"""build_ydl_opts: the mp4 compat profile must SELECT H.264 (not merely prefer it), so shared
downloads play on iOS/Safari, while custom vcodec / non-mp4 profiles opt out. See the iPad AV1
broken-player fix."""
from app.downloads import edit as editmod
from app.downloads import formats


def _opts(spec):
    return formats.build_ydl_opts(spec, "/tmp/%(id)s.%(ext)s", lambda d: None)


def test_mp4_default_selects_avc1_with_progressive_fallback():
    fmt = _opts({"mode": "av", "container": "mp4"})["format"]
    # avc1 video-only first, then the avc1 progressive, then an unrestricted fallback.
    assert fmt.startswith("bestvideo[vcodec^=avc1]+bestaudio[acodec^=mp4a]")
    assert "/best[vcodec^=avc1]" in fmt
    assert fmt.endswith("bestvideo+bestaudio/best")


def test_format_sig_salt_forks_a_distinct_identity():
    spec = {"mode": "av", "container": "mp4", "max_height": 720}
    base = formats.format_sig(spec)
    # A salt yields a distinct cache identity (force-redownload's private-asset fork); different
    # salts differ from each other and from the unsalted sig, same salt is stable.
    assert formats.format_sig(spec, salt="7:12") != base
    assert formats.format_sig(spec, salt="7:12") != formats.format_sig(spec, salt="7:13")
    assert formats.format_sig(spec, salt="7:12") == formats.format_sig(spec, salt="7:12")


def test_mp4_default_keeps_h264_sort_tiebreaker():
    sort = _opts({"mode": "av", "container": "mp4"})["format_sort"]
    assert "vcodec:h264" in sort and "acodec:aac" in sort


def test_video_only_mp4_selects_avc1():
    fmt = _opts({"mode": "v", "container": "mp4"})["format"]
    assert fmt.startswith("bestvideo[vcodec^=avc1]")
    assert "+bestaudio" not in fmt  # video-only never merges audio
    # A video-only download stays audio-free: every `bestvideo` (video-only) option is preferred
    # over any `best` (progressive, audio-bearing) fallback.
    assert fmt.index("bestvideo") < fmt.index("best[vcodec^=avc1]") < fmt.rindex("/best")


def test_max_height_caps_every_branch():
    fmt = _opts({"mode": "av", "container": "mp4", "max_height": 720})["format"]
    assert fmt.count("[height<=?720]") >= 3  # applied to each avc1/fallback branch


def test_explicit_vcodec_opts_out_of_avc1_selector():
    opts = _opts({"mode": "av", "container": "mp4", "vcodec": "vp9"})
    assert "vcodec^=avc1" not in opts["format"]
    assert opts["format"] == "bestvideo+bestaudio/best"
    assert "vcodec:vp9" in opts["format_sort"]


def test_non_mp4_container_opts_out():
    fmt = _opts({"mode": "av", "container": "webm"})["format"]
    assert "vcodec^=avc1" not in fmt


def test_audio_only_unaffected():
    assert _opts({"mode": "a", "audio_format": "m4a"})["format"] == "bestaudio/best"


def test_browser_transcode_flags_universal_playability():
    F = editmod.browser_transcode_flags
    # Already universal: H.264 + AAC in mp4 → no change.
    assert F("h264", "aac", True) == (False, False, False)
    assert F("h264", "mp3", True) == (False, False, False)
    # Non-H.264 video → full video re-encode (AV1/VP9 fail iOS; HEVC fails Chrome/FF).
    assert F("av1", "aac", True) == (True, True, False)
    assert F("vp9", "opus", True) == (True, True, True)
    assert F("hevc", "aac", True) == (True, True, False)
    # H.264 but bad audio → audio-only transcode (video copied).
    assert F("h264", "opus", True) == (True, False, True)
    # Codecs fine but wrong container → remux only (no re-encode).
    assert F("h264", "aac", False) == (True, False, False)
    # A failed probe / missing stream is never re-encoded.
    assert F(None, None, True) == (False, False, False)