#!/usr/bin/env python
# -*- coding: utf-8 -*-
##*******************************************************************************
# @Author: Anne Philipp (University of Vienna)
#
# @Date: November 2018
#
# @Change History:
#
# @License:
#    (C) Copyright 2014-2018.
#
#    This software is licensed under the terms of the Apache Licence Version 2.0
#    which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
#
# @Modul Description:
#
#
# @Module Content:

#
#*******************************************************************************

# ------------------------------------------------------------------------------
# MODULES
# ------------------------------------------------------------------------------

import _config
# ------------------------------------------------------------------------------
# FUNCTIONS
# ------------------------------------------------------------------------------


def check_grid(grid):
    '''Convert grid into correct Lat/Lon format. E.g. '0.5/0.5'

    Checks on format of original grid. Wether it is in the order of 1000 or 1.
    Convert to correct grid format and substitute into "Lat/Lon" format string.

    Parameters
    ----------
    grid : :obj:`string`
        Contains grid information

    Return
    ------
    grid : :obj:``string`
        Contains grid in format Lat/lon. E.g. 0.1/0.1
    '''

    if 'N' in grid:
        return grid
    if '/' in grid:
        gridx, gridy = grid.split('/')
        if gridx == gridy:
            grid = gridx
        else:
            raise ValueError('GRID parameter contains two values '
                             'which are unequal %s' (grid))
    # determine grid format
    if float(grid) / 100. >= 0.5:
        # grid is defined in 1/1000 degrees; old format
        grid = '{}/{}'.format(float(grid) / 1000.,
                              float(grid) / 1000.)
    elif float(grid) / 100. < 0.5:
        # grid is defined in normal degree; new format
        grid = '{}/{}'.format(float(grid), float(grid))

    return grid

def check_area(grid, area, upper, lower, left , right):
    '''Defines the correct area string.

    Checks on the format of the four area components. Wether it is of
    the order of 1000 or 1. Also checks wether area was already set by command
    line, then the four components are overwritten.
    Convert to correct format of the order of magnitude "1" and sets the
    area parameter (North/West/South/East).
    E.g.: -5./20./10./10.

    Parameters
    ----------
    grid : :obj:`string`
        Contains grid information

    Return
    ------
    grid : :obj:``string`
        Contains grid in format Lat/lon. E.g. 0.1/0.1
    '''
    if 'N' in grid:  # Gaussian output grid
        area = 'G'
        return area

    # if area was provided decompose area into its 4 components
    if area:
        components = area.split('/')
        upper, left, lower, right = components

    # determine area format
    if (abs(float(upper) / 1000.) >= 0.05 and
        abs(float(lower) / 1000.) >= 0.05 and
        abs(float(left) / 1000.) >= 0.05 and
        abs(float(right) / 1000.) >= 0.05):
        # area is defined in 1/1000 degrees; old format
        area = '{}/{}/{}/{}'.format(float(upper) / 1000.,
                                    float(left) / 1000.,
                                    float(lower) / 1000.,
                                    float(right) / 1000.)
    elif (abs(float(upper) / 1000.) < 0.05 and
          abs(float(lower) / 1000.) < 0.05 and
          abs(float(left) / 1000.) < 0.05 and
          abs(float(right) / 1000.) < 0.05):
        # area is already in new format
        area = '{}/{}/{}/{}'.format(float(upper),
                                    float(left),
                                    float(lower),
                                    float(right))
    else:
        raise ValueError('The area components have different '
                         'formats (upper, lower, left, right): '
                         '{}/{}/{}/{}'.format(str(upper), str(lower),
                                              str(left) , str(right)))

    return area

def check_levels(levelist, level):
    '''Defines correct level list and guarantees that the maximum level is
    one of the available maximum levels.

    Parameters
    ----------
    levelist : :obj:`string`
        Specifies the level list.
        Examples: model level: 1/to/137, pressure levels: 500/to/1000

    level : :obj:`string`
        Specifies the maximum level.

    Return
    ------
    levelist : :obj:`string`
        Specifies the required levels. It has to have a valid
        correspondence to the selected levtype.
        Examples: model level: 1/to/137, pressure levels: 500/to/1000

    level : :obj:`string`
        Specifies the maximum level. It has to be one of the
        available maximum level number as contained in the variable
        MAX_LEVEL_LIST in "_config". E.g. [16, 19, 31, 40, 50, 60, 62, 91, 137]

    '''
    # assure consistency of levelist and level
    if not levelist and not level:
        raise ValueError('ERROR: neither levelist nor level '
                         'specified in CONTROL file')
    elif not levelist and level:
        levelist = '1/to/' + level
    elif (levelist and not level) or \
         (levelist[-1] != level[-1]):
        level = levelist.split('/')[-1]
    else:
        pass

    # check if max level is a valid level
    if int(level) not in _config.MAX_LEVEL_LIST:
        raise ValueError('ERROR: \n'
                         'LEVEL must be the maximum level of a specified '
                         'level list from ECMWF, e.g. {} \n'
                         'Check parameter "LEVEL" or the max level of '
                         '"LEVELIST"!'.format(str(_config.MAX_LEVEL_LIST)))

    return levelist, level


def check_ppid(c, ppid):
    '''Sets the current PPID.

    Parameters
    ----------
    c : :obj:`ControlFile`
            Contains all the parameters of CONTROL file and
            command line.

    ppid : :obj:`int` or :obj:`None`
        Contains the ppid number provided by the command line parameter
        of is None otherwise.

    Return
    ------

    '''

    if not ppid:
        c.ppid = str(os.getppid())
    else:
        c.ppid = ppid

    return


def check_purefc(type):
    '''Check for a pure forecast mode.

    Parameters
    ----------
    type : :obj:`list` of :obj:`string`
        List of field types.

    Return
    ------
    True or False:
        True if pure forecasts are to be retrieved. False if there are
        analysis fields in between.
    '''

    if 'AN' not in type and '4V' not in type:
        # pure forecast
        return True

    return False


def check_():
    '''

    Parameters
    ----------
    par : :obj:``
        ...

    Return
    ------

    '''
    return