import io
import sys
from pathlib import Path

import pytest

sys.path.insert(0, str(Path(__file__).resolve().parent.parent / "tools"))

import rsync_progress  # noqa: E402


class NotATerminal(io.StringIO):
    def isatty(self):
        return False


class Terminal(io.StringIO):
    def isatty(self):
        return True


def run(lines, total=0, out=None):
    out = out or NotATerminal()
    rsync_progress.main(["--total", str(total)], stream=io.StringIO(lines), out=out)
    return out.getvalue()


def test_the_artist_and_album_are_pulled_from_the_path():
    assert rsync_progress.album_of("Pendulum/Immersion/01 - Watercolour.mp3") == (
        "Pendulum / Immersion"
    )


def test_a_shallower_path_degrades_rather_than_failing():
    assert rsync_progress.album_of("Pendulum/loose.mp3") == "Pendulum"
    assert rsync_progress.album_of("loose.mp3") == ""


def test_directories_are_not_counted():
    """rsync reports them too, and counting them puts the percentage past 100."""
    output = run("Artist/\nArtist/Album/\nArtist/Album/track.mp3\n", total=1)

    assert "1 / 1" in output
    assert "100%" in output


def test_the_percentage_tracks_the_total():
    output = run("".join(f"A/B/{i}.mp3\n" for i in range(5)), total=10)

    assert "5 / 10" in output
    assert " 50%" in output


def test_without_a_total_it_counts_instead_of_guessing():
    output = run("A/B/one.mp3\nA/B/two.mp3\n")

    assert "2 files" in output
    assert "%" not in output


def test_a_final_line_is_always_printed():
    """Otherwise the last state of a rewriting line is whatever it happened to
    be when the interval last elapsed."""
    output = run("A/B/one.mp3\n", total=1)

    assert output.endswith("\n")
    assert "1 / 1" in output


def test_nothing_transferred_still_reports():
    output = run("", total=0)

    assert "0 files" in output


def test_a_log_gets_no_carriage_returns():
    """A non-terminal filling with \\r and escape codes is unreadable."""
    output = run("".join(f"A/B/{i}.mp3\n" for i in range(50)), total=50)

    assert "\r" not in output
    assert "\033" not in output


def test_a_terminal_rewrites_one_line():
    output = run("".join(f"A/B/{i}.mp3\n" for i in range(50)), total=50, out=Terminal())

    assert "\r\033[2K" in output


@pytest.mark.parametrize(
    ("text", "width", "expected"),
    [
        ("short", 20, "short"),
        ("King Gizzard / PetroDragonic Apocalypse", 20, "…agonic Apocalypse"),
    ],
)
def test_long_labels_are_trimmed_from_the_left(text, width, expected):
    """The album is the informative end, so the artist is what gets cut."""
    trimmed = rsync_progress.fit(text, width)

    assert len(trimmed) <= width
    if len(text) > width:
        assert trimmed.startswith("…")
        assert text.endswith(trimmed.lstrip("…"))