#!/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


DOCUMENTATION = """
module: nxos_devicealias
short_description: Configuration of device alias for Cisco NXOS MDS Switches.
description:
- Configuration of device alias for Cisco MDS NXOS.
version_added: 1.0.0
author:
- Suhas Bharadwaj (@srbharadwaj) (subharad@cisco.com)
notes:
- Tested against Cisco MDS NX-OS 8.4(1)
options:
  distribute:
    description:
    - Enable/Disable device-alias distribution
    type: bool
  mode:
    description:
    - Mode of devices-alias, basic or enhanced
    choices:
    - basic
    - enhanced
    type: str
  da:
    description:
    - List of device-alias to be added or removed
    type: list
    elements: dict
    suboptions:
      name:
        description:
        - Name of the device-alias to be added or removed
        required: true
        type: str
      pwwn:
        description:
        - pwwn to which the name needs to be associated with
        type: str
      remove:
        description:
        - Removes the device-alias if set to True
        type: bool
        default: false
  rename:
    description:
    - List of device-alias to be renamed
    type: list
    elements: dict
    suboptions:
      old_name:
        description:
        - Old name of the device-alias that needs to be renamed
        required: true
        type: str
      new_name:
        description:
        - New name of the device-alias
        required: true
        type: str
"""

EXAMPLES = """
- name: Test that device alias module works
  cisco.nxos.nxos_devicealias:
    da:
    - name: test1_add
      pwwn: 56:2:22:11:22:88:11:67
    - name: test2_add
      pwwn: 65:22:22:11:22:22:11:d
    - name: dev1
      remove: true
    - name: dev2
      remove: true
    distribute: true
    mode: enhanced
    rename:
    - new_name: bcd
      old_name: abc
    - new_name: bcd1
      old_name: abc1


"""

RETURN = """
commands:
  description: commands sent to the device
  returned: always
  type: list
  sample:
    - terminal dont-ask
    - device-alias database
    - device-alias name somename pwwn 10:00:00:00:89:a1:01:03
    - device-alias name somename1 pwwn 10:00:00:00:89:a1:02:03
    - device-alias commit
    - no terminal dont-ask
"""

import string

from ansible.module_utils.basic import AnsibleModule

from ansible_collections.cisco.nxos.plugins.module_utils.network.nxos.nxos import (
    load_config,
    run_commands,
)


__metaclass__ = type

VALID_DA_CHARS = ("-", "_", "$", "^")


class showDeviceAliasStatus(object):
    """docstring for showDeviceAliasStatus"""

    def __init__(self, module):
        self.module = module
        self.distribute = ""
        self.mode = ""
        self.locked = False
        self.update()

    def execute_show_cmd(self, cmd):
        output = execute_show_command(cmd, self.module)[0]
        return output

    def update(self):
        command = "show device-alias status"
        output = self.execute_show_cmd(command).split("\n")
        for o in output:
            if "Fabric Distribution" in o:
                self.distribute = o.split(":")[1].strip().lower()
            if "Mode" in o:
                self.mode = o.split("Mode:")[1].strip().lower()
            if "Locked" in o:
                self.locked = True

    def isLocked(self):
        return self.locked

    def getDistribute(self):
        return self.distribute

    def getMode(self):
        return self.mode


class showDeviceAliasDatabase(object):
    """docstring for showDeviceAliasDatabase"""

    def __init__(self, module):
        self.module = module
        self.da_dict = {}
        self.update()

    def execute_show_cmd(self, cmd):
        output = execute_show_command(cmd, self.module)[0]
        return output

    def update(self):
        command = "show device-alias database"
        # output = execute_show_command(command, self.module)[0].split("\n")
        output = self.execute_show_cmd(command)
        self.da_list = output.split("\n")
        for eachline in self.da_list:
            if "device-alias" in eachline:
                sv = eachline.strip().split()
                self.da_dict[sv[2]] = sv[4]

    def isNameInDaDatabase(self, name):
        return name in self.da_dict.keys()

    def isPwwnInDaDatabase(self, pwwn):
        newpwwn = ":".join(["0" + str(ep) if len(ep) == 1 else ep for ep in pwwn.split(":")])
        return newpwwn in self.da_dict.values()

    def isNamePwwnPresentInDatabase(self, name, pwwn):
        newpwwn = ":".join(["0" + str(ep) if len(ep) == 1 else ep for ep in pwwn.split(":")])
        if name in self.da_dict.keys():
            if newpwwn == self.da_dict[name]:
                return True
        return False

    def getPwwnByName(self, name):
        if name in self.da_dict.keys():
            return self.da_dict[name]
        else:
            return None

    def getNameByPwwn(self, pwwn):
        newpwwn = ":".join(["0" + str(ep) if len(ep) == 1 else ep for ep in pwwn.split(":")])
        for n, p in self.da_dict.items():
            if p == newpwwn:
                return n
        return None


def isPwwnValid(pwwn):
    pwwnsplit = pwwn.split(":")
    if len(pwwnsplit) != 8:
        return False
    for eachpwwnsplit in pwwnsplit:
        if len(eachpwwnsplit) > 2 or len(eachpwwnsplit) < 1:
            return False
        if not all(c in string.hexdigits for c in eachpwwnsplit):
            return False
    return True


def isNameValid(name):
    if not name[0].isalpha():
        # Illegal first character. Name must start with a letter
        return False
    if len(name) > 64:
        return False
    for character in name:
        if not character.isalnum() and character not in VALID_DA_CHARS:
            return False
    return True


def execute_show_command(command, module, command_type="cli_show"):
    output = "text"
    commands = [{"command": command, "output": output}]
    out = run_commands(module, commands)
    return out


def flatten_list(command_lists):
    flat_command_list = []
    for command in command_lists:
        if isinstance(command, list):
            flat_command_list.extend(command)
        else:
            flat_command_list.append(command)
    return flat_command_list


def main():
    element_spec = dict(
        name=dict(required=True, type="str"),
        pwwn=dict(type="str"),
        remove=dict(type="bool", default=False),
    )

    element_spec_rename = dict(
        old_name=dict(required=True, type="str"),
        new_name=dict(required=True, type="str"),
    )

    argument_spec = dict(
        distribute=dict(type="bool"),
        mode=dict(type="str", choices=["enhanced", "basic"]),
        da=dict(type="list", elements="dict", options=element_spec),
        rename=dict(type="list", elements="dict", options=element_spec_rename),
    )

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

    warnings = list()
    messages = list()
    commands_to_execute = list()
    result = {"changed": False}

    distribute = module.params["distribute"]
    mode = module.params["mode"]
    da = module.params["da"]
    rename = module.params["rename"]

    # Step 0.0: Validate syntax of name and pwwn
    #       Also validate syntax of rename arguments
    if da is not None:
        for eachdict in da:
            name = eachdict["name"]
            pwwn = eachdict["pwwn"]
            remove = eachdict["remove"]
            if pwwn is not None:
                pwwn = pwwn.lower()
            if not remove:
                if pwwn is None:
                    module.fail_json(
                        msg="This device alias name "
                        + str(name)
                        + " which needs to be added, does not have pwwn specified. Please specify a valid pwwn",
                    )
                if not isNameValid(name):
                    module.fail_json(
                        msg="This pwwn name is invalid : "
                        + str(name)
                        + ". Note that name cannot be more than 64 alphanumeric chars, "
                        + "it must start with a letter, and can only contain these characters: "
                        + ", ".join(["'{0}'".format(c) for c in VALID_DA_CHARS]),
                    )
                if not isPwwnValid(pwwn):
                    module.fail_json(
                        msg="This pwwn is invalid : "
                        + str(pwwn)
                        + ". Please check that its a valid pwwn",
                    )
    if rename is not None:
        for eachdict in rename:
            oldname = eachdict["old_name"]
            newname = eachdict["new_name"]
            if not isNameValid(oldname):
                module.fail_json(
                    msg="This pwwn name is invalid : "
                    + str(oldname)
                    + ". Note that name cannot be more than 64 alphanumeric chars, "
                    + "it must start with a letter, and can only contain these characters: "
                    + ", ".join(["'{0}'".format(c) for c in VALID_DA_CHARS]),
                )
            if not isNameValid(newname):
                module.fail_json(
                    msg="This pwwn name is invalid : "
                    + str(newname)
                    + ". Note that name cannot be more than 64 alphanumeric chars, "
                    + "it must start with a letter, and can only contain these characters: "
                    + ", ".join(["'{0}'".format(c) for c in VALID_DA_CHARS]),
                )

    # Step 0.1: Check DA status
    shDAStausObj = showDeviceAliasStatus(module)
    d = shDAStausObj.getDistribute()
    m = shDAStausObj.getMode()
    if shDAStausObj.isLocked():
        module.fail_json(msg="device-alias has acquired lock on the switch. Hence cannot procced.")

    # Step 1: Process distribute
    commands = []
    if distribute is not None:
        if distribute:
            # playbook has distribute as True(enabled)
            if d == "disabled":
                # but switch distribute is disabled(false), so set it to
                # true(enabled)
                commands.append("device-alias distribute")
                messages.append("device-alias distribute changed from disabled to enabled")
            else:
                messages.append(
                    "device-alias distribute remains unchanged. current distribution mode is enabled",
                )
        else:
            # playbook has distribute as False(disabled)
            if d == "enabled":
                # but switch distribute is enabled(true), so set it to
                # false(disabled)
                commands.append("no device-alias distribute")
                messages.append("device-alias distribute changed from enabled to disabled")
            else:
                messages.append(
                    "device-alias distribute remains unchanged. current distribution mode is disabled",
                )

    cmds = flatten_list(commands)
    if cmds:
        commands_to_execute = commands_to_execute + cmds
        if module.check_mode:
            # Check mode implemented at the da_add/da_remove stage
            pass
        else:
            result["changed"] = True
            load_config(module, cmds)

    # Step 2: Process mode
    commands = []
    if mode is not None:
        if mode == "basic":
            # playbook has mode as basic
            if m == "enhanced":
                # but switch mode is enhanced, so set it to basic
                commands.append("no device-alias mode enhanced")
                messages.append("device-alias mode changed from enhanced to basic")
            else:
                messages.append("device-alias mode remains unchanged. current mode is basic")

        else:
            # playbook has mode as enhanced
            if m == "basic":
                # but switch mode is basic, so set it to enhanced
                commands.append("device-alias mode enhanced")
                messages.append("device-alias mode changed from basic to enhanced")
            else:
                messages.append("device-alias mode remains unchanged. current mode is enhanced")

    if commands:
        if distribute:
            commands.append("device-alias commit")
            commands = ["terminal dont-ask"] + commands + ["no terminal dont-ask"]
        else:
            if distribute is None and d == "enabled":
                commands.append("device-alias commit")
                commands = ["terminal dont-ask"] + commands + ["no terminal dont-ask"]

    cmds = flatten_list(commands)

    if cmds:
        commands_to_execute = commands_to_execute + cmds
        if module.check_mode:
            # Check mode implemented at the end
            pass
        else:
            result["changed"] = True
            load_config(module, cmds)

    # Step 3: Process da
    commands = []
    shDADatabaseObj = showDeviceAliasDatabase(module)
    if da is not None:
        da_remove_list = []
        da_add_list = []
        for eachdict in da:
            name = eachdict["name"]
            pwwn = eachdict["pwwn"]
            remove = eachdict["remove"]
            if pwwn is not None:
                pwwn = pwwn.lower()
            if remove:
                if shDADatabaseObj.isNameInDaDatabase(name):
                    commands.append("no device-alias name " + name)
                    da_remove_list.append(name)
                else:
                    messages.append(
                        name
                        + " - This device alias name is not in switch device-alias database, hence cannot be removed.",
                    )
            else:
                if shDADatabaseObj.isNamePwwnPresentInDatabase(name, pwwn):
                    messages.append(
                        name
                        + " : "
                        + pwwn
                        + " - This device alias name,pwwn is already in switch device-alias database, hence nothing to configure",
                    )
                else:
                    if shDADatabaseObj.isNameInDaDatabase(name):
                        module.fail_json(
                            msg=name
                            + " - This device alias name is already present in switch device-alias database but assigned to another pwwn ("
                            + shDADatabaseObj.getPwwnByName(name)
                            + ") hence cannot be added",
                        )

                    elif shDADatabaseObj.isPwwnInDaDatabase(pwwn):
                        module.fail_json(
                            msg=pwwn
                            + " - This device alias pwwn is already present in switch device-alias database but assigned to another name ("
                            + shDADatabaseObj.getNameByPwwn(pwwn)
                            + ") hence cannot be added",
                        )

                    else:
                        commands.append("device-alias name " + name + " pwwn " + pwwn)
                        da_add_list.append(name)

        if len(da_add_list) != 0 or len(da_remove_list) != 0:
            commands = ["device-alias database"] + commands
            if distribute:
                commands.append("device-alias commit")
                commands = ["terminal dont-ask"] + commands + ["no terminal dont-ask"]
            else:
                if distribute is None and d == "enabled":
                    commands.append("device-alias commit")
                    commands = ["terminal dont-ask"] + commands + ["no terminal dont-ask"]

        cmds = flatten_list(commands)
        if cmds:
            commands_to_execute = commands_to_execute + cmds
            if module.check_mode:
                # Check mode implemented at the end
                pass
            else:
                result["changed"] = True
                load_config(module, cmds)
                if len(da_remove_list) != 0:
                    messages.append(
                        "the required device-alias were removed. " + ",".join(da_remove_list),
                    )
                if len(da_add_list) != 0:
                    messages.append(
                        "the required device-alias were added. " + ",".join(da_add_list),
                    )

    # Step 5: Process rename
    commands = []
    if rename is not None:
        for eachdict in rename:
            oldname = eachdict["old_name"]
            newname = eachdict["new_name"]
            if shDADatabaseObj.isNameInDaDatabase(newname):
                module.fail_json(
                    changed=False,
                    commands=cmds,
                    msg=newname
                    + " - this name is already present in the device-alias database, hence we cannot rename "
                    + oldname
                    + " with this one",
                )
            if shDADatabaseObj.isNameInDaDatabase(oldname):
                commands.append("device-alias rename " + oldname + " " + newname)
            else:
                module.fail_json(
                    changed=False,
                    commands=cmds,
                    msg=oldname
                    + " - this name is not present in the device-alias database, hence we cannot rename.",
                )

        if len(commands) != 0:
            commands = ["device-alias database"] + commands
            if distribute:
                commands.append("device-alias commit")
                commands = ["terminal dont-ask"] + commands + ["no terminal dont-ask"]
            else:
                if distribute is None and d == "enabled":
                    commands.append("device-alias commit")
                    commands = ["terminal dont-ask"] + commands + ["no terminal dont-ask"]
        cmds = flatten_list(commands)
        if cmds:
            commands_to_execute = commands_to_execute + cmds
            if module.check_mode:
                # Check mode implemented at the end
                pass
            else:
                result["changed"] = True
                load_config(module, cmds)

    # Step END: check for 'check' mode
    if module.check_mode:
        module.exit_json(
            changed=False,
            commands=commands_to_execute,
            msg="Check Mode: No cmds issued to the hosts",
        )

    result["messages"] = messages
    result["commands"] = commands_to_execute
    result["warnings"] = warnings
    module.exit_json(**result)


if __name__ == "__main__":
    main()