#!/usr/bin/env python
"""Build a deterministic model-cost report from an admin usage JSON export."""

from __future__ import annotations

import argparse
import json
from pathlib import Path
import sys


def _repo_root() -> Path:
    return Path(__file__).resolve().parents[1]


def _load_builder():
    api_root = _repo_root() / "apps" / "api"
    sys.path.insert(0, str(api_root))
    from app.services.usage_report import build_model_cost_report

    return build_model_cost_report


def parse_args() -> argparse.Namespace:
    parser = argparse.ArgumentParser(
        description="Create a model/provider AI usage cost report from AdminUsageResponse JSON.",
    )
    parser.add_argument("--input", required=True, help="Path to AdminUsageResponse JSON.")
    parser.add_argument("--output", help="Optional output JSON path. Defaults to stdout.")
    return parser.parse_args()


def main() -> int:
    args = parse_args()
    usage = json.loads(Path(args.input).read_text(encoding="utf-8"))
    report = _load_builder()(usage)
    payload = json.dumps(report, ensure_ascii=False, indent=2, sort_keys=True) + "\n"
    if args.output:
        Path(args.output).write_text(payload, encoding="utf-8")
    else:
        sys.stdout.write(payload)
    return 0


if __name__ == "__main__":
    raise SystemExit(main())