"""
======================================
Searching and downloading from the VSO
======================================

How to download data from the VSO with Fido.
"""
import astropy.units as u

from sunpy.net import Fido
from sunpy.net import attrs as a

###############################################################################
# `sunpy.net.Fido` is the primary interface to search for and download data and
# will search the VSO when appropriate. The following example searches for all
# SOHO/EIT images between the times defined below by defining a
# timerange (`~sunpy.net.attrs.Time`) and the instrument (`~sunpy.net.attrs.Instrument`).

attrs_time = a.Time('2005/01/01 00:10', '2005/01/01 00:15')
result = Fido.search(attrs_time, a.Instrument.eit)

###############################################################################
# Let's inspect the results.

print(result)

###############################################################################
# The following shows how to download the results. If we
# don't provide a path it will download the file into the sunpy data directory.
# The output provides the path of the downloaded files.

downloaded_files = Fido.fetch(result)
print(downloaded_files)

###############################################################################
# More complicated queries can be constructed by using relational operators.
# For example, it is possible to query two wavelengths at the same time with
# the OR operator (|).

result = Fido.search(a.Time('2020/03/04 00:00', '2020/03/04 00:02'),
                     a.Instrument.aia,
                     a.Wavelength(171*u.angstrom) | a.Wavelength(94*u.angstrom))
print(result)

###############################################################################
# We can even combine entire queries in this manner.
# Here we will define two searches for the AIA and HMI data.
# But unlike other examples, we have to ``&`` the individual queries.

search_aia = (a.Time('2020/03/04 00:00', '2020/03/04 00:01') & a.Instrument.aia)
search_hmi = (a.Time('2020/03/04 00:00', '2020/03/04 00:01')
              & a.Instrument.hmi & a.Physobs.los_magnetic_field)

result = Fido.search(search_aia | search_hmi)
print(result)