package foundation.icall;

import java.io.File;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

import foundation.action.ActionContext;
import foundation.action.SingletonActionProvider;
import foundation.action.WorkStep;
import foundation.dao.DataPackage;
import foundation.dao.DataReader;
import foundation.dao.DataWriter;
import foundation.dao.IDataLetter;
import foundation.data.entity.Entity;
import foundation.data.object.DataObject;
import foundation.handler.DataPool;
import foundation.handler.ResultPool;
import foundation.icall.callin.BodyReader;
import foundation.icall.callout.HttpServerSource;
import foundation.icall.callout.RemoteSourceBucket;
import foundation.icall.log.LogRecord;
import foundation.io.object.DownloadAction;
import foundation.io.object.DownloadWriter;
import foundation.json.JObjectReader;
import foundation.json.JType;
import foundation.route.Operation;
import foundation.util.Util;


public class ICallCenter extends SingletonActionProvider {

    protected static Logger logger;
    private static ICallCenter instance;
    private static ICallBucket icallBucket;
    
    static {
    	logger = LogManager.getLogger(ICallCenter.class);
    }
    
    private ICallCenter() {
    	icallBucket = ICallBucket.getInstance();
    }

    public static synchronized ICallCenter getInstance() {
        if (instance == null) {
            instance = new ICallCenter();
        }

        return instance;
    }
    
	@Override
	protected void publishMethod() {
		//1. 执行接口
		addMethod("callRemote");
		
		//2. inBound
		addMethod("callIn");
		
		//3. call remote
		addMethod("callRemoteServer");
		
		//4. remote database
		addMethod("callRemoteDB");
		
		//5. 执行 Echo 接口
		addMethod("echo");		
		
		//6. 获取接口描述
		addMethod("getMeta");
		
		//7. 获取接口日志分类树
		addMethod("getLogCategory");
		
		//8. 获取某个具体接口的日志列表
		addMethod("getLogList");
		
		//9. 获取某个具体请求的Request日志
		addMethod("getRequestFile");
		
		//10. 获取某个具体请求的Response日志
		addMethod("getResponseFile");
		
		//11. 重新加载接口参数
		addMethod("reloadInterfaceSource");
	}
	
	public void callRemote(ActionContext context, ICall iCall) throws Exception {
		ICallDirection direction = iCall.getType();
		
		if (ICallDirection.RemoteServer == direction) {
			callRemoteServer(context, iCall);
		}
		else if (ICallDirection.RemoteDB == direction) {
			callRemoteDB(context, iCall);
		}
	}
	
	public void callIn(ActionContext context, ICall iCall) throws Exception {
		DataWriter dataWriter = context.getDataWriter();
		InboundResult result = new InboundResult(iCall);
		
		//1. get data package
		String dataName = iCall.getDataName();
		DataPackage dataPackage = DataPackage.getInstance(dataName);
		
		if (dataPackage == null) {
			throw new Exception("call in bound error, invalid data name: " + dataName);
		}
		
		//2. get request data
		DataReader requestReader = context.getDataReader();
		
		if (!requestReader.has(IDataLetter.Data)) {
			dataWriter.reportOneError("DataNotExists", "data not exists in request");
			logger.error("absent data interface call, skip");
			return;
		}
		
		JObjectReader dataReader = requestReader.getReader(IDataLetter.Data, JType.Object);
		
		//3. 加载DataPackage
		BodyReader bodyReader = new BodyReader(dataReader, dataPackage, iCall.getMappings());
		int received = bodyReader.parse();
		result.setReceived(received);
		
		//4. 保存数据到数据库
		if (!dataPackage.isEmpty()) {
			int saved = dataPackage.saveOneDataToPersist();
			result.setSaved(saved);
		}
		
		//5. result
		dataWriter.addValue(result);		
	}
	
	private void callRemoteServer(ActionContext context, ICall iCall) throws Exception {
		DataWriter dataWriter = context.getDataWriter();
		OutboundResult result = new OutboundResult(iCall);
		
		//1. get data package
		DataPackage dataPackage = context.getDataPackage();
		
		if (dataPackage != null) {
			DataPackage host = dataPackage.getHost();

			if (host != null) {
				host.setMasterId(dataPackage.getHostID());
				host.loadOneDataFromFile(); 
				
				dataPackage = host;
			}
		}
		
		//2. 调用 远端接口
		HttpServerSource source = iCall.remoteSource();
		
		source.login(context, iCall);
		try {
			iCall.sendRemoteServerCall(context, result);
		}
		finally {
			source.logout(context, iCall);
		}			
		
		//4. result
		dataWriter.addValue(result);
	}
	
	private void callRemoteDB(ActionContext context, ICall iCall) throws Exception {
		DataWriter dataWriter = context.getDataWriter();
		OutboundResult result = new OutboundResult(iCall);
		LogRecord record = new LogRecord(iCall);
		result.setRecord(record);
		
		//1. 运行远程SQL
		iCall.sendRemoteDBCall(context, result);
		
		//2. result
		if (dataWriter != null) {
			dataWriter.addValue(result);
		}
	}

	public void echo(ActionContext context, ICall iCall) throws Exception {
		DataWriter dataWriter = context.getDataWriter();
		InboundResult result = new InboundResult(iCall);
		
		//1. try get data package
		String dataName = iCall.getDataName();
		DataPackage dataPackage = DataPackage.getInstance(dataName);
		
		//2. try get request data
		DataReader requestReader = context.getDataReader();
		JObjectReader dataReader = requestReader.getReader(IDataLetter.Data, JType.Object);
		
		//3. 加载DataPackage
		BodyReader bodyReader = new BodyReader(dataReader, dataPackage, iCall.getMappings());
		int received = bodyReader.parse();
		result.setReceived(received);
		
		//4. 保存数据到数据库
		result.setResponseBody(requestReader.getBody());
		
		//5. result
		dataWriter.addValue(result);
	}
	
	public void getMeta(ActionContext context, ICall iCall) throws Exception {
		DataWriter dataWriter = context.getDataWriter();
		ICallMeta meta = iCall.getMeta();
		dataWriter.addValue(meta);
	}

	public void getRequestFile(ActionContext context, ICall iCall) throws Exception {
		DataWriter dataWriter = context.getDataWriter();
		DataReader dataReader = context.getDataReader();
		
		//1. 从请求中得到日志ID
		String id = dataReader.getString("id");
		
		if (Util.isEmpty(id)) {
			logger.error("request has no id");
			return;
		}
		
		//2. 获取数据文件
		DataObject dataObject = DataObject.getInstance("sys_interface_log");
		Entity entity = dataObject.getTableEntity(id);
		
		if (entity == null) {
			logger.error("log record not exists");
			return;
		}
		
		String path = entity.getString("request_content");
		File file = new File(path);
		
		if (!file.exists()) { 
			logger.error("file not exists: {}", file);
			return;
		}
		
		//3. 返回文件流
		DownloadWriter downloadWriter = new DownloadWriter(dataWriter);
		downloadWriter.write(file, "requestbody", DownloadAction.ASTexT);
	}
	
	public void getResponseFile(ActionContext context, String method) throws Exception {
		DataWriter dataWriter = context.getDataWriter();
		DataReader dataReader = context.getDataReader();
		
		//1. 从请求中得到日志ID
		String id = dataReader.getString("id");
		
		if (Util.isEmpty(id)) {
			logger.error("request has no id");
			return;
		}
		
		//2. 获取数据文件
		DataObject dataObject = DataObject.getInstance("sys_interface_log");
		Entity entity = dataObject.getTableEntity(id);
		
		if (entity == null) {
			logger.error("log record not exists");
			return;
		}
		
		String path = entity.getString("return_content");
		File file = new File(path);
		
		if (!file.exists()) {
			logger.error("file not exists: {}", file);
			return;
		}
		
		//3. 返回文件流
		DownloadWriter downloadWriter = new DownloadWriter(dataWriter);
		downloadWriter.write(file, "responsebody", DownloadAction.ASTexT);
	}
	
	@Override
	public void exec(ActionContext context, String methodName) throws Exception {
		String iCallName = context.getStepParam();
		
		if (Util.isEmpty(iCallName)) {
			DataReader dataReader = context.getDataReader();
			iCallName = dataReader.getString("icall");
		}
		
		ICall iCall = icallBucket.getOne(iCallName);
		
		Method method = getMethod(methodName);
		try {
			method.invoke(this, context, iCall);
		}
		catch (InvocationTargetException e) {
			e.printStackTrace();
			Throwable throwable = e.getTargetException();

			if (throwable == null) {
				throw e;
			}
			else {
				throw (Exception) throwable;
			}
		}
		catch (Exception e) {
			e.printStackTrace();
			throw e;
		}
	}

	@Override
	protected void invokeMethod(Method method, DataPool dataPool, ResultPool resultPool) throws Exception {
		//1. 创建 reader 和 writer
		Operation operation = dataPool.getOperation();
		DataReader dataReader = new DataReader(operation, dataPool);
		
		DataWriter dataWriter = new DataWriter(resultPool, dataReader.getDomain());
		resultPool.setLetterWriter(dataWriter);
		
		//2. 创建 ICall, 请求样例-inbound：root/interface/call/md_org_data
		//2. 每次请求系统都会根据 meta 创建一个新的 iCall 和 remote source
		String iCallName = dataReader.getString("icall");
		ICall iCall = icallBucket.getOne(iCallName);
		
		//3. 创建 action context
		String dataName = dataReader.getDomain().getDataName();
		WorkStep step = new WorkStep(dataName, operation.getOperator());
		ActionContext context = new ActionContext(dataReader, dataWriter, step);
		
		//4. 调用方法
		try {
			method.invoke(this, context, iCall);
		}
		catch (InvocationTargetException e) {
			e.printStackTrace();
			Throwable throwable = e.getTargetException();

			if (throwable == null) {
				throw e;
			}
			else {
				throw (Exception) throwable;
			}
		}		
	}
	
	@Override
	protected boolean validateMethodParameter(Class<?>[] parameters) {
		if (parameters == null || parameters.length != 2) {
			return false;
		}
		
		Class<?> type = parameters[0];
		if (!type.isAssignableFrom(ActionContext.class)) {
			return false;
		};
		
		type = parameters[1];
		if (!type.isAssignableFrom(ICall.class)) {
			return false;
		};
		
		return true;
	}

	public void reloadInterfaceSource(ActionContext context, ICall iCall) throws Exception {
		RemoteSourceBucket sourceBucket = RemoteSourceBucket.clean();
		
		ICallLoader.loadRemoteDataBases(sourceBucket);
		ICallLoader.loadHttpServers(sourceBucket);
	}
}