import importlib
from flask import current_app
from .base import BaseScraper

def get_scraper() -> BaseScraper:
    """Load the configured scraper module dynamically with error handling."""
    from ..models import ScraperModuleConfig, ActivityLog
    
    try:
        # Get module name from database first, fallback to config
        name = ScraperModuleConfig.get_current_module()
        if not name:
            name = current_app.config.get("SCRAPER_MODULE", "dummy")
            
        module = importlib.import_module(f"scipaperloader.scrapers.{name}")
        cls = getattr(module, "Scraper")
        
        # Validate that it's actually a BaseScraper
        if not issubclass(cls, BaseScraper):
            raise TypeError(f"Scraper class in module '{name}' does not inherit from BaseScraper")
            
        return cls()
        
    except (ImportError, AttributeError, TypeError) as e:
        ActivityLog.log_error(
            error_message=f"Failed to load scraper module '{name}': {str(e)}",
            source="scraper_factory",
            severity="error"
        )
        # Fallback to dummy scraper
        from .dummy import Scraper as DummyScraper
        return DummyScraper()

def get_available_scrapers():
    """Get list of available scraper modules."""
    import os
    from scipaperloader.scrapers import __path__ as scrapers_path
    
    modules = []
    scrapers_dir = scrapers_path[0]
    
    for filename in os.listdir(scrapers_dir):
        if filename.endswith(".py") and filename not in ("__init__.py", "base.py", "factory.py"):
            module_name = filename[:-3]
            try:
                # Try to import and validate the module
                module = importlib.import_module(f"scipaperloader.scrapers.{module_name}")
                cls = getattr(module, "Scraper", None)
                if cls and issubclass(cls, BaseScraper):
                    modules.append({
                        "name": module_name,
                        "class": cls,
                        "description": getattr(cls, "__doc__", "No description available")
                    })
            except (ImportError, AttributeError, TypeError):
                # Skip invalid modules
                pass
                
    return modules