# Copyright (c) 2015-2016 Tigera, Inc. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import copy
import os
import re
import socket
import sys
import tempfile
from datetime import datetime
from subprocess import CalledProcessError
from subprocess import check_output, STDOUT

import termios

import json
import logging
from pprint import pformat

import yaml
from deepdiff import DeepDiff

LOCAL_IP_ENV = "MY_IP"
LOCAL_IPv6_ENV = "MY_IPv6"
logger = logging.getLogger(__name__)

ETCD_SCHEME = os.environ.get("ETCD_SCHEME", "http")
ETCD_CA = os.environ.get("ETCD_CA_CERT_FILE", "")
ETCD_CERT = os.environ.get("ETCD_CERT_FILE", "")
ETCD_KEY = os.environ.get("ETCD_KEY_FILE", "")
ETCD_HOSTNAME_SSL = "etcd-authority-ssl"
KUBECONFIG = "/home/user/certs/kubeconfig"

API_VERSION = 'projectcalico.org/v3'
ERROR_CONFLICT = "update conflict"
NOT_FOUND = "resource does not exist"
NOT_NAMESPACED = "is not namespaced"
SET_DEFAULT = "Cannot set"
NOT_SUPPORTED = "is not supported on"
KUBERNETES_NP = "kubernetes network policies must be managed through the kubernetes API"
NOT_LOCKED = "Datastore is not locked. Run the `calicoctl datastore migrate lock` command in order to begin migration."
NOT_KUBERNETES = "Invalid datastore type: etcdv3 to import to for datastore migration. Datastore type must be kubernetes"
NO_IPAM = "No IPAM resources specified in file"
NOT_LOCKED_SPLIT = "Datastore is not locked. Run the `calicoctl datastore migrate lock` command in order split the IP pools."
POOL_NOT_EXIST_CIDR = "Unable to find IP pool"
INVALID_SPLIT_NUM = "Number to split CIDR into is not a valid power of 2"
POOL_TOO_SMALL = "is not large enough to be split into"

class CalicoctlOutput:
    """
    CalicoctlOutput contains the output from running a calicoctl command using
    the calicoctl function below.

    This class contains the command, output and error code (if it failed)
    along with YAML/JSON decoded output if the output could be decoded.
    """
    def __init__(self, command, output, error=None):
        self.command = command
        self.output = output
        self.error = error

        # Attempt to decode the output and store the output format.
        self.decoded, self.decoded_format = decode_json_yaml(self.output)

    def assert_data(self, data, format="yaml", text=None):
        """
        Assert the decoded output from the calicoctl command matches the
        supplied data and the expected decoder format.
        Args:
            data:   The data to compare
            format: The expected output format of the data.
            text:   (optional) Expected text in the command output.
        """
        self.assert_no_error(text)
        assert self.decoded is not None, "No value was decoded from calicoctl response."
        if isinstance(data, str):
            data, _ = decode_json_yaml(data)
            assert data is not None, "String data did not decode"

        if format is not None:
            assert format == self.decoded_format, "Decoded format is different. " \
                "expect %s; got %s" % (format, self.decoded_format)

        # Copy and clean the decoded data to allow it to be comparable.
        cleaned = clean_calico_data(self.decoded)

        assert cmp(cleaned, data) == 0, \
            "Items are not the same.  Difference is:\n %s" % \
            pformat(DeepDiff(cleaned, data), indent=2)

    def assert_empty_list(self, kind, format="yaml", text=None):
        """
        Assert the calicoctl command output an empty list of the specified
        kind.

        Args:
            kind:   The resource kind.
            format: The expected output format of the data.
            text:   (optional) Expected text in the command output.

        Returns:

        """
        data = make_list(kind, [])
        self.assert_data(data, format=format, text=text)

    def assert_list(self, kind, items, format="yaml", text=None):
        """
        Assert the calicoctl command output a list of the specified
        kind.

        Args:
            kind:   The resource kind.
            items:  A list of the items in the list.
            format: The expected output format of the data.
            text:   (optional) Expected text in the command output.

        Returns:

        """
        data = make_list(kind, items)
        self.assert_data(data, format=format, text=text)

    def assert_error(self, text=None):
        """
        Assert the calicoctl command exited with an error and did not panic
        Args:
            text:   (optional) Expected text in the command output.
        """
        assert self.error, "Expected error running command; \n" \
            "command=" + self.command + "\noutput=" + self.output
        assert not "panic" in self.output, "Exited with an error due to a panic"
        self.assert_output_contains(text)

    def assert_no_error(self, text=None):
        """
        Assert the calicoctl command did not exit with an error code.
        Args:
            text:   (optional) Expected text in the command output.
        """
        assert not self.error, "Expected no error running command; \n" \
            "command=" + self.command + "\noutput=" + self.output

        # If text is supplied, assert it appears in the output
        if text:
            self.assert_output_contains(text)

    def assert_output_equals(self, text):
        """
        Assert the calicoctl command output is exactly the supplied text.
        Args:
            text:   Expected text in the command output.
        """
        if not text:
            return
        assert text == self.output, "Expected output to exactly match; \n" + \
                                    "command=" + self.command + "\noutput=\n" + self.output + \
                                    "\nexpected=\n" + text

    def assert_output_equals_ignore_res_version(self, text):
        """
        Assert the calicoctl command output is exactly the supplied text.
        Args:
            text:   Expected text in the command output.
        """
        if not text:
            return

        text = re.sub('resourceVersion: ".*?"', 'resourceVersion: "<ignored>"', text)
        out = re.sub('resourceVersion: ".*?"', 'resourceVersion: "<ignored>"', self.output)

        assert text == out, "Expected output to match after ignoring resource version; \n" + \
                                    "command=" + self.command + "\noutput=\n" + out + \
                                    "\nexpected=\n" + text

    def assert_output_contains(self, text):
        """
        Assert the calicoctl command output contains the supplied text.
        Args:
            text:   Expected text in the command output.
        """
        if not text:
            return
        assert text in self.output, "Expected text in output; \n" + \
            "command=" + self.command + "\noutput=\n" + self.output + \
            "\nexpected=\n" + text

    def assert_output_not_contains(self, text):
        """
        Assert the calicoctl command output does not contain the supplied text.
        Args:
            text:   Expected text in the command output.
        """
        if not text:
            return
        assert not text in self.output, "Unexpected text in output; \n" + \
            "command=" + self.command + "\noutput=\n" + self.output + \
            "\nunexpected=\n" + text


def calicoctl(command, data=None, load_as_stdin=False, format="yaml", only_stdout=False, no_config=False, kdd=False, allowVersionMismatch=True):
    """
    Convenience function for abstracting away calling the calicoctl
    command.

    :param command:  The calicoctl command line parms as a single string.
    :param data:  Input data either as a string or a JSON serializable Python
    object.
    :param load_as_stdin:  Load the input data through stdin rather than by
    loading from file.
    :param format:  Specify the format for loading the data.
    :param only_stdout: Return only the stdout
    :return: The output from the command with leading and trailing
    whitespace removed.
    """
    # If input data is specified, save it to file in the required format.
    if isinstance(data, str):
        data, _ = decode_json_yaml(data)
        assert data is not None, "String data did not decode"
    if data is not None:
        if format == "yaml":
            writeyaml("/tmp/input-data", data)
        else:
            writejson("/tmp/input-data", data)

    stdin = ''
    option_file = ''

    if data and load_as_stdin:
        stdin = 'cat /tmp/input-data | '
        option_file = ' -f -'
    elif data and not load_as_stdin:
        option_file = ' -f /tmp/input-data'

    calicoctl_bin = os.environ.get("CALICOCTL", "/code/bin/calicoctl-linux-amd64")

    if allowVersionMismatch:
        calicoctl_bin += " --allow-version-mismatch"

    if ETCD_SCHEME == "https":
        etcd_auth = "%s:2379" % ETCD_HOSTNAME_SSL
    else:
        etcd_auth = "%s:2379" % get_ip()

    # Export the environment, in case the command has multiple parts, e.g.
    # use of | or ;
    #
    # Pass in all etcd params, the values will be empty if not set anyway
    calicoctl_env_cmd = "export ETCD_ENDPOINTS=%s; " \
                "export ETCD_CA_CERT_FILE=%s; " \
                "export ETCD_CERT_FILE=%s; " \
                "export ETCD_KEY_FILE=%s; " \
                "export DATASTORE_TYPE=%s; %s %s" % \
                (ETCD_SCHEME+"://"+etcd_auth, ETCD_CA, ETCD_CERT, ETCD_KEY,
                 "etcdv3", stdin, calicoctl_bin)
    if kdd:
        calicoctl_env_cmd = "export DATASTORE_TYPE=kubernetes; " \
                "export KUBECONFIG=%s; %s %s" % \
                (KUBECONFIG, stdin, calicoctl_bin)
    if no_config :
        calicoctl_env_cmd = calicoctl_bin
    full_cmd = calicoctl_env_cmd + " " + command + option_file

    try:
        output = log_and_run(full_cmd, stderr=(None if only_stdout else STDOUT))
        return CalicoctlOutput(full_cmd, output)
    except CalledProcessError as e:
        return CalicoctlOutput(full_cmd, e.output, error=e.returncode)


def clean_calico_data(data, extra_keys_to_remove=None):
    """
    Clean the data returned from a calicoctl get command to remove empty
    structs, null values and non-configurable fields.  This makes comparison
    with the input data much simpler.

    Args:
        data: The data to clean.
        extra_keys_to_remove: more keys to remove if needed.

    Returns: The cleaned data.

    """
    new = copy.deepcopy(data)

    # Recursively delete empty structs / nil values and non-configurable
    # fields.
    def clean_elem(elem, extra_keys):
        if isinstance(elem, list):
            # Loop through each element in the list
            for i in elem:
                clean_elem(i, extra_keys)
        if isinstance(elem, dict):
            # Remove non-settable fields, and recursively clean each value of
            # the dictionary, removing nil values or values that are empty
            # dicts after cleaning.
            del_keys = ['creationTimestamp', 'resourceVersion', 'uid']
            if extra_keys is not None:
                for extra_key in extra_keys:
                    del_keys.append(extra_key)
            for k, v in elem.iteritems():
                clean_elem(v, extra_keys)
                if v is None or v == {}:
                    del_keys.append(k)
            for k in del_keys:
                if k in elem:
                    del(elem[k])
    clean_elem(new, extra_keys_to_remove)
    return new


def decode_json_yaml(value):
    try:
        decoded = json.loads(value)
        # fix the python datetime back into isoformat with empty timezone information
        decoded = find_and_format_creation_timestamp(decoded)
        return decoded, "json"
    except ValueError:
        pass
    try:
        decoded = yaml.safe_load(value)
        # fix the python datetime back into isoformat with empty timezone information
        decoded = find_and_format_creation_timestamp(decoded)
        return decoded, "yaml"
    except yaml.YAMLError:
        pass
    return None, None

def find_and_format_creation_timestamp(decoded):
    if decoded:
        if 'items' in decoded:
            for i in xrange(len(decoded['items'])):
                decoded['items'][i] = format_creation_timestamp(decoded['items'][i])
        else:
            decoded = format_creation_timestamp(decoded)
    return decoded

def format_creation_timestamp(decoded):
    if isinstance(decoded, dict) and 'metadata' in decoded and 'creationTimestamp' in decoded['metadata']:
        if isinstance(decoded['metadata']['creationTimestamp'], datetime):
            decoded['metadata']['creationTimestamp'] = decoded.get('metadata', {}). \
                    get('creationTimestamp', datetime.utcnow()).isoformat() + 'Z'
    return decoded

def writeyaml(filename, data):
    """
    Converts a python dict to yaml and outputs to a file.
    :param filename: filename to write
    :param data: dictionary to write out as yaml
    """
    with open(filename, 'w') as f:
        text = yaml.dump(data, default_flow_style=False)
        logger.debug("Writing %s: \n%s" % (filename, truncate_for_log(text, 4000)))
        f.write(text)


def writejson(filename, data):
    """
    Converts a python dict to json and outputs to a file.
    :param filename: filename to write
    :param data: dictionary to write out as json
    """
    with open(filename, 'w') as f:
        text = json.dumps(data,
                          sort_keys=True,
                          indent=2,
                          separators=(',', ': '))
        logger.debug("Writing %s: \n%s" % (filename, truncate_for_log(text, 4000)))
        f.write(text)


def truncate_for_log(text, length):
    if len(text) <=length:
        return text
    return text[:length] + "... <truncated>"


def get_ip(v6=False):
    """
    Return a string of the IP of the hosts interface.
    Try to get the local IP from the environment variables.  This allows
    testers to specify the IP address in cases where there is more than one
    configured IP address for the test system.
    """
    env = LOCAL_IPv6_ENV if v6 else LOCAL_IP_ENV
    ip = os.environ.get(env)
    if not ip:
        logger.debug("%s not set; try to auto detect IP.", env)
        socket_type = socket.AF_INET6 if v6 else socket.AF_INET
        s = socket.socket(socket_type, socket.SOCK_DGRAM)
        remote_ip = "2001:4860:4860::8888" if v6 else "8.8.8.8"
        s.connect((remote_ip, 0))
        ip = s.getsockname()[0]
        s.close()
    else:
        logger.debug("Got local IP from %s=%s", env, ip)

    return ip


# Some of the commands we execute like to mess with the TTY configuration,
# which can break the output formatting. As a wrokaround, save off the
# terminal settings and restore them after each command.
_term_settings = termios.tcgetattr(sys.stdin.fileno())


def log_and_run(command, raise_exception_on_failure=True, stderr=STDOUT):
    def log_output(results):
        if results is None:
            logger.info("  # <no output>")

        lines = results.split("\n")
        for line in lines:
            logger.info("  # %s", line.rstrip())

    try:
        logger.info("%s", command)
        try:
            results = check_output(command, shell=True, stderr=stderr).rstrip()
        finally:
            # Restore terminal settings in case the command we ran manipulated
            # them. Note: under concurrent access, this is still not a perfect
            # solution since another thread's child process may break the
            # settings again before we log below.
            termios.tcsetattr(sys.stdin.fileno(), termios.TCSADRAIN, _term_settings)
        log_output(results)
        return results
    except CalledProcessError as e:
        # Wrap the original exception with one that gives a better error
        # message (including command output).
        logger.info("  # Return code: %s", e.returncode)
        log_output(e.output)
        if raise_exception_on_failure:
            raise e


def curl_etcd(path, options=None, recursive=True, ip=None):
    """
    Perform a curl to etcd, returning JSON decoded response.
    :param path:  The key path to query
    :param options:  Additional options to include in the curl
    :param recursive:  Whether we want recursive query or not
    :return:  The JSON decoded response.
    """
    if options is None:
        options = []
    if ETCD_SCHEME == "https":
        # Etcd is running with SSL/TLS, require key/certificates
        rc = check_output(
            "curl --cacert %s --cert %s --key %s "
            "-sL https://%s:2379/v2/keys/%s?recursive=%s %s"
            % (ETCD_CA, ETCD_CERT, ETCD_KEY, ETCD_HOSTNAME_SSL,
               path, str(recursive).lower(), " ".join(options)),
            shell=True)
    else:
        rc = check_output(
            "curl -sL http://%s:2379/v2/keys/%s?recursive=%s %s"
            % (ip, path, str(recursive).lower(), " ".join(options)),
            shell=True)

    logger.info("etcd RC: %s" % rc.strip())
    return json.loads(rc.strip())

def wipe_etcd(ip):
    # Delete /calico if it exists. This ensures each test has an empty data
    # store at start of day.
    curl_etcd("calico", options=["-XDELETE"], ip=ip)

    # Disable Usage Reporting to usage.projectcalico.org
    # We want to avoid polluting analytics data with unit test noise
    curl_etcd("calico/v1/config/UsageReportingEnabled",
                   options=["-XPUT -d value=False"], ip=ip)

    etcd_container_name = "calico-etcd"
    tls_vars = ""
    if ETCD_SCHEME == "https":
        # Etcd is running with SSL/TLS, require key/certificates
        etcd_container_name = "calico-etcd-ssl"
        tls_vars = ("ETCDCTL_CACERT=/etc/calico/certs/ca.pem " +
                    "ETCDCTL_CERT=/etc/calico/certs/client.pem " +
                    "ETCDCTL_KEY=/etc/calico/certs/client-key.pem ")

    check_output("docker exec " + etcd_container_name + " sh -c '" + tls_vars +
                 "ETCDCTL_API=3 etcdctl del --prefix /calico" +
                 "'", shell=True)

def make_list(kind, items):
    """
    Convert the list of resources into a single List resource type.
    Args:
        items: A list of the resources in the List object.

    Returns:
        None
    """
    assert isinstance(items, list)
    if "List" not in kind:
        kind = kind + "List"
    return {
        'kind': kind,
        'apiVersion': API_VERSION,
        'items': items,
    }

def name(data):
    """
    Returns the name of the resource in the supplied data
    Args:
        data: A dictionary containing the resource.

    Returns: The resource name.
    """
    return data['metadata']['name']

def namespace(data):
    """
    Returns the namespace of the resource in the supplied data
    Args:
       data: A dictionary containing the resource.

    Returns: The resource name.
    """
    return data['metadata']['namespace']

def set_cluster_version(calico_version="", kdd=False):
    """
    Set Calico version in ClusterInformation using the calico_version_helper go app.
    Args:
        calico_version: string with version to set
        kdd: optional bool to indicate use of kubernetes datastore (default False)

    Returns: The command output
    """

    if ETCD_SCHEME == "https":
        etcd_auth = "%s:2379" % ETCD_HOSTNAME_SSL
    else:
        etcd_auth = "%s:2379" % get_ip()

    calico_helper_bin = "/code/tests/fv/helper/bin/calico_version_helper"
    full_cmd = "export ETCD_ENDPOINTS=%s; " \
        "export ETCD_CA_CERT_FILE=%s; " \
        "export ETCD_CERT_FILE=%s; " \
        "export ETCD_KEY_FILE=%s; " \
        "export DATASTORE_TYPE=%s; %s" % \
        (ETCD_SCHEME+"://"+etcd_auth, ETCD_CA, ETCD_CERT, ETCD_KEY,
         "etcdv3", calico_helper_bin)
    if kdd:
        full_cmd = "export DATASTORE_TYPE=kubernetes; " \
            "export KUBECONFIG=%s; %s" % \
            (KUBECONFIG, calico_helper_bin)
    if calico_version:
        full_cmd += " -v " + calico_version

    try:
        output = log_and_run(full_cmd, stderr=STDOUT)
        return CalicoctlOutput(full_cmd, output)
    except CalledProcessError as e:
        return CalicoctlOutput(full_cmd, e.output, error=e.returncode)
