"""Persist compact per-step sampler state for one direct FL2VA parity run."""

from pathlib import Path


path = Path("/opt/ComfyUI/comfy/samplers.py")
source = path.read_text(encoding="utf-8")
if "import os\n" not in source:
    source = source.replace("import logging\n", "import logging\nimport os\n")

old = "            if callback is not None:\n                callback(x[\"i\"], x[\"denoised\"], x[\"x\"], total_steps)\n"
new = (
    "            capture_dir = os.getenv(\"H3_SAMPLER_CAPTURE_DIR\")\n"
    "            if capture_dir:\n"
    "                os.makedirs(capture_dir, exist_ok=True)\n"
    "                if x[\"i\"] == 0:\n"
    "                    torch.save({\"sigmas\": sigmas.detach().cpu(), \"initial_x\": x[\"x\"].detach().cpu()}, os.path.join(capture_dir, \"initial.pt\"))\n"
    "                torch.save({\"sigma\": x[\"sigma\"].detach().cpu(), \"denoised\": x[\"denoised\"].detach().cpu(), \"x\": x[\"x\"].detach().cpu()}, os.path.join(capture_dir, f\"step_{x[\"i\"]:02d}.pt\"))\n"
    "            if callback is not None:\n"
    "                callback(x[\"i\"], x[\"denoised\"], x[\"x\"], total_steps)\n"
)
if source.count(old) == 1:
    source = source.replace(old, new)
elif new not in source:
    raise RuntimeError("Unable to locate Comfy sampler callback.")
path.write_text(source, encoding="utf-8")
print("Applied H3 sampler reference capture patch.")