"""
Class for making sure all category stuff is installed
and works fine.

Copyright (c) Institut Laue-Langevin 2012

@author kieranrcampbell@gmail.com
@modified by NIST/MD sasview team
"""

import json
import logging
import os
from collections import OrderedDict, defaultdict
from contextlib import suppress

from sas.system.user import get_config_dir

logger = logging.getLogger(__name__)

USER_FILE = 'categories.json'

class CategoryInstaller:
    """
    Class for making sure all category stuff is installed

    Note - class is entirely static!
    """

    def __init__(self):
        """ initialization """

    @staticmethod
    def _get_home_dir():
        """
        returns the users sasview config dir
        """
        return get_config_dir()

    @staticmethod
    def _regenerate_model_dict(master_category_dict):
        """
        regenerates self.by_model_dict which has each model name as the key
        and the list of categories belonging to that model
        along with the enabled mapping
        returns tuplet (by_model_dict, model_enabled_dict)
        """
        by_model_dict = defaultdict(list)
        model_enabled_dict = defaultdict(bool)

        for category in master_category_dict:
            for (model, enabled) in master_category_dict[category]:
                by_model_dict[model].append(category)
                model_enabled_dict[model] = enabled

        return (by_model_dict, model_enabled_dict)

    @staticmethod
    def _regenerate_master_dict(by_model_dict, model_enabled_dict):
        """
        regenerates master_category_dict from by_model_dict
        and model_enabled_dict
        returns the master category dictionary
        """
        master_category_dict = defaultdict(list)
        for model in by_model_dict:
            for category in by_model_dict[model]:
                master_category_dict[category].append(\
                    (model, model_enabled_dict[model]))
        return OrderedDict(sorted(list(master_category_dict.items()), key=lambda t: t[0]))

    @staticmethod
    def get_user_file():
        """
        returns the user data file, eg .sasview/categories.json.json
        """
        return os.path.join(CategoryInstaller._get_home_dir(), USER_FILE)

    @staticmethod
    def get_default_file():
        logger.warning("CategoryInstaller.get_default_file is deprecated.")

    @staticmethod
    def check_install(homedir = None, model_list=None):
        """
        the main method of this class
        makes sure categories.json exists and if not
        compile it and install
        :param homefile: Override the default home directory
        :param model_list: List of model names except customized models
        """
        _model_dict = { model.name: model for model in model_list}
        _model_list = list(_model_dict.keys())

        serialized_file = None
        if homedir is None:
            serialized_file = CategoryInstaller.get_user_file()
        else:
            serialized_file = os.path.join(homedir, USER_FILE)
        if os.path.isfile(serialized_file):
            with open(serialized_file, 'rb') as f:
                master_category_dict = json.load(f)
        else:
            master_category_dict = defaultdict(list)

        (by_model_dict, model_enabled_dict) = \
                CategoryInstaller._regenerate_model_dict(master_category_dict)
        add_list = _model_list
        del_name = False
        for cat in list(master_category_dict.keys()):
            for ind in range(len(master_category_dict[cat])):
                model_name, enabled = master_category_dict[cat][ind]
                with suppress(ValueError):
                    add_list.remove(model_name)
                if not enabled:
                    model_enabled_dict.pop(model_name)
        if del_name or (len(add_list) > 0):
            for model in add_list:
                model_enabled_dict[model]= True
                if _model_dict[model].category is None or not _model_dict[model].category:
                    by_model_dict[model].append('Uncategorized')
                else:
                    category = _model_dict[model].category
                    toks = category.split(':')
                    category = toks[-1]
                    toks = category.split('-')
                    capitalized_words = [t.capitalize() for t in toks]
                    category = ' '.join(capitalized_words)

                    by_model_dict[model].append(category)

            master_category_dict = \
                CategoryInstaller._regenerate_master_dict(by_model_dict,
                                                          model_enabled_dict)

            json.dump(master_category_dict, open(serialized_file, "w", encoding="utf8"))

