#!/usr/bin/env python
# Wenchang Yang (wenchang@princeton.edu)
# Fri Feb 17 10:30:04 EST 2023
if __name__ == '__main__':
    import sys,os
    from misc.timer import Timer
    tt = Timer(f'[{os.getcwd()}] start ' + ' '.join(sys.argv))
import sys, os.path, os, glob, datetime
import xarray as xr, numpy as np, pandas as pd, matplotlib.pyplot as plt
#more imports
from misc import get_kws_from_argv
#
if __name__ == '__main__':
    tt.check('end import')
#
#start from here
#location: Nepal Lalitpur latitude longitude
locname, lat0, lon0 = 'Lalitpur', 27.6588, 85.3247
dfname = '2m_temperature'
dfname = get_kws_from_argv('dfname', dfname)
daname = {'2m_temperature': 'tas', '2m_temperature_max': 'tasmax', '2m_temperature_min': 'tasmin', 'evaporation': 'evap'}[dfname]
tstart = '1979-01' #param
tstop = '2022-11' if daname=='tas' else '2022-10' #param
trange = pd.date_range(tstart, tstop, freq='MS')
year_month_vec = [(t.year, t.month) for t in trange]
method = 'selnearest' #alternative is interp 
method = get_kws_from_argv('method', method)

ofile = f'era5.{daname}.daily.{method}{locname}.{tstart}_{tstop}.nc'
if os.path.exists(ofile):
    print('[exists]:', ofile)
    xr.open_dataarray(ofile).plot()
    sys.exit()

das = []
for year,month in year_month_vec:
    print(f'{year}-{month:02} of {tstop}')
    #example: ifile = /tigress/wenchang/data/era5/analysis_wy/2m_temperature/daily/era5.2m_temperature.daily.2022-11.nc
    ifile = f'/tigress/wenchang/data/era5/analysis_wy/{dfname}/daily/era5.{dfname}.daily.{year}-{month:02d}.nc'
    print(ifile)
    da = xr.open_dataarray(ifile)
    units = da.attrs['units']
    if method == 'selnearest':
        da = da.sel(latitude=lat0, longitude=lon0, method='nearest')
    elif method == 'interp':
        da = da.interp(latitude=lat0, longitude=lon0)
    da.load()
    das.append(da)
print('concat...')
da = xr.concat(das, dim='time')
#convert units
if dfname.startswith('2m_temperature'):
    da = da - 273.15 #K to C
    da.attrs['units'] = 'degC'
else:
    da.attrs['units'] = units
    

#save
da.to_dataset(name=daname).to_netcdf(ofile)
print('[saved]:', ofile)
 
if __name__ == '__main__':
    from wyconfig import * #my plot settings
    da.plot()
    
    #savefig
    if 'savefig' in sys.argv or 's' in sys.argv:
        figname = __file__.replace('.py', f'.png')
        if 'overwritefig' in sys.argv or 'o' in sys.argv:
            wysavefig(figname, overwritefig=True)
        else:
            wysavefig(figname)
    tt.check(f'**Done**')
    print()
    if 'notshowfig' in sys.argv or 'n' in sys.argv:
        pass
    else:
        if 'plt' in globals(): plt.show()