import os
from typing import Optional

class Settings:
    # API Keys
    OPENAI_API_KEY: Optional[str] = os.getenv("OPENAI_API_KEY")
    ANTHROPIC_API_KEY: Optional[str] = os.getenv("ANTHROPIC_API_KEY")
    QWEN_API_KEY: Optional[str] = os.getenv("QWEN_API_KEY")
    
    # Third-party provider API keys
    OPENROUTER_API_KEY: Optional[str] = os.getenv("OPENROUTER_API_KEY")
    SILICONFLOW_API_KEY: Optional[str] = os.getenv("SILICONFLOW_API_KEY")
    
    # API Base URLs (支持中转站)
    OPENAI_API_BASE: Optional[str] = os.getenv("OPENAI_API_BASE", "https://api.openai.com/v1")
    ANTHROPIC_API_BASE: Optional[str] = os.getenv("ANTHROPIC_API_BASE", "https://api.anthropic.com/v1")
    QWEN_API_BASE: Optional[str] = os.getenv("QWEN_API_BASE", "https://dashscope.aliyuncs.com/api/v1")
    
    # Third-party provider API base URLs
    OPENROUTER_API_BASE: Optional[str] = os.getenv("OPENROUTER_API_BASE", "https://openrouter.ai/api/v1")
    SILICONFLOW_API_BASE: Optional[str] = os.getenv("SILICONFLOW_API_BASE", "https://api.siliconflow.cn/v1")
    
    # Model settings
    EMBEDDING_MODEL = "text-embedding-ada-002"
    GENERATION_MODEL = "gpt-3.5-turbo"
    
    # Model provider settings
    EMBEDDING_PROVIDER = "openai"  # openai, anthropic, qwen, openrouter, siliconflow
    GENERATION_PROVIDER = "openai"  # openai, anthropic, qwen, openrouter, siliconflow
    
    # Processing settings
    BATCH_SIZE = 50
    MAX_RETRIES = 3
    RETRY_DELAY = 2
    
    # Retrieval settings
    TOP_K = 8
    MIN_SEGMENT_LENGTH = 50
    
    # Generation settings
    TEMPERATURE = 0.25
    MAX_TOKENS_FACTOR = 2
    
    # Storage settings
    VECTOR_INDEX_FILE = "vector_index.faiss"
    METADATA_FILE = "metadata.json"
    
    # Upload settings
    MAX_FILES = 20  # 更新为20个文件
    UPLOAD_FOLDER = "uploads"
    
    # Celery settings
    CELERY_BROKER_URL = "redis://localhost:6379/0"
    CELERY_RESULT_BACKEND = "redis://localhost:6379/0"
    
settings = Settings()