"""
GLAMBIE spinup-geometry (varying geometry, mass-conserving) monthly specific MB.

Post-processes the compiled OGGM `run_with_hydro` regional summary output
(spinup_historical_run_output_RR.nc), already produced by the oggm_prepro
dynamic-spinup pipeline, into a regional + per-glacier netcdf pair with
time-varying (dynamic) glacier area. No OGGM workflow/gdirs/SLURM needed
here: the heavy dynamical modelling already happened upstream, and the
whole computation is vectorized over all glaciers in the region at once.

Environment variables (all required):
  OGGM_HYDRO_SUMMARY_DIR – L4/summary directory containing
                            spinup_historical_run_output_RR.nc and
                            glacier_statistics_RR.csv
  OGGM_OUTDIR             – output directory (both the regional and
                             per-glacier netcdfs land here directly)
  OGGM_RGI_REG            – two-digit GTN-G / RGI region (01-19)
"""
import logging
import os

from oggm import utils

from glambie_helper import spinup_geometry_specific_mb_region

# ---------------------------------------------------------------------------
# Environment
# ---------------------------------------------------------------------------
SUMMARY_DIR = os.environ.get("OGGM_HYDRO_SUMMARY_DIR", "")
if not SUMMARY_DIR:
    raise RuntimeError("Set OGGM_HYDRO_SUMMARY_DIR")

OUTPUT_DIR = os.environ.get("OGGM_OUTDIR", "")
if not OUTPUT_DIR:
    raise RuntimeError("Set OGGM_OUTDIR")

rgi_reg = os.environ.get("OGGM_RGI_REG", "")
if rgi_reg not in [f"{r:02d}" for r in range(1, 20)]:
    raise RuntimeError("Set OGGM_RGI_REG to a two-digit region code (01-19)")

OUTPUT_DIR = utils.mkdir(OUTPUT_DIR)

log = logging.getLogger(__name__)
logging.basicConfig(level=logging.INFO)
log.info(f"Starting GLAMBIE spinup-geometry run for RGI region {rgi_reg}")

# ---------------------------------------------------------------------------
# Compile per-glacier + regional monthly specific MB (1975-01 to 2025-12)
# ---------------------------------------------------------------------------
hydro_nc_path = os.path.join(SUMMARY_DIR, f"spinup_historical_run_output_{rgi_reg}.nc")
rgi_area_csv_path = os.path.join(SUMMARY_DIR, f"glacier_statistics_{rgi_reg}.csv")

reg = spinup_geometry_specific_mb_region(
    hydro_nc_path=hydro_nc_path,
    rgi_area_csv_path=rgi_area_csv_path,
    y0=1975,
    y1=2025,
    outdir=OUTPUT_DIR,
    filesuffix="_v17a_TIModel",
)

log.info(
    f"RGI{rgi_reg}: {int(reg['n_glaciers_success'])}/{int(reg['n_glaciers_total'])} glaciers, "
    f"completion={float(reg['completion_rate_pct']):.2f}%"
)
log.info("GLAMBIE spinup-geometry run complete.")