FileSystem.java

package com.elsealabs.xshot.file;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.util.ArrayList;
import java.util.HashMap;

import com.elsea.stone.property.PropertyPool;
import com.elsea.stone.property.PropertyPoolReader;
import com.elsea.stone.property.PropertyPoolWriter;

/**
 * FileSystem
 * 
 * Holds information about locations of important directories  and
 * files relevant to the program. It also holds helper methods for
 * directory and file repair and first time setup.
 * 
 * @author Connor M. Elsea
 */
public class FileSystem {
	
	public static enum OS
	{
		WINDOWS, OSX, LINUX
	}
	
	private OS      osType;
	private String  osName;
	private String  userPath;
	
	/**	
	 * The paths that can be returned by this class' accessor  methods
	 * are bound by the PATH enumeration to eliminate the use of magic
	 * String for retrieving paths from the hash map.
	 */
	public static enum PATH
	{
		PROGRAM_DIR,
		STONE_FILE,
		SAVE_DEFAULT_DIR
	}
	
	private HashMap<String, File> files;
	
	private File location_programDir;
	private File location_stoneFile;
	private File location_saveDefaultDir;
	
	
	/**
	 * When a file system check is performed, issues that are  found
	 * are added to the array list of issues. The type of the issues
	 * are bound by the ISSUE enumeration.
	 */
	public static enum ISSUE
	{
		MISSING_PROGRAM_DIR,
		MISSING_SAVE_DIR,
		MISSING_STONE,
		MALFORMED_STONE
	}
	
	private ArrayList<ISSUE> issues;
	
	/**
	 * Various data held by the File System object.
	 */
	
	private PropertyPool pool;
	
	/**
	 * Runs all the needed methods for starting up the program and
	 * loading the initial data.
	 */
	public void run()
	{
		loadPaths();
		check();
		fix();
	}
	
	/**
	 * Checks for various problems and if they are present,  their
	 * corresponding issue to the arrray list. Loads in Stone data
	 * if it is present and not malformed.
	 */
	public void check()
	{
		System.out.println("File System: Checking for issues.");
		
		if (issues == null) issues = new ArrayList<ISSUE>();
		else issues.clear();
		
		if (!getPath(PATH.PROGRAM_DIR).exists())
		{
			issues.add(ISSUE.MISSING_PROGRAM_DIR);
		}
		
		if (!getPath(PATH.SAVE_DEFAULT_DIR).exists())
		{
			issues.add(ISSUE.MISSING_SAVE_DIR);
		}
		
		if (!getPath(PATH.STONE_FILE).exists())
		{
			issues.add(ISSUE.MISSING_STONE);
		}
		else
		{
			PropertyPoolReader reader = new PropertyPoolReader();
			
			// reader.read(...) returns a boolean indicating whether or not the reader
			// read in the data correctly. If the data was read 	in corerctly, set  the
			// read in pool as a member of the File  System  class. If  not,  add  the
			// malformed stone issue to the issue array list.
			
			if (reader.read(getPath(PATH.STONE_FILE)))
			{
				pool = reader.getPropertyPool();
				
				if (pool.search().getGroup("locations") == null)
				{
					issues.add(ISSUE.MISSING_STONE);
				}
			}
			else
			{
				issues.add(ISSUE.MALFORMED_STONE);
			}
		}
	}
	
	/**
	 * Fixes errors if they are present.
	 */
	public void fix()
	{
		System.out.println("File System: Attempting to fix any issues");
		
		if (!issues.isEmpty())
		{
			if (issues.contains(ISSUE.MISSING_PROGRAM_DIR))
			{
				fix_MissingProgramDir();
			}
			
			if (issues.contains(ISSUE.MISSING_SAVE_DIR))
			{
				fix_MissingSaveDir();
			}
			
			if (issues.contains(ISSUE.MISSING_STONE))
			{
				fix_MissingStone();
			}
			
			if (issues.contains(ISSUE.MALFORMED_STONE))
			{
				fix_MalformedStone();
			}
			
			issues.clear();
		}
	}
	
	public void fix_MissingProgramDir()
	{
		System.out.println("Resolve: Attempting to fix missing program directory.");
		
		try
		{
			
			Files.createDirectories(getPath(PATH.PROGRAM_DIR).toPath());
		}
		catch (IOException e)
		{
			e.printStackTrace();
		}
	}
	
	public void fix_MissingSaveDir()
	{
		System.out.println("Resolve: Attempting to fix missing save directory.");
		
		// TODO: Ask user for new save directory.
		System.err.println("Error: Missing Save Directory. Cannot fix in current build.");
	}
	
	public void fix_MissingStone()
	{
		System.out.println("Resolve: Attempting to fix missing Stone file.");
		
		// Get default path generated by File System and put it into
		// the Stone template. They can change it in the future, but
		// this is just setting up defaults.
		
		String defaultSave =  getPath(FileSystem.PATH.SAVE_DEFAULT_DIR).getAbsolutePath();
		
		// Create the Property Pool and fill it with the defaults.
					
		pool = new PropertyPool();
		
		pool
			.group("file")
				.group("locations")
				
					.group("location")
						.property("name", "Pictures")
						.property("path", defaultSave)
						.property("default", "true")
					.end()
					
				.end()
			.end()
			.group("actions")
				.property("autoCopy", "true")
			.end()
			;
		
		// Write the Property Pool to the file system
		
		PropertyPoolWriter writer = new PropertyPoolWriter();
		
		if (writer.write(pool, getPath(PATH.STONE_FILE)))
		{
			System.out.println("Resolve: Wrote Stone file correctly");
		}
		else
		{
			System.err.println("Fatal Error: Failed to write Stone file.");
		}
	}
	
	public void fix_MalformedStone()
	{
		System.out.println("Resolve: Attempting to fix malformed stone file.");
		System.err.println("Errror: Cannot fix malformed stone file.");
	}
	
	/**
	 * Determine the operating system and generate the paths needed by this
	 * program, some of which differ between each operating system.
	 */
	public void loadPaths()
	{
		System.out.println("File System: Determining paths.");
		
		files = new HashMap<String, File>();
		
		osName   = System.getProperty("os.name").toLowerCase();
		userPath = System.getProperty("user.home");
		
		if (osName.contains("windows"))
		{
			osType = OS.WINDOWS;
			location_programDir     = new File(System.getenv("APPDATA") + "\\Capshot");
			location_saveDefaultDir = new File(userPath + "\\Pictures");
			location_stoneFile      = new File(System.getenv("APPDATA") + "\\Capshot\\stone.xml");
		}
		else if (osName.contains("mac"))
		{
			osType = OS.OSX;
			location_programDir = new File(getUserPath() + "/Library/Application Support/Capshot");
		}
		else if (osName.contains("nix") || osName.contains("nux"))
		{
			osType = OS.LINUX;
			location_programDir = new File(getUserPath() + "/Capshot");
		}
		else
		{
			osType = OS.WINDOWS;
			System.err.println("Error: Could not determine OS from os.name = \"" + osName + "\"");
			System.err.println("Warning: Defaulting OS to WINDOWS.");
		}
		
		System.out.println("File System: Program directory " + location_programDir.getAbsolutePath());
		
		location_stoneFile  = new File(location_programDir.getAbsolutePath() + "\\settings.xml");
	}
	
	/**
	 * Return the File object for the specified pre-defined location
	 * 
	 * @param path The pre-defined location
	 * @return The file object for the specified pre-defined location
	 */
	public File getPath(PATH path)
	{
		switch (path)
		{
			case PROGRAM_DIR:
				return location_programDir;
				
			case STONE_FILE:				
				return location_stoneFile;
			
			case SAVE_DEFAULT_DIR:
				return location_saveDefaultDir;
			
			default:
				throw new IllegalArgumentException();
		}
	}
	
	public OS getOsType() {
		return osType;
	}
	
	public String getOsName() {
		return osName;
	}
	
	public String getUserPath() {
		return userPath;
	}

}