"""Helper utilities related to IO."""
import errno
import logging
import os
import subprocess as sp
from subprocess import PIPE, Popen
import sys
import termios
from textwrap import wrap
import tty
from typing import Callable, Iterator
from . import shell
from .meta import scriptname
logger = logging.getLogger(__name__)
[docs]def getch(prompt: str = None) -> str:
"""Reads a single character from stdin.
Args:
prompt: prompt that is presented to user.
Returns:
The single character that was read.
"""
if prompt:
sys.stdout.write(prompt)
sys.stdout.flush()
fd = sys.stdin.fileno()
old_settings = termios.tcgetattr(fd)
try:
tty.setraw(sys.stdin.fileno())
ch = sys.stdin.read(1)
finally:
termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
return ch
[docs]def ewrap(
multiline_msg: str, width: int = 80, indent: int = 0
) -> Iterator[str]:
"""A better version of textwrap.wrap()."""
for msg in multiline_msg.split("\n"):
if not msg:
yield ""
continue
msg = (" " * indent) + msg
i = 0
while i < len(msg) and msg[i] == " ":
i += 1
spaces = " " * i
for m in wrap(
msg, width, subsequent_indent=spaces, drop_whitespace=True
):
yield m
[docs]def efill(multiline_msg: str, width: int = 80, indent: int = 0) -> str:
"""A better version of textwrap.fill()."""
return "\n".join(ewrap(multiline_msg, width, indent))
[docs]def confirm(prompt: str) -> bool:
"""Prompt user for 'y' or 'n' answer.
Returns:
True iff the user responds to the @prompt with 'y'.
"""
prompt += " (y/n): "
y_or_n = input(prompt)
return y_or_n == "y"
[docs]def box(title: str) -> str:
"""Wraps @title in a pretty ASCII box."""
middle = f"| {title} |"
top = bottom = "+" + ("-" * (len(middle) - 2)) + "+"
return f"{top}\n{middle}\n{bottom}"
[docs]def create_dir(directory: str) -> None:
"""Create directory if it does not already exist.
Args:
directory: The full directory path.
"""
try:
os.makedirs(directory)
except OSError as e:
if e.errno != errno.EEXIST:
raise
[docs]def mkfifo(fifo_path: str) -> None:
"""Creates named pipe if it does not already exist.
Args:
fifo_path: The full file path where the named pipe will be created.
"""
try:
os.mkfifo(fifo_path)
except OSError:
pass
[docs]def copy_to_clipboard(clip: str) -> None:
"""Copys a clip to the system clipboard.
Args:
clip: The clip that gets copied into the clipboard.
"""
if shell.command_exists("xclip"):
tool = "xclip"
cmd_list = ["xclip", "-sel", "clip"]
elif shell.command_exists("pbcopy"):
tool = "pbcopy"
cmd_list = ["pbcopy"]
else:
logger.warning("Neither xclip nor pbcopy are installed.")
return
popen = Popen(cmd_list, stdin=PIPE)
popen.communicate(input=clip.encode())
logger.info("Copied %s into clipboard using %s.", clip, tool)
[docs]def notify(
*args: str, title: str = None, urgency: str = None, up: int = 0
) -> None:
"""
Sends desktop notification with calling script's name as the notification
title.
Args:
*args: Arguments to be passed to the notify-send command.
title: Notification title.
urgency: Notification urgency.
up: How far should we crawl up the stack to get the script's name?
"""
try:
assert args, "No notification message specified."
assert urgency in (
None,
"low",
"normal",
"critical",
), "Invalid Urgency: {}".format(urgency)
except AssertionError as e:
raise ValueError(str(e)) from e
if title is None:
title = scriptname(up=up + 1)
cmd_list = ["notify-send"]
cmd_list.extend([title])
if urgency is not None:
cmd_list.extend(["-u", urgency])
cmd_list.extend(args)
sp.check_call(cmd_list)
[docs]def xkey(key: str) -> None:
"""Wrapper for `xdotool key`"""
sp.check_call(["xdotool", "key", key])
[docs]def xtype(keys: str, *, delay: int = None) -> None:
"""Wrapper for `xdotool type`
Args:
keys (str): Keys to type.
delay (optional): Typing delay.
"""
if delay is None:
delay = 150
keys = keys.strip("\n")
sp.check_call(["xdotool", "type", "--delay", str(delay), keys])
def _color_factory(N: int) -> Callable[[str], str]:
def color(msg: str) -> str:
return "%s%s%s" % ("\033[{}m".format(N), msg, "\033[0m")
return color
[docs]class colors:
"""Namespace for <color>() functions."""
black = _color_factory(30)
blue = _color_factory(34)
cyan = _color_factory(36)
green = _color_factory(32)
magenta = _color_factory(35)
red = _color_factory(31)
white = _color_factory(37)
yellow = _color_factory(33)