import struct
import zlib

import httpx
import pytest

from app.config import Settings
from app.main import create_app

COMFY = "http://comfy.test"
FAKE_KEY = "sk-test-1234"


def settings(**overrides) -> Settings:
    base = dict(
        comfy_base_url=COMFY,
        adapter_api_key=FAKE_KEY,
        validate_templates_on_server=False,
        poll_interval=0.0,
        execution_timeout=5.0,
    )
    base.update(overrides)
    return Settings(**base)


def png_bytes(w: int = 64, h: int = 64) -> bytes:
    def chunk(t: bytes, d: bytes) -> bytes:
        return struct.pack(">I", len(d)) + t + d + struct.pack(">I", zlib.crc32(t + d))

    ihdr = struct.pack(">IIBBBBB", w, h, 8, 2, 0, 0, 0)
    iend = b"\x89PNG\r\n\x1a\n" + chunk(b"IHDR", ihdr) + chunk(b"IDAT", zlib.compress(b"\x00" * (w * 3 + 1) * h)) + chunk(b"IEND", b"")
    return iend


def png_size(data: bytes) -> tuple[int, int]:
    return struct.unpack(">II", data[16:24])


@pytest.fixture
async def client():
    """Async client bound to the app with lifespan running
    (templates loaded, comfy client targeting http://comfy.test)."""
    import contextlib

    app = create_app(settings())
    async with contextlib.AsyncExitStack() as stack:
        await stack.enter_async_context(app.router.lifespan_context(app))
        transport = httpx.ASGITransport(app=app)
        async with httpx.AsyncClient(transport=transport, base_url="http://adapter.test") as ac:
            ac.headers["Authorization"] = f"Bearer {FAKE_KEY}"
            yield ac