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

from __future__ import absolute_import, print_function

import atexit
import errno
import filecmp
import fcntl
import inspect
import json
import os
import pipes
import pkgutil
import random
import re
import shutil
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', (), {})

DOCKER_COMPLETION = {}

coverage_path = ''  # pylint: disable=locally-disabled, invalid-name


def get_docker_completion():
    """
    :rtype: dict[str, str]
    """
    if not DOCKER_COMPLETION:
        with open('test/runner/completion/docker.txt', 'r') as completion_fd:
            images = completion_fd.read().splitlines()

        DOCKER_COMPLETION.update(dict((i.split('@')[0], i) for i in images))

    return DOCKER_COMPLETION


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 find_pip(path=None, version=None):
    """
    :type path: str | None
    :type version: str | None
    :rtype: str
    """
    if version:
        version_info = version.split('.')
        python_bin = find_executable('python%s' % version, path=path)
    else:
        version_info = sys.version_info
        python_bin = sys.executable

    choices = (
        'pip%s' % '.'.join(str(i) for i in version_info[:2]),
        'pip%s' % version_info[0],
        'pip',
    )

    pip = None

    for choice in choices:
        pip = find_executable(choice, required=False, path=path)

        if pip:
            break

    if not pip:
        raise ApplicationError('Required program not found: %s' % ', '.join(choices))

    with open(pip) as pip_fd:
        shebang = pip_fd.readline().strip()

    if not shebang.startswith('#!') or ' ' in shebang:
        raise ApplicationError('Unexpected shebang in "%s": %s' % (pip, shebang))

    our_python = os.path.realpath(python_bin)
    pip_python = os.path.realpath(shebang[2:])

    if our_python != pip_python and not filecmp.cmp(our_python, pip_python, False):
        raise ApplicationError('Current interpreter "%s" does not match "%s" interpreter "%s".' % (our_python, pip, pip_python))

    return pip


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.defpath)

        if path:
            path_dirs = path.split(os.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 intercept_command(args, cmd, target_name, capture=False, env=None, data=None, cwd=None, python_version=None, path=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
    :rtype: str | None, str | None
    """
    if not env:
        env = common_environment()

    cmd = list(cmd)
    inject_path = get_coverage_path(args)
    config_path = os.path.join(inject_path, 'injector.json')
    version = python_version or args.python_version
    interpreter = find_executable('python%s' % version, path=path)
    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)))

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

    config = dict(
        python_interpreter=interpreter,
        coverage_file=coverage_file if args.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):
    """
    :type args: TestConfig
    :rtype: str
    """
    global coverage_path  # pylint: disable=locally-disabled, global-statement, invalid-name

    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)

    atexit.register(cleanup_coverage_dir)

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


def cleanup_coverage_dir():
    """Copy over coverage data from temporary directory and purge temporary directory."""
    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()

    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) 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

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


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):
        """
        :type args: any
        """
        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


def docker_qualify_image(name):
    """
    :type name: str
    :rtype: str
    """
    if not name or any((c in name) for c in ('/', ':')):
        return name

    name = get_docker_completion().get(name, name)

    return 'ansible/ansible:%s' % name


def parse_to_dict(pattern, value):
    """
    :type pattern: str
    :type value: str
    :return: dict[str, str]
    """
    match = re.search(pattern, value)

    if match is None:
        raise Exception('Pattern "%s" did not match value: %s' % (pattern, value))

    return match.groupdict()


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