package org.gcube.data.analysis.rconnector;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;

import javax.inject.Singleton;

import lombok.extern.slf4j.Slf4j;


@Singleton
@Slf4j
public class ConfigFileWriter {


	public boolean write(Info info, String login, String usersHome, String fileName, String scriptToExecute){
		
		if (!usersHome.endsWith("/"))
			usersHome=usersHome+"/";
		File userDir = new File(usersHome+login);
		File configFile= new File(userDir, fileName);
		checkDirectory(userDir, login, scriptToExecute);
		return writeFile(info, configFile);
	}

	private void checkDirectory(File userDir, String login, String scriptToExecute){
		if ((!userDir.isDirectory() || !userDir.exists()))
			executeCommandLine(scriptToExecute,login);
		
	}

	private String executeCommandLine(String cmd, String login){
		log.debug("executing command "+cmd+" "+login);
		Process process = null;
		String lastline = "";
		try {
			
			ProcessBuilder pb = new ProcessBuilder(cmd, login);
			process = pb.start();
			
			try {
				process.waitFor();
			} catch (InterruptedException e) {
				log.warn("interrupt Exception on process",e);
			}

			BufferedReader br = new BufferedReader(new InputStreamReader(process.getErrorStream()));
			String line = br.readLine();
			while (line!=null){
				lastline += line;
				line = br.readLine();
			}
		} catch (IOException e) {
			log.error("error executing command line",e);
		}
		log.debug("command result line is "+lastline);
		return lastline;
	}

	private boolean writeFile(Info info, File pathToFile){
		log.debug("writing config file");
		StringBuffer sb = new StringBuffer();
		sb.append(info.getTableName()+";");
		sb.append(info.getUserTableName()+";");

		sb.append(info.getFields());
		if (!info.getFields().endsWith(";"))
			sb.append(";");
		sb.append(info.getQueryColumns());
		if (!info.getQueryColumns().endsWith(";"))
			sb.append(";");
		sb.append(info.getDatabase().getDatabaseAddress()+";");
		sb.append(info.getDatabase().getDatabaseName()+";");
		sb.append(info.getDatabase().getDatabaseUsername()+";");
		sb.append(info.getDatabase().getDatabasePassword()+"\n");

		try{
			FileWriter fw = new FileWriter(pathToFile,false);
			fw.write(sb.toString());
			fw.close();
			log.debug("file written");
		}catch(Exception e){
			log.error("error writing config file",e);
			return false;
		}
		return true;
	}
}