import base64
import json
import os
import os.path
import shlex
import string
from datetime import datetime
from distutils.version import StrictVersion

from .. import errors
from .. import tls
from ..constants import DEFAULT_HTTP_HOST
from ..constants import DEFAULT_UNIX_SOCKET
from ..constants import DEFAULT_NPIPE
from ..constants import BYTE_UNITS

from urllib.parse import splitnport, urlparse


def create_ipam_pool(*args, **kwargs):
    raise errors.DeprecatedMethod(
        'utils.create_ipam_pool has been removed. Please use a '
        'docker.types.IPAMPool object instead.'
    )


def create_ipam_config(*args, **kwargs):
    raise errors.DeprecatedMethod(
        'utils.create_ipam_config has been removed. Please use a '
        'docker.types.IPAMConfig object instead.'
    )


def decode_json_header(header):
    data = base64.b64decode(header)
    data = data.decode('utf-8')
    return json.loads(data)


def compare_version(v1, v2):
    """Compare docker versions

    >>> v1 = '1.9'
    >>> v2 = '1.10'
    >>> compare_version(v1, v2)
    1
    >>> compare_version(v2, v1)
    -1
    >>> compare_version(v2, v2)
    0
    """
    s1 = StrictVersion(v1)
    s2 = StrictVersion(v2)
    if s1 == s2:
        return 0
    elif s1 > s2:
        return -1
    else:
        return 1


def version_lt(v1, v2):
    return compare_version(v1, v2) > 0


def version_gte(v1, v2):
    return not version_lt(v1, v2)


def _convert_port_binding(binding):
    result = {'HostIp': '', 'HostPort': ''}
    if isinstance(binding, tuple):
        if len(binding) == 2:
            result['HostPort'] = binding[1]
            result['HostIp'] = binding[0]
        elif isinstance(binding[0], str):
            result['HostIp'] = binding[0]
        else:
            result['HostPort'] = binding[0]
    elif isinstance(binding, dict):
        if 'HostPort' in binding:
            result['HostPort'] = binding['HostPort']
            if 'HostIp' in binding:
                result['HostIp'] = binding['HostIp']
        else:
            raise ValueError(binding)
    else:
        result['HostPort'] = binding

    if result['HostPort'] is None:
        result['HostPort'] = ''
    else:
        result['HostPort'] = str(result['HostPort'])

    return result


def convert_port_bindings(port_bindings):
    result = {}
    for k, v in iter(port_bindings.items()):
        key = str(k)
        if '/' not in key:
            key += '/tcp'
        if isinstance(v, list):
            result[key] = [_convert_port_binding(binding) for binding in v]
        else:
            result[key] = [_convert_port_binding(v)]
    return result


def convert_volume_binds(binds):
    if isinstance(binds, list):
        return binds

    result = []
    for k, v in binds.items():
        if isinstance(k, bytes):
            k = k.decode('utf-8')

        if isinstance(v, dict):
            if 'ro' in v and 'mode' in v:
                raise ValueError(
                    'Binding cannot contain both "ro" and "mode": {}'
                    .format(repr(v))
                )

            bind = v['bind']
            if isinstance(bind, bytes):
                bind = bind.decode('utf-8')

            if 'ro' in v:
                mode = 'ro' if v['ro'] else 'rw'
            elif 'mode' in v:
                mode = v['mode']
            else:
                mode = 'rw'

            result.append(
                str('{0}:{1}:{2}').format(k, bind, mode)
            )
        else:
            if isinstance(v, bytes):
                v = v.decode('utf-8')
            result.append(
                str('{0}:{1}:rw').format(k, v)
            )
    return result


def convert_tmpfs_mounts(tmpfs):
    if isinstance(tmpfs, dict):
        return tmpfs

    if not isinstance(tmpfs, list):
        raise ValueError(
            'Expected tmpfs value to be either a list or a dict, found: {}'
            .format(type(tmpfs).__name__)
        )

    result = {}
    for mount in tmpfs:
        if isinstance(mount, str):
            if ":" in mount:
                name, options = mount.split(":", 1)
            else:
                name = mount
                options = ""

        else:
            raise ValueError(
                "Expected item in tmpfs list to be a string, found: {}"
                .format(type(mount).__name__)
            )

        result[name] = options
    return result


def convert_service_networks(networks):
    if not networks:
        return networks
    if not isinstance(networks, list):
        raise TypeError('networks parameter must be a list.')

    result = []
    for n in networks:
        if isinstance(n, str):
            n = {'Target': n}
        result.append(n)
    return result


def parse_repository_tag(repo_name):
    parts = repo_name.rsplit('@', 1)
    if len(parts) == 2:
        return tuple(parts)
    parts = repo_name.rsplit(':', 1)
    if len(parts) == 2 and '/' not in parts[1]:
        return tuple(parts)
    return repo_name, None


def parse_host(addr, is_win32=False, tls=False):
    path = ''
    port = None
    host = None

    # Sensible defaults
    if not addr and is_win32:
        return DEFAULT_NPIPE
    if not addr or addr.strip() == 'unix://':
        return DEFAULT_UNIX_SOCKET

    addr = addr.strip()

    parsed_url = urlparse(addr)
    proto = parsed_url.scheme
    if not proto or any([x not in string.ascii_letters + '+' for x in proto]):
        # https://bugs.python.org/issue754016
        parsed_url = urlparse('//' + addr, 'tcp')
        proto = 'tcp'

    if proto == 'fd':
        raise errors.DockerException('fd protocol is not implemented')

    # These protos are valid aliases for our library but not for the
    # official spec
    if proto == 'http' or proto == 'https':
        tls = proto == 'https'
        proto = 'tcp'
    elif proto == 'http+unix':
        proto = 'unix'

    if proto not in ('tcp', 'unix', 'npipe', 'ssh'):
        raise errors.DockerException(
            "Invalid bind address protocol: {}".format(addr)
        )

    if proto == 'tcp' and not parsed_url.netloc:
        # "tcp://" is exceptionally disallowed by convention;
        # omitting a hostname for other protocols is fine
        raise errors.DockerException(
            'Invalid bind address format: {}'.format(addr)
        )

    if any([
        parsed_url.params, parsed_url.query, parsed_url.fragment,
        parsed_url.password
    ]):
        raise errors.DockerException(
            'Invalid bind address format: {}'.format(addr)
        )

    if parsed_url.path and proto == 'ssh':
        raise errors.DockerException(
            'Invalid bind address format: no path allowed for this protocol:'
            ' {}'.format(addr)
        )
    else:
        path = parsed_url.path
        if proto == 'unix' and parsed_url.hostname is not None:
            # For legacy reasons, we consider unix://path
            # to be valid and equivalent to unix:///path
            path = '/'.join((parsed_url.hostname, path))

    if proto in ('tcp', 'ssh'):
        # parsed_url.hostname strips brackets from IPv6 addresses,
        # which can be problematic hence our use of splitnport() instead.
        host, port = splitnport(parsed_url.netloc)
        if port is None or port < 0:
            if proto != 'ssh':
                raise errors.DockerException(
                    'Invalid bind address format: port is required:'
                    ' {}'.format(addr)
                )
            port = 22

        if not host:
            host = DEFAULT_HTTP_HOST

    # Rewrite schemes to fit library internals (requests adapters)
    if proto == 'tcp':
        proto = 'http{}'.format('s' if tls else '')
    elif proto == 'unix':
        proto = 'http+unix'

    if proto in ('http+unix', 'npipe'):
        return "{}://{}".format(proto, path).rstrip('/')
    return '{0}://{1}:{2}{3}'.format(proto, host, port, path).rstrip('/')


def parse_devices(devices):
    device_list = []
    for device in devices:
        if isinstance(device, dict):
            device_list.append(device)
            continue
        if not isinstance(device, str):
            raise errors.DockerException(
                'Invalid device type {0}'.format(type(device))
            )
        device_mapping = device.split(':')
        if device_mapping:
            path_on_host = device_mapping[0]
            if len(device_mapping) > 1:
                path_in_container = device_mapping[1]
            else:
                path_in_container = path_on_host
            if len(device_mapping) > 2:
                permissions = device_mapping[2]
            else:
                permissions = 'rwm'
            device_list.append({
                'PathOnHost': path_on_host,
                'PathInContainer': path_in_container,
                'CgroupPermissions': permissions
            })
    return device_list


def kwargs_from_env(ssl_version=None, assert_hostname=None, environment=None):
    if not environment:
        environment = os.environ
    host = environment.get('DOCKER_HOST')

    # empty string for cert path is the same as unset.
    cert_path = environment.get('DOCKER_CERT_PATH') or None

    # empty string for tls verify counts as "false".
    # Any value or 'unset' counts as true.
    tls_verify = environment.get('DOCKER_TLS_VERIFY')
    if tls_verify == '':
        tls_verify = False
    else:
        tls_verify = tls_verify is not None
    enable_tls = cert_path or tls_verify

    params = {}

    if host:
        params['base_url'] = host

    if not enable_tls:
        return params

    if not cert_path:
        cert_path = os.path.join(os.path.expanduser('~'), '.docker')

    if not tls_verify and assert_hostname is None:
        # assert_hostname is a subset of TLS verification,
        # so if it's not set already then set it to false.
        assert_hostname = False

    params['tls'] = tls.TLSConfig(
        client_cert=(os.path.join(cert_path, 'cert.pem'),
                     os.path.join(cert_path, 'key.pem')),
        ca_cert=os.path.join(cert_path, 'ca.pem'),
        verify=tls_verify,
        ssl_version=ssl_version,
        assert_hostname=assert_hostname,
    )

    return params


def convert_filters(filters):
    result = {}
    for k, v in iter(filters.items()):
        if isinstance(v, bool):
            v = 'true' if v else 'false'
        if not isinstance(v, list):
            v = [v, ]
        result[k] = [
            str(item) if not isinstance(item, str) else item
            for item in v
        ]
    return json.dumps(result)


def datetime_to_timestamp(dt):
    """Convert a UTC datetime to a Unix timestamp"""
    delta = dt - datetime.utcfromtimestamp(0)
    return delta.seconds + delta.days * 24 * 3600


def parse_bytes(s):
    if isinstance(s, (int, float,)):
        return s
    if len(s) == 0:
        return 0

    if s[-2:-1].isalpha() and s[-1].isalpha():
        if s[-1] == "b" or s[-1] == "B":
            s = s[:-1]
    units = BYTE_UNITS
    suffix = s[-1].lower()

    # Check if the variable is a string representation of an int
    # without a units part. Assuming that the units are bytes.
    if suffix.isdigit():
        digits_part = s
        suffix = 'b'
    else:
        digits_part = s[:-1]

    if suffix in units.keys() or suffix.isdigit():
        try:
            digits = float(digits_part)
        except ValueError:
            raise errors.DockerException(
                'Failed converting the string value for memory ({0}) to'
                ' an integer.'.format(digits_part)
            )

        # Reconvert to long for the final result
        s = int(digits * units[suffix])
    else:
        raise errors.DockerException(
            'The specified value for memory ({0}) should specify the'
            ' units. The postfix should be one of the `b` `k` `m` `g`'
            ' characters'.format(s)
        )

    return s


def normalize_links(links):
    if isinstance(links, dict):
        links = iter(links.items())

    return ['{0}:{1}'.format(k, v) if v else k for k, v in sorted(links)]


def parse_env_file(env_file):
    """
    Reads a line-separated environment file.
    The format of each line should be "key=value".
    """
    environment = {}

    with open(env_file, 'r') as f:
        for line in f:

            if line[0] == '#':
                continue

            line = line.strip()
            if not line:
                continue

            parse_line = line.split('=', 1)
            if len(parse_line) == 2:
                k, v = parse_line
                environment[k] = v
            else:
                raise errors.DockerException(
                    'Invalid line in environment file {0}:\n{1}'.format(
                        env_file, line))

    return environment


def split_command(command):
    return shlex.split(command)


def format_environment(environment):
    def format_env(key, value):
        if value is None:
            return key
        if isinstance(value, bytes):
            value = value.decode('utf-8')

        return u'{key}={value}'.format(key=key, value=value)
    return [format_env(*var) for var in iter(environment.items())]


def format_extra_hosts(extra_hosts, task=False):
    # Use format dictated by Swarm API if container is part of a task
    if task:
        return [
            '{} {}'.format(v, k) for k, v in sorted(iter(extra_hosts.items()))
        ]

    return [
        '{}:{}'.format(k, v) for k, v in sorted(iter(extra_hosts.items()))
    ]


def create_host_config(self, *args, **kwargs):
    raise errors.DeprecatedMethod(
        'utils.create_host_config has been removed. Please use a '
        'docker.types.HostConfig object instead.'
    )