import os
from pathlib import Path

from knoe.core.build_context import copy_build_context_dir


def test_copy_build_context_dir_ignores_data_and_keeps_dangling_symlinks(tmp_path: Path):
    source_dir = tmp_path / "source"
    build_dir = tmp_path / "build"
    source_dir.mkdir()

    (source_dir / "Dockerfile").write_text("FROM scratch\n")
    (source_dir / "keep.txt").write_text("ok")

    # Create a runtime-like `data/` tree that may contain problematic entries.
    pgdata = source_dir / "data" / "pvc-123" / "pgdata"
    pgdata.mkdir(parents=True)
    if hasattr(os, "symlink"):
        os.symlink("does_not_exist", pgdata / "pg_wal")

    # Also ensure we can copy dangling symlinks outside ignored directories.
    if hasattr(os, "symlink"):
        os.symlink("missing_target", source_dir / "dangling_link")

    # Pre-create build_dir with stale content to ensure it gets replaced.
    build_dir.mkdir()
    (build_dir / "stale.txt").write_text("stale")

    copy_build_context_dir(source_dir, build_dir)

    assert (build_dir / "Dockerfile").exists()
    assert (build_dir / "keep.txt").read_text() == "ok"
    assert not (build_dir / "stale.txt").exists()

    # `data/` should never be part of the Docker build context.
    assert not (build_dir / "data").exists()

    if hasattr(os, "symlink"):
        link = build_dir / "dangling_link"
        assert link.is_symlink()
        assert os.readlink(link) == "missing_target"