"""Toy contract seeds for interoperability testing.

This module provides a tiny, self-contained contract seed representing a
LocalProblem-like contract. It is intended for bootstrapping adapter plumbing and
interoperability tests without requiring a full production contract pipeline.
"""
from __future__ import annotations

from nova_plan.contracts import CaCContract, CaCRegistry, sign_ca_contract, SignedCaCContract, SignerStore


def toy_local_problem_contract() -> CaCContract:
    """Return a minimal toy CaCContract representing a LocalProblem seed."""
    contract = CaCContract(
        contract_id="toy-lp",
        version=1,
        content={
            "type": "LocalProblemSeed",
            "domain": "space",
            "assets": ["rover1", "habitat1"],
            "objective": {"type": "min-energy"},
            "constraints": ["deadline<=t", "power<=Pmax"],
        },
    )
    CaCRegistry.register(contract)
    return contract


def sign_toy_contract(signer_id: str) -> "SignedCaCContract | None":
    """Sign the toy contract if a signer key is registered, returning a SignedCaCContract.

    If no signer key exists, this returns None. This keeps MVP semantics simple.
    """
    # Ensure the toy contract exists in the registry
    if CaCRegistry.get("toy-lp") is None:
        toy_local_problem_contract()

    contract = CaCRegistry.get("toy-lp")
    if contract is None:
        return None  # pragma: no cover
    signed = sign_ca_contract(contract, signer_id)
    return signed