"""
This module translates the results of a HEK query into a VSO query and
returns the results from the VSO query to the user.
"""


from tqdm import tqdm

from sunpy.net import attrs as a
from sunpy.net import hek, vso
from sunpy.net.hek import HEKTable

__all__ = ['translate_results_to_query', 'vso_attribute_parse', 'H2VClient']


def translate_results_to_query(results):
    """
    Formulate VSO queries from HEK results.

    Take the results from a HEK query either in the form of a single HEK
    response or a list containing multiple HEK responses then translates
    them into a VSO compatible query.

    Parameters
    ----------
    results : `sunpy.net.hek.hek.HEKRow` or `sunpy.net.hek.hek.HEKTable`
        The HEK results from a HEK query to be translated.

    Examples
    --------
    >>> from sunpy.net import attrs as a
    >>> from sunpy.net.hek import hek, HEKClient
    >>> from sunpy.net.hek2vso import hek2vso, H2VClient
    >>> h = HEKClient()  # doctest: +REMOTE_DATA
    >>> h2v = H2VClient()  # doctest: +REMOTE_DATA
    >>> q = h.search(a.Time('2011/08/09 07:23:56',
    ...             '2011/08/09 12:40:29'), a.hek.EventType('FL'))  # doctest: +REMOTE_DATA
    >>> len(q)  # doctest: +REMOTE_DATA
    19

    >>> hek2vso.translate_results_to_query(q[0])  # doctest: +REMOTE_DATA
    [[<sunpy.net.attrs.Time(2011-08-08 01:30:04.000, 2011-08-10 00:00:04.000)>, <sunpy.net.attrs.Source(SDO: The Solar Dynamics Observatory.) object at ...>, <sunpy.net.attrs.Instrument: HEK object at ...>, <sunpy.net.attrs.Wavelength(0.0, 0.0, 'Angstrom')>]]
    """
    queries = []
    if isinstance(results, HEKTable):
        for result in results:
            query = vso_attribute_parse(result)
            queries.append(query)
    else:
        query = vso_attribute_parse(results)
        queries.append(query)
    return queries


def vso_attribute_parse(phrase):
    """
    Parses VSO attributes from a HEK result.

    This is a simple function to parse HEK query result and generate a list
    containing VSO relevant attributes.

    Parameters
    ----------
    phrase : `sunpy.net.hek.hek.HEKRow`.
        The single HEK result to be parsed for VSO attribute data.

    Examples
    --------
    >>> from sunpy.net import attrs as a
    >>> from sunpy.net.hek import hek, HEKClient
    >>> from sunpy.net.hek2vso import hek2vso, H2VClient
    >>> h = HEKClient()  # doctest: +REMOTE_DATA
    >>> h2v = H2VClient()  # doctest: +REMOTE_DATA
    >>> q = h.search(a.Time('2011/08/09 07:23:56', '2011/08/09 12:40:29'), a.hek.EventType('FL'))  # doctest: +REMOTE_DATA
    >>> len(q)  # doctest: +REMOTE_DATA
    19
    >>> hek2vso.vso_attribute_parse(q[9])  # doctest: +REMOTE_DATA
    [<sunpy.net.attrs.Time(2011-08-09 07:22:38.000, 2011-08-09 08:32:02.000)>, <sunpy.net.attrs.Source(SDO: The Solar Dynamics Observatory.) object at ...>, <sunpy.net.attrs.Instrument(AIA: Data from the Atmospheric Imaging Assembly instrument.) object at
    ...>, <sunpy.net.attrs.Wavelength(210.99999999999997, 210.99999999999997, 'Angstrom')>]
    """
    try:
        query = [a.Time(phrase['event_starttime'], phrase['event_endtime']),
                 a.Source(phrase['obs_observatory']),
                 a.Instrument(phrase['obs_instrument'])]
        avg_wave_len = phrase['obs_meanwavel']
        query.append(a.Wavelength(avg_wave_len, avg_wave_len))
    except (KeyError, TypeError):
        raise TypeError(f"'{type(phrase)!s}' is an improper data type")
    return query


class H2VClient:
    """
    Class to handle HEK to VSO translations

    Though the single step functions exists outside this class where
    translation is also possible, this class provides a framework where
    all the necessary functionality is easily accessed, along with a few
    additional and helpful methods.

    Examples
    --------
    >>> from sunpy.net.hek import hek
    >>> from sunpy.net import hek2vso
    >>> h2v = hek2vso.H2VClient()  # doctest: +REMOTE_DATA
    """

    def __init__(self):
        self.hek_client = hek.HEKClient()
        self.hek_results = ''
        self.vso_client = vso.VSOClient()
        self.vso_results = []
        self.num_of_records = 0

    def full_query(self, client_query, limit=None):
        """
        An encompassing method that takes a HEK query and returns a VSO result

        Takes a list containing a HEK style query, passes it to a HEKClient
        instance, translates it, queries the VSO webservice, then returns
        the VSO results inside a structured list.

        Parameters
        ----------
        client_query : `list`
            The list containing the HEK style query.
        limit : `int`
            An approximate limit to the desired number of VSO results.

        Examples
        --------
        >>> from sunpy.net import attrs as a, hek, hek2vso
        >>> hek2vso_client = hek2vso.H2VClient()  # doctest: +REMOTE_DATA
        >>> query = hek2vso_client.full_query((a.Time('2011/08/09 07:00:00', '2011/08/09 07:15:00'), a.hek.EventType('FL')))  # doctest: +REMOTE_DATA
        >>> len(query)  # doctest: +REMOTE_DATA
        7
        """
        self._quick_clean()
        self.hek_results = self.hek_client.search(*client_query)
        self._quick_clean()
        return self.translate_and_query(self.hek_results,
                                        limit=limit)

    def translate_and_query(self, hek_results, limit=None):
        """
        Translates HEK results, makes a VSO query, then returns the results.

        Takes the results from a HEK query, translates them, then makes a VSO
        query, returning the results in a list organized by their
        corresponding HEK query.

        Parameters
        ----------
        hek_results : `sunpy.net.hek.hek.HEKRow` or `sunpy.net.hek.hek.HEKTable`
            The results from a HEK query in the form of a list.
        limit : int
            An approximate limit to the desired number of VSO results.

        Examples
        --------
        >>> from sunpy.net import hek, hek2vso
        >>> h = hek.HEKClient()  # doctest: +REMOTE_DATA
        >>> tstart = '2011/08/09 07:23:56'
        >>> tend = '2011/08/09 12:40:29'
        >>> event_type = 'FL'
        >>> q = h.search(a.Time(tstart, tend), a.hek.EventType(event_type))  # doctest: +REMOTE_DATA
        >>> h2v = hek2vso.H2VClient()  # doctest: +SKIP
        >>> res = h2v.translate_and_query(q)  # doctest: +SKIP
        """
        vso_query = translate_results_to_query(hek_results)
        kwargs = {}
        for query in tqdm(vso_query, unit="records"):
            temp = self.vso_client.search(*query, **kwargs)
            self.vso_results.append(temp)
            self.num_of_records += len(temp)
            if limit is not None and self.num_of_records >= limit:
                break

        return self.vso_results

    def _quick_clean(self):
        """
        A simple method to quickly sterilize the instance variables.

        Used to bleach local variables before a new query is made. Not
        intended to be run by user.
        """
        self.vso_results = []
        self.num_of_records = 0
