# coding=utf-8
from earthdiagnostics.frequency import Frequencies


class ModelingRealm(object):

    def __init__(self, domain_name):
        domain_name = domain_name.lower()
        if domain_name == 'seaice':
            self.name = 'seaIce'
        elif domain_name == 'landice':
            self.name = 'landIce'
        elif domain_name == 'atmoschem':
            self.name = 'atmosChem'
        elif domain_name == 'ocnbgchem':
            self.name = 'ocnBgchem'
        elif domain_name in ['ocean', 'atmos', 'land', 'aerosol']:
            self.name = domain_name
        else:
            raise ValueError('Modelling realm {0} not recognized!'.format(domain_name))

    def __eq__(self, other):
        return other.__class__ == ModelingRealm and self.name == other.name

    def __ne__(self, other):
        return not (self == other)

    def __str__(self):
        return self.name

    def get_table_name(self, frequency, data_convention):
        """
        Returns the table name for a domain-frequency pair
        :param data_convention: Data convention in use
        :type data_convention: str
        :param frequency: variable's frequency
        :type frequency: str
        :return: variable's table name
        :rtype: str
        """
        if frequency in (Frequencies.monthly, Frequencies.climatology, Frequencies.daily):
            if self.name == 'seaIce':
                if data_convention in ('specs', 'preface'):
                    prefix = 'OI'
                else:
                    prefix = 'SI'
            elif self.name == 'landIce':
                prefix = 'LI'
            else:
                prefix = self.name[0].upper()
            table_name = prefix + str(frequency)
        elif frequency == Frequencies.six_hourly:
            table_name = '6hrPlev'
        else:
            table_name = frequency.frequency
        return table_name

    def get_table(self, frequency, data_convention):
        table_name = self.get_table_name(frequency, data_convention)
        from earthdiagnostics.variable import CMORTable
        return CMORTable(table_name, frequency, 'December 2013')


class ModelingRealms(object):
    seaIce = ModelingRealm('seaice')
    ocean = ModelingRealm('ocean')
    landIce = ModelingRealm('landIce')
    atmos = ModelingRealm('atmos')
    land = ModelingRealm('land')
    aerosol = ModelingRealm('aerosol')
    atmosChem = ModelingRealm('atmosChem')
    ocnBgchem = ModelingRealm('ocnBgchem')

    @classmethod
    def parse(cls, modelling_realm):
        """
        Return the basin matching the given name. If the parameter basin is a Basin instance, directly returns the same
        instance. This bahaviour is intended to facilitate the development of methods that can either accept a name
        or a Basin instance to characterize the basin.

        :param modelling_realm: basin name or basin instance
        :type modelling_realm: str | Basin
        :return: basin instance corresponding to the basin name
        :rtype: Basin
        """
        if isinstance(modelling_realm, ModelingRealm):
            return modelling_realm
        for name in cls.__dict__.keys():
            if name.startswith('_'):
                continue
            # noinspection PyCallByClass
            value = cls.__getattribute__(cls, name)
            if isinstance(value, ModelingRealm):
                if modelling_realm.lower() in [value.name.lower()]:
                    return value
        raise ValueError('Modelling realm {0} not recognized!'.format(modelling_realm))