"""Daemon configuration resolution (REQ-005)."""
from __future__ import annotations

import os
from dataclasses import dataclass


@dataclass(frozen=True)
class DaemonConfig:
    dsn: str
    total_slots: int
    host: str
    port: int

    @staticmethod
    def from_env() -> "DaemonConfig":
        dsn = os.environ.get("TREX_POSTGRESQL_DSN")
        if not dsn:
            raise RuntimeError(
                "TREX_POSTGRESQL_DSN is required to start the slot-core daemon."
            )
        return DaemonConfig(
            dsn=dsn,
            total_slots=int(os.environ.get("TREX_TOTAL_SLOTS", "10")),
            host=os.environ.get("TREX_API_HOST", "127.0.0.1"),
            port=int(os.environ.get("TREX_API_PORT", "8080")),
        )