import os
from pathlib import Path
import urllib.parse

# Base directory for the project
BASE_DIR = Path(__file__).parent.parent.parent


class Config:
    """Base configuration class."""

    # Database Configuration
    SQLALCHEMY_DATABASE_URI = os.getenv(
        "DATABASE_URL", f"sqlite:///{BASE_DIR}/data/scriptsmanager.db"
    )
    SQLALCHEMY_TRACK_MODIFICATIONS = False
    
    # PostgreSQL-specific database configuration
    SQLALCHEMY_ENGINE_OPTIONS = {
        'pool_size': 10,
        'pool_timeout': 20,
        'pool_recycle': -1,
        'max_overflow': 0,
        'pool_pre_ping': True,
    }
    
    # Additional database settings for PostgreSQL
    SQLALCHEMY_ECHO = os.getenv("SQLALCHEMY_ECHO", "False").lower() == "true"
    
    @staticmethod
    def get_database_config():
        """Get database configuration based on DATABASE_URL."""
        database_url = os.getenv("DATABASE_URL", f"sqlite:///{BASE_DIR}/data/scriptsmanager.db")
        
        if database_url.startswith('postgresql://'):
            # Parse PostgreSQL URL
            parsed = urllib.parse.urlparse(database_url)
            return {
                'engine': 'postgresql',
                'host': parsed.hostname,
                'port': parsed.port or 5432,
                'database': parsed.path[1:],  # Remove leading slash
                'username': parsed.username,
                'password': parsed.password,
                'url': database_url
            }
        else:
            # SQLite configuration (fallback)
            return {
                'engine': 'sqlite',
                'url': database_url,
                'file': database_url.replace('sqlite:///', '')
            }

    # Application Settings
    SECRET_KEY = os.getenv("SECRET_KEY", "your-secret-key-change-in-production")
    DEBUG = os.getenv("DEBUG", "False").lower() == "true"

    # Multi-user Settings
    BASE_DATA_PATH = Path(os.getenv("BASE_DATA_PATH", "./data"))
    MAX_PROJECTS_PER_USER = int(os.getenv("MAX_PROJECTS_PER_USER", "50"))

    # Port Management
    PORT_RANGE_START = int(os.getenv("PORT_RANGE_START", "5200"))
    PORT_RANGE_END = int(os.getenv("PORT_RANGE_END", "5400"))

    # Backup Configuration
    BACKUP_ENABLED = os.getenv("BACKUP_ENABLED", "True").lower() == "true"
    BACKUP_SCHEDULE_TIME = os.getenv("BACKUP_SCHEDULE_TIME", "02:00")
    BACKUP_RETENTION_DAYS = int(os.getenv("BACKUP_RETENTION_DAYS", "30"))

    # Conda Environment
    CONDA_AUTO_DETECT = os.getenv("CONDA_AUTO_DETECT", "True").lower() == "true"

    # Supported Languages
    SUPPORTED_LANGUAGES = ["en", "es", "it", "fr"]
    DEFAULT_LANGUAGE = os.getenv("DEFAULT_LANGUAGE", "en")

    # Web Interface Management
    WEB_INTERFACE_CONFIG = {
        "port_range": {"start": PORT_RANGE_START, "end": PORT_RANGE_END},
        "session_timeout": 1800,
        "heartbeat_interval": 30,
        "cleanup_interval": 300,
        "max_concurrent_interfaces": 20,
        "max_interfaces_per_user": 5,
    }

    # Documentation Settings
    DOCUMENTATION_CONFIG = {
        "markdown_extensions": ["codehilite", "tables", "toc", "math"],
        "supported_languages": SUPPORTED_LANGUAGES,
        "default_language": DEFAULT_LANGUAGE,
        "enable_math_rendering": True,
        "enable_diagram_rendering": False,
    }

    # Tagging Configuration
    TAGGING_CONFIG = {
        "max_tags_per_script": 20,
        "max_tag_length": 30,
        "allowed_tag_chars": "alphanumeric_underscore_dash",
        "enable_tag_suggestions": True,
    }

    # Security Settings
    SECURITY_CONFIG = {
        "data_directory_permissions": "755",
        "config_file_permissions": "644",
        "enable_project_sharing": False,
        "admin_can_access_all_data": True,
    }


class DevelopmentConfig(Config):
    """Development configuration."""

    DEBUG = True
    
    # Development-specific database settings
    SQLALCHEMY_ENGINE_OPTIONS = {
        'pool_size': 5,
        'pool_timeout': 10,
        'pool_recycle': 300,
        'max_overflow': 0,
        'pool_pre_ping': True,
        'echo': True,  # Log SQL queries in development
    }


class ProductionConfig(Config):
    """Production configuration."""

    DEBUG = False
    
    # Production-specific database settings with connection pooling
    SQLALCHEMY_ENGINE_OPTIONS = {
        'pool_size': 20,
        'pool_timeout': 30,
        'pool_recycle': 3600,  # Recycle connections every hour
        'max_overflow': 10,
        'pool_pre_ping': True,
        'echo': False,  # Disable SQL logging in production
    }
    
    # Production security enhancements
    SECURITY_CONFIG = {
        **Config.SECURITY_CONFIG,
        "enable_project_sharing": True,  # Enable in production
        "session_cookie_secure": True,
        "session_cookie_httponly": True,
        "session_cookie_samesite": "Lax",
    }


class TestingConfig(Config):
    """Testing configuration."""

    TESTING = True
    SQLALCHEMY_DATABASE_URI = "sqlite:///:memory:"
    
    # Testing-specific settings
    SQLALCHEMY_ENGINE_OPTIONS = {
        'pool_size': 1,
        'pool_timeout': 5,
        'pool_recycle': -1,
        'max_overflow': 0,
        'pool_pre_ping': False,
    }
    
    # Disable backup in testing
    BACKUP_ENABLED = False


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