/*
 * Hedgewars for Android. An Android port of Hedgewars, a free turn based strategy game
 * Copyright (c) 2011-2012 Richard Deurwaarder <xeli@xelification.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */


package org.hedgewars.hedgeroid;

import java.io.Closeable;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;

import android.annotation.TargetApi;
import android.app.Application;
import android.content.Context;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.os.Build;
import android.os.Environment;
import android.util.Log;

public class Utils {
	private static final String ROOT_DIR = "Data";
	private static final String TAG = "org.hedgewars.hedgeroid";

	/**
	 * @return true if the data path is currently available. However, it can vanish at any time so
	 * normally you should just try to use it and rely on the exceptions.
	 */
	public static boolean isDataPathAvailable() {
		return Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState());
	}
	
	/**
	 * get the path to which we should download all the data files
	 * @param c context 
	 * @return The directory
	 * @throws FileNotFoundException if external storage is not avaliable at the moment
	 */
	public static File getCachePath(Context c) throws FileNotFoundException {
		File cachePath = null;
		if(Build.VERSION.SDK_INT < 8){//8 == Build.VERSION_CODES.FROYO
			cachePath = PreFroyoSDCardDir.getDownloadPath(c);
		} else {
			cachePath = FroyoSDCardDir.getDownloadPath(c);
		}
		if(cachePath==null) {
			throw new FileNotFoundException("External storage is currently unavailable");
		} else {
			return cachePath;
		}
	}

	public static File getDataPathFile(Context c) throws FileNotFoundException {
		return new File(getCachePath(c), ROOT_DIR);
	}
	
	// TODO Several callers are unaware that this may fail, so it throws an RTE now.
	// Should be handled better though.
	@Deprecated
	public static String getDataPath(Context c) {
		try {
			return getDataPathFile(c).getAbsolutePath()+"/";
		} catch(FileNotFoundException e) {
			throw new RuntimeException(e);
		}
	}

	@TargetApi(8)
	private static class FroyoSDCardDir{
		public static File getDownloadPath(Context c){
			return c.getExternalCacheDir();
		}
	}

	private static class PreFroyoSDCardDir{
		public static File getDownloadPath(Context c){
			if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
				File extStorageDir = Environment.getExternalStorageDirectory();
				if(extStorageDir != null) {
					return new File(extStorageDir, "Hedgewars");
				}
			}
			return null;
		}
	}

	/**
	 * Get files from dirName, dir name is relative to {@link getDownloadPath}
	 * @param dirName
	 * @param c context
	 * @return string of files
	 */
	public static String[] getFileNamesFromRelativeDir(Context c, String dirName){
		String prefix = getDataPath(c);
		File f = new File(prefix + dirName);

		if(f.exists() && f.isDirectory()) return f.list();
		else{

			Log.e("Utils::", "Couldn't find dir: " + dirName);
			return new String[0];
		}
	}

	/**
	 * Return a File array with all the files from dirName
	 * @param c
	 * @param dirName
	 * @return
	 */
	public static File[] getFilesFromRelativeDir(Context c, String dirName){
		String prefix = getDataPath(c);
		File f = new File(prefix + dirName);

		if(f.exists() && f.isDirectory()) return f.listFiles();
		else {
			Log.e("Utils::", "Dir not found: " + dirName);
			return new File[0];
		}
	}

	/**
	 * Checks if this directory has a file with suffix suffix
	 * @param f - directory
	 * @return
	 */
	public static boolean hasFileWithSuffix(File f, String suffix){
		if(f.isDirectory()){
			for(String s : f.list()){
				if(s.endsWith(suffix)) return true;
			}
			return false;
		}else{
			return false;
		}
	}

	/**
	 * Gives back all dirs which contain a file with suffix fileSuffix
	 * @param c
	 * @param path
	 * @param fileSuffix
	 * @return
	 */
	public static List<String> getDirsWithFileSuffix(Context c, String path, String fileSuffix){
		File[] files = getFilesFromRelativeDir(c,path);
		ArrayList<String> ret = new ArrayList<String>();

		for(File f : files){
			if(hasFileWithSuffix(f, fileSuffix)) ret.add(f.getName());
		}
		return ret;
	}

	/**
	 * Get all files from directory dir which have the given suffix
	 * @param c
	 * @param dir
	 * @param suffix
	 * @param removeSuffix
	 * @return
	 */
	public static ArrayList<String> getFilesFromDirWithSuffix(Context c, String dir, String suffix, boolean removeSuffix){
		String[] files = Utils.getFileNamesFromRelativeDir(c, dir);
		ArrayList<String> ret = new ArrayList<String>();
		for(String s : files){
			if(s.endsWith(suffix)){
				if(removeSuffix) ret.add(s.substring(0, s.length()-suffix.length()));
				else ret.add(s);
			}
		}
		return ret;
	}

	/**
	 * Close a resource (possibly null), ignoring any IOException.
	 */
	public static void closeQuietly(Closeable c) {
		if(c!=null) {
			try {
				c.close();
			} catch(IOException e) {
				Log.w(TAG, e);
			}
		}
	}
	
	/**
	 * Write all data from the input stream to the file, creating or overwriting it.
	 * The input stream will be closed.
	 * 
	 * @throws IOException
	 */
	public static void writeStreamToFile(InputStream is, File file) throws IOException {
		OutputStream os = null;
		byte[] buffer = new byte[8192];
		try {
			os = new FileOutputStream(file);
			int size;
			while((size=is.read(buffer)) != -1) {
				os.write(buffer, 0, size);
			}
			os.close(); // Important to close this non-quietly, in case of exceptions when flushing
		} finally {
			Utils.closeQuietly(is);
			Utils.closeQuietly(os);
		}
	}
	
	/**
	 * Moves resources pointed to by sourceResId (from @res/raw/) to the app's private data directory
	 * @param c
	 * @param sourceResId
	 * @param directory
	 */
	public static void resRawToFilesDir(Context c, int sourceResId, String directory) throws IOException {
		File targetDir = new File(c.getFilesDir(), directory);
		targetDir.mkdirs();

		//Get an array with the resource files ID
		Resources resources = c.getResources();
		TypedArray ta = resources.obtainTypedArray(sourceResId);
		for(int i = 0; i < ta.length(); i++){
			int resId =  ta.getResourceId(i, 0);
			String fileName = resources.getResourceEntryName(resId);
			File f = new File(targetDir, fileName);
			writeStreamToFile(resources.openRawResource(resId), f);
		}
	}
	
	/**
	 * Crashing - at least it's better than ignoring errors.
	 */
	public static void assertZero(int value, String text) {
		if(value != 0) {
			throw new RuntimeException("Result is not zero: " + text);
		}
	}
}