"""
Finnish snow courses (SYKE)
===========================

The Finnish Environment Institute (Syke) measures SWE along about 150 active
snow courses, once a month from November to May, some since 1947. The open
hydrology API (CC BY 4.0) serves the course SWE (no snow depth or density) and
a derived areal SWE for drainage basins, twice a month.

``SYKEClient`` reads the API, with no account. Every course record is
``"periodic"``. It is not part of ``esd.stations.inventory()`` or ``load()``.

The figures show the active courses, and the monthly SWE at four Lapland
courses since 2010.
"""

import geopandas as gpd
import pandas as pd

import easysnowdata as esd
from easysnowdata.stations.clients import SYKEClient

client = SYKEClient()

# %%
# Every snow course. ``status`` follows Syke's own state: continuous courses
# are Active.
stations = client.get_all_stations()
stations_gdf = gpd.GeoDataFrame(
    pd.DataFrame(stations).set_index("station_id"),
    geometry=gpd.points_from_xy(
        [s["longitude"] for s in stations], [s["latitude"] for s in stations]
    ),
    crs="EPSG:4326",
)
print(stations_gdf["status"].value_counts().to_string())

ax = esd.plotting.points(
    stations_gdf, column="status", legend_label="course", title="Syke snow courses"
)

# %%
# Monthly SWE at four courses north of the Arctic Circle. Each point is one
# survey.
courses = ["1579", "1580", "1581", "1582"]
records = client.get_data(courses, begin_date="2010-09-01")
swe_df = (
    pd.DataFrame(records)
    .assign(date=lambda df: pd.to_datetime(df["date"]))
    .pivot_table(index="date", columns="station_id", values="value")
)
swe_df.columns = [stations_gdf.loc[c, "name"] for c in swe_df.columns]
ax = swe_df.plot(figsize=(10, 4), marker=".", linestyle="none")
ax.set(ylabel="SWE (cm)", title="Snow-course SWE in Lapland")

# %%
# Areal SWE is a separate product: one value per drainage basin on the 1st
# and 16th of each month.
units = client.get_areal_units(active_only=True)
print(f"{len(units)} active areal-SWE units")