r"""
(extra) K-points with wulfric
*****************************


.. admonition:: Tutorial tasks

    * Get kpoints for future dispersion calculations with |wulfric|_.
    * (extra) Visualize Brillouin zone, k-points and k-path with
      :py:class:`wulfric.PlotlyEngine`.
    * (extra) Create a crystal on |wulfric-FCC|_ lattice with |wulfric|_. Visualize and
      compare primitive and conventional cells. Compute k-points, k-path. Compare
      reciprocal cell of conventional cell, reciprocal cell of primitive cell and
      ``wulfric.Kpoints.rcell``.


One way to get a set of k-points and a k-path in reciprocal space is to use |wulfric|_
package.

We recommend to use its :py:class:`wulfric.Kpoints` interface. Here we provide
not the most straightforward way to interact with it, but the one that gives access
to symmetry information. Note that symmetry search in wulfric is powered by |spglib|_.

Wulfric operates on the crystal structure. First, get the information from |spglib|_ via
wulfric's interface to it.
"""

import wulfric
import magnopy

spinham = magnopy.examples.cubic_ferro_nn(S=1)

spglib_data = wulfric.get_spglib_data(
    cell=spinham.cell,
    atoms=spinham.atoms,
)

# %%
# Next, display the information about the space group or Bravais lattice type

print(spglib_data.space_group_number)
print(spglib_data.crystal_family + spglib_data.centring_type)

# %%
# Now you can create an instance of :py:class:`wulfric.Kpoints` class with one of
# the implemented |wulfric-conventions|_ for the automatic choice of the high-symmetry
# points and k-path.


kp_sc = wulfric.Kpoints.from_crystal(
    cell=spinham.cell,
    atoms=spinham.atoms,
    spglib_data=spglib_data,
    convention="SC",
)

kp_hpkot = wulfric.Kpoints.from_crystal(
    cell=spinham.cell,
    atoms=spinham.atoms,
    spglib_data=spglib_data,
    convention="HPKOT",
)

# magnopy.PlotlyEngine() can be used as well
pe = wulfric.PlotlyEngine(_sphinx_gallery_fix=True)

pe.plot_cell(
    cell=wulfric.cell.get_reciprocal(spinham.cell), legend_label="Reciprocal cell"
)

pe.plot_kpath(kp_sc, legend_label="K-path (SC)", color="GoldenRod", legend_group="SC")
pe.plot_kpoints(
    kp_sc, color="DarkBlue", legend_label="K-points (SC)", legend_group="SC"
)

pe.plot_kpath(
    kp_hpkot, legend_label="K-path (HPKOT)", color="ForestGreen", legend_group="HPKOT"
)
pe.plot_kpoints(
    kp_sc, color="Black", legend_label="K-points (HPKOT)", legend_group="HPKOT"
)

pe.show(axes_visible=False)

# %%
# Default convention is HPKOT

kp = wulfric.Kpoints.from_crystal(
    cell=spinham.cell,
    atoms=spinham.atoms,
    spglib_data=spglib_data,
)


# %%
# The objects above provide a simple interface
#
# *   For calculations (:py:meth:`wulfric.Kpoints.points`)

lswt = magnopy.LSWT(spinham, spin_directions=[[0, 0, 1]])
omegas = [lswt.omega(k=kpoint)[0].real for kpoint in kp.points()]

# %%
# *   And for plotting

import matplotlib.pyplot as plt

_, ax = plt.subplots()

ax.plot(kp.flat_points(), omegas)

ax.set_xticks(kp.ticks(), kp.labels)
ax.vlines(kp.ticks(), 0, 1, transform=ax.get_xaxis_transform(), color="grey", lw=0.5)
ax.set_xlim(kp.ticks()[0], kp.ticks()[-1])

plt.show()

# sphinx_gallery_thumbnail_path = 'img/cat-numbers/6.png'