"""Configuration for the cloud runtime with conservative inert defaults."""

from __future__ import annotations

from dataclasses import dataclass


@dataclass(frozen=True)
class CloudConfig:
    """Tunable cloud-runtime knobs.

    Defaults are deliberately conservative so importing ``cloud`` is inert
    until a caller actually registers a second host or submits through the SDK.
    """

    # How frequently a host is expected to push its device snapshot. Informational
    # only at runtime (the pool does not run a timer); drives operator expectations.
    sync_interval_seconds: int = 30

    # A host whose ``last_seen_at`` is older than this threshold reports all its
    # devices as ``unreachable`` on the next pool read.
    stale_after_seconds: int = 90

    # Bound on the number of ``queued`` ScheduledTasks. Submissions beyond this
    # are rejected rather than letting the backlog grow without limit.
    max_queue_depth: int = 100

    # Duration of each scheduler-created assignment lease.
    lease_duration_seconds: float = 60.0

    # Strategy name looked up in the AssignmentStrategy registry (default fifo_match).
    default_assignment_strategy: str = "fifo_match"

    # Public SDK URL prefix. Mounted as the FastAPI APIRouter ``prefix``.
    api_version_prefix: str = "/v1"

    # SQLite file path (relative to CWD or absolute) owned by CloudStore.
    db_path: str = "cloud/cloud.sqlite3"