from __future__ import annotations

import runpy
from collections.abc import Callable
from pathlib import Path
from typing import cast

import pytest

PATCH_SCRIPT = Path(__file__).parents[1] / "runtime" / "native-sandbox" / "patch_merged_usr.py"


def test_patch_skips_only_symlink_aliases_covered_by_read_allow(tmp_path: Path):
    namespace = runpy.run_path(str(PATCH_SCRIPT))
    patch_file = cast(Callable[[Path], None], namespace["patch_file"])

    source = tmp_path / "linux-sandbox-utils.js"
    source.write_text(
        """function pushReadDenyDirMounts(args, normalizedPath, allowedWritePaths, readAllowPaths) {
    const denySep = normalizedPath === '/' ? '/' : normalizedPath + '/';
    args.push('--tmpfs', normalizedPath);
    for (const writePath of allowedWritePaths) {
        if (writePath.startsWith(denySep) || writePath === normalizedPath) {
            args.push('--bind', writePath, writePath);
        }
    }
    for (const allowPath of readAllowPaths) {
        if (allowPath.startsWith(denySep) || allowPath === normalizedPath) {
            if (!fs.existsSync(allowPath)) {
                continue;
            }
            if (allowedWritePaths.some(w => (w.startsWith(denySep) || w === normalizedPath) &&
                (allowPath === w || allowPath.startsWith(w + '/')))) {
                continue;
            }
            args.push('--ro-bind', allowPath, allowPath);
            logForDebugging(`[Sandbox Linux] Re-allowed read access within denied region: ${allowPath}`);
        }
    }
}
    const rootSkip = new Set(['proc', 'dev', 'sys']);
    for (const p of readConfig?.denyOnly || []) {
        if (normalizePathForSandbox(p) === '/') {
            for (const child of fs.readdirSync('/')) {
                if (!rootSkip.has(child))
                    readDenyPaths.push('/' + child);
            }
        }
""",
        encoding="utf-8",
    )

    patch_file(source)
    patched = source.read_text(encoding="utf-8")

    assert "isSymbolicLink()" in patched
    assert "readAllowPaths.some" in patched
    assert "resolved.startsWith(allowPath + '/')" in patched
    assert "args.push('--remount-ro', normalizedPath)" in patched
    assert "!allowedWritePaths.includes(normalizedPath)" in patched
    with pytest.raises(RuntimeError, match="already patched"):
        patch_file(source)