.reranker_base}")

      if args.rerank_dynamic_docs:
          print("  rerank_dynamic_docs=True")
          print(f"  rerank_doc_count={args.rerank_doc_count}")
          print(f"  rerank_vocab_size={args.rerank_vocab_size}")
          print(f"  rerank_sentence_words=[{args.rerank_sentence_min_words},{args.rerank_sentence_max_words}]")
          print(f"  rerank_query={args.rerank_query}")
          print(f"  rerank_seed={args.rerank_seed}")

  
      results: List[Dict[str, Any]] = []

      total_jobs = len(run_names) * len(concurrency_values)
      job_idx = 0
      for name in run_names:

          scenario = scenarios[name]

          for c in concurrency_values:
              job_idx += 1
              print(f"\\n[{job_idx}/{total_jobs}] running {name} @ concurrency={c} ...")
              result = await run_single_scenario(
                  scenario=scenario,
                  duration_sec=args.duration,
                  concurrency=c,
                  max_requests=args.max_requests,
                  max_errors=args.max_errors,

                  rerank_dynamic_cfg=rerank_dynamic_cfg if name == "rerank" else None,

              )
              result["concurrency"] = c
              print(format_summary(result))
              results.append(result)
  
              if args.pause > 0 and job_idx < total_jobs:
                  await asyncio.sleep(args.pause)

  
      final = {
          "timestamp": time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()),
          "config": {
              "scenario": args.scenario,

              "run_names": run_names,

              "tenant_id": args.tenant_id,
              "duration_sec": args.duration,
              "concurrency": args.concurrency,

              "concurrency_list": concurrency_values,

              "max_requests": args.max_requests,
              "timeout_sec": args.timeout,
              "max_errors": args.max_errors,
              "backend_base": args.backend_base,
              "embedding_base": args.embedding_base,
              "translator_base": args.translator_base,
              "reranker_base": args.reranker_base,
              "cases_file": args.cases_file or None,

              "rerank_dynamic_docs": args.rerank_dynamic_docs,
              "rerank_doc_count": args.rerank_doc_count,
              "rerank_vocab_size": args.rerank_vocab_size,
              "rerank_sentence_min_words": args.rerank_sentence_min_words,
              "rerank_sentence_max_words": args.rerank_sentence_max_words,
              "rerank_query": args.rerank_query,
              "rerank_seed": args.rerank_seed,

          },
          "results": results,
          "overall": aggregate_results(results),
      }
  
      print("\\n=== Overall ===")
      print(json.dumps(final["overall"], ensure_ascii=False, indent=2))
  
      if args.output:
          out_path = Path(args.output)
          out_path.parent.mkdir(parents=True, exist_ok=True)
          out_path.write_text(json.dumps(final, ensure_ascii=False, indent=2), encoding="utf-8")
          print(f"Saved JSON report: {out_path}")
  
      return 0
  
  
  def main() -> int:
      try:
          return asyncio.run(main_async())
      except KeyboardInterrupt:
          print("Interrupted by user")
          return 130
  
  
  if __name__ == "__main__":
      raise SystemExit(main())