# --------------------------------------------------------------------------------------------
# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License. See License.txt in the project root for license information.
# --------------------------------------------------------------------------------------------

from __future__ import print_function
import argparse

from azure.cli.core.commands import ExtensionCommandSource
from azure.cli.core.commands.constants import SURVEY_PROMPT

from knack.help import (HelpFile as KnackHelpFile, CommandHelpFile as KnackCommandHelpFile,
                        GroupHelpFile as KnackGroupHelpFile, ArgumentGroupRegistry as KnackArgumentGroupRegistry,
                        HelpExample as KnackHelpExample, HelpParameter as KnackHelpParameter,
                        _print_indent, CLIHelp, HelpAuthoringException)

from knack.log import get_logger
from knack.util import CLIError

logger = get_logger(__name__)

PRIVACY_STATEMENT = """
Welcome to Azure CLI!
---------------------
Use `az -h` to see available commands or go to https://aka.ms/cli.

Telemetry
---------
The Azure CLI collects usage data in order to improve your experience.
The data is anonymous and does not include commandline argument values.
The data is collected by Microsoft.

You can change your telemetry settings with `az configure`.
"""

WELCOME_MESSAGE = r"""
     /\
    /  \    _____   _ _  ___ _
   / /\ \  |_  / | | | \'__/ _\
  / ____ \  / /| |_| | | |  __/
 /_/    \_\/___|\__,_|_|  \___|


Welcome to the cool new Azure CLI!

Use `az --version` to display the current version.
Here are the base commands:
"""


# PrintMixin class to decouple printing functionality from AZCLIHelp class.
# Most of these methods override print methods in CLIHelp
class CLIPrintMixin(CLIHelp):
    def _print_header(self, cli_name, help_file):
        super(CLIPrintMixin, self)._print_header(cli_name, help_file)

        links = help_file.links
        if links:
            link_text = "{} and {}".format(", ".join([link["url"] for link in links[0:-1]]),
                                           links[-1]["url"]) if len(links) > 1 else links[0]["url"]
            link_text = "For more information, see: {}\n".format(link_text)
            _print_indent(link_text, 2, width=self.textwrap_width)

    def _print_detailed_help(self, cli_name, help_file):
        CLIPrintMixin._print_extensions_msg(help_file)
        super(CLIPrintMixin, self)._print_detailed_help(cli_name, help_file)

    @staticmethod
    def _get_choices_defaults_sources_str(p):
        choice_str = u'  Allowed values: {}.'.format(', '.join(sorted([str(x) for x in p.choices]))) \
            if p.choices else ''
        default_str = u'  Default: {}.'.format(p.default) if p.default and p.default != argparse.SUPPRESS else ''
        value_sources_str = CLIPrintMixin._process_value_sources(p) if p.value_sources else ''
        return u'{}{}{}'.format(choice_str, default_str, value_sources_str)

    @staticmethod
    def _print_examples(help_file):
        from colorama import Style
        indent = 0
        _print_indent('Examples', indent)
        for e in AzCliHelp.example_provider(help_file):
            indent = 1
            _print_indent(u'{0}'.format(e.short_summary), indent)
            indent = 2
            if e.long_summary:
                _print_indent(u'{0}'.format(e.long_summary), indent)
            _print_indent(u'{0}'.format(e.command), indent)
            print('')
        indent = 0
        message = 'For more specific examples, use: az find "az {}"'.format(help_file.command)
        _print_indent(Style.BRIGHT + message + Style.RESET_ALL + '\n', indent)

    @staticmethod
    def _process_value_sources(p):
        commands, strings, urls = [], [], []

        for item in p.value_sources:
            if "string" in item:
                strings.append(item["string"])
            elif "link" in item and "command" in item["link"]:
                commands.append(item["link"]["command"])
            elif "link" in item and "url" in item["link"]:
                urls.append(item["link"]["url"])

        command_str = u'  Values from: {}.'.format(", ".join(commands)) if commands else ''
        string_str = u'  {}'.format(", ".join(strings)) if strings else ''
        string_str = string_str + "." if string_str and not string_str.endswith(".") else string_str
        urls_str = u'  For more info, go to: {}.'.format(", ".join(urls)) if urls else ''
        return u'{}{}{}'.format(command_str, string_str, urls_str)

    @staticmethod
    def _print_extensions_msg(help_file):
        if help_file.type != 'command':
            return
        if isinstance(help_file.command_source, ExtensionCommandSource):
            logger.warning(help_file.command_source.get_command_warn_msg())
            if help_file.command_source.preview:
                logger.warning(help_file.command_source.get_preview_warn_msg())


class AzCliHelp(CLIPrintMixin, CLIHelp):

    def __init__(self, cli_ctx):
        super(AzCliHelp, self).__init__(cli_ctx,
                                        privacy_statement=PRIVACY_STATEMENT,
                                        welcome_message=WELCOME_MESSAGE,
                                        command_help_cls=CliCommandHelpFile,
                                        group_help_cls=CliGroupHelpFile,
                                        help_cls=CliHelpFile)
        from knack.help import HelpObject

        # TODO: This workaround is used to avoid a bizarre bug in Python 2.7. It
        # essentially reassigns Knack's HelpObject._normalize_text implementation
        # with an identical implemenation in Az. For whatever reason, this fixes
        # the bug in Python 2.7.
        @staticmethod
        def new_normalize_text(s):
            if not s or len(s) < 2:
                return s or ''
            s = s.strip()
            initial_upper = s[0].upper() + s[1:]
            trailing_period = '' if s[-1] in '.!?' else '.'
            return initial_upper + trailing_period

        HelpObject._normalize_text = new_normalize_text  # pylint: disable=protected-access

        self._register_help_loaders()
        self._name_to_content = {}

    # override
    def show_help(self, cli_name, nouns, parser, is_group):
        self.update_loaders_with_help_file_contents(nouns)
        super(AzCliHelp, self).show_help(cli_name, nouns, parser, is_group)
        print(SURVEY_PROMPT)

    def _register_help_loaders(self):
        import azure.cli.core._help_loaders as help_loaders
        import inspect

        def is_loader_cls(cls):
            return inspect.isclass(cls) and cls.__name__ != 'BaseHelpLoader'and issubclass(cls, help_loaders.BaseHelpLoader)  # pylint: disable=line-too-long

        versioned_loaders = {}
        for cls_name, loader_cls in inspect.getmembers(help_loaders, is_loader_cls):
            loader = loader_cls(self)
            versioned_loaders[cls_name] = loader

        if len(versioned_loaders) != len({ldr.version for ldr in versioned_loaders.values()}):
            ldrs_str = " ".join("{}-version:{}".format(cls_name, ldr.version) for cls_name, ldr in versioned_loaders.items())  # pylint: disable=line-too-long
            raise CLIError("Two loaders have the same version. Loaders:\n\t{}".format(ldrs_str))

        self.versioned_loaders = versioned_loaders

    def update_loaders_with_help_file_contents(self, nouns):
        loader_file_names_dict = {}
        file_name_set = set()
        for ldr_cls_name, loader in self.versioned_loaders.items():
            new_file_names = loader.get_noun_help_file_names(nouns) or []
            loader_file_names_dict[ldr_cls_name] = new_file_names
            file_name_set.update(new_file_names)

        for file_name in file_name_set:
            if file_name not in self._name_to_content:
                with open(file_name, 'r') as f:
                    self._name_to_content[file_name] = f.read()

        for ldr_cls_name, file_names in loader_file_names_dict.items():
            file_contents = {}
            for name in file_names:
                file_contents[name] = self._name_to_content[name]
            self.versioned_loaders[ldr_cls_name].update_file_contents(file_contents)

    # This method is meant to be a hook that can be overridden by an extension or module.
    @staticmethod
    def example_provider(help_file):
        return help_file.examples


class CliHelpFile(KnackHelpFile):

    def __init__(self, help_ctx, delimiters):
        # Each help file (for a command or group) has a version denoting the source of its data.
        super(CliHelpFile, self).__init__(help_ctx, delimiters)
        self.links = []

    def _should_include_example(self, ex):
        supported_profiles = ex.get('supported-profiles')
        unsupported_profiles = ex.get('unsupported-profiles')

        if all((supported_profiles, unsupported_profiles)):
            raise HelpAuthoringException("An example cannot have both supported-profiles and unsupported-profiles.")

        if supported_profiles:
            supported_profiles = [profile.strip() for profile in supported_profiles.split(',')]
            return self.help_ctx.cli_ctx.cloud.profile in supported_profiles

        if unsupported_profiles:
            unsupported_profiles = [profile.strip() for profile in unsupported_profiles.split(',')]
            return self.help_ctx.cli_ctx.cloud.profile not in unsupported_profiles

        return True

    # Needs to override base implementation to exclude unsupported examples.
    def _load_from_data(self, data):
        if not data:
            return

        if isinstance(data, str):
            self.long_summary = data
            return

        if 'type' in data:
            self.type = data['type']

        if 'short-summary' in data:
            self.short_summary = data['short-summary']

        self.long_summary = data.get('long-summary')

        if 'examples' in data:
            self.examples = []
            for d in data['examples']:
                if self._should_include_example(d):
                    self.examples.append(HelpExample(**d))

    def load(self, options):
        ordered_loaders = sorted(self.help_ctx.versioned_loaders.values(), key=lambda ldr: ldr.version)
        for loader in ordered_loaders:
            loader.versioned_load(self, options)


class CliGroupHelpFile(KnackGroupHelpFile, CliHelpFile):

    def load(self, options):
        # forces class to use this load method even if KnackGroupHelpFile overrides CliHelpFile's method.
        CliHelpFile.load(self, options)


class CliCommandHelpFile(KnackCommandHelpFile, CliHelpFile):

    def __init__(self, help_ctx, delimiters, parser):
        super(CliCommandHelpFile, self).__init__(help_ctx, delimiters, parser)
        self.type = 'command'
        self.command_source = getattr(parser, 'command_source', None)

        self.parameters = []

        for action in [a for a in parser._actions if a.help != argparse.SUPPRESS]:  # pylint: disable=protected-access
            if action.option_strings:
                self._add_parameter_help(action)
            else:
                # use metavar for positional parameters
                param_kwargs = {
                    'name_source': [action.metavar or action.dest],
                    'deprecate_info': getattr(action, 'deprecate_info', None),
                    'preview_info': getattr(action, 'preview_info', None),
                    'description': action.help,
                    'choices': action.choices,
                    'required': False,
                    'default': None,
                    'group_name': 'Positional'
                }
                self.parameters.append(HelpParameter(**param_kwargs))

        help_param = next(p for p in self.parameters if p.name == '--help -h')
        help_param.group_name = 'Global Arguments'

        # update parameter type so we can use overriden update_from_data method to update value sources.
        for param in self.parameters:
            param.__class__ = HelpParameter

    def _load_from_data(self, data):
        super(CliCommandHelpFile, self)._load_from_data(data)

        if isinstance(data, str) or not self.parameters or not data.get('parameters'):
            return

        loaded_params = []
        loaded_param = {}
        for param in self.parameters:
            loaded_param = next((n for n in data['parameters'] if n['name'] == param.name), None)
            if loaded_param:
                param.update_from_data(loaded_param)
            loaded_params.append(param)

        self.parameters = loaded_params

    def load(self, options):
        # forces class to use this load method even if KnackCommandHelpFile overrides CliHelpFile's method.
        CliHelpFile.load(self, options)


class ArgumentGroupRegistry(KnackArgumentGroupRegistry):  # pylint: disable=too-few-public-methods

    def __init__(self, group_list):

        super(ArgumentGroupRegistry, self).__init__(group_list)
        self.priorities = {
            None: 0,
            'Resource Id Arguments': 1,
            'Generic Update Arguments': 998,
            'Global Arguments': 1000,
        }
        priority = 2
        # any groups not already in the static dictionary should be prioritized alphabetically
        other_groups = [g for g in sorted(list(set(group_list))) if g not in self.priorities]
        for group in other_groups:
            self.priorities[group] = priority
            priority += 1


class HelpExample(KnackHelpExample):  # pylint: disable=too-few-public-methods

    def __init__(self, **_data):
        # Old attributes
        _data['name'] = _data.get('name', '')
        _data['text'] = _data.get('text', '')
        super(HelpExample, self).__init__(_data)

        self.name = _data.get('summary', '') if _data.get('summary', '') else self.name
        self.text = _data.get('command', '') if _data.get('command', '') else self.text

        self.long_summary = _data.get('description', '')
        self.supported_profiles = _data.get('supported-profiles', None)
        self.unsupported_profiles = _data.get('unsupported-profiles', None)

    # alias old params with new
    @property
    def short_summary(self):
        return self.name

    @short_summary.setter
    def short_summary(self, value):
        self.name = value

    @property
    def command(self):
        return self.text

    @command.setter
    def command(self, value):
        self.text = value


class HelpParameter(KnackHelpParameter):  # pylint: disable=too-many-instance-attributes

    def __init__(self, **kwargs):
        super(HelpParameter, self).__init__(**kwargs)

    def update_from_data(self, data):
        super(HelpParameter, self).update_from_data(data)
        # original help.py value_sources are strings, update command strings to value-source dict
        if self.value_sources:
            self.value_sources = [str_or_dict if isinstance(str_or_dict, dict) else {"link": {"command": str_or_dict}}
                                  for str_or_dict in self.value_sources]
