#!/usr/bin/env python3
"""Run a private, deterministic llama.cpp vision latency smoke test."""

from __future__ import annotations

import argparse
import base64
import json
import struct
import time
import urllib.request
import zlib


def chunk(kind: bytes, payload: bytes) -> bytes:
    return (
        struct.pack(">I", len(payload))
        + kind
        + payload
        + struct.pack(">I", zlib.crc32(kind + payload) & 0xFFFFFFFF)
    )


def synthetic_png(width: int = 1024, height: int = 768) -> bytes:
    rows = []
    for y in range(height):
        row = bytearray([0])
        for x in range(width):
            row.extend(((x * 255) // width, (y * 255) // height, ((x // 64 + y // 64) % 2) * 210))
        rows.append(bytes(row))
    payload = zlib.compress(b"".join(rows), level=6)
    return (
        b"\x89PNG\r\n\x1a\n"
        + chunk(b"IHDR", struct.pack(">IIBBBBB", width, height, 8, 2, 0, 0, 0))
        + chunk(b"IDAT", payload)
        + chunk(b"IEND", b"")
    )


def main() -> None:
    parser = argparse.ArgumentParser()
    parser.add_argument("--url", required=True)
    parser.add_argument("--model", default="qwen-medium")
    args = parser.parse_args()

    image = base64.b64encode(synthetic_png()).decode("ascii")
    body = {
        "model": args.model,
        "messages": [
            {
                "role": "user",
                "content": [
                    {
                        "type": "image_url",
                        "image_url": {"url": f"data:image/png;base64,{image}"},
                    },
                    {
                        "type": "text",
                        "text": "Beschreibe dieses synthetische Testbild knapp auf Deutsch.",
                    },
                ],
            }
        ],
        "temperature": 0,
        "max_tokens": 500,
        "reasoning_effort": "none",
        "cache_prompt": False,
    }
    request = urllib.request.Request(
        args.url.rstrip("/") + "/v1/chat/completions",
        data=json.dumps(body).encode("utf-8"),
        headers={"Content-Type": "application/json"},
    )
    started = time.perf_counter()
    with urllib.request.urlopen(request, timeout=600) as response:
        result = json.load(response)
    elapsed = time.perf_counter() - started
    print(
        json.dumps(
            {
                "wall_seconds": round(elapsed, 3),
                "usage": result.get("usage"),
                "timings": result.get("timings"),
                "answer": result["choices"][0]["message"].get("content", "")[:240],
            },
            ensure_ascii=False,
            indent=2,
        )
    )


if __name__ == "__main__":
    main()