import json
import logging
import os
from typing import Optional

# Module-level state for runtime path overrides
_config_path_override: Optional[str] = None
_cookies_path_override: Optional[str] = None


def set_config_path(path: Optional[str]) -> None:
    """
    Set a custom path for config.json at runtime.
    This override takes precedence over environment variables and defaults.

    Note: This uses module-level state and is not thread-safe. Suitable for
    single-threaded CLI usage or single async operations.

    Args:
        path: Absolute or relative path to config file, or None to reset
    """
    global _config_path_override
    _config_path_override = path


def set_cookies_path(path: Optional[str]) -> None:
    """
    Set a custom path for cookies.json at runtime.
    This override takes precedence over environment variables and defaults.

    Note: This uses module-level state and is not thread-safe. Suitable for
    single-threaded CLI usage or single async operations.

    Args:
        path: Absolute or relative path to cookies file, or None to reset
    """
    global _cookies_path_override
    _cookies_path_override = path


def get_config_path() -> str:
    """
    Resolve the configuration file path using priority order:
    1. Runtime override (set_config_path)
    2. Environment variable SCHWAB_CONFIG_PATH
    3. Default locations (../config.json relative to module, then ./config.json)

    Returns:
        str: Path to configuration file
    """
    # Priority 1: Runtime override
    if _config_path_override:
        return _config_path_override

    # Priority 2: Environment variable
    env_path = os.environ.get('SCHWAB_CONFIG_PATH')
    if env_path:
        return env_path

    # Priority 3: Default locations
    # Try package root first (for development/installed package)
    default_path = os.path.join(os.path.dirname(__file__), '..', 'config.json')
    if os.path.exists(default_path):
        return default_path

    # Fall back to current working directory
    return 'config.json'


def get_cookies_path() -> str:
    """
    Resolve the cookies file path using priority order:
    1. Runtime override (set_cookies_path)
    2. Environment variable SCHWAB_COOKIES_PATH
    3. Default location (./cookies.json in CWD)

    Returns:
        str: Path to cookies file
    """
    # Priority 1: Runtime override
    if _cookies_path_override:
        return _cookies_path_override

    # Priority 2: Environment variable
    env_path = os.environ.get('SCHWAB_COOKIES_PATH')
    if env_path:
        return env_path

    # Priority 3: Default location
    return 'cookies.json'


def load_config():
    """Load configuration from config.json (or custom path if configured)"""
    logger = logging.getLogger(__name__)
    config_path = get_config_path()

    try:
        with open(config_path, 'r') as f:
            return json.load(f)
    except FileNotFoundError:
        logger.error(f"config.json not found at {config_path}. Please create one based on config.json.sample")
        return None
    except json.JSONDecodeError:
        logger.error(f"Invalid JSON in config file at {config_path}")
        return None


def get_playwright_url(config=None):
    """Get the Playwright browserless URL from config"""
    import os
    env_url = os.environ.get('SCHWAB_PLAYWRIGHT_URL')
    if env_url:
        return env_url
        
    if config is None:
        config = load_config()

    if config and 'playwright' in config and 'url' in config['playwright']:
        return config['playwright']['url']
    else:
        # Default fallback URL
        return "ws://browser.local.ben.io:3000/playwright/chromium"


def get_schwab_credentials(config=None):
    """Get Schwab credentials from config"""
    if config is None:
        config = load_config()

    if config and 'schwab' in config:
        return config['schwab'].get('username'), config['schwab'].get('password')
    else:
        return None, None