from __future__ import absolute_import

import array
import errno
import fcntl
import os
import sys

from . import encoding, pycompat, util


# BSD 'more' escapes ANSI color sequences by default. This can be disabled by
# $MORE variable, but there's no compatible option with Linux 'more'. Given
# OS X is widely used and most modern Unix systems would have 'less', setting
# 'less' as the default seems reasonable.
fallbackpager = "less"


def _rcfiles(path):
    rcs = [os.path.join(path, "hgrc")]
    rcdir = os.path.join(path, "hgrc.d")
    try:
        rcs.extend(
            [
                os.path.join(rcdir, f)
                for f, kind in util.listdir(rcdir)
                if f.endswith(".rc")
            ]
        )
    except OSError:
        pass
    return rcs


def systemrcpath():
    path = []
    if pycompat.sysplatform == "plan9":
        root = "lib/mercurial"
    else:
        root = "etc/mercurial"
    # old mod_python does not set sys.argv
    if len(getattr(sys, "argv", [])) > 0:
        p = os.path.dirname(os.path.dirname(pycompat.sysargv[0]))
        if p != "/":
            path.extend(_rcfiles(os.path.join(p, root)))
    path.extend(_rcfiles("/" + root))
    return path


def userrcpath():
    if pycompat.sysplatform == "plan9":
        return [encoding.environ["home"] + "/lib/hgrc"]
    elif pycompat.isdarwin:
        return [os.path.expanduser("~/.hgrc")]
    else:
        confighome = encoding.environ.get("XDG_CONFIG_HOME")
        if confighome is None or not os.path.isabs(confighome):
            confighome = os.path.expanduser("~/.config")

        return [os.path.expanduser("~/.hgrc"), os.path.join(confighome, "hg", "hgrc")]


def termsize(ui):
    try:
        import termios

        TIOCGWINSZ = termios.TIOCGWINSZ  # unavailable on IRIX (issue3449)
    except (AttributeError, ImportError):
        return 80, 24

    for dev in (ui.ferr, ui.fout, ui.fin):
        try:
            try:
                fd = dev.fileno()
            except AttributeError:
                continue
            if not os.isatty(fd):
                continue
            arri = fcntl.ioctl(fd, TIOCGWINSZ, "\0" * 8)
            height, width = array.array(r"h", arri)[:2]
            if width > 0 and height > 0:
                return width, height
        except ValueError:
            pass
        except IOError as e:
            if e[0] == errno.EINVAL:
                pass
            else:
                raise
    return 80, 24