"""Settings and configuration management."""

import os
from pathlib import Path
from typing import Optional

from dotenv import load_dotenv
from pydantic import Field
from pydantic_settings import BaseSettings

# Load environment variables from .env file
load_dotenv()


class Settings(BaseSettings):
    """Application settings loaded from environment variables."""

    # OpenAI Configuration
    openai_api_key: str = Field(..., description="OpenAI API key")
    openai_model: str = Field(default="gpt-4o-mini", description="OpenAI model to use")
    temperature: float = Field(default=0.7, description="LLM temperature")
    max_tokens: int = Field(default=1000, description="Maximum tokens in response")

    # LangSmith Configuration (optional)
    langchain_tracing_v2: bool = Field(default=False, description="Enable LangSmith tracing")
    langchain_api_key: Optional[str] = Field(default=None, description="LangSmith API key")
    langchain_project: str = Field(
        default="langgraph-agent", description="LangSmith project name"
    )

    # Project Paths
    project_root: Path = Field(
        default_factory=lambda: Path(__file__).parent.parent,
        description="Project root directory",
    )
    docs_dir: Path = Field(
        default_factory=lambda: Path(__file__).parent.parent / "docs",
        description="Documentation directory",
    )

    class Config:
        """Pydantic configuration."""

        env_file = ".env"
        env_file_encoding = "utf-8"
        case_sensitive = False


def get_settings() -> Settings:
    """Get application settings instance."""
    return Settings()

# Made with Bob