#!/usr/bin/env python
# coding: utf-8

# You will need to install the following packages:
# - `ipyleaflet`
# - `requests`
# - `xarray`
# - `netcdf4`

# In[ ]:


from ipyleaflet import Map, Velocity, TileLayer, basemaps
import xarray as xr


# In[ ]:


center = [44.33956524809713, -130.60546875000003]
zoom = 3
m = Map(center=center, zoom=zoom, interpolation='nearest', basemap=basemaps.CartoDB.DarkMatter)
m


# In[ ]:


import os

if not os.path.exists('wind-global.nc'):
    url = 'https://github.com/benbovy/xvelmap/raw/master/notebooks/wind-global.nc'
    import requests
    r = requests.get(url)
    wind_data = r.content
    with open('wind-global.nc', 'wb') as f:
        f.write(wind_data)


# In[ ]:


ds = xr.open_dataset('wind-global.nc')
ds


# In[ ]:


display_options = {
    'velocityType': 'Global Wind',
    'displayPosition': 'bottomleft',
    'displayEmptyString': 'No wind data'
}
wind = Velocity(
    data=ds, 
    zonal_speed='u_wind', meridional_speed='v_wind', 
    latitude_dimension='lat', longitude_dimension='lon', 
    velocity_scale=0.01, max_velocity=20, 
    display_options=display_options
)
m.add_layer(wind)