"""Application settings — Pydantic v2 style, no module-level singleton.

The container (config/container.py) instantiates Settings once at startup
and passes it down to adapters.  This keeps tests free of singleton state.
"""

from pathlib import Path
from typing import Optional

from pydantic import Field
from pydantic_settings import BaseSettings, SettingsConfigDict


class Settings(BaseSettings):
    """All runtime configuration, sourced from environment variables or a .env file.

    Fields use explicit ``env=`` aliases so the variable names are immediately
    visible and grep-able without needing to know Pydantic's casing rules.
    """

    model_config = SettingsConfigDict(
        env_file=".env",
        env_file_encoding="utf-8",
        # Allow unknown env vars — avoids breakage when the .env file has
        # variables that belong to other services (Discord bot, scripts, etc.).
        extra="ignore",
    )

    # ------------------------------------------------------------------
    # OpenRouter / LLM
    # ------------------------------------------------------------------
    openrouter_api_key: str = Field(default="", alias="OPENROUTER_API_KEY")
    openrouter_model: str = Field(
        default="stepfun/step-3.5-flash:free", alias="OPENROUTER_MODEL"
    )

    # ------------------------------------------------------------------
    # Discord
    # ------------------------------------------------------------------
    discord_bot_token: str = Field(default="", alias="DISCORD_BOT_TOKEN")
    discord_guild_id: Optional[str] = Field(default=None, alias="DISCORD_GUILD_ID")

    # ------------------------------------------------------------------
    # Gitea issue tracker
    # ------------------------------------------------------------------
    gitea_token: str = Field(default="", alias="GITEA_TOKEN")
    gitea_owner: str = Field(default="cal", alias="GITEA_OWNER")
    gitea_repo: str = Field(default="strat-chatbot", alias="GITEA_REPO")
    gitea_base_url: str = Field(
        default="https://git.manticorum.com/api/v1", alias="GITEA_BASE_URL"
    )

    # ------------------------------------------------------------------
    # File-system paths
    # ------------------------------------------------------------------
    data_dir: Path = Field(default=Path("./data"), alias="DATA_DIR")
    rules_dir: Path = Field(default=Path("./data/rules"), alias="RULES_DIR")
    chroma_dir: Path = Field(default=Path("./data/chroma"), alias="CHROMA_DIR")

    # ------------------------------------------------------------------
    # Database
    # ------------------------------------------------------------------
    db_url: str = Field(
        default="sqlite+aiosqlite:///./data/conversations.db", alias="DB_URL"
    )

    # ------------------------------------------------------------------
    # API authentication
    # ------------------------------------------------------------------
    api_secret: str = Field(default="", alias="API_SECRET")

    # ------------------------------------------------------------------
    # Conversation / retrieval tuning
    # ------------------------------------------------------------------
    conversation_ttl: int = Field(default=1800, alias="CONVERSATION_TTL")
    top_k_rules: int = Field(default=10, alias="TOP_K_RULES")
    embedding_model: str = Field(
        default="sentence-transformers/all-MiniLM-L6-v2", alias="EMBEDDING_MODEL"
    )