from pathlib import Path
ROOT=Path(__file__).resolve().parents[1]

def test_version():
    assert (ROOT/"VERSION").read_text(encoding="utf-8").strip()=="4.6.15"

def test_opfs_is_probed_not_assumed():
    js=(ROOT/"static"/"js"/"app.js").read_text(encoding="utf-8")
    assert "async function probeOpfsWritable" in js
    assert 'getFileHandle("__probe__.tmp"' in js
    assert "OPFS_CAPABILITY=false" in js

def test_opfs_failure_falls_back_without_counting_file_failed():
    js=(ROOT/"static"/"js"/"app.js").read_text(encoding="utf-8")
    assert "function isOpfsUnavailableError" in js
    assert "streamManagedDownloadFallback" in js
    assert "不会把兼容性问题记为文件失败" in js

def test_main_and_retry_paths_use_probe():
    js=(ROOT/"static"/"js"/"app.js").read_text(encoding="utf-8")
    assert js.count("if(await probeOpfsWritable())") >= 2

def test_real_transport_failure_is_explained():
    js=(ROOT/"static"/"js"/"app.js").read_text(encoding="utf-8")
    assert "当前文件在实际传输阶段重试后仍失败" in js