import os
import sys
from dotenv import load_dotenv

load_dotenv()


def get_base_dir() -> str:
    """Get base directory, supporting PyInstaller frozen executables."""
    if getattr(sys, "frozen", False):
        # Running as PyInstaller bundle
        return os.path.dirname(sys.executable)
    else:
        # Running as script - go up two levels from app/config.py to backend/
        return os.path.dirname(os.path.dirname(os.path.abspath(__file__)))


def get_app_data_dir() -> str:
    """Get persistent app data directory for storing user data.

    This directory persists across application restarts, unlike temp folders
    used by portable executables.

    Returns:
        Windows: %APPDATA%/Meeting-Assistant
        macOS: ~/Library/Application Support/Meeting-Assistant
        Linux: ~/.config/meeting-assistant
    """
    if sys.platform == "win32":
        # Windows: Use APPDATA
        base = os.environ.get("APPDATA", os.path.expanduser("~"))
        return os.path.join(base, "Meeting-Assistant")
    elif sys.platform == "darwin":
        # macOS: Use Application Support
        return os.path.expanduser("~/Library/Application Support/Meeting-Assistant")
    else:
        # Linux: Use XDG config or fallback to ~/.config
        xdg_config = os.environ.get("XDG_CONFIG_HOME", os.path.expanduser("~/.config"))
        return os.path.join(xdg_config, "meeting-assistant")


class Settings:
    # Server Configuration
    BACKEND_HOST: str = os.getenv("BACKEND_HOST", "0.0.0.0")
    BACKEND_PORT: int = int(os.getenv("BACKEND_PORT", "8000"))

    # Database Configuration
    DB_TYPE: str = os.getenv("DB_TYPE", "mysql")  # "mysql" or "sqlite"
    SQLITE_PATH: str = os.getenv("SQLITE_PATH", "data/meeting.db")
    DB_HOST: str = os.getenv("DB_HOST", "mysql.theaken.com")
    DB_PORT: int = int(os.getenv("DB_PORT", "33306"))
    DB_USER: str = os.getenv("DB_USER", "A060")
    DB_PASS: str = os.getenv("DB_PASS", "")
    DB_NAME: str = os.getenv("DB_NAME", "db_A060")
    DB_POOL_SIZE: int = int(os.getenv("DB_POOL_SIZE", "5"))

    # External API Configuration
    AUTH_API_URL: str = os.getenv(
        "AUTH_API_URL", "https://pj-auth-api.vercel.app/api/auth/login"
    )
    DIFY_API_URL: str = os.getenv("DIFY_API_URL", "https://dify.theaken.com/v1")
    DIFY_API_KEY: str = os.getenv("DIFY_API_KEY", "")
    DIFY_STT_API_KEY: str = os.getenv("DIFY_STT_API_KEY", "")

    # Authentication Configuration
    ADMIN_EMAIL: str = os.getenv("ADMIN_EMAIL", "ymirliu@panjit.com.tw")
    JWT_SECRET: str = os.getenv("JWT_SECRET", "meeting-assistant-secret")
    JWT_EXPIRE_HOURS: int = int(os.getenv("JWT_EXPIRE_HOURS", "24"))

    # Timeout Configuration (in milliseconds)
    UPLOAD_TIMEOUT: int = int(os.getenv("UPLOAD_TIMEOUT", "600000"))  # 10 minutes
    DIFY_STT_TIMEOUT: int = int(os.getenv("DIFY_STT_TIMEOUT", "300000"))  # 5 minutes
    LLM_TIMEOUT: int = int(os.getenv("LLM_TIMEOUT", "120000"))  # 2 minutes
    AUTH_TIMEOUT: int = int(os.getenv("AUTH_TIMEOUT", "30000"))  # 30 seconds

    # File Configuration
    TEMPLATE_DIR: str = os.getenv("TEMPLATE_DIR", "")
    RECORD_DIR: str = os.getenv("RECORD_DIR", "")
    MAX_FILE_SIZE: int = int(os.getenv("MAX_FILE_SIZE", str(500 * 1024 * 1024)))  # 500MB
    SUPPORTED_AUDIO_FORMATS: str = os.getenv(
        "SUPPORTED_AUDIO_FORMATS", ".mp3,.wav,.m4a,.webm,.ogg,.flac,.aac"
    )

    @property
    def supported_audio_formats_set(self) -> set:
        """Return supported audio formats as a set."""
        return set(self.SUPPORTED_AUDIO_FORMATS.split(","))

    def get_template_dir(self, base_dir: str | None = None) -> str:
        """Get template directory path, resolving relative paths.

        Args:
            base_dir: Base directory for relative paths. If None, uses get_base_dir()
                     which supports frozen executables.
        """
        if base_dir is None:
            base_dir = get_base_dir()
        if self.TEMPLATE_DIR:
            if os.path.isabs(self.TEMPLATE_DIR):
                return self.TEMPLATE_DIR
            return os.path.join(base_dir, self.TEMPLATE_DIR)
        return os.path.join(base_dir, "template")

    def get_record_dir(self, base_dir: str | None = None) -> str:
        """Get record directory path, resolving relative paths.

        Args:
            base_dir: Base directory for relative paths. If None, uses get_base_dir()
                     which supports frozen executables.
        """
        if base_dir is None:
            base_dir = get_base_dir()
        if self.RECORD_DIR:
            if os.path.isabs(self.RECORD_DIR):
                return self.RECORD_DIR
            return os.path.join(base_dir, self.RECORD_DIR)
        return os.path.join(base_dir, "record")

    def get_sqlite_path(self, base_dir: str | None = None) -> str:
        """Get SQLite database file path, resolving relative paths.

        For packaged executables (frozen), uses persistent app data directory
        to survive portable exe cleanup. For development, uses relative path.

        Args:
            base_dir: Base directory for relative paths. If None, auto-detects.
        """
        # If absolute path specified, use it directly
        if self.SQLITE_PATH and os.path.isabs(self.SQLITE_PATH):
            return self.SQLITE_PATH

        # For frozen executables, use persistent app data directory
        # This ensures SQLite data survives portable exe temp cleanup
        if getattr(sys, "frozen", False):
            app_data = get_app_data_dir()
            db_name = os.path.basename(self.SQLITE_PATH) if self.SQLITE_PATH else "meeting.db"
            return os.path.join(app_data, "data", db_name)

        # For development, use relative path from base_dir
        if base_dir is None:
            base_dir = get_base_dir()
        if self.SQLITE_PATH:
            return os.path.join(base_dir, self.SQLITE_PATH)
        return os.path.join(base_dir, "data", "meeting.db")

    # Timeout helpers (convert ms to seconds for httpx)
    @property
    def upload_timeout_seconds(self) -> float:
        return self.UPLOAD_TIMEOUT / 1000.0

    @property
    def dify_stt_timeout_seconds(self) -> float:
        return self.DIFY_STT_TIMEOUT / 1000.0

    @property
    def llm_timeout_seconds(self) -> float:
        return self.LLM_TIMEOUT / 1000.0

    @property
    def auth_timeout_seconds(self) -> float:
        return self.AUTH_TIMEOUT / 1000.0


settings = Settings()