import os
import pty
import select

import pytest

from tamq.terminal import (
    TerminalOutputError,
    format_comment,
    format_pushy_input,
    terminal_frame,
    write_terminal_output,
)


def test_comment_format_escapes_controls_and_prefixes_every_line():
    assert format_comment("repo-a", "first\nsecond\x1b[31m", "m-1") == (
        "#repo-a: first\n# second\\x1b[31m [m-1]"
    )


def test_pushy_input_is_one_sanitized_shell_comment():
    assert format_pushy_input("repo-a", "first\nsecond\x1b[31m", "m-1") == (
        "# from repo-a: first\\x0asecond\\x1b[31m [m-1]"
    )


def test_terminal_frame_scrolls_only_rows_above_the_cursor():
    assert terminal_frame(
        "repo-a", "first\nsecond", "m-1", cursor_y=8, pane_height=24
    ) == (
        "\x1b7\x1b[1;8r\x1b[8;1H"
        "\n\r#repo-a: first\n\r# second [m-1]"
        "\x1b[r\x1b8"
    )


def test_terminal_frame_falls_back_when_stable_region_is_not_safe():
    expected = "\r\n#repo-a: hello [m-1]\r\n"
    assert terminal_frame("repo-a", "hello", "m-1", cursor_y=0, pane_height=24) == expected
    assert terminal_frame(
        "repo-a", "hello", "m-1", cursor_y=8, pane_height=24, alternate_on=True
    ) == expected
    assert terminal_frame("repo-a", "hello", "m-1") == (
        "\r\n#repo-a: hello [m-1]\r\n"
    )


def test_terminal_output_reaches_pty_output_but_not_input():
    master, slave = pty.openpty()
    try:
        tty_path = os.ttyname(slave)
        write_terminal_output(tty_path, terminal_frame("repo-a", "hello", "m-1"))

        readable, _, _ = select.select([master], [], [], 1)
        assert readable == [master]
        assert b"#repo-a: hello [m-1]" in os.read(master, 4096)
        readable_input, _, _ = select.select([slave], [], [], 0)
        assert readable_input == []
    finally:
        os.close(master)
        os.close(slave)


def test_terminal_output_rejects_non_pty_paths(tmp_path):
    target = tmp_path / "ordinary-file"
    target.write_text("untouched", encoding="utf-8")
    with pytest.raises(TerminalOutputError, match="non-PTY"):
        write_terminal_output(target, "message")
    assert target.read_text(encoding="utf-8") == "untouched"