#
#  Copyright 2025 The InfiniFlow Authors. All Rights Reserved.
#
#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.
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"""
Prevent rag.llm.__init__ from running its heavy auto-discovery loop.

The __init__.py dynamically imports ALL model modules (chat_model,
cv_model, ocr_model, etc.), which pull in deepdoc, xgboost, torch,
and other heavy native deps. We pre-install a lightweight stub for
the rag.llm package so that `from rag.llm.embedding_model import X`
works without triggering the full init.
"""

import os
import sys
import types
from enum import StrEnum

# Resolve the real path to rag/llm/ so sub-module imports can find files
_RAGFLOW_ROOT = os.path.abspath(os.path.join(os.path.dirname(__file__), "..", "..", "..", ".."))
_RAG_LLM_DIR = os.path.join(_RAGFLOW_ROOT, "rag", "llm")


def _install_rag_llm_stub():
    """Replace rag.llm with a minimal package stub if not yet loaded.

    The stub has __path__ pointing to the real rag/llm/ directory so that
    `from rag.llm.embedding_model import X` resolves to the actual file,
    but the __init__.py auto-discovery loop is skipped.
    """
    if "rag.llm" in sys.modules:
        return

    # Create a stub rag.llm package that does NOT run the real __init__
    llm_pkg = types.ModuleType("rag.llm")
    llm_pkg.__path__ = [_RAG_LLM_DIR]
    llm_pkg.__package__ = "rag.llm"
    # Provide empty dicts for the mappings the real __init__ would build
    llm_pkg.EmbeddingModel = {}
    llm_pkg.ChatModel = {}
    llm_pkg.CvModel = {}
    llm_pkg.RerankModel = {}
    llm_pkg.Seq2txtModel = {}
    llm_pkg.TTSModel = {}
    llm_pkg.OcrModel = {}

    class SupportedLiteLLMProvider(StrEnum):
        Tongyi_Qianwen = "Tongyi-Qianwen"
        Dashscope = "Dashscope"
        Moonshot = "Moonshot"
        ZHIPU_AI = "ZHIPU-AI"
        OpenAI = "OpenAI"
        Azure_OpenAI = "Azure-OpenAI"
        HunYuan = "Tencent Hunyuan"

    llm_pkg.SupportedLiteLLMProvider = SupportedLiteLLMProvider
    llm_pkg.FACTORY_DEFAULT_BASE_URL = {}
    llm_pkg.LITELLM_PROVIDER_PREFIX = {}
    sys.modules["rag.llm"] = llm_pkg


_install_rag_llm_stub()
