"""Application configuration settings."""

import os
from urllib.parse import quote_plus

from dotenv import load_dotenv

# Load .env from project root (if present)
load_dotenv()


def build_database_uri():
    """Build a SQLAlchemy MySQL DSN from environment variables.

    Password resolution order:
    1. MYSQL_PASSWORD environment variable
    2. Secret store via keyring (service 'ginger_mysql' and username)
    3. Empty password (not recommended)
    """
    user = os.getenv("MYSQL_USER", "root")
    raw_password = os.getenv("MYSQL_PASSWORD")

    # Try secret store if password not provided in env
    if not raw_password:
        try:
            import keyring

            raw_password = keyring.get_password("ginger_mysql", user)
        except Exception:
            raw_password = None

    password = quote_plus(raw_password or "")
    host = os.getenv("MYSQL_HOST", "127.0.0.1")
    port = os.getenv("MYSQL_PORT", "3306")
    db_name = os.getenv("MYSQL_DB", "flask")
    charset = os.getenv("MYSQL_CHARSET", "utf8mb4")
    return (
        f"mysql+pymysql://{user}:{password}@{host}:{port}/{db_name}"
        f"?charset={charset}"
    )


class BaseConfig:
    """Base configuration shared by all environments."""

    SECRET_KEY = os.getenv("SECRET_KEY", "dev-secret-key")
    DEBUG = False
    TESTING = False

    MYSQL_USER = os.getenv("MYSQL_USER", "root")
    MYSQL_PASSWORD = os.getenv("MYSQL_PASSWORD", "")
    MYSQL_HOST = os.getenv("MYSQL_HOST", "127.0.0.1")
    MYSQL_PORT = os.getenv("MYSQL_PORT", "3306")
    MYSQL_DB = os.getenv("MYSQL_DB", "flask")
    MYSQL_CHARSET = os.getenv("MYSQL_CHARSET", "utf8mb4")
    SQLALCHEMY_DATABASE_URI = build_database_uri()
    SQLALCHEMY_TRACK_MODIFICATIONS = False


class DevelopmentConfig(BaseConfig):
    """Development configurations."""

    DEBUG = True


class ProductionConfig(BaseConfig):
    """Production configurations."""

    DEBUG = False


class TestingConfig(BaseConfig):
    """Testing configurations."""

    TESTING = True
    DEBUG = True


config = {
    "development": DevelopmentConfig,
    "production": ProductionConfig,
    "testing": TestingConfig,
    "default": DevelopmentConfig,
}