"""Hide VideoHelperSuite's background command windows without changing its media commands."""
import ast
import pathlib
import shutil
import sys

def patch(source):
    lines = source.splitlines(keepends=True)
    offsets = [0]
    for line in lines:
        offsets.append(offsets[-1] + len(line.encode('utf-8')))
    raw = source.encode('utf-8')
    calls = []
    for node in ast.walk(ast.parse(source)):
        if not isinstance(node, ast.Call) or not isinstance(node.func, ast.Attribute):
            continue
        if not isinstance(node.func.value, ast.Name) or node.func.value.id != 'subprocess' or node.func.attr not in ('Popen', 'run', 'check_output', 'check_call', 'call'):
            continue
        if any(k.arg == 'creationflags' for k in node.keywords):
            continue
        calls.append(node)
    for node in sorted(calls, key=lambda n: (n.end_lineno, n.end_col_offset), reverse=True):
        end = offsets[node.end_lineno - 1] + node.end_col_offset - 1
        prefix = b'' if raw[:end].rstrip().endswith(b',') else b','
        raw = raw[:end] + prefix + b" creationflags=getattr(subprocess, 'CREATE_NO_WINDOW', 0)" + raw[end:]
    result = raw.decode('utf-8')
    ast.parse(result)
    return result

if __name__ == '__main__':
    root = pathlib.Path(sys.argv[1]).resolve(strict=True)
    plans = []
    for name in ('nodes.py', 'utils.py', 'load_video_nodes.py'):
        path = root / 'videohelpersuite' / name
        source = path.read_text(encoding='utf-8')
        plans.append((path, source, patch(source)))
    for path, source, result in plans:
        if source == result:
            print(f'Already patched: {path.name}')
            continue
        backup = path.with_suffix('.py.before-aigen-hidden')
        if backup.exists():
            raise RuntimeError(f'Backup already exists: {backup}')
        shutil.copy2(path, backup)
        path.write_text(result, encoding='utf-8')
        print(f'Patched {path.name}; original backed up.')