package application.parsing;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.nio.file.Files;

import application.helpers.Utils;
import application.helpers.wrappers.WrappedException;
import application.res.Text;

/**
 * This class wraps a file together with its writer and readable name together,
 * so the writer can be written on repeatedly without having to be opened each
 * and every time.
 * 
 * @author Bianca
 *
 */

public class FileWrapper
{
	/**
	 * The file to be wrapped
	 */
	private File file;
	/**
	 * The filename in a readable format so it can be displayed to the user.
	 */
	private String readableFileName;
	/**
	 * A writer for the file
	 */
	private BufferedWriter bout;

	/**
	 * Creates a file in temp directory for this filename and creates the writer.
	 * 
	 * @param filename            Exact filename ending
	 * @param readableFilename    First part of the readable name
	 * @param readableSubFilename Second part of the readable name
	 * @throws WrappedException If there was an error creating the file or the
	 *                          writer
	 */
	private FileWrapper(String filename, String readableFilename, String readableSubFilename) throws WrappedException
	{
		try
		{
			file = Files.createTempFile("health_data", "__" + filename).toFile();
			readableFileName = createReadableFileName(readableFilename, readableSubFilename);
			file.deleteOnExit();
			bout = new BufferedWriter(new FileWriter(file, true));
		}
		catch (IOException e)
		{
			throw new WrappedException(null, Text.E_CREATE_TEMP_FILES);
		}
	}

	/**
	 * Creates a file in temp directory for this filename and creates the writer.
	 * 
	 * @param filename         Exact filename ending
	 * @param readableFilename Readable name
	 * @throws WrappedException If there was an error creating the file or the
	 *                          writer
	 */
	public FileWrapper(String filename, String readableFilename) throws WrappedException
	{
		this(filename, readableFilename, null);
	}

	/**
	 * Creates a file in temp directory for this filename and creates the writer.
	 * The header will be written with the given header coloumns.
	 * 
	 * @param filename            Exact filename ending
	 * @param readableFilename    First part of the readable name
	 * @param readableSubFilename Second part of the readable name
	 * @param headerColoums       The header coloumn names
	 * @throws WrappedException If there was an error creating the file or the
	 *                          writer
	 */
	public FileWrapper(String filename, String readableFilename, String readableSubFilename, String[] headerColoums)
			throws WrappedException
	{
		this(filename, readableFilename, readableSubFilename);
		try
		{
			writeHeaderColumn(headerColoums, true);
			bout.newLine();
		}
		catch (IOException e)
		{
			throw new WrappedException(null, Text.E_CREATE_TEMP_FILES);
		}
	}

	/**
	 * Combines the two parts of the readable filename into on.
	 * 
	 * @param partOne The first (main) part of the filename.
	 * @param partTwo The second (additional) part of the filename.
	 * @return The described value.
	 */
	public static String createReadableFileName(String partOne, String partTwo)
	{
		if (partTwo == null)
		{
			return String.format(Text.F_FILE_DESC, partOne, "");
		}
		return String.format(Text.F_FILE_DESC, partOne, partTwo);
	}

	/**
	 * Creates a readable filename.
	 * 
	 * @param name The intended filename.
	 * @return The described value.
	 */
	public static String createReadableFileName(String name)
	{
		return createReadableFileName(name, null);
	}

	/**
	 * Writes the header column in the files (names of attributes and sub attributes
	 * (in lists))
	 * 
	 * @param attributes names of the attributes
	 * @param top        attributes can be nested. If this is {@code True}, then
	 *                   this is the top level attribute. If this is {@code False}
	 *                   than it's a sub attribute.
	 * @throws IOException if there was an error writing
	 */
	private void writeHeaderColumn(String[] attributes, boolean top) throws IOException
	{
		for (int i = 0; i < attributes.length; i++)
		{
			// write attributeName
			bout.write(attributes[i]);
			// in case of sub attributes write sested elements
			if (attributes[i].equalsIgnoreCase(Text.TAG_NAME_META_DATA_ENTRY))
			{
				bout.write("[[");
				writeHeaderColumn(Utils.META_DATA_ATTR, false);
				bout.write("]*]");
			}
			if (attributes[i].equalsIgnoreCase(Text.TAG_NAME_WORKOUT_EVENT))
			{
				bout.write("[[");
				writeHeaderColumn(Utils.WORKOUT_EVENT_ATTR, false);
				bout.write("]*]");
			}
			if (attributes[i].equalsIgnoreCase(Text.TAG_NAME_WORKOUT_ROUTE))
			{
				bout.write("[[");
				writeHeaderColumn(Utils.WORKOUT_ROUTE_ATTR, false);
				bout.write("]*]");
			}
			if (attributes[i].equalsIgnoreCase(Text.TAG_NAME_HR_LIST))
			{
				bout.write("[[");
				writeHeaderColumn(Utils.HR_LIST_ATTR, false);
				bout.write("]*]");
			}
			if (attributes[i].equalsIgnoreCase(Text.TAG_NAME_IB_PER_MINUTES))
			{
				bout.write("[[");
				writeHeaderColumn(Utils.IB_PER_MINUTES_ATTR, false);
				bout.write("]*]");
			}
			//Elements are separated with ';' on top level and with ',' on all other levels
			if (i < attributes.length - 1)
			{
				if (top)
				{
					bout.write(";");
				}
				else
				{
					bout.write(",");
				}
			}
		}
	}

	
	/**
	 * Returns the writer for the file.
	 * @return the described value.
	 */
	public BufferedWriter getBufferedWriter()
	{
		return bout;
	}

	/**
	 * Returns the file as an object.
	 * @return The described value.
	 */
	public File getFile()
	{
		return file;
	}

	/**
	 * Returns the readable filename.
	 * @return The described value.
	 */
	public String getReadableFilename()
	{
		return readableFileName;
	}

}