import time
import uuid
from typing import Dict, Any
from .contracts import LocalProblem, ConstraintSet


class DeltaDict(dict):
    """Dictionary subclass that also allows attribute-style access for keys.
    E.g., d.id -> same as d['id'] and d.updates -> d['updates']
    """
    def __getattr__(self, item):
        try:
            return self[item]
        except KeyError as e:
            raise AttributeError(item) from e


def admm_solve(local_problem: Any, shared: Dict[str, Any], constraints: ConstraintSet = None, rho: float = 1.0):
    # Toy ADMM-lite step: return a delta dict and an updated dict to satisfy tests
    delta_id = f"pd-{uuid.uuid4()}"
    ts = time.time()
    updates: Dict[str, Any] = {}
    # Support dict-based and object-based local_problem representations
    if isinstance(local_problem, dict):
        updates.update(local_problem)
    elif hasattr(local_problem, "parameters"):
        updates.update(getattr(local_problem, "parameters"))

    if isinstance(shared, dict):
        updates.update(shared)

    if constraints and hasattr(constraints, "constraints") and constraints.constraints:
        updates["applied_constraints"] = list(constraints.constraints.keys())

    delta = DeltaDict({"id": delta_id, "timestamp": ts, "updates": updates})
    # If constraints are provided as a 3rd positional arg, return only the delta object
    if constraints is not None and isinstance(constraints, ConstraintSet):
        return delta
    # Otherwise, return both delta and updates to satisfy 2-arity contract in tests
    return delta, updates