#!/usr/bin/python
#
# Copyright: Ansible Project
# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)

from __future__ import absolute_import, division, print_function


__metaclass__ = type


DOCUMENTATION = """
module: iosxr_config
author: Ricardo Carrillo Cruz (@rcarrillocruz)
short_description: Module to manage configuration sections.
description:
- Cisco IOS XR configurations use a simple block indent file syntax for segmenting
  configuration into sections.  This module provides an implementation for working
  with IOS XR configuration sections in a deterministic way.
version_added: 1.0.0
extends_documentation_fragment:
- cisco.iosxr.iosxr
notes:
- This module works with connection C(network_cli). See L(the IOS-XR Platform Options,../network/user_guide/platform_iosxr.html).
- This module does not support C(netconf) connection
- Abbreviated commands are NOT idempotent, see L(Network FAQ,../network/user_guide/faq.html
  #why-do-the-config-modules-always-return-changed-true-with-abbreviated-commands).
- Avoid service disrupting changes (viz. Management IP) from config replace.
- Do not use C(end) in the replace config file.
- To ensure idempotency and correct diff the configuration lines in the relevant module options should be similar to how they
  appear if present in the running configuration on device including the indentation.
options:
  lines:
    description:
    - The ordered set of commands that should be configured in the section. The commands
      must be the exact same commands as found in the device running-config as found in the
      device running-config to ensure idempotency and correct diff. Be sure to note the
      configuration command syntax as some commands are automatically modified by the
      device config parser.
    type: list
    elements: str
    aliases:
    - commands
  parents:
    description:
    - The ordered set of parents that uniquely identify the section or hierarchy the
      commands should be checked against.  If the parents argument is omitted, the
      commands are checked against the set of top level or global commands.
    type: list
    elements: str
  src:
    description:
    - Specifies the source path to the file that contains the configuration or configuration
      template to load. The path to the source file can either be the full path on
      the Ansible control host or a relative path from the playbook or role root directory.  This
      argument is mutually exclusive with I(lines), I(parents). The configuration lines in the
      source file should be similar to how it will appear if present in the running-configuration
      of the device to ensure idempotency and correct diff.
    type: path
  before:
    description:
    - The ordered set of commands to push on to the command stack if a change needs
      to be made.  This allows the playbook designer the opportunity to perform configuration
      commands prior to pushing any changes without affecting how the set of commands
      are matched against the system.
    type: list
    elements: str
  after:
    description:
    - The ordered set of commands to append to the end of the command stack if a change
      needs to be made.  Just like with I(before) this allows the playbook designer
      to append a set of commands to be executed after the command set.
    type: list
    elements: str
  match:
    description:
    - Instructs the module on the way to perform the matching of the set of commands
      against the current device config.  If match is set to I(line), commands are
      matched line by line.  If match is set to I(strict), command lines are matched
      with respect to position.  If match is set to I(exact), command lines must be
      an equal match.  Finally, if match is set to I(none), the module will not attempt
      to compare the source configuration with the running configuration on the remote
      device.
    type: str
    default: line
    choices:
    - line
    - strict
    - exact
    - none
  replace:
    description:
    - Instructs the module on the way to perform the configuration on the device.  If
      the replace argument is set to I(line) then the modified lines are pushed to
      the device in configuration mode.  If the replace argument is set to I(block)
      then the entire command block is pushed to the device in configuration mode
      if any line is not correct.
    type: str
    default: line
    choices:
    - line
    - block
    - config
  force:
    description:
    - The force argument instructs the module to not consider the current devices
      running-config.  When set to true, this will cause the module to push the contents
      of I(src) into the device without first checking if already configured.
    - Note this argument should be considered deprecated.  To achieve the equivalent,
      set the C(match=none) which is idempotent.  This argument will be removed in
      a future release.
    type: bool
    default: no
  config:
    description:
    - The module, by default, will connect to the remote device and retrieve the current
      running-config to use as a base for comparing against the contents of source.  There
      are times when it is not desirable to have the task get the current running-config
      for every task in a playbook.  The I(config) argument allows the implementer
      to pass in the configuration to use as the base config for comparison.
      The configuration lines for this option should be similar to how it will appear if present
      in the running-configuration of the device to ensure idempotency and correct diff.
    type: str
  backup:
    description:
    - This argument will cause the module to create a full backup of the current C(running-config)
      from the remote device before any changes are made. If the C(backup_options)
      value is not given, the backup file is written to the C(backup) folder in the
      playbook root directory or role root directory, if playbook is part of an ansible
      role. If the directory does not exist, it is created.
    type: bool
    default: no
  comment:
    description:
    - Allows a commit description to be specified to be included when the configuration
      is committed.  If the configuration is not changed or committed, this argument
      is ignored.
    type: str
    default: configured by iosxr_config
  admin:
    description:
    - Enters into administration configuration mode for making config changes to the
      device.
    type: bool
    default: no
  label:
    description:
    - Allows a commit label to be specified to be included when the configuration
      is committed. A valid label must begin with an alphabet and not exceed 30 characters,
      only alphabets, digits, hyphens and underscores are allowed. If the configuration
      is not changed or committed, this argument is ignored.
    type: str
  backup_options:
    description:
    - This is a dict object containing configurable options related to backup file
      path. The value of this option is read only when C(backup) is set to I(yes),
      if C(backup) is set to I(no) this option will be silently ignored.
    suboptions:
      filename:
        description:
        - The filename to be used to store the backup configuration. If the filename
          is not given it will be generated based on the hostname, current time and
          date in format defined by <hostname>_config.<current-date>@<current-time>
        type: str
      dir_path:
        description:
        - This option provides the path ending with directory name in which the backup
          configuration file will be stored. If the directory does not exist it will
          be first created and the filename is either the value of C(filename) or
          default filename as described in C(filename) options description. If the
          path value is not given in that case a I(backup) directory will be created
          in the current working directory and backup configuration will be copied
          in C(filename) within I(backup) directory.
        type: path
    type: dict
  exclusive:
    description:
    - Enters into exclusive configuration mode that locks out all users from committing
      configuration changes until the exclusive session ends.
    type: bool
    default: false
  disable_default_comment:
    description:
    - disable default comment when set to True.
    type: bool
    default: false
"""

EXAMPLES = """
- name: configure top level configuration
  cisco.iosxr.iosxr_config:
    lines: hostname {{ inventory_hostname }}

- name: configure interface settings
  cisco.iosxr.iosxr_config:
    lines:
    - description test interface
    - ip address 172.31.1.1 255.255.255.0
    parents: interface GigabitEthernet0/0/0/0

- name: load a config from disk and replace the current config
  cisco.iosxr.iosxr_config:
    src: config.cfg
    replace: config
    backup: yes

- name: for idempotency, use full-form commands
  cisco.iosxr.iosxr_config:
    lines:
      # - shut
    - shutdown
    # parents: int g0/0/0/1
    parents: interface GigabitEthernet0/0/0/1

- name: configurable backup path
  cisco.iosxr.iosxr_config:
    src: config.cfg
    backup: yes
    backup_options:
      filename: backup.cfg
      dir_path: /home/user
"""

RETURN = """
commands:
  description: The set of commands that will be pushed to the remote device
  returned: If there are commands to run against the host
  type: list
  sample: ['hostname foo', 'router ospf 1', 'router-id 1.1.1.1']
backup_path:
  description: The full path to the backup file
  returned: when backup is yes
  type: str
  sample: /playbooks/ansible/backup/iosxr01_config.2016-07-16@22:28:34
filename:
  description: The name of the backup file
  returned: when backup is yes and filename is not specified in backup options
  type: str
  sample: iosxr01_config.2016-07-16@22:28:34
shortname:
  description: The full path to the backup file excluding the timestamp
  returned: when backup is yes and filename is not specified in backup options
  type: str
  sample: /playbooks/ansible/backup/iosxr01_config
date:
  description: The date extracted from the backup file name
  returned: when backup is yes
  type: str
  sample: "2016-07-16"
time:
  description: The time extracted from the backup file name
  returned: when backup is yes
  type: str
  sample: "22:28:34"
"""
import os
import re
import tempfile

from ansible.module_utils._text import to_bytes, to_text
from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.connection import ConnectionError
from ansible_collections.ansible.netcommon.plugins.module_utils.network.common.config import (
    NetworkConfig,
    dumps,
)

from ansible_collections.cisco.iosxr.plugins.module_utils.network.iosxr.iosxr import (
    copy_file,
    get_config,
    get_connection,
    load_config,
)


DEFAULT_COMMIT_COMMENT = "configured by iosxr_config"


def copy_file_to_node(module):
    """Copy config file to IOS-XR node. We use SFTP because older IOS-XR versions don't handle SCP very well."""
    file = tempfile.NamedTemporaryFile("wb", delete=False)
    src = os.path.realpath(file.name)
    file.write(to_bytes(module.params["src"], errors="surrogate_or_strict"))
    file.close()

    dst = "/harddisk:/ansible_config.txt"
    copy_file(module, src, dst, "sftp")

    os.remove(src)

    return True


def check_args(module, warnings):
    if module.params["comment"]:
        if len(module.params["comment"]) > 60:
            module.fail_json(msg="comment argument cannot be more than 60 characters")
    if module.params["label"]:
        label = module.params["label"]
        if len(label) > 30:
            module.fail_json(msg="label argument cannot be more than 30 characters")
        if not label[0].isalpha():
            module.fail_json(msg="label argument must begin with an alphabet")
        valid_chars = re.match(r"[\w-]*$", label)
        if not valid_chars:
            module.fail_json(
                msg="label argument must only contain alphabets,"
                + "digits, underscores or hyphens",
            )
    if module.params["force"]:
        warnings.append(
            "The force argument is deprecated, please use "
            "match=none instead.  This argument will be "
            "removed in the future",
        )


def get_running_config(module):
    contents = module.params["config"]
    if not contents:
        contents = get_config(module)
    return contents


def get_candidate(module):
    candidate = ""
    if module.params["src"]:
        candidate = module.params["src"]
    elif module.params["lines"]:
        candidate_obj = NetworkConfig(indent=1, comment_tokens=["!"])
        parents = module.params["parents"] or list()
        candidate_obj.add(module.params["lines"], parents=parents)
        candidate = dumps(candidate_obj, "raw")
    return candidate


def run(module, result):
    match = module.params["match"]
    replace = module.params["replace"]
    replace_config = replace == "config"
    path = module.params["parents"]
    comment = module.params["comment"]
    admin = module.params["admin"]
    exclusive = module.params["exclusive"]
    check_mode = module.check_mode
    label = module.params["label"]

    candidate_config = get_candidate(module)
    running_config = get_running_config(module)

    commands = None
    replace_file_path = None
    connection = get_connection(module)
    try:
        response = connection.get_diff(
            candidate=candidate_config,
            running=running_config,
            diff_match=match,
            path=path,
            diff_replace=replace,
        )
    except ConnectionError as exc:
        module.fail_json(msg=to_text(exc, errors="surrogate_then_replace"))

    config_diff = response.get("config_diff")

    if replace_config:
        running_base_diff_resp = connection.get_diff(
            candidate=running_config,
            running=candidate_config,
            diff_match=match,
            path=path,
            diff_replace=replace,
        )
        if config_diff or running_base_diff_resp["config_diff"]:
            ret = copy_file_to_node(module)
            if not ret:
                module.fail_json(msg="Copy of config file to the node failed")

            commands = ["load harddisk:/ansible_config.txt"]
            replace_file_path = "harddisk:/ansible_config.txt"

    if config_diff or commands:
        if not replace_config:
            commands = config_diff.split("\n")

        if any((module.params["lines"], module.params["src"])):
            if module.params["before"]:
                commands[:0] = module.params["before"]

            if module.params["after"]:
                commands.extend(module.params["after"])

            result["commands"] = commands

        commit = not check_mode
        diff = load_config(
            module,
            commands,
            commit=commit,
            replace=replace_file_path,
            comment=comment,
            admin=admin,
            exclusive=exclusive,
            label=label,
        )
        if diff:
            result["diff"] = dict(prepared=diff)

        result["changed"] = True


def main():
    """main entry point for module execution"""
    backup_spec = dict(filename=dict(), dir_path=dict(type="path"))
    argument_spec = dict(
        src=dict(type="path"),
        lines=dict(aliases=["commands"], type="list", elements="str"),
        parents=dict(type="list", elements="str"),
        before=dict(type="list", elements="str"),
        after=dict(type="list", elements="str"),
        match=dict(default="line", choices=["line", "strict", "exact", "none"]),
        replace=dict(default="line", choices=["line", "block", "config"]),
        # this argument is deprecated in favor of setting match: none
        # it will be removed in a future version
        force=dict(default=False, type="bool"),
        config=dict(),
        backup=dict(type="bool", default=False),
        backup_options=dict(type="dict", options=backup_spec),
        comment=dict(default=DEFAULT_COMMIT_COMMENT),
        admin=dict(type="bool", default=False),
        disable_default_comment=dict(type="bool", default=False),
        exclusive=dict(type="bool", default=False),
        label=dict(),
    )

    mutually_exclusive = [("lines", "src"), ("parents", "src")]

    required_if = [
        ("match", "strict", ["lines"]),
        ("match", "exact", ["lines"]),
        ("replace", "block", ["lines"]),
        ("replace", "config", ["src"]),
    ]

    module = AnsibleModule(
        argument_spec=argument_spec,
        mutually_exclusive=mutually_exclusive,
        required_if=required_if,
        supports_check_mode=True,
    )

    if module.params["force"] is True:
        module.params["match"] = "none"
    if (
        module.params["disable_default_comment"] is True
        and module.params["comment"] == DEFAULT_COMMIT_COMMENT
    ):
        module.params["comment"] = None
    warnings = list()

    check_args(module, warnings)

    result = dict(changed=False, warnings=warnings)

    if module.params["backup"]:
        result["__backup__"] = get_config(module)

    if any((module.params["src"], module.params["lines"])):
        run(module, result)

    if result.get("changed") and any((module.params["src"], module.params["lines"])):
        msg = (
            "To ensure idempotency and correct diff the input configuration lines should be"
            " similar to how they appear if present in"
            " the running configuration on device"
        )
        if module.params["src"]:
            msg += " including the indentation"
        if "warnings" in result:
            result["warnings"].append(msg)
        else:
            result["warnings"] = msg

    module.exit_json(**result)


if __name__ == "__main__":
    main()