"""
Central configuration — single source of truth for all settings.
Loaded from .env via pydantic-settings.

Usage:
    from app.core.config import settings
    print(settings.REDIS_HOST)
"""

from __future__ import annotations

import os
from functools import lru_cache
from typing import Optional


class Settings:
    """Application settings loaded from environment variables."""

    def __init__(self) -> None:
        # Redis
        self.REDIS_HOST: str = os.getenv("REDIS_HOST", "rmi-redis")
        self.REDIS_PORT: int = int(os.getenv("REDIS_PORT", "6379"))
        self.REDIS_PASSWORD: str = os.getenv("REDIS_PASSWORD", "")
        self.REDIS_DB: int = int(os.getenv("REDIS_DB", "0"))

        # Supabase
        self.SUPABASE_URL: str = os.getenv("SUPABASE_URL", "")
        self.SUPABASE_SERVICE_KEY: str = os.getenv("SUPABASE_SERVICE_KEY", "") or os.getenv("SUPABASE_KEY", "")

        # Admin
        self.ADMIN_API_KEY: str = os.getenv("ADMIN_API_KEY", "dev-key-change-me")

        # API Keys
        self.OPENROUTER_API_KEY: str = os.getenv("OPENROUTER_API_KEY", "")
        self.ETHERSCAN_API_KEY: str = os.getenv("ETHERSCAN_API_KEY", "")
        self.HELIUS_API_KEY: str = os.getenv("HELIUS_API_KEY", "")
        self.DEEPSEEK_API_KEY: str = os.getenv("DEEPSEEK_API_KEY", "")
        self.GEMINI_API_KEY: str = os.getenv("GEMINI_API_KEY", "")
        self.GEMINI_API_KEY_2: str = os.getenv("GEMINI_API_KEY_2", "")

        # Langfuse
        self.LANGFUSE_PUBLIC_KEY: str = os.getenv("LANGFUSE_PUBLIC_KEY", "")
        self.LANGFUSE_SECRET_KEY: str = os.getenv("LANGFUSE_SECRET_KEY", "")
        self.LANGFUSE_HOST: str = os.getenv("LANGFUSE_HOST", "http://langfuse-langfuse-web-1:3000")

        # Ollama
        self.OLLAMA_HOST: str = os.getenv("OLLAMA_HOST", "http://ollama:11434")

        # Wallet
        self.WALLET_VAULT_PASSWORD: str = os.getenv("WALLET_VAULT_PASSWORD", "")

        # R2
        self.R2_API_TOKEN: str = os.getenv("R2_API_TOKEN", "")
        self.R2_ACCOUNT_ID: str = os.getenv("R2_ACCOUNT_ID", "")
        self.R2_BUCKET: str = os.getenv("R2_BUCKET", "rag-backup")

    def validate(self) -> list[str]:
        """Return list of missing critical env vars. Empty list = all good."""
        critical = [
            "REDIS_HOST",
            "SUPABASE_URL", 
            "SUPABASE_SERVICE_KEY",
            "ADMIN_API_KEY",
            "WALLET_VAULT_PASSWORD",
        ]
        missing = []
        for var in critical:
            if not getattr(self, var, None):
                missing.append(var)
        return missing


@lru_cache(maxsize=1)
def get_settings() -> Settings:
    """Cached singleton — call this, don't instantiate Settings directly."""
    return Settings()


# Module-level singleton — import this everywhere
settings = get_settings()