src/services/plugin_service.py

"""
Plugin management service implementation.
"""

import os
import importlib.util
import importlib
import sys
from typing import Dict, List, Optional, Any
from ..interfaces.service_interfaces import IPluginService
from ..interfaces.plugin_interfaces import (
    IPlugin, PluginMetadata, PluginError, 
    PluginInitializationError, PluginDependencyError
)


class PluginService(IPluginService):
    """Service for managing the plugin system."""
    
    def __init__(self, plugins_directory: str = "plugins"):
        self.plugins_directory = plugins_directory
        self.loaded_plugins: Dict[str, IPlugin] = {}
        self.plugin_modules: Dict[str, Any] = {}
        self.game_context: Dict[str, Any] = {}
    
    def set_game_context(self, context: Dict[str, Any]):
        """Set the game context for plugins."""
        self.game_context = context
    
    def load_plugins(self) -> int:
        """Load all plugins from plugins directory."""
        if not os.path.exists(self.plugins_directory):
            os.makedirs(self.plugins_directory)
            print(f"[PluginService] Created plugins directory: {self.plugins_directory}")
            return 0
        
        loaded_count = 0
        plugin_files = [f for f in os.listdir(self.plugins_directory) 
                       if f.endswith('.py') and not f.startswith('__')]
        
        for plugin_file in plugin_files:
            plugin_path = os.path.join(self.plugins_directory, plugin_file)
            if self.load_plugin(plugin_path):
                loaded_count += 1
        
        print(f"[PluginService] Loaded {loaded_count}/{len(plugin_files)} plugins")
        return loaded_count
    
    def load_plugin(self, plugin_path: str) -> bool:
        """Load a specific plugin."""
        try:
            if not os.path.exists(plugin_path):
                print(f"[PluginService] Plugin file not found: {plugin_path}")
                return False
            
            # Extract plugin name from file path
            plugin_name = os.path.splitext(os.path.basename(plugin_path))[0]
            
            # Load module
            spec = importlib.util.spec_from_file_location(plugin_name, plugin_path)
            if not spec or not spec.loader:
                print(f"[PluginService] Failed to create spec for {plugin_path}")
                return False
            
            module = importlib.util.module_from_spec(spec)
            
            # Execute module
            spec.loader.exec_module(module)
              # Find plugin class (should implement IPlugin)
            plugin_class = None
            plugin_candidates = []
            
            for attr_name in dir(module):
                attr = getattr(module, attr_name)
                if (isinstance(attr, type) and 
                    issubclass(attr, IPlugin) and 
                    attr != IPlugin):
                    # Skip interface classes (they usually start with 'I' and are imported)
                    if not (attr_name.startswith('I') and hasattr(attr, '__abstractmethods__') and attr.__abstractmethods__):
                        plugin_candidates.append((attr_name, attr))
            
            # Prefer classes defined in this module (not imported interfaces)
            for attr_name, attr in plugin_candidates:
                if attr.__module__ == module.__name__:
                    plugin_class = attr
                    break
            
            # If no module-local class found, take the first candidate
            if not plugin_class and plugin_candidates:
                plugin_class = plugin_candidates[0][1]
            
            if not plugin_class:
                print(f"[PluginService] No IPlugin implementation found in {plugin_path}")
                return False
            
            # Instantiate plugin
            plugin_instance = plugin_class()
            
            # Check metadata
            metadata = plugin_instance.metadata
            if not isinstance(metadata, PluginMetadata):
                print(f"[PluginService] Invalid metadata in plugin {plugin_name}")
                return False
            
            # Check dependencies
            if not self._check_dependencies(metadata.dependencies):
                print(f"[PluginService] Dependencies not met for plugin {metadata.id}")
                return False
            
            # Initialize plugin
            if not plugin_instance.initialize(self.game_context):
                print(f"[PluginService] Failed to initialize plugin {metadata.id}")
                return False
            
            # Store plugin
            self.loaded_plugins[metadata.id] = plugin_instance
            self.plugin_modules[metadata.id] = module
            
            print(f"[PluginService] Successfully loaded plugin: {metadata.name} v{metadata.version}")
            return True
        
        except Exception as e:
            print(f"[PluginService] Error loading plugin {plugin_path}: {e}")
            return False
    
    def unload_plugin(self, plugin_id: str) -> bool:
        """Unload a plugin."""
        try:
            if plugin_id not in self.loaded_plugins:
                return False
            
            plugin = self.loaded_plugins[plugin_id]
            
            # Shutdown plugin
            plugin.shutdown()
            
            # Remove from loaded plugins
            del self.loaded_plugins[plugin_id]
            
            # Remove module from sys.modules if present
            if plugin_id in self.plugin_modules:
                module = self.plugin_modules[plugin_id]
                module_name = getattr(module, '__name__', None)
                if module_name and module_name in sys.modules:
                    del sys.modules[module_name]
                del self.plugin_modules[plugin_id]
            
            print(f"[PluginService] Unloaded plugin: {plugin_id}")
            return True
        
        except Exception as e:
            print(f"[PluginService] Error unloading plugin {plugin_id}: {e}")
            return False
    
    def get_loaded_plugins(self) -> List[str]:
        """Get list of loaded plugin IDs."""
        return list(self.loaded_plugins.keys())
    
    def reload_plugin(self, plugin_id: str) -> bool:
        """Reload a plugin (hot-reload)."""
        try:
            if plugin_id not in self.loaded_plugins:
                return False
            
            # Get plugin file path
            plugin_files = [f for f in os.listdir(self.plugins_directory) 
                           if f.endswith('.py')]
            
            plugin_file = None
            for f in plugin_files:
                plugin_path = os.path.join(self.plugins_directory, f)
                # Try to match by loading and checking metadata
                # This is a simplified approach
                if plugin_id in f.lower():
                    plugin_file = plugin_path
                    break
            
            if not plugin_file:
                print(f"[PluginService] Could not find file for plugin {plugin_id}")
                return False
            
            # Unload current plugin
            self.unload_plugin(plugin_id)
            
            # Load updated plugin
            return self.load_plugin(plugin_file)
        
        except Exception as e:
            print(f"[PluginService] Error reloading plugin {plugin_id}: {e}")
            return False
    
    def get_plugin(self, plugin_id: str) -> Optional[IPlugin]:
        """Get a loaded plugin instance."""
        return self.loaded_plugins.get(plugin_id)
    
    def get_plugins_by_type(self, plugin_type: str) -> List[IPlugin]:
        """Get all plugins of a specific type."""
        result = []
        for plugin in self.loaded_plugins.values():
            if plugin.metadata.plugin_type.value == plugin_type:
                result.append(plugin)
        return result
    
    def call_plugin_event(self, event_name: str, *args, **kwargs):
        """Call an event on all loaded plugins."""
        for plugin in self.loaded_plugins.values():
            try:
                if hasattr(plugin, event_name):
                    method = getattr(plugin, event_name)
                    if callable(method):
                        method(*args, **kwargs)
            except Exception as e:
                print(f"[PluginService] Error calling {event_name} on plugin {plugin.metadata.id}: {e}")
    
    def get_plugin_status(self, plugin_id: str) -> Optional[Dict[str, Any]]:
        """Get status of a specific plugin."""
        plugin = self.loaded_plugins.get(plugin_id)
        if not plugin:
            return None
        
        try:
            status = plugin.get_status()
            status['metadata'] = {
                'id': plugin.metadata.id,
                'name': plugin.metadata.name,
                'version': plugin.metadata.version,
                'type': plugin.metadata.plugin_type.value,
                'author': plugin.metadata.author
            }
            return status
        except Exception as e:
            return {'error': str(e)}
    
    def get_all_plugin_status(self) -> Dict[str, Dict[str, Any]]:
        """Get status of all loaded plugins."""
        result = {}
        for plugin_id in self.loaded_plugins:
            result[plugin_id] = self.get_plugin_status(plugin_id)
        return result
    
    def _check_dependencies(self, dependencies: List[str]) -> bool:
        """Check if plugin dependencies are satisfied."""
        # For now, just check if dependency plugins are loaded
        for dep in dependencies:
            if dep not in self.loaded_plugins:
                return False
        return True
    
    def create_sample_plugin(self) -> bool:
        """Create a sample plugin file for demonstration."""
        try:
            sample_plugin_content = '''"""
Sample plugin demonstrating the plugin system.
"""

from src.interfaces.plugin_interfaces import IPlugin, PluginMetadata, PluginType
from typing import Dict, Any


class SamplePlugin(IPlugin):
    """Sample plugin implementation."""
    
    @property
    def metadata(self) -> PluginMetadata:
        return PluginMetadata(
            id="sample_plugin",
            name="Sample Plugin",
            version="1.0.0",
            description="A sample plugin demonstrating the plugin system",
            author="MMORPG System",
            plugin_type=PluginType.EVENT,
            dependencies=[],
            config={}
        )
    
    def initialize(self, context: Dict[str, Any]) -> bool:
        """Initialize the plugin."""
        self.context = context
        print("[SamplePlugin] Plugin initialized!")
        return True
    
    def shutdown(self) -> bool:
        """Shutdown the plugin."""
        print("[SamplePlugin] Plugin shutdown!")
        return True
    
    def get_status(self) -> Dict[str, Any]:
        """Get plugin status."""
        return {
            "status": "active",
            "message": "Sample plugin is running normally"
        }
    
    def on_player_join(self, player_id: str) -> None:
        """Called when a player joins."""
        print(f"[SamplePlugin] Player {player_id} joined!")
    
    def on_player_leave(self, player_id: str) -> None:
        """Called when a player leaves."""
        print(f"[SamplePlugin] Player {player_id} left!")
    
    def on_chat_message(self, sender_id: str, message: str, message_type: str) -> None:
        """Called when a chat message is sent."""
        if "hello plugin" in message.lower():
            print(f"[SamplePlugin] Detected greeting from {sender_id}")
'''
            
            sample_path = os.path.join(self.plugins_directory, "sample_plugin.py")
            with open(sample_path, 'w', encoding='utf-8') as f:
                f.write(sample_plugin_content)
            
            print(f"[PluginService] Created sample plugin at {sample_path}")
            return True
        
        except Exception as e:
            print(f"[PluginService] Error creating sample plugin: {e}")
            return False