package pt.ist.renderers.servlets.rest;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

import javax.annotation.processing.AbstractProcessor;
import javax.annotation.processing.RoundEnvironment;
import javax.annotation.processing.SupportedAnnotationTypes;
import javax.annotation.processing.SupportedSourceVersion;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.Element;
import javax.lang.model.element.TypeElement;

import pt.utl.ist.fenix.tools.util.FileUtils;

@SupportedSourceVersion(SourceVersion.RELEASE_6)
@SupportedAnnotationTypes({ "pt.ist.fenixWebFramework.servlets.rest.Path" })
public class RestAnnotationProcessor extends AbstractProcessor {

    static final String LOG_FILENAME = ".restAnnotationLog";
    public static final String ENTRY_SEPERATOR = "\n";
    public static final String LINE_SEPERATOR = "\t";

    @Override
    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {

	final Map<String, String> resources = new HashMap<String, String>();

	final File file = new File(LOG_FILENAME);
	if (file.exists()) {
	    try {
		final String contents = FileUtils.readFile(LOG_FILENAME);
		for (final String line : contents.split(ENTRY_SEPERATOR)) {
		    String[] values = line.split(LINE_SEPERATOR);
		    if (values.length == 2) {
			resources.put(values[0], values[1]);
		    }
		}
	    } catch (final IOException e) {
		e.printStackTrace();
	    }
	}

	Set<? extends Element> elementsAnnotatedWith = roundEnv.getElementsAnnotatedWith(Path.class);
	for (final Element element : elementsAnnotatedWith) {
	    if (element instanceof TypeElement) {
		resources.put(((TypeElement) element).getQualifiedName().toString(), element.getAnnotation(Path.class).value());
	    }
	}

	FileWriter fileWriter = null;
	try {
	    fileWriter = new FileWriter(LOG_FILENAME, true);
	    for (final Entry<String, String> entry : resources.entrySet()) {
		fileWriter.append(entry.getKey());
		fileWriter.append(LINE_SEPERATOR);
		fileWriter.append(entry.getValue());
		fileWriter.write(ENTRY_SEPERATOR);

	    }
	} catch (final IOException e) {
	    e.printStackTrace();
	} finally {
	    if (fileWriter != null) {
		try {
		    fileWriter.close();
		} catch (final IOException e) {
		    e.printStackTrace();
		}
	    }
	}

	return true;
    }

}