import __main__
import argparse
import fileinput
import multiprocessing
import os
import re
import resource
import signal
import stat
import subprocess
import sys
import time
import types

from pybin import settings
from subprocess import Popen, PIPE, STDOUT

################################################################################
#               shell helpers
################################################################################

# helper functions to run terminal commands
def sh(cmd, print2stdout = True, timeout = False, output = None, input = None):
	# add input redirection if needed
	if input and os.path.isfile(input):
		cmd += " < %s" % input

	# add output redirection if needed
	if output:
		cmd += " > %s" % output

	# if this is a dry_run, only print the commands that would be ran
	if settings.dry_run :
		print("cmd: %s" % cmd)
		return 0, None

	# otherwise create a pipe and run the desired command
	else :
		try:
			proc = subprocess.run(
				cmd,
				stdout=None if print2stdout else PIPE,
				stderr=STDOUT,
				shell=True,
				timeout=settings.timeout.single if timeout else None
			)
			return proc.returncode, proc.stdout.decode("utf-8") if proc.stdout else None
		except subprocess.TimeoutExpired:
			return 124, str(None)

def is_ascii(fname):
	if settings.dry_run:
		print("is_ascii: %s" % fname)
		return True

	if not os.path.isfile(fname):
		return False

	code, out = sh("file %s" % fname, print2stdout = False)
	if code != 0:
		return False

	match = re.search(".*: (.*)", out)

	if not match:
		return False

	return match.group(1).startswith("ASCII text")

def is_exe(fname):
	return os.path.isfile(fname) and os.access(fname, os.X_OK)

# Remove 1 or more files silently
def rm( files ):
	if isinstance(files, str ): files = [ files ]
	for file in files:
		sh("rm -f %s > /dev/null 2>&1" % file )

# Create 1 or more directory
def mkdir( files ):
	if isinstance(files, str ): files = [ files ]
	for file in files:
		p = os.path.normpath( file )
		d = os.path.dirname ( p )
		sh( "mkdir -p {}".format(d) )


def chdir( dest = __main__.__file__ ):
	abspath = os.path.abspath(dest)
	dname = os.path.dirname(abspath)
	os.chdir(dname)

# diff two files
def diff( lhs, rhs ):
	# diff the output of the files
	diff_cmd = ("diff --text "
			"--old-group-format='\t\tmissing lines :\n"
			"%%<' \\\n"
			"--new-group-format='\t\tnew lines :\n"
			"%%>' \\\n"
			"--unchanged-group-format='%%=' \\"
			"--changed-group-format='\t\texpected :\n"
			"%%<"
			"\t\tgot :\n"
			"%%>\n' \\\n"
			"--new-line-format='\t\t%%dn\t%%L' \\\n"
			"--old-line-format='\t\t%%dn\t%%L' \\\n"
			"--unchanged-line-format='' \\\n"
			"%s %s")

	# fetch return code and error from the diff command
	return sh(diff_cmd % (lhs, rhs), False)

# call make
def make(target, flags = '', redirects = '', error_file = None, silent = False):
	test_param = """test="%s" """ % (error_file) if error_file else ''
	cmd = ' '.join([
		settings.make,
		'-s' if silent else '',
		test_param,
		settings.arch.flags,
		settings.debug.flags,
		settings.install.flags,
		flags,
		target,
		redirects
	])
	return sh(cmd)

def which(program):
    fpath, fname = os.path.split(program)
    if fpath:
        if is_exe(program):
            return program
    else:
        for path in os.environ["PATH"].split(os.pathsep):
            exe_file = os.path.join(path, program)
            if is_exe(exe_file):
                return exe_file

    return None

################################################################################
#               file handling
################################################################################
# move a file
def mv(source, dest):
	ret, _ = sh("mv %s %s" % (source, dest))
	return ret

# cat one file into the other
def cat(source, dest):
	ret, _ = sh("cat %s > %s" % (source, dest))
	return ret

# helper function to replace patterns in a file
def file_replace(fname, pat, s_after):
	if settings.dry_run:
		print("replacing '%s' with '%s' in %s" % (pat, s_after, fname))
		return

	file = fileinput.FileInput(fname, inplace=True, backup='.bak')
	for line in file:
		print(line.replace(pat, s_after), end='')
	file.close()

# helper function to check if a files contains only a specific string
def file_contains_only(file, text) :
	with open(file) as f:
		ff = f.read().strip()
		result = ff == text.strip()

		return result

# transform path to canonical form
def canonical_path(path):
	abspath = os.path.abspath(__main__.__file__)
	dname = os.path.dirname(abspath)
	return os.path.join(dname, os.path.normpath(path) )

# compare path even if form is different
def path_cmp(lhs, rhs):
	return canonical_path( lhs ) == canonical_path( rhs )

# walk all files in a path
def path_walk( op ):
	dname = settings.SRCDIR
	for dirname, _, names in os.walk(dname):
		for name in names:
			path = os.path.join(dirname, name)
			op( path )

################################################################################
#               system
################################################################################
# count number of jobs to create
def job_count( options, tests ):
	# check if the user already passed in a number of jobs for multi-threading
	if not options.jobs:
		make_flags = os.environ.get('MAKEFLAGS')
		force = bool(make_flags)
		make_jobs_fds = re.search("--jobserver-(auth|fds)=\s*([0-9]+),([0-9]+)", make_flags) if make_flags else None
		if make_jobs_fds :
			tokens = os.read(int(make_jobs_fds.group(2)), 1024)
			options.jobs = len(tokens)
			os.write(int(make_jobs_fds.group(3)), tokens)
		else :
			options.jobs = multiprocessing.cpu_count()
	else :
		force = True

	# make sure we have a valid number of jobs that corresponds to user input
	if options.jobs <= 0 :
		print('ERROR: Invalid number of jobs', file=sys.stderr)
		sys.exit(1)

	return min( options.jobs, len(tests) ), force

# enable core dumps for all the test children
resource.setrlimit(resource.RLIMIT_CORE, (resource.RLIM_INFINITY, resource.RLIM_INFINITY))

################################################################################
#               misc
################################################################################

# check if arguments is yes or no
def yes_no(string):
	if string == "yes" :
		return True
	if string == "no" :
		return False
	raise argparse.ArgumentTypeError(msg)

def fancy_print(text):
	column = which('column')
	if column:
		subprocess.run(column, input=bytes(text + "\n", "UTF-8"))
	else:
		print(text)


def core_info(path):
	cmd   = os.path.join(settings.SRCDIR, "pybin/print-core.gdb")
	if not os.path.isfile(cmd):
		return 1, "ERR Printing format for core dumps not found"

	dname = os.path.dirname(path)
	core  = os.path.join(dname, "core" )
	if not os.path.isfile(path):
		return 1, "ERR Executable path is wrong"

	if not os.path.isfile(core):
		return 1, "ERR No core dump"

	return sh("gdb -n %s %s -batch -x %s" % (path, core, cmd), print2stdout=False)

class Timed:
    def __enter__(self):
        self.start = time.time()
        return self

    def __exit__(self, *args):
        self.end = time.time()
        self.duration = self.end - self.start