"""Nano Banana 节点的展示模型、线路与 API 模型名映射。"""

NANO_BANANA_MODEL_OPTIONS = [
    "Nano Banana 2",
    "Nano Banana Pro",
    "Nano Banana 2 Lite",
    "Nano Banana",
]

NANO_BANANA_ROUTE_OPTIONS = ["畅速", "直连", "专线"]

NANO_BANANA_MODEL_MATRIX = {
    ("Nano Banana Pro", "畅速"): "gemini-3-pro-image-c-sp",
    ("Nano Banana 2", "畅速"): "gemini-3.1-flash-image-c-sp",
    ("Nano Banana 2 Lite", "畅速"): "gemini-3.1-flash-lite-image-c-sp",
    ("Nano Banana", "畅速"): "nano-banana",
    ("Nano Banana Pro", "直连"): "gemini-3-pro-image-c-sd",
    ("Nano Banana 2", "直连"): "gemini-3.1-flash-image-c-sd",
    ("Nano Banana 2 Lite", "直连"): "gemini-3.1-flash-lite-image-c-sd",
    ("Nano Banana", "直连"): "nano-banana",
    ("Nano Banana Pro", "专线"): "gemini-3-pro-image",
    ("Nano Banana 2", "专线"): "gemini-3.1-flash-image",
    ("Nano Banana 2 Lite", "专线"): "gemini-3.1-flash-lite-image",
    ("Nano Banana", "专线"): "gemini-2.5-flash-image",
}

_LEGACY_BILLING_ROUTE_MAP = {
    "特价": "畅速",
    "官方": "专线",
}


def normalize_nano_banana_route(route: str) -> str:
    """兼容旧“计费”值，并校验新模型线路。"""
    normalized = _LEGACY_BILLING_ROUTE_MAP.get(route, route)
    if normalized not in NANO_BANANA_ROUTE_OPTIONS:
        raise ValueError(
            f"模型线路 '{route}' 无效，支持的线路：{', '.join(NANO_BANANA_ROUTE_OPTIONS)}"
        )
    return normalized


def resolve_nano_banana_model(model_name: str, route: str) -> str:
    """由界面模型和模型线路解析实际 API 模型名。"""
    normalized_route = normalize_nano_banana_route(route)
    model = NANO_BANANA_MODEL_MATRIX.get((model_name, normalized_route))
    if model is None:
        raise ValueError(f"模型 '{model_name}' 不支持模型线路 '{normalized_route}'")
    return model