package com.c2kernel.process.module;

import java.io.StringReader;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.Properties;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
import org.xml.sax.InputSource;

import com.c2kernel.common.CannotManageException;
import com.c2kernel.common.ObjectAlreadyExistsException;
import com.c2kernel.common.ObjectCannotBeUpdated;
import com.c2kernel.common.ObjectNotFoundException;
import com.c2kernel.entity.proxy.ItemProxy;
import com.c2kernel.lifecycle.instance.predefined.entitycreation.NewAgent;
import com.c2kernel.lifecycle.instance.predefined.entitycreation.NewItem;
import com.c2kernel.lookup.DomainPath;
import com.c2kernel.process.Bootstrap;
import com.c2kernel.process.Gateway;
import com.c2kernel.scripting.ErrorInfo;
import com.c2kernel.scripting.ScriptingEngineException;
import com.c2kernel.utils.Logger;
import com.c2kernel.utils.Resource;

public class Module {

	public String ns, name;
	public ModuleInfo info;
	public String resURL;
	public ModuleImports imports = new ModuleImports();
	public ArrayList<ModuleConfig> config = new ArrayList<ModuleConfig>();
	public ArrayList<ModuleScript> scripts = new ArrayList<ModuleScript>();
	private static DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
	private DocumentBuilder parser;
	private Document moduleDOM;
    
	static {
        dbf.setValidating(false);
        dbf.setNamespaceAware(false);
	}
	
	public Module() {
		super();
	}
	
	public Module(String moduleXML) throws ModuleException {
		try {
			parser = dbf.newDocumentBuilder();
			moduleDOM = parser.parse(new InputSource(new StringReader(moduleXML)));
		} catch (Exception e) {
			Logger.error(e);
			throw new ModuleException("Could not process modules. XML Parser exception");
		}
		
        Element root = (Element)moduleDOM.getElementsByTagName("CristalModule").item(0);
        
        // Get module metadata
        ns = root.getAttribute("ns");
        name = root.getAttribute("name");
        
        Element infoElem = (Element)moduleDOM.getElementsByTagName("Info").item(0);
        info = new ModuleInfo();
        info.desc = ((Text)infoElem.getElementsByTagName("Description").item(0).getFirstChild()).getData();
        info.version = ((Text)infoElem.getElementsByTagName("Version").item(0).getFirstChild()).getData();
        NodeList nl = infoElem.getElementsByTagName("Dependency");
        for (int i=0; i<nl.getLength();i++)
        	info.dependency.add(((Text)nl.item(i).getFirstChild()).getData());
        
        // register resource URL
        nl = root.getElementsByTagName("ResourceURL");
        if (nl.getLength()>0) {
        	resURL = ((Text)nl.item(0).getFirstChild()).getData();
            Resource.addModuleBaseURL(ns, resURL);
        }
        
        // Get config properties
        nl = root.getElementsByTagName("Config");
        for (int i=0; i<nl.getLength();i++) {
        	Element confElement = (Element)nl.item(i);
        	String target = confElement.getAttribute("target");
        	String name = confElement.getAttribute("name");
        	String value = ((Text)confElement.getFirstChild()).getData();
        	config.add(new ModuleConfig(name, value, target));
        }
        
        // find scripts
        nl = root.getElementsByTagName("Script");
        for (int i=0; i<nl.getLength();i++) {
        	Element confElement = (Element)nl.item(i);
        	String target = confElement.getAttribute("target");
        	String event = confElement.getAttribute("event");
        	String lang = confElement.getAttribute("lang");
        	scripts.add(new ModuleScript(target, event, lang, ((Text)confElement.getFirstChild()).getData()));
        }
        
        // Get imports
        nl = moduleDOM.getElementsByTagName("Imports");
        if (nl.getLength()>0) {
	        Element impElem = (Element)nl.item(0);
	        nl = impElem.getChildNodes();
	        for (int i=0; i<nl.getLength();i++) {
	        	if (!(nl.item(i) instanceof Element)) continue;
	        	Element imp = (Element)nl.item(i);
	        	ModuleImport newImp;
	        	String type = imp.getTagName();
	        	if (type.equals("Resource")) {
	        		ModuleResource newRes = new ModuleResource(imp); 
	        		newImp = newRes;
	        	}
	        	else if (type.equals("Item")) {
	        		NewItem newItem = new NewItem(ns, imp); 
	        		newImp = newItem;
	        	}
	        	else if (type.equals("Agent")) {
	        		NewAgent newAgent = new NewAgent(imp); 
	        		newImp = newAgent;
        		}
	        	else {
	        		Logger.warning("Unknown import type "+type);
	        		continue;
	        	}
	
	        	newImp.name = imp.getAttribute("name");
	        	imports.list.add(newImp);
	        	Logger.msg(8, "Found import "+imports.list.size()+"- "+newImp.name+": "+newImp.getClass().getSimpleName());
	        	
	        }
        }
        
	}
	
	public static com.c2kernel.property.Property newProperty(Element p) {
			return new com.c2kernel.property.Property(p.getAttribute("name"), ((Text)p.getFirstChild()).getData());
	}
	
	public void runScript(String event, boolean isServer) throws ScriptingEngineException {
		for (ModuleScript script : scripts) {
			if (script.shouldRun(event, isServer)) {
				Object result = script.getScript().execute();
				if (result instanceof ErrorInfo) {
					ErrorInfo error = (ErrorInfo) result;
					Logger.error(error.getErrors());
					if (error.getFatal())
						throw new ScriptingEngineException("Fatal Script Error");
				}
				else if (result != null)
					Logger.msg(result.toString());
			}
		}
	}
	
	public void importAll(ItemProxy serverEntity) throws ObjectCannotBeUpdated, ObjectNotFoundException, CannotManageException, ObjectAlreadyExistsException, NoSuchAlgorithmException {
		for (ModuleImport thisImp : imports.list) {
			Logger.msg(5, "Importing "+thisImp.name+" "+thisImp.getClass().getSimpleName());
			if (thisImp instanceof ModuleResource) {
				ModuleResource thisRes = (ModuleResource)thisImp;
				try {
					Bootstrap.verifyResource(ns, thisRes.name, thisRes.resourceType, Resource.getTextResource(ns, thisRes.resourceLocation));
				} catch (Exception ex) {
					Logger.error(ex);
				}
			}
			else if (thisImp instanceof NewItem) {
				NewItem thisItem = (NewItem)thisImp;
				thisItem.ns=ns;
				try {
					new DomainPath(new DomainPath(thisItem.initialPath), thisItem.name).getEntity();
				    Logger.msg(3, "Module.importAll() - Item '"+thisItem.name+"' found.");
				    continue;
				 } catch (ObjectNotFoundException ex) { }
				thisItem.create(Gateway.getLDAPLookup().getRoleManager().getAgentPath("system").getSysKey());
			}
			else if (thisImp instanceof NewAgent) {
				NewAgent thisAgent = (NewAgent)thisImp;
				try {
					Gateway.getLDAPLookup().getRoleManager().getAgentPath(thisAgent.name);
				    Logger.msg(3, "Module.importAll() - User '"+thisAgent.name+"' found.");
				    continue;
				 } catch (ObjectNotFoundException ex) { }
				 Logger.msg("Module.importAll() - User '"+thisAgent.name+"' not found. Creating.");

				thisAgent.create(Gateway.getLDAPLookup().getRoleManager().getAgentPath("system").getSysKey());
			}
		}
	}
	
	public Properties getProperties(boolean isServer) {
		Properties props = new Properties();
		for (ModuleConfig thisProp : config) {
			if (thisProp.include(isServer))
				props.put(thisProp.name, thisProp.value);
		}
		return props;
	}
	
	public String getNs() {
		return ns;
	}
	public String getName() {
		return name;
	}
	public String getDesc() {
		return info.desc;
	}
	public String getVersion() {
		return info.version;
	}
	public String getResURL() {
		return resURL;
	}
	public ArrayList<String> getDependencies() {
		return info.dependency;
	}
	public boolean hasDependency(String dep) {
		return info.dependency.contains(dep);
	}
}