"""
PySWMM越水結果を2次元氾濫解析向け点源CSVへ変換するサンプル。

出力CSV形式:
    datetime, elapsed_min, node_id, x, y, overflow_m3s

このCSVをANUGA等の2D浅水流モデル側で読み込み、
各マンホール位置に時系列の流入境界・点源として与えます。
"""

from __future__ import annotations

import argparse
from pathlib import Path

import pandas as pd


def export_overflow_sources(timeseries_csv: Path, coord_csv: Path, out_csv: Path) -> pd.DataFrame:
    ts = pd.read_csv(timeseries_csv)
    coords = pd.read_csv(coord_csv)

    nodes = ts[ts["object_type"] == "node"].copy()
    nodes = nodes.rename(columns={"object_id": "node_id"})
    nodes["flooding_m3s"] = nodes["flooding_m3s"].fillna(0.0)
    nodes = nodes[nodes["flooding_m3s"] > 0.0]

    merged = nodes.merge(coords, on="node_id", how="left")
    out = merged[[
        col for col in ["datetime", "elapsed_min", "node_id", "x", "y", "ground_elevation_m", "flooding_m3s"]
        if col in merged.columns
    ]].copy()
    out = out.rename(columns={"flooding_m3s": "overflow_m3s"})

    out_csv.parent.mkdir(parents=True, exist_ok=True)
    out.to_csv(out_csv, index=False)
    return out


def main() -> None:
    parser = argparse.ArgumentParser(description="PySWMM越水結果を2D氾濫解析用点源CSVへ変換します。")
    parser.add_argument("--timeseries", default="../outputs/pyswmm_timeseries.csv")
    parser.add_argument("--coords", default="../data/manhole_coordinates.csv")
    parser.add_argument("--out", default="../outputs/overflow_sources_for_2d.csv")
    args = parser.parse_args()

    base = Path(__file__).resolve().parent
    out = export_overflow_sources(
        (base / args.timeseries).resolve(),
        (base / args.coords).resolve(),
        (base / args.out).resolve(),
    )
    print(f"2D点源CSVを出力しました: {(base / args.out).resolve()}")
    print(out.head().to_string(index=False))


if __name__ == "__main__":
    main()