"""Application configuration, loaded from environment / .env file."""
from functools import lru_cache

from pydantic_settings import BaseSettings, SettingsConfigDict


class Settings(BaseSettings):
    model_config = SettingsConfigDict(env_file=".env", extra="ignore")

    # Qdrant
    qdrant_url: str
    qdrant_api_key: str
    qdrant_collection: str = "documents"

    # MongoDB
    mongodb_uri: str
    mongodb_db: str = "doc_intelligence_rag"

    # LLM via OpenRouter (OpenAI-compatible API)
    openrouter_api_key: str = ""
    openrouter_base_url: str = "https://openrouter.ai/api/v1"
    openrouter_model: str = "anthropic/claude-sonnet-4.6"

    # Embeddings (local, ONNX via fastembed — no torch needed)
    embedding_model: str = "BAAI/bge-small-en-v1.5"
    embedding_dim: int = 384

    # Retrieval / chunking
    chunk_size: int = 900
    chunk_overlap: int = 150
    top_k: int = 5


@lru_cache
def get_settings() -> Settings:
    return Settings()