#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""Convert SeismicX-Cont instrument-response JSON to StationXML.

The response JSON is produced by scripts/download_instrument_responses.py and
stores one response epoch per network/station/location/channel. This converter
rebuilds ObsPy Inventory objects and writes standard StationXML.
"""

from __future__ import annotations

import argparse
import json
import sys
from pathlib import Path

ROOT = Path(__file__).resolve().parents[1]
sys.path.insert(0, str(ROOT))

from obspy.core.inventory import Inventory, Network, Site, Station

from utils.hdf5_waveform_dataset import (
    finite_float,
    inventory_from_response_record,
    response_from_json_record,
    utc_or_none,
)


def matches(value, pattern):
    if pattern in (None, "", "*"):
        return True
    return str(value or "") == str(pattern)


def iter_response_records(path, args):
    with Path(path).open("r", encoding="utf-8") as f:
        obj = json.load(f)

    records = obj.get("responses", [])
    if not isinstance(records, list):
        raise ValueError(f"{path} does not contain a list at key 'responses'")

    n_seen = 0
    for record in records:
        if not matches(record.get("network"), args.network):
            continue
        if not matches(record.get("station"), args.station):
            continue
        if not matches(record.get("location"), args.location):
            continue
        if not matches(record.get("channel"), args.channel):
            continue
        yield record
        n_seen += 1
        if args.limit is not None and n_seen >= args.limit:
            break


def merge_record_inventory(target, record):
    response = response_from_json_record(record)
    one = inventory_from_response_record(record, response)
    one_network = one.networks[0]
    one_station = one_network.stations[0]
    one_channel = one_station.channels[0]

    network = target.get(one_network.code)
    if network is None:
        network = Network(code=one_network.code, stations=[])
        target[one_network.code] = network

    station = None
    for item in network.stations:
        if item.code == one_station.code:
            station = item
            break

    if station is None:
        station = Station(
            code=one_station.code,
            latitude=finite_float(record.get("latitude", 0.0), 0.0),
            longitude=finite_float(record.get("longitude", 0.0), 0.0),
            elevation=finite_float(record.get("elevation_m", 0.0), 0.0),
            site=Site(name=str(record.get("station", ""))),
            channels=[],
            start_date=utc_or_none(record.get("epoch_start")),
            end_date=utc_or_none(record.get("epoch_end")),
        )
        network.stations.append(station)

    station.channels.append(one_channel)


def convert(args):
    networks = {}
    n_records = 0
    n_failed = 0

    for record in iter_response_records(args.input_json, args):
        try:
            merge_record_inventory(networks, record)
            n_records += 1
        except Exception as exc:
            n_failed += 1
            if not args.skip_bad:
                response_id = record.get("response_id", "<unknown>")
                raise RuntimeError(f"failed to convert response {response_id}: {exc}") from exc
            print(
                f"[WARN] skipped bad response {record.get('response_id', '<unknown>')}: {exc}",
                file=sys.stderr,
            )

    inventory = Inventory(
        networks=sorted(networks.values(), key=lambda item: item.code),
        source=args.source,
        sender=args.sender,
    )
    for network in inventory.networks:
        network.stations.sort(key=lambda item: item.code)
        for station in network.stations:
            station.channels.sort(
                key=lambda ch: (
                    ch.location_code or "",
                    ch.code or "",
                    str(ch.start_date or ""),
                    str(ch.end_date or ""),
                )
            )

    args.output_xml.parent.mkdir(parents=True, exist_ok=True)
    inventory.write(str(args.output_xml), format="STATIONXML", validate=args.validate)

    print(f"[OK] wrote {args.output_xml}")
    print(f"[OK] response records converted: {n_records}")
    print(f"[OK] skipped records: {n_failed}")
    print(f"[OK] networks: {len(inventory.networks)}")
    print(f"[OK] stations: {sum(len(net.stations) for net in inventory.networks)}")
    print(
        "[OK] channels: "
        f"{sum(len(sta.channels) for net in inventory.networks for sta in net.stations)}"
    )


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument(
        "--input-json",
        type=Path,
        default=Path("data/response/instrument_responses.json"),
        help="Input SeismicX-Cont instrument-response JSON.",
    )
    parser.add_argument(
        "--output-xml",
        type=Path,
        default=Path("data/response/instrument_responses.stationxml"),
        help="Output StationXML path.",
    )
    parser.add_argument("--network", default="*", help="Optional exact network filter.")
    parser.add_argument("--station", default="*", help="Optional exact station filter.")
    parser.add_argument("--location", default="*", help="Optional exact location filter.")
    parser.add_argument("--channel", default="*", help="Optional exact channel filter.")
    parser.add_argument("--limit", type=int, default=None, help="Optional max records to convert.")
    parser.add_argument("--source", default="SeismicX-Cont response JSON")
    parser.add_argument("--sender", default="SeismicX-Cont")
    parser.add_argument("--skip-bad", action="store_true", help="Skip records that fail conversion.")
    parser.add_argument(
        "--validate",
        action="store_true",
        help="Ask ObsPy/lxml to validate StationXML while writing.",
    )
    args = parser.parse_args()
    convert(args)


if __name__ == "__main__":
    main()