#!/usr/bin/env python3
"""Validate real HTTP parsing and generation at allocated KV boundaries."""
import argparse
import json
import urllib.error
import urllib.request

p = argparse.ArgumentParser(description=__doc__)
p.add_argument("--url", default="http://127.0.0.1:19095")
a = p.parse_args()
client = urllib.request.build_opener(urllib.request.ProxyHandler({}))

def call(path, body=None, padding=0):
    payload = None if body is None else json.dumps(body).encode() + b" " * padding
    req = urllib.request.Request(a.url + path, payload, {"Content-Type": "application/json"})
    with client.open(req, timeout=600) as response:
        return json.load(response)

def request(text, **extra):
    return {"model": "mindnano-ling3-tiny", "temperature": 0,
            "messages": [{"role": "user", "content": text}], **extra}

capacity = call("/health")["context_length"]
results = {}
for budget in (4096, 2**64 - 1):
    r = call("/v1/chat/completions", request("1" * 107, max_tokens=budget, stop="1"))
    assert r["choices"][0]["finish_reason"] == "stop", r
    assert r["mindnano_metrics"]["effective_max_tokens"] == min(budget, capacity - 128)
    results[str(budget)] = r["mindnano_metrics"]

r = call("/v1/chat/completions", request("你好", max_tokens=1), padding=1024*1024+1)
assert r["usage"]["completion_tokens"] == 1
results["body_over_1mib"] = r["mindnano_metrics"]

# Repeated digit input has one token per character; the chat template adds 21.
# No requested max: verify actual output crosses the previous default of 128.
prompt_length = capacity - 160
r = call("/v1/chat/completions", request("1" * (prompt_length - 21)))
assert r["usage"] == {"prompt_tokens": prompt_length, "completion_tokens": 160,
                       "total_tokens": capacity, "prompt_tokens_details": {"cached_tokens": r["mindnano_metrics"]["cached_tokens"]}}, r
assert r["choices"][0]["finish_reason"] == "length"
assert r["mindnano_metrics"]["context_capacity_reached"]
results["default_over_128"] = r["mindnano_metrics"]

for remaining in (1, 0):
    r = call("/v1/chat/completions", request("1" * (capacity - remaining - 21), max_tokens=2**64-1))
    assert r["usage"]["prompt_tokens"] == capacity - remaining
    assert r["usage"]["completion_tokens"] == remaining, r
    assert r["choices"][0]["finish_reason"] == "length"
    assert r["mindnano_metrics"]["context_capacity_reached"]
    if remaining == 0:
        assert r["choices"][0]["message"]["content"] == ""
        assert r["mindnano_metrics"]["ttft_ms"] is None
    results[f"remaining_{remaining}"] = r["mindnano_metrics"]

try:
    call("/v1/chat/completions", request("1" * (capacity + 1 - 21), max_tokens=1))
    raise AssertionError("oversized input accepted")
except urllib.error.HTTPError as e:
    assert e.code == 400 and json.load(e)["error"]["code"] == "context_length_exceeded"
assert not call("/health")["active"]
print(json.dumps({"passed": True, "capacity": capacity, "cases": results}, indent=2))