""" The configuration from the user.
"""

from collections import OrderedDict
from os import path
import json
from zope import component
from interfaces.message import Error

class Mapping():
    """Represent the configuration. This class is provided as an utility and is
       used in the IDesktop interfaces.
    """

    def __init__(self, configuration):
        self.set(configuration)

    def set(self, configuration):
        """ Associate the mapping defined in the dictionnary.

            Only the lines pointing to a valid file or configuration will be
            loaded.
        """
        init_mapping = configuration["mapping"]
        self.mapping = OrderedDict()
        tmp_mapping = dict(init_mapping)
        for key in tmp_mapping.keys() :
            json_file = init_mapping[key]
            if not path.exists(json_file):
                component.handle(Error(f"The file '{json_file}' does not exists"))
                continue
            with open(json_file, "r") as file:
                json_data = file.read()
                try:
                    j = json.loads(json_data)
                    self.mapping[key] = j
                except json.decoder.JSONDecodeError:
                    component.handle(Error(f"Json syntax error in '{json_file}'"))


    def get(self, key, default):
        """ This function return the mapping associated with the given key.
        """
        return self.mapping.get(key, default)

    def __getitem__(self, key):
        return self.mapping.get(key, None)

    def __setitem__(self, key, value):
        self.mapping[key] = value

    def items(self):
        """ Implement the keys items from the dictionnary
        """
        return self.mapping.items()

    def keys(self):
        """ Implement the keys method from the dictionnary
        """
        return self.mapping.keys()