# Copyright 2013-2019 Lawrence Livermore National Security, LLC and other
# Spack Project Developers. See the top-level COPYRIGHT file for details.
#
# SPDX-License-Identifier: (Apache-2.0 OR MIT)

from datetime import datetime
import fcntl
import os
import struct
import sys
import termios
import textwrap
import traceback
from six import StringIO
from six.moves import input

from llnl.util.tty.color import cprint, cwrite, cescape, clen

_debug = False
_verbose = False
_stacktrace = False
_timestamp = False
_msg_enabled = True
_warn_enabled = True
_error_enabled = True
indent = "  "


def is_verbose():
    return _verbose


def is_debug():
    return _debug


def is_stacktrace():
    return _stacktrace


def set_debug(flag):
    global _debug
    _debug = flag


def set_verbose(flag):
    global _verbose
    _verbose = flag


def set_timestamp(flag):
    global _timestamp
    _timestamp = flag


def set_msg_enabled(flag):
    global _msg_enabled
    _msg_enabled = flag


def set_warn_enabled(flag):
    global _warn_enabled
    _warn_enabled = flag


def set_error_enabled(flag):
    global _error_enabled
    _error_enabled = flag


def msg_enabled():
    return _msg_enabled


def warn_enabled():
    return _warn_enabled


def error_enabled():
    return _error_enabled


class SuppressOutput:
    """Class for disabling output in a scope using 'with' keyword"""

    def __init__(self,
                 msg_enabled=True,
                 warn_enabled=True,
                 error_enabled=True):

        self._msg_enabled_initial = _msg_enabled
        self._warn_enabled_initial = _warn_enabled
        self._error_enabled_initial = _error_enabled

        self._msg_enabled = msg_enabled
        self._warn_enabled = warn_enabled
        self._error_enabled = error_enabled

    def __enter__(self):
        set_msg_enabled(self._msg_enabled)
        set_warn_enabled(self._warn_enabled)
        set_error_enabled(self._error_enabled)

    def __exit__(self, exc_type, exc_val, exc_tb):
        set_msg_enabled(self._msg_enabled_initial)
        set_warn_enabled(self._warn_enabled_initial)
        set_error_enabled(self._error_enabled_initial)


def set_stacktrace(flag):
    global _stacktrace
    _stacktrace = flag


def process_stacktrace(countback):
    """Gives file and line frame 'countback' frames from the bottom"""
    st = traceback.extract_stack()
    # Not all entries may be spack files, we have to remove those that aren't.
    file_list = []
    for frame in st:
        # Check that the file is a spack file
        if frame[0].find("/spack") >= 0:
            file_list.append(frame[0])
    # We use commonprefix to find what the spack 'root' directory is.
    root_dir = os.path.commonprefix(file_list)
    root_len = len(root_dir)
    st_idx = len(st) - countback - 1
    st_text = "%s:%i " % (st[st_idx][0][root_len:], st[st_idx][1])
    return st_text


def get_timestamp(force=False):
    """Get a string timestamp"""
    if _debug or _timestamp or force:
        return datetime.now().strftime("[%Y-%m-%d-%H:%M:%S.%f] ")
    else:
        return ''


def msg(message, *args, **kwargs):
    if not msg_enabled():
        return

    newline = kwargs.get('newline', True)
    st_text = ""
    if _stacktrace:
        st_text = process_stacktrace(2)
    if newline:
        cprint("@*b{%s==>} %s%s" % (
            st_text, get_timestamp(), cescape(message)))
    else:
        cwrite("@*b{%s==>} %s%s" % (
            st_text, get_timestamp(), cescape(message)))
    for arg in args:
        print(indent + str(arg))


def info(message, *args, **kwargs):
    format = kwargs.get('format', '*b')
    stream = kwargs.get('stream', sys.stdout)
    wrap = kwargs.get('wrap', False)
    break_long_words = kwargs.get('break_long_words', False)
    st_countback = kwargs.get('countback', 3)

    st_text = ""
    if _stacktrace:
        st_text = process_stacktrace(st_countback)
    cprint("@%s{%s==>} %s%s" % (
        format, st_text, get_timestamp(), cescape(str(message))),
        stream=stream)
    for arg in args:
        if wrap:
            lines = textwrap.wrap(
                str(arg), initial_indent=indent, subsequent_indent=indent,
                break_long_words=break_long_words)
            for line in lines:
                stream.write(line + '\n')
        else:
            stream.write(indent + str(arg) + '\n')


def verbose(message, *args, **kwargs):
    if _verbose:
        kwargs.setdefault('format', 'c')
        info(message, *args, **kwargs)


def debug(message, *args, **kwargs):
    if _debug:
        kwargs.setdefault('format', 'g')
        kwargs.setdefault('stream', sys.stderr)
        info(message, *args, **kwargs)


def error(message, *args, **kwargs):
    if not error_enabled():
        return

    kwargs.setdefault('format', '*r')
    kwargs.setdefault('stream', sys.stderr)
    info("Error: " + str(message), *args, **kwargs)


def warn(message, *args, **kwargs):
    if not warn_enabled():
        return

    kwargs.setdefault('format', '*Y')
    kwargs.setdefault('stream', sys.stderr)
    info("Warning: " + str(message), *args, **kwargs)


def die(message, *args, **kwargs):
    kwargs.setdefault('countback', 4)
    error(message, *args, **kwargs)
    sys.exit(1)


def get_number(prompt, **kwargs):
    default = kwargs.get('default', None)
    abort = kwargs.get('abort', None)

    if default is not None and abort is not None:
        prompt += ' (default is %s, %s to abort) ' % (default, abort)
    elif default is not None:
        prompt += ' (default is %s) ' % default
    elif abort is not None:
        prompt += ' (%s to abort) ' % abort

    number = None
    while number is None:
        msg(prompt, newline=False)
        ans = input()
        if ans == str(abort):
            return None

        if ans:
            try:
                number = int(ans)
                if number < 1:
                    msg("Please enter a valid number.")
                    number = None
            except ValueError:
                msg("Please enter a valid number.")
        elif default is not None:
            number = default
    return number


def get_yes_or_no(prompt, **kwargs):
    default_value = kwargs.get('default', None)

    if default_value is None:
        prompt += ' [y/n] '
    elif default_value is True:
        prompt += ' [Y/n] '
    elif default_value is False:
        prompt += ' [y/N] '
    else:
        raise ValueError(
            "default for get_yes_no() must be True, False, or None.")

    result = None
    while result is None:
        msg(prompt, newline=False)
        ans = input().lower()
        if not ans:
            result = default_value
            if result is None:
                print("Please enter yes or no.")
        else:
            if ans == 'y' or ans == 'yes':
                result = True
            elif ans == 'n' or ans == 'no':
                result = False
    return result


def hline(label=None, **kwargs):
    """Draw a labeled horizontal line.

    Keyword Arguments:
        char (str): Char to draw the line with.  Default '-'
        max_width (int): Maximum width of the line.  Default is 64 chars.
    """
    char = kwargs.pop('char', '-')
    max_width = kwargs.pop('max_width', 64)
    if kwargs:
        raise TypeError(
            "'%s' is an invalid keyword argument for this function."
            % next(kwargs.iterkeys()))

    rows, cols = terminal_size()
    if not cols:
        cols = max_width
    else:
        cols -= 2
    cols = min(max_width, cols)

    label = str(label)
    prefix = char * 2 + " "
    suffix = " " + (cols - len(prefix) - clen(label)) * char

    out = StringIO()
    out.write(prefix)
    out.write(label)
    out.write(suffix)

    print(out.getvalue())


def terminal_size():
    """Gets the dimensions of the console: (rows, cols)."""
    def ioctl_gwinsz(fd):
        try:
            rc = struct.unpack('hh', fcntl.ioctl(
                fd, termios.TIOCGWINSZ, '1234'))
        except BaseException:
            return
        return rc
    rc = ioctl_gwinsz(0) or ioctl_gwinsz(1) or ioctl_gwinsz(2)
    if not rc:
        try:
            fd = os.open(os.ctermid(), os.O_RDONLY)
            rc = ioctl_gwinsz(fd)
            os.close(fd)
        except BaseException:
            pass
    if not rc:
        rc = (os.environ.get('LINES', 25), os.environ.get('COLUMNS', 80))

    return int(rc[0]), int(rc[1])
