"""Miscellaneous utility functions and classes."""

from __future__ import absolute_import, print_function

import atexit
import contextlib
import errno
import fcntl
import inspect
import json
import os
import pipes
import pkgutil
import random
import re
import shutil
import socket
import stat
import string
import subprocess
import sys
import tempfile
import time

from struct import unpack, pack
from termios import TIOCGWINSZ

try:
    from abc import ABC
except ImportError:
    from abc import ABCMeta
    ABC = ABCMeta('ABC', (), {})

try:
    # noinspection PyCompatibility
    from ConfigParser import SafeConfigParser as ConfigParser
except ImportError:
    # noinspection PyCompatibility
    from configparser import ConfigParser

DOCKER_COMPLETION = {}
COVERAGE_PATHS = {}  # type: dict[str, str]

try:
    MAXFD = subprocess.MAXFD
except AttributeError:
    MAXFD = -1


def get_docker_completion():
    """
    :rtype: dict[str, str]
    """
    if not DOCKER_COMPLETION:
        images = read_lines_without_comments('test/runner/completion/docker.txt', remove_blank_lines=True)

        DOCKER_COMPLETION.update(dict(kvp for kvp in [parse_docker_completion(i) for i in images] if kvp))

    return DOCKER_COMPLETION


def parse_docker_completion(value):
    """
    :type value: str
    :rtype: tuple[str, dict[str, str]]
    """
    values = value.split()

    if not values:
        return None

    name = values[0]
    data = dict((kvp[0], kvp[1] if len(kvp) > 1 else '') for kvp in [item.split('=', 1) for item in values[1:]])

    return name, data


def is_shippable():
    """
    :rtype: bool
    """
    return os.environ.get('SHIPPABLE') == 'true'


def remove_file(path):
    """
    :type path: str
    """
    if os.path.isfile(path):
        os.remove(path)


def read_lines_without_comments(path, remove_blank_lines=False):
    """
    :type path: str
    :type remove_blank_lines: bool
    :rtype: list[str]
    """
    with open(path, 'r') as path_fd:
        lines = path_fd.read().splitlines()

    lines = [re.sub(r' *#.*$', '', line) for line in lines]

    if remove_blank_lines:
        lines = [line for line in lines if line]

    return lines


def find_executable(executable, cwd=None, path=None, required=True):
    """
    :type executable: str
    :type cwd: str
    :type path: str
    :type required: bool | str
    :rtype: str | None
    """
    match = None
    real_cwd = os.getcwd()

    if not cwd:
        cwd = real_cwd

    if os.path.dirname(executable):
        target = os.path.join(cwd, executable)
        if os.path.exists(target) and os.access(target, os.F_OK | os.X_OK):
            match = executable
    else:
        if path is None:
            path = os.environ.get('PATH', os.path.defpath)

        if path:
            path_dirs = path.split(os.path.pathsep)
            seen_dirs = set()

            for path_dir in path_dirs:
                if path_dir in seen_dirs:
                    continue

                seen_dirs.add(path_dir)

                if os.path.abspath(path_dir) == real_cwd:
                    path_dir = cwd

                candidate = os.path.join(path_dir, executable)

                if os.path.exists(candidate) and os.access(candidate, os.F_OK | os.X_OK):
                    match = candidate
                    break

    if not match and required:
        message = 'Required program "%s" not found.' % executable

        if required != 'warning':
            raise ApplicationError(message)

        display.warning(message)

    return match


def find_python(version, path=None):
    """
    :type version: str
    :type path: str | None
    :rtype: str
    """
    version_info = tuple(int(n) for n in version.split('.'))

    if not path and version_info == sys.version_info[:len(version_info)]:
        python_bin = sys.executable
    else:
        python_bin = find_executable('python%s' % version, path=path)

    return python_bin


def generate_pip_command(python):
    """
    :type python: str
    :rtype: list[str]
    """
    return [python, '-m', 'pip.__main__']


def intercept_command(args, cmd, target_name, capture=False, env=None, data=None, cwd=None, python_version=None, path=None, coverage=None):
    """
    :type args: TestConfig
    :type cmd: collections.Iterable[str]
    :type target_name: str
    :type capture: bool
    :type env: dict[str, str] | None
    :type data: str | None
    :type cwd: str | None
    :type python_version: str | None
    :type path: str | None
    :type coverage: bool | None
    :rtype: str | None, str | None
    """
    if not env:
        env = common_environment()

    if coverage is None:
        coverage = args.coverage

    cmd = list(cmd)
    version = python_version or args.python_version
    interpreter = find_python(version, path)
    inject_path = get_coverage_path(args, interpreter)
    config_path = os.path.join(inject_path, 'injector.json')
    coverage_file = os.path.abspath(os.path.join(inject_path, '..', 'output', '%s=%s=%s=%s=coverage' % (
        args.command, target_name, args.coverage_label or 'local-%s' % version, 'python-%s' % version)))

    if args.coverage_check:
        coverage_file = ''

    env['PATH'] = inject_path + os.path.pathsep + env['PATH']
    env['ANSIBLE_TEST_PYTHON_VERSION'] = version
    env['ANSIBLE_TEST_PYTHON_INTERPRETER'] = interpreter

    if coverage:
        env['_ANSIBLE_COVERAGE_CONFIG'] = os.path.join(inject_path, '.coveragerc')
        env['_ANSIBLE_COVERAGE_OUTPUT'] = coverage_file

    config = dict(
        python_interpreter=interpreter,
        coverage_file=coverage_file if coverage else None,
    )

    if not args.explain:
        with open(config_path, 'w') as config_fd:
            json.dump(config, config_fd, indent=4, sort_keys=True)

    return run_command(args, cmd, capture=capture, env=env, data=data, cwd=cwd)


def get_coverage_path(args, interpreter):
    """
    :type args: TestConfig
    :type interpreter: str
    :rtype: str
    """
    coverage_path = COVERAGE_PATHS.get(interpreter)

    if coverage_path:
        return os.path.join(coverage_path, 'coverage')

    prefix = 'ansible-test-coverage-'
    tmp_dir = '/tmp'

    if args.explain:
        return os.path.join(tmp_dir, '%stmp' % prefix, 'coverage')

    src = os.path.abspath(os.path.join(os.getcwd(), 'test/runner/injector/'))

    coverage_path = tempfile.mkdtemp('', prefix, dir=tmp_dir)
    os.chmod(coverage_path, stat.S_IRWXU | stat.S_IRGRP | stat.S_IXGRP | stat.S_IROTH | stat.S_IXOTH)

    shutil.copytree(src, os.path.join(coverage_path, 'coverage'))
    shutil.copy('.coveragerc', os.path.join(coverage_path, 'coverage', '.coveragerc'))

    for root, dir_names, file_names in os.walk(coverage_path):
        for name in dir_names + file_names:
            os.chmod(os.path.join(root, name), stat.S_IRWXU | stat.S_IRGRP | stat.S_IXGRP | stat.S_IROTH | stat.S_IXOTH)

    for directory in 'output', 'logs':
        os.mkdir(os.path.join(coverage_path, directory))
        os.chmod(os.path.join(coverage_path, directory), stat.S_IRWXU | stat.S_IRWXG | stat.S_IRWXO)

    os.symlink(interpreter, os.path.join(coverage_path, 'coverage', 'python'))

    if not COVERAGE_PATHS:
        atexit.register(cleanup_coverage_dirs)

    COVERAGE_PATHS[interpreter] = coverage_path

    return os.path.join(coverage_path, 'coverage')


def cleanup_coverage_dirs():
    """Clean up all coverage directories."""
    for path in COVERAGE_PATHS.values():
        display.info('Cleaning up coverage directory: %s' % path, verbosity=2)
        cleanup_coverage_dir(path)


def cleanup_coverage_dir(coverage_path):
    """Copy over coverage data from temporary directory and purge temporary directory.
    :type coverage_path: str
    """
    output_dir = os.path.join(coverage_path, 'output')

    for filename in os.listdir(output_dir):
        src = os.path.join(output_dir, filename)
        dst = os.path.join(os.getcwd(), 'test', 'results', 'coverage')
        shutil.copy(src, dst)

    logs_dir = os.path.join(coverage_path, 'logs')

    for filename in os.listdir(logs_dir):
        random_suffix = ''.join(random.choice(string.ascii_letters + string.digits) for _ in range(8))
        new_name = '%s.%s.log' % (os.path.splitext(os.path.basename(filename))[0], random_suffix)
        src = os.path.join(logs_dir, filename)
        dst = os.path.join(os.getcwd(), 'test', 'results', 'logs', new_name)
        shutil.copy(src, dst)

    shutil.rmtree(coverage_path)


def run_command(args, cmd, capture=False, env=None, data=None, cwd=None, always=False, stdin=None, stdout=None,
                cmd_verbosity=1, str_errors='strict'):
    """
    :type args: CommonConfig
    :type cmd: collections.Iterable[str]
    :type capture: bool
    :type env: dict[str, str] | None
    :type data: str | None
    :type cwd: str | None
    :type always: bool
    :type stdin: file | None
    :type stdout: file | None
    :type cmd_verbosity: int
    :type str_errors: str
    :rtype: str | None, str | None
    """
    explain = args.explain and not always
    return raw_command(cmd, capture=capture, env=env, data=data, cwd=cwd, explain=explain, stdin=stdin, stdout=stdout,
                       cmd_verbosity=cmd_verbosity, str_errors=str_errors)


def raw_command(cmd, capture=False, env=None, data=None, cwd=None, explain=False, stdin=None, stdout=None,
                cmd_verbosity=1, str_errors='strict'):
    """
    :type cmd: collections.Iterable[str]
    :type capture: bool
    :type env: dict[str, str] | None
    :type data: str | None
    :type cwd: str | None
    :type explain: bool
    :type stdin: file | None
    :type stdout: file | None
    :type cmd_verbosity: int
    :type str_errors: str
    :rtype: str | None, str | None
    """
    if not cwd:
        cwd = os.getcwd()

    if not env:
        env = common_environment()

    cmd = list(cmd)

    escaped_cmd = ' '.join(pipes.quote(c) for c in cmd)

    display.info('Run command: %s' % escaped_cmd, verbosity=cmd_verbosity, truncate=True)
    display.info('Working directory: %s' % cwd, verbosity=2)

    program = find_executable(cmd[0], cwd=cwd, path=env['PATH'], required='warning')

    if program:
        display.info('Program found: %s' % program, verbosity=2)

    for key in sorted(env.keys()):
        display.info('%s=%s' % (key, env[key]), verbosity=2)

    if explain:
        return None, None

    communicate = False

    if stdin is not None:
        data = None
        communicate = True
    elif data is not None:
        stdin = subprocess.PIPE
        communicate = True

    if stdout:
        communicate = True

    if capture:
        stdout = stdout or subprocess.PIPE
        stderr = subprocess.PIPE
        communicate = True
    else:
        stderr = None

    start = time.time()
    process = None

    try:
        try:
            process = subprocess.Popen(cmd, env=env, stdin=stdin, stdout=stdout, stderr=stderr, cwd=cwd)
        except OSError as ex:
            if ex.errno == errno.ENOENT:
                raise ApplicationError('Required program "%s" not found.' % cmd[0])
            raise

        if communicate:
            encoding = 'utf-8'
            data_bytes = data.encode(encoding, 'surrogateescape') if data else None
            stdout_bytes, stderr_bytes = process.communicate(data_bytes)
            stdout_text = stdout_bytes.decode(encoding, str_errors) if stdout_bytes else u''
            stderr_text = stderr_bytes.decode(encoding, str_errors) if stderr_bytes else u''
        else:
            process.wait()
            stdout_text, stderr_text = None, None
    finally:
        if process and process.returncode is None:
            process.kill()
            display.info('')  # the process we're interrupting may have completed a partial line of output
            display.notice('Killed command to avoid an orphaned child process during handling of an unexpected exception.')

    status = process.returncode
    runtime = time.time() - start

    display.info('Command exited with status %s after %s seconds.' % (status, runtime), verbosity=4)

    if status == 0:
        return stdout_text, stderr_text

    raise SubprocessError(cmd, status, stdout_text, stderr_text, runtime)


def common_environment():
    """Common environment used for executing all programs."""
    env = dict(
        LC_ALL='en_US.UTF-8',
        PATH=os.environ.get('PATH', os.path.defpath),
    )

    required = (
        'HOME',
    )

    optional = (
        'HTTPTESTER',
        'LD_LIBRARY_PATH',
        'SSH_AUTH_SOCK',
        # MacOS High Sierra Compatibility
        # http://sealiesoftware.com/blog/archive/2017/6/5/Objective-C_and_fork_in_macOS_1013.html
        'OBJC_DISABLE_INITIALIZE_FORK_SAFETY',
        'ANSIBLE_KEEP_REMOTE_FILES',
    )

    env.update(pass_vars(required=required, optional=optional))

    return env


def pass_vars(required, optional):
    """
    :type required: collections.Iterable[str]
    :type optional: collections.Iterable[str]
    :rtype: dict[str, str]
    """
    env = {}

    for name in required:
        if name not in os.environ:
            raise MissingEnvironmentVariable(name)
        env[name] = os.environ[name]

    for name in optional:
        if name not in os.environ:
            continue
        env[name] = os.environ[name]

    return env


def deepest_path(path_a, path_b):
    """Return the deepest of two paths, or None if the paths are unrelated.
    :type path_a: str
    :type path_b: str
    :rtype: str | None
    """
    if path_a == '.':
        path_a = ''

    if path_b == '.':
        path_b = ''

    if path_a.startswith(path_b):
        return path_a or '.'

    if path_b.startswith(path_a):
        return path_b or '.'

    return None


def remove_tree(path):
    """
    :type path: str
    """
    try:
        shutil.rmtree(path)
    except OSError as ex:
        if ex.errno != errno.ENOENT:
            raise


def make_dirs(path):
    """
    :type path: str
    """
    try:
        os.makedirs(path)
    except OSError as ex:
        if ex.errno != errno.EEXIST:
            raise


def is_binary_file(path):
    """
    :type path: str
    :rtype: bool
    """
    assume_text = set([
        '.cfg',
        '.conf',
        '.crt',
        '.cs',
        '.css',
        '.html',
        '.ini',
        '.j2',
        '.js',
        '.json',
        '.md',
        '.pem',
        '.ps1',
        '.psm1',
        '.py',
        '.rst',
        '.sh',
        '.txt',
        '.xml',
        '.yaml',
        '.yml',
    ])

    assume_binary = set([
        '.bin',
        '.eot',
        '.gz',
        '.ico',
        '.iso',
        '.jpg',
        '.otf',
        '.p12',
        '.png',
        '.pyc',
        '.rpm',
        '.ttf',
        '.woff',
        '.woff2',
        '.zip',
    ])

    ext = os.path.splitext(path)[1]

    if ext in assume_text:
        return False

    if ext in assume_binary:
        return True

    with open(path, 'rb') as path_fd:
        return b'\0' in path_fd.read(1024)


def generate_password():
    """Generate a random password.
    :rtype: str
    """
    chars = [
        string.ascii_letters,
        string.digits,
        string.ascii_letters,
        string.digits,
        '-',
    ] * 4

    password = ''.join([random.choice(char) for char in chars[:-1]])

    display.sensitive.add(password)

    return password


class Display(object):
    """Manages color console output."""
    clear = '\033[0m'
    red = '\033[31m'
    green = '\033[32m'
    yellow = '\033[33m'
    blue = '\033[34m'
    purple = '\033[35m'
    cyan = '\033[36m'

    verbosity_colors = {
        0: None,
        1: green,
        2: blue,
        3: cyan,
    }

    def __init__(self):
        self.verbosity = 0
        self.color = True
        self.warnings = []
        self.warnings_unique = set()
        self.info_stderr = False
        self.rows = 0
        self.columns = 0
        self.truncate = 0
        self.redact = False
        self.sensitive = set()

        if os.isatty(0):
            self.rows, self.columns = unpack('HHHH', fcntl.ioctl(0, TIOCGWINSZ, pack('HHHH', 0, 0, 0, 0)))[:2]

    def __warning(self, message):
        """
        :type message: str
        """
        self.print_message('WARNING: %s' % message, color=self.purple, fd=sys.stderr)

    def review_warnings(self):
        """Review all warnings which previously occurred."""
        if not self.warnings:
            return

        self.__warning('Reviewing previous %d warning(s):' % len(self.warnings))

        for warning in self.warnings:
            self.__warning(warning)

    def warning(self, message, unique=False):
        """
        :type message: str
        :type unique: bool
        """
        if unique:
            if message in self.warnings_unique:
                return

            self.warnings_unique.add(message)

        self.__warning(message)
        self.warnings.append(message)

    def notice(self, message):
        """
        :type message: str
        """
        self.print_message('NOTICE: %s' % message, color=self.purple, fd=sys.stderr)

    def error(self, message):
        """
        :type message: str
        """
        self.print_message('ERROR: %s' % message, color=self.red, fd=sys.stderr)

    def info(self, message, verbosity=0, truncate=False):
        """
        :type message: str
        :type verbosity: int
        :type truncate: bool
        """
        if self.verbosity >= verbosity:
            color = self.verbosity_colors.get(verbosity, self.yellow)
            self.print_message(message, color=color, fd=sys.stderr if self.info_stderr else sys.stdout, truncate=truncate)

    def print_message(self, message, color=None, fd=sys.stdout, truncate=False):  # pylint: disable=locally-disabled, invalid-name
        """
        :type message: str
        :type color: str | None
        :type fd: file
        :type truncate: bool
        """
        if self.redact and self.sensitive:
            for item in self.sensitive:
                message = message.replace(item, '*' * len(item))

        if truncate:
            if len(message) > self.truncate > 5:
                message = message[:self.truncate - 5] + ' ...'

        if color and self.color:
            # convert color resets in message to desired color
            message = message.replace(self.clear, color)
            message = '%s%s%s' % (color, message, self.clear)

        if sys.version_info[0] == 2 and isinstance(message, type(u'')):
            message = message.encode('utf-8')

        print(message, file=fd)
        fd.flush()


class ApplicationError(Exception):
    """General application error."""
    pass


class ApplicationWarning(Exception):
    """General application warning which interrupts normal program flow."""
    pass


class SubprocessError(ApplicationError):
    """Error resulting from failed subprocess execution."""
    def __init__(self, cmd, status=0, stdout=None, stderr=None, runtime=None):
        """
        :type cmd: list[str]
        :type status: int
        :type stdout: str | None
        :type stderr: str | None
        :type runtime: float | None
        """
        message = 'Command "%s" returned exit status %s.\n' % (' '.join(pipes.quote(c) for c in cmd), status)

        if stderr:
            message += '>>> Standard Error\n'
            message += '%s%s\n' % (stderr.strip(), Display.clear)

        if stdout:
            message += '>>> Standard Output\n'
            message += '%s%s\n' % (stdout.strip(), Display.clear)

        message = message.strip()

        super(SubprocessError, self).__init__(message)

        self.cmd = cmd
        self.status = status
        self.stdout = stdout
        self.stderr = stderr
        self.runtime = runtime


class MissingEnvironmentVariable(ApplicationError):
    """Error caused by missing environment variable."""
    def __init__(self, name):
        """
        :type name: str
        """
        super(MissingEnvironmentVariable, self).__init__('Missing environment variable: %s' % name)

        self.name = name


class CommonConfig(object):
    """Configuration common to all commands."""
    def __init__(self, args, command):
        """
        :type args: any
        :type command: str
        """
        self.command = command

        self.color = args.color  # type: bool
        self.explain = args.explain  # type: bool
        self.verbosity = args.verbosity  # type: int
        self.debug = args.debug  # type: bool
        self.truncate = args.truncate  # type: int
        self.redact = args.redact  # type: bool

        if is_shippable():
            self.redact = True

        self.cache = {}


def docker_qualify_image(name):
    """
    :type name: str
    :rtype: str
    """
    config = get_docker_completion().get(name, {})

    return config.get('name', name)


@contextlib.contextmanager
def named_temporary_file(args, prefix, suffix, directory, content):
    """
    :param args: CommonConfig
    :param prefix: str
    :param suffix: str
    :param directory: str
    :param content: str | bytes | unicode
    :rtype: str
    """
    if not isinstance(content, bytes):
        content = content.encode('utf-8')

    if args.explain:
        yield os.path.join(directory, '%stemp%s' % (prefix, suffix))
    else:
        with tempfile.NamedTemporaryFile(prefix=prefix, suffix=suffix, dir=directory) as tempfile_fd:
            tempfile_fd.write(content)
            tempfile_fd.flush()

            yield tempfile_fd.name


def parse_to_list_of_dict(pattern, value):
    """
    :type pattern: str
    :type value: str
    :return: list[dict[str, str]]
    """
    matched = []
    unmatched = []

    for line in value.splitlines():
        match = re.search(pattern, line)

        if match:
            matched.append(match.groupdict())
        else:
            unmatched.append(line)

    if unmatched:
        raise Exception('Pattern "%s" did not match values:\n%s' % (pattern, '\n'.join(unmatched)))

    return matched


def get_available_port():
    """
    :rtype: int
    """
    # this relies on the kernel not reusing previously assigned ports immediately
    socket_fd = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

    with contextlib.closing(socket_fd):
        socket_fd.bind(('', 0))
        return socket_fd.getsockname()[1]


def get_subclasses(class_type):
    """
    :type class_type: type
    :rtype: set[str]
    """
    subclasses = set()
    queue = [class_type]

    while queue:
        parent = queue.pop()

        for child in parent.__subclasses__():
            if child not in subclasses:
                if not inspect.isabstract(child):
                    subclasses.add(child)
                queue.append(child)

    return subclasses


def import_plugins(directory):
    """
    :type directory: str
    """
    path = os.path.join(os.path.dirname(__file__), directory)
    prefix = 'lib.%s.' % directory

    for (_, name, _) in pkgutil.iter_modules([path], prefix=prefix):
        __import__(name)


def load_plugins(base_type, database):
    """
    :type base_type: type
    :type database: dict[str, type]
    """
    plugins = dict((sc.__module__.split('.')[2], sc) for sc in get_subclasses(base_type))  # type: dict [str, type]

    for plugin in plugins:
        database[plugin] = plugins[plugin]


display = Display()  # pylint: disable=locally-disabled, invalid-name