package org.embulk.input.filesplit;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.net.URISyntaxException;
import java.util.Arrays;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.embulk.EmbulkService;
import org.embulk.config.ConfigLoader;
import org.embulk.config.ConfigSource;
import org.embulk.exec.ExecutionResult;
import org.embulk.exec.LocalExecutor;
import org.embulk.plugin.InjectedPluginSource;
import org.embulk.spi.ExecSession;

import com.google.inject.Binder;
import com.google.inject.Injector;
import com.google.inject.Module;

public class EmbulkPluginTester {
	
	private final Class<?> iface;
	private final String name;
	private final Class<?> impl;
	
	
	public EmbulkPluginTester(Class<?> iface, String name, Class<?> impl) 
	{
		this.iface = iface;
		this.name = name;
		this.impl = impl;
	}

	public void run(String ymlPath) throws Exception 
	{
		EmbulkService service = new EmbulkService(new EmptyConfigSource()) {
			protected Iterable<? extends Module> getAdditionalModules(ConfigSource systemConfig)
			{
				return Arrays.asList(new Module()
				{
					@Override
					public void configure(Binder binder)
					{
						InjectedPluginSource.registerPluginTo(binder, iface, name, impl);
					}
				});
			}
		};
		Injector injector = service.getInjector();
		ConfigSource config = injector.getInstance(ConfigLoader.class).fromYamlFile(convert(ymlPath));
		ExecSession session = new ExecSession(injector, config);
        LocalExecutor executor = injector.getInstance(LocalExecutor.class);
        ExecutionResult result = executor.run(session, config);
        System.out.println(result);
	}

	private File convert(String yml) {
		try {
			File rootPath = new File(EmbulkPluginTester.class.getResource("/resource.txt").toURI()).getParentFile();
			File ymlPath = new File(EmbulkPluginTester.class.getResource(yml).toURI());
			File tempYmlPath = new File(ymlPath.getParentFile(), "temp-" + ymlPath.getName());
			Pattern pathPrefixPattern = Pattern.compile("^ *path(_prefix)?: '(.*)'$");
			try (BufferedReader reader = new BufferedReader(new FileReader(ymlPath))) {
				try (BufferedWriter writer = new BufferedWriter(new FileWriter(tempYmlPath))) {
					String line;
					while ((line = reader.readLine()) != null) {
						Matcher matcher = pathPrefixPattern.matcher(line);
						if (matcher.matches()) {
							int group = 2;
							writer.write(line.substring(0, matcher.start(group)));
							writer.write(new File(rootPath, matcher.group(group)).getAbsolutePath());
							writer.write(line.substring(matcher.end(group)));
						} else {
							writer.write(line);
						}
						writer.newLine();
					}
				}
			}
			return tempYmlPath.getAbsoluteFile();
			
		} catch (IOException e) {
			throw new RuntimeException(e);
		} catch (URISyntaxException e) {
			throw new RuntimeException(e);
		}
	}
	
}