"""AICC exception hierarchy."""

from __future__ import annotations

from aicc.protocol import ErrorCode


class AICCError(Exception):
    """Base for all AICC SDK errors."""


class ProtocolError(AICCError):
    """Protocol-level error (version mismatch, malformed message)."""


class ConnectionError_(AICCError):
    """Transport / session connection failure."""


class SessionExpiredError(AICCError):
    """Session id is unknown or closed."""


class ToolError(AICCError):
    """Tool execution failure surfaced by the bridge."""

    def __init__(self, code: ErrorCode, message: str, retryable: bool):
        super().__init__(message)
        self.code = code
        self.message = message
        self.retryable = retryable


class CapabilityError(AICCError):
    """Tool requires a capability the agent does not hold."""