"""CLI 入口（`dwg_review.__main__`）参数解析与来源判定单测。

只测**纯逻辑**（不真连 CAD、不真调 LLM）：位置参数 → (source, source_path) 的判定，
以及 CAD-only 选项在离线源下被拒绝。
"""

from PIL import Image

from dwg_review.__main__ import _resolve_source_arg, build_parser


def test_parser_accepts_positional_source():
    args = build_parser().parse_args(["a.pdf"])
    assert args.source == "a.pdf"


def test_parser_source_optional():
    assert build_parser().parse_args([]).source is None


def test_parser_keeps_existing_flags():
    args = build_parser().parse_args(["a.pdf", "--plan-only", "--frames", "3"])
    assert args.plan_only is True and args.frames == 3


def test_resolve_no_source_is_cad_mode():
    assert _resolve_source_arg(None) == (None, None)


def test_resolve_pdf(tmp_path):
    path = tmp_path / "d.pdf"
    path.write_bytes(b"%PDF-1.4\n")
    resolved, err = _resolve_source_arg(str(path))
    assert err is None
    assert resolved[0] == "pdf"
    assert resolved[1].endswith("d.pdf")


def test_resolve_image(tmp_path):
    path = tmp_path / "d.png"
    Image.new("RGB", (10, 10)).save(path)
    resolved, err = _resolve_source_arg(str(path))
    assert err is None and resolved[0] == "image"


def test_resolve_dwg_falls_back_to_cad_mode(capsys):
    """DWG 参数无法在 Python 侧打开 → 提示后按 CAD 在线模式运行（source=None）。"""
    resolved, err = _resolve_source_arg("x.dwg")
    assert resolved is None and err is None
    assert "CAD 在线模式" in capsys.readouterr().out


def test_resolve_missing_file_errors(tmp_path):
    resolved, err = _resolve_source_arg(str(tmp_path / "nope.pdf"))
    assert resolved is None and "文件不存在" in err


def test_resolve_unknown_extension_errors():
    resolved, err = _resolve_source_arg("x.svg")
    assert resolved is None and "无法识别" in err