from yuxi.channels.models import ChannelIdentity, ChannelType
from yuxi.channels.adapters.signal.normalize import normalize_e164


def resolve_thread(identity: ChannelIdentity, agent_id: str = "main") -> str:
    chat_id = identity.channel_chat_id
    channel_type = identity.channel_type

    if channel_type != ChannelType.SIGNAL:
        raise ValueError(f"Unexpected channel type: {channel_type}")

    if chat_id.startswith("group:"):
        group_id = chat_id.removeprefix("group:")
        return f"agent:{agent_id}:signal:group:{group_id}"

    normalized = normalize_e164(chat_id)
    return f"agent:{agent_id}:signal:dm:{normalized}"