"""Render an isolated four-file scene while denying reads of original sources.

Uses temporary hardlinks (or copies across devices) under replay. Never changes
source files. Python audit hooks reject reads from the original dataset and old
transition directory, including backups. This is a runtime dependency test, not
a clean-machine installation or sandbox/security guarantee.
"""
import argparse
import json
import os
from pathlib import Path
import shutil
import sys
import tempfile


def main():
    p = argparse.ArgumentParser(description=__doc__)
    p.add_argument('--scene', type=Path, required=True)
    p.add_argument('--output-dir', type=Path, required=True)
    p.add_argument('--device', default='cuda:2')
    p.add_argument('--deny-root', type=Path, action='append', default=[])
    args = p.parse_args()
    original = args.scene.resolve()
    c = json.loads((original / 'render/scene.json').read_text())
    args.output_dir.mkdir(parents=True, exist_ok=True)
    blocked = [original.parent, *[p.resolve() for p in args.deny_root]]
    with tempfile.TemporaryDirectory(prefix='isolated_scene_', dir=args.output_dir) as tmp:
        isolated = Path(tmp)
        inputs = ['render/scene.json', *[c[k] for k in ('foreground', 'background', 'target_image')]]
        for name in inputs:
            src = (original / name).resolve()
            assert src.is_relative_to(original)
            dst = isolated / name
            dst.parent.mkdir(parents=True, exist_ok=True)
            try:
                os.link(src, dst)
            except OSError:
                shutil.copy2(src, dst)

        def reject_sources(event, values):
            if event != 'open' or not isinstance(values[0], (str, bytes, os.PathLike)):
                return
            try:
                path = Path(os.fsdecode(values[0])).resolve()
            except (OSError, ValueError):
                return
            if any(path.is_relative_to(root) for root in blocked):
                raise PermissionError(f'Portability test prohibited source read: {path}')
        sys.addaudithook(reject_sources)
        # Install guard before importing renderer and its dependency graph.
        from render_scene import render
        from package_trajectories import write_json
        result = render(isolated, args.output_dir / 'render', args.device, width=320, use_cache=False)
        result.update(status='passed', isolated_inputs=inputs, denied_source_roots=list(map(str, blocked)),
                      input_count=len(inputs), original_assets_modified=False,
                      note='Python-level read audit plus minimal scene runtime test; external binary syscalls are not a security sandbox.')
        write_json(args.output_dir / 'portability.json', result)
        print(json.dumps(result), flush=True)


if __name__ == '__main__':
    main()