"""
    This file is part of MSS.

    :copyright: Copyright 2021-2022 by the MSS team, see AUTHORS.
    :license: APACHE-2.0, see LICENSE for details.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
"""

import logging
import warnings
import numpy as np
import matplotlib.pyplot as plt
import mpl_toolkits.axes_grid1.inset_locator
import matplotlib.colors
import mpl_toolkits.basemap
from matplotlib import patheffects
from mslib.mswms.mpl_hsec import MPLBasemapHorizontalSectionStyle
from mslib.mswms.utils import Targets, get_style_parameters, get_cbar_label_format, make_cbar_labels_readable
from mslib.utils import thermolib
from mslib.utils.units import convert_to

class HS_GeopotentialWindStyle_PL(MPLBasemapHorizontalSectionStyle):
    """
    Upper Air Field: Geopotential and Wind
    """
    name = "PLGeopWind"
    title = "Geopotential Height (m) and Horizontal Wind (m/s)"
    styles = [
        ("default", "Wind Speed 10-85 m/s"),
        ("wind_10_105", "Wind Speed 10-105 m/s"),
        ("wind_10_65", "Wind Speed 10-65 m/s"),
        ("wind_20_55", "Wind Speed 20-55 m/s"),
        ("wind_15_55", "Wind Speed 15-55 m/s")]

    # Variables with the highest number of dimensions first (otherwise
    # MFDatasetCommonDims will throw an exception)!
    required_datafields = [
        ("pl", "geopotential_height", "m"),
        ("pl", "eastward_wind", "m/s"),
        ("pl", "northward_wind", "m/s")]

    def _plot_style(self):
        """
        """
        bm = self.bm
        ax = self.bm.ax
        data = self.data

        # Compute wind speed.
        u = data["eastward_wind"]
        v = data["northward_wind"]
        wind = np.hypot(u, v)

        # Plot wind contours.
        # NOTE: Setting alpha=0.8 raises the transparency problem in the client
        # (the imshow issue, see ../issues/transparency; surfaces with alpha
        # values < 1 are mixed with grey). Hence, it is better to disable
        # alpha blending here until a fix has been found. (mr 2011-02-01)
        wind_contours = np.arange(10, 90, 5)  # default wind contours
        if self.style.lower() == "wind_10_65":
            wind_contours = np.arange(10, 70, 5)
        elif self.style.lower() == "wind_20_55":
            wind_contours = np.arange(20, 60, 5)
        elif self.style.lower() == "wind_15_55":
            wind_contours = np.arange(15, 60, 5)
        elif self.style.lower() == "wind_10_105":
            wind_contours = np.arange(10, 110, 5)
        cs = bm.contourf(self.lonmesh, self.latmesh, wind,
                         wind_contours, cmap=plt.cm.inferno_r)
        self.add_colorbar(cs, "Wind Speed (m/s)")

        # Plot geopotential height contours.
        gpm = self.data["geopotential_height"]

        gpm_interval = 20
        if self.level <= 20:
            gpm_interval = 120
        elif self.level <= 100:
            gpm_interval = 80
        elif self.level <= 500:
            gpm_interval = 40

        geop_contours = np.arange(400, 55000, gpm_interval)
        cs = bm.contour(self.lonmesh, self.latmesh, gpm,
                        geop_contours, colors="green", linewidths=2)
        if cs.levels[0] in geop_contours[::2]:
            lablevels = cs.levels[::2]
        else:
            lablevels = cs.levels[1::2]
        ax.clabel(cs, lablevels, fontsize=14, fmt='%.0f')

        # Convert wind data from m/s to knots for the wind barbs.
        uk = convert_to(u, "m/s", "knots")
        vk = convert_to(v, "m/s", "knots")

        # Transform wind vector field to fit map.
        lons2 = ((self.lons + 180) % 360) - 180
        lons2_ind = lons2.argsort()
        udat, vdat, xv, yv = bm.transform_vector(uk[:, lons2_ind], vk[:, lons2_ind],
                                                 lons2[lons2_ind], self.lats,
                                                 16, 16, returnxy=True, masked=True)

        # Plot wind barbs.
        bm.barbs(xv, yv, udat, vdat,
                 barbcolor='firebrick', flagcolor='firebrick', pivot='middle',
                 linewidths=0.5, length=6, zorder=1)

        # Plot title.
        titlestring = "Geopotential Height (m) and Horizontal Wind (m/s) " \
            f"at {self.level:.0f} hPa"
        titlestring += f'\nValid: {self.valid_time.strftime("%a %Y-%m-%d %H:%M UTC")}'
        if self.uses_inittime_dimension():
            time_step = self.valid_time - self.init_time
            time_step_hrs = (time_step.days * 86400 + time_step.seconds) // 3600
            titlestring += f' (step {time_step_hrs:d} hrs from {self.init_time.strftime("%a %Y-%m-%d %H:%M UTC")})'

        if not self.noframe:
            ax.set_title(titlestring,
                         horizontalalignment='left', x=0, fontsize=14)
        else:
            ax.text(bm.llcrnrx, bm.llcrnry, titlestring,
                    fontsize=10, bbox=dict(facecolor='white', alpha=0.6))