"""Explicit assistant-type registry. Unsupported types never silently degrade."""

from __future__ import annotations

from collections.abc import Callable

from models import AssistantConfig

from services.brains.base import Brain, BrainSpec
from services.brains.dify_brain import DifyBrain
from services.brains.fastgpt_brain import FastGPTBrain
from services.brains.prompt_brain import PromptBrain
from services.brains.workflow_brain import WorkflowBrain


def _workflow(cfg: AssistantConfig) -> Brain:
    return WorkflowBrain(cfg)


BRAIN_FACTORIES: dict[str, Callable[[AssistantConfig], Brain]] = {
    "prompt": lambda cfg: PromptBrain(cfg),
    "workflow": _workflow,
    "dify": lambda _cfg: DifyBrain(),
    "fastgpt": lambda _cfg: FastGPTBrain(),
}

SPECS: dict[str, BrainSpec] = {
    "prompt": PromptBrain.spec,
    "workflow": WorkflowBrain.spec,
    "dify": DifyBrain.spec,
    "fastgpt": FastGPTBrain.spec,
}


def build_brain(cfg: AssistantConfig) -> Brain:
    try:
        factory = BRAIN_FACTORIES[cfg.type]
    except KeyError as exc:
        raise ValueError(f"尚未实现的助手类型: {cfg.type}") from exc
    return factory(cfg)