package org.simantics.document;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLDecoder;
import java.nio.charset.Charset;
import java.nio.file.Files;

import org.eclipse.core.runtime.FileLocator;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;
import org.osgi.framework.BundleContext;
import org.simantics.Simantics;

public class PhantomJSDriver {

	public static File fileRef(String fileName) throws IOException {
		
		BundleContext context = Activator.getContext();
        IPath path = new Path("/" + fileName);
        URL libURL = FileLocator.find(context.getBundle(), path, null);
        URL fileURL = FileLocator.toFileURL(libURL);
        return new File(URLDecoder.decode(fileURL.getPath(), "UTF-8"));
        
	}
	
	public static String printCommand(String margin, String url, String outFile) throws IOException {

		try {
			File f = fileRef("print.js");
			String template = new String(Files.readAllBytes(f.toPath()));
			template = template.replace("%%url", url);
			template = template.replace("%%margin", margin);
			template = template.replace("%%file", outFile.replace("\\", "/"));
			return template;
		} catch (IOException e) {
			return null;
		}
		
	}
	
	public static void print(String html, DocumentSettings settings, File output) throws IOException {
		
    	File htmlFile = Simantics.getTempfile("PhantomJSDriver", "html");
		Files.write(htmlFile.toPath(), html.getBytes(Charset.forName("UTF-8")));
		
		String browserUrl = htmlFile.toURI().toURL().toString();
		
    	File script = Simantics.getTempfile("PhantomJSDriver", "script");
    	
    	String margin = "{left:\"" + settings.marginLeft + "mm\", right:\"" + settings.marginRight + "mm\", top:\"" + settings.marginTop + "mm\", bottom:\"" + settings.marginBottom + "mm\"}";
    	
		String printCommand = PhantomJSDriver.printCommand(margin, browserUrl, output.getAbsolutePath());
    	
    	Files.write(script.toPath(), printCommand.getBytes());
		PhantomJSDriver.execute(script);

	}
	
	public static boolean execute(File javascript) {
		
		try {
			
	        File filePath = fileRef("phantomjs.exe");
	        
			String[] args = { filePath.getAbsolutePath(),
					javascript.getAbsolutePath()					
			};
			Process process = new ProcessBuilder(args).start();
			try {
				InputStream input = process.getInputStream();
				InputStreamReader reader = new InputStreamReader(input);
				//StringBuilder sb = new StringBuilder();
				while (true) {
					try {
						while (reader.ready()) {
							int r = reader.read();
						}
						
						int error = process.exitValue();
						
						reader.close();
						return error == 0;
						
					} catch (IllegalThreadStateException e) {
						Thread.sleep(100);
					}
				}
			} finally {
				process.destroy();
			}
		} catch(IOException e) {
			e.printStackTrace();
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
		return false;

	}
	
}