/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.nativescript.widgets.image;

import android.annotation.TargetApi;
import android.content.ContentResolver;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.net.Uri;
import android.os.Build;
import android.os.ParcelFileDescriptor;
import android.util.Log;
import android.util.TypedValue;

import androidx.exifinterface.media.ExifInterface;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;

/**
 * A simple subclass of {@link Worker} that fetch and resize images from a file, resource or URL.
 */
public class Fetcher extends Worker {
	private static final int HTTP_CACHE_SIZE = 10 * 1024 * 1024; // 10MB
	private static final String HTTP_CACHE_DIR = "http";
	private static final int IO_BUFFER_SIZE = 8 * 1024;

	private static int mDeviceWidthPixels;
	private static int mDeviceHeightPixels;

	private final File mHttpCacheDir;
	private DiskLruCache mHttpDiskCache;
	private boolean mHttpDiskCacheStarting = true;
	private final Object mHttpDiskCacheLock = new Object();
	private static final int DISK_CACHE_INDEX = 0;

	private final String mPackageName;
	private static Fetcher instance;

	public static Fetcher getInstance(Context context) {
		if (instance == null) {
			instance = new Fetcher(context);
		}

		return instance;
	}

	/**
	 * Initialize providing a target image width and height for the processing images.
	 *
	 * @param context
	 */
	private Fetcher(Context context) {
		super(context);
		mHttpCacheDir = Cache.getDiskCacheDir(context, HTTP_CACHE_DIR);
		mPackageName = context.getPackageName();
		mDeviceWidthPixels = context.getResources().getDisplayMetrics().widthPixels;
		mDeviceHeightPixels = context.getResources().getDisplayMetrics().heightPixels;
	}

	@Override
	protected void initDiskCacheInternal() {
		if (!mHttpCacheDir.exists()) {
			mHttpCacheDir.mkdirs();
		}
		synchronized (mHttpDiskCacheLock) {
			if (Cache.getUsableSpace(mHttpCacheDir) > HTTP_CACHE_SIZE) {
				try {
					mHttpDiskCache = DiskLruCache.open(mHttpCacheDir, 1, 1, HTTP_CACHE_SIZE);
					if (debuggable > 0) {
						Log.v(TAG, "HTTP cache initialized");
					}
				} catch (IOException e) {
					mHttpDiskCache = null;
				}
			}
			mHttpDiskCacheStarting = false;
			mHttpDiskCacheLock.notifyAll();
		}
	}

	@Override
	protected void clearCacheInternal() {
		super.clearCacheInternal();
		synchronized (mHttpDiskCacheLock) {
			if (mHttpDiskCache != null && !mHttpDiskCache.isClosed()) {
				try {
					mHttpDiskCache.delete();
					if (debuggable > 0) {
						Log.v(TAG, "HTTP cache cleared");
					}
				} catch (IOException e) {
					Log.e(TAG, "clearCacheInternal - " + e);
				}
				mHttpDiskCache = null;
				mHttpDiskCacheStarting = true;
			}
		}
	}

	@Override
	protected void flushCacheInternal() {
		synchronized (mHttpDiskCacheLock) {
			if (mHttpDiskCache != null) {
				try {
					mHttpDiskCache.flush();
					if (debuggable > 0) {
						Log.v(TAG, "HTTP cache flushed");
					}
				} catch (IOException e) {
					Log.e(TAG, "flush - " + e);
				}
			}
		}
	}

	@Override
	protected void closeCacheInternal() {
		synchronized (mHttpDiskCacheLock) {
			if (mHttpDiskCache != null) {
				try {
					if (!mHttpDiskCache.isClosed()) {
						mHttpDiskCache.close();
						mHttpDiskCache = null;
						if (debuggable > 0) {
							Log.v(TAG, "HTTP cache closed");
						}
					}
				} catch (IOException e) {
					Log.e(TAG, "closeCacheInternal - " + e);
				}
			}
		}
	}

	/**
	 * The main process method, which will be called by the Worker in the AsyncTask background
	 * thread.
	 *
	 * @param data The data to load the bitmap, in this case, a regular http URL
	 * @return The downloaded and resized bitmap
	 */
	private Bitmap processHttp(String data, int decodeWidth, int decodeHeight, boolean keepAspectRatio) {
		final String key = Cache.hashKeyForDisk(data);
		FileDescriptor fileDescriptor = null;
		FileInputStream fileInputStream = null;
		DiskLruCache.Snapshot snapshot;
		synchronized (mHttpDiskCacheLock) {
			// Wait for disk cache to initialize
			while (mHttpDiskCacheStarting) {
				try {
					mHttpDiskCacheLock.wait();
				} catch (InterruptedException e) {
				}
			}

			if (mHttpDiskCache != null) {
				try {
					snapshot = mHttpDiskCache.get(key);
					if (snapshot == null) {
						if (debuggable > 0) {
							Log.v(TAG, "processBitmap, not found in http cache, downloading...");
						}
						DiskLruCache.Editor editor = mHttpDiskCache.edit(key);
						if (editor != null) {
							if (downloadUrlToStream(data, editor.newOutputStream(DISK_CACHE_INDEX))) {
								editor.commit();
							} else {
								editor.abort();
							}
						}
						snapshot = mHttpDiskCache.get(key);
					}
					if (snapshot != null) {
						fileInputStream = (FileInputStream) snapshot.getInputStream(DISK_CACHE_INDEX);
						fileDescriptor = fileInputStream.getFD();
					}
				} catch (IOException e) {
					Log.e(TAG, "processHttp - " + e);
				} catch (IllegalStateException e) {
					Log.e(TAG, "processHttp - " + e);
				} finally {
					if (fileDescriptor == null && fileInputStream != null) {
						try {
							fileInputStream.close();
						} catch (IOException e) {
						}
					}
				}
			}
		}

		Bitmap bitmap = null;
		if (fileDescriptor != null) {
			bitmap = decodeSampledBitmapFromDescriptor(fileDescriptor, decodeWidth, decodeHeight, keepAspectRatio,
				getCache());
		}
		if (fileInputStream != null) {
			try {
				fileInputStream.close();
			} catch (IOException e) {
			}
		}
		return bitmap;
	}

	private Bitmap processHttpNoCache(String data, int decodeWidth, int decodeHeight, boolean keepAspectRatio) {
		ByteArrayOutputStreamInternal outputStream = null;
		Bitmap bitmap = null;

		try {
			outputStream = new ByteArrayOutputStreamInternal();
			if (downloadUrlToStream(data, outputStream)) {
				bitmap = decodeSampledBitmapFromByteArray(outputStream.getBuffer(), decodeWidth, decodeHeight,
					keepAspectRatio, getCache());
			}
		} catch (IllegalStateException e) {
			Log.e(TAG, "processHttpNoCache - " + e);
		} finally {
			if (outputStream != null) {
				try {
					outputStream.close();
				} catch (IOException e) {
				}
			}
		}

		return bitmap;
	}

	@Override
	protected Bitmap processBitmap(String uri, int decodeWidth, int decodeHeight, boolean keepAspectRatio,
																 boolean useCache) {
		if (debuggable > 0) {
			Log.v(TAG, "process: " + uri);
		}
		if (uri.startsWith(CONTENT_PREFIX)) {
			return decodeSampledBitmapFromContent(uri, mResolver, decodeWidth, decodeHeight, keepAspectRatio, getCache());
		} else if (uri.startsWith(FILE_PREFIX)) {
			String filename = uri.substring(FILE_PREFIX.length());
			return decodeSampledBitmapFromFile(filename, decodeWidth, decodeHeight, keepAspectRatio, getCache());
		} else if (uri.startsWith(RESOURCE_PREFIX)) {
			String resPath = uri.substring(RESOURCE_PREFIX.length());
			int resId = mResources.getIdentifier(resPath, "drawable", mPackageName);
			if (resId > 0) {
				return decodeSampledBitmapFromResource(mResources, resId, decodeWidth, decodeHeight, keepAspectRatio,
					getCache());
			} else {
				Log.v(TAG, "Missing Image with resourceID: " + uri);
				return null;
			}
		} else {
			if (useCache && mHttpDiskCache != null) {
				return processHttp(uri, decodeWidth, decodeHeight, keepAspectRatio);
			} else {
				return processHttpNoCache(uri, decodeWidth, decodeHeight, keepAspectRatio);
			}
		}
	}

	/**
	 * Download a bitmap from a URL and write the content to an output stream.
	 *
	 * @param urlString The URL to fetch
	 * @return true if successful, false otherwise
	 */
	public boolean downloadUrlToStream(String urlString, OutputStream outputStream) {
		disableConnectionReuseIfNecessary();
		HttpURLConnection urlConnection = null;
		BufferedOutputStream out = null;
		BufferedInputStream in = null;

		try {
			final URL url = new URL(urlString);
			urlConnection = (HttpURLConnection) url.openConnection();
			in = new BufferedInputStream(urlConnection.getInputStream(), IO_BUFFER_SIZE);
			out = new BufferedOutputStream(outputStream, IO_BUFFER_SIZE);

			int b;
			while ((b = in.read()) != -1) {
				out.write(b);
			}
			return true;
		} catch (final IOException e) {
			Log.e(TAG, "Error in downloadBitmap - " + e);
		} finally {
			if (urlConnection != null) {
				urlConnection.disconnect();
			}
			try {
				if (out != null) {
					out.close();
				}
				if (in != null) {
					in.close();
				}
			} catch (final IOException e) {
			}
		}
		return false;
	}

	/**
	 * Workaround for bug pre-Froyo, see here for more info:
	 * http://android-developers.blogspot.com/2011/09/androids-http-clients.html
	 */
	public static void disableConnectionReuseIfNecessary() {
		// HTTP connection reuse which was buggy pre-froyo
		if (Build.VERSION.SDK_INT < Build.VERSION_CODES.FROYO) {
			System.setProperty("http.keepAlive", "false");
		}
	}

	private static class ByteArrayOutputStreamInternal extends ByteArrayOutputStream {
		public byte[] getBuffer() {
			return buf;
		}
	}

	/**
	 * Decode and sample down a bitmap from resources to the requested width and height.
	 *
	 * @param res       The resources object containing the image data
	 * @param resId     The resource id of the image data
	 * @param reqWidth  The requested width of the resulting bitmap
	 * @param reqHeight The requested height of the resulting bitmap
	 * @param cache     The Cache used to find candidate bitmaps for use with inBitmap
	 * @return A bitmap sampled down from the original with the same aspect ratio and dimensions
	 * that are equal to or greater than the requested width and height
	 */
	public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId, int reqWidth, int reqHeight,
																											 boolean keepAspectRatio, Cache cache) {

		// BEGIN_INCLUDE (read_bitmap_dimensions)
		// First decode with inJustDecodeBounds=true to check dimensions
		final BitmapFactory.Options options = new BitmapFactory.Options();
		options.inJustDecodeBounds = true;
		BitmapFactory.decodeResource(res, resId, options);

		options.inSampleSize = calculateInSampleSize(options.outWidth, options.outHeight, reqWidth, reqHeight);

		// END_INCLUDE (read_bitmap_dimensions)

		// If we're running on Honeycomb or newer, try to use inBitmap
		if (Utils.hasHoneycomb()) {
			addInBitmapOptions(options, cache);
		}

		// Decode bitmap with inSampleSize set
		options.inJustDecodeBounds = false;
		Bitmap bitmap = null;
		InputStream is = null;

		try {
			final TypedValue value = new TypedValue();
			is = res.openRawResource(resId, value);
			bitmap = BitmapFactory.decodeResourceStream(res, value, is, null, options);
		} catch (Exception e) {
            /*  do nothing.
                If the exception happened on open, bm will be null.
                If it happened on close, bm is still valid.
            */
		}


		if (bitmap == null) {
			// throw new IllegalArgumentException("Problem decoding into existing bitmap");
			return null;
		}

		ExifInterface ei = getExifInterface(is);

		return scaleAndRotateBitmap(bitmap, ei, reqWidth, reqHeight, keepAspectRatio);
	}

	@TargetApi(Build.VERSION_CODES.N)
	private static ExifInterface getExifInterface(InputStream is) {
		ExifInterface ei = null;
		try {
			if (Utils.hasN()) {
				ei = new ExifInterface(is);
			}
		} catch (final Exception e) {
			Log.e(TAG, "Error in reading bitmap - " + e);
		} finally {
			if (is != null) {
				try {
					is.close();
				} catch (IOException e) {
				}
			}
		}

		return ei;
	}

	@TargetApi(Build.VERSION_CODES.N)
	private static ExifInterface getExifInterface(FileDescriptor fd) {
		ExifInterface ei = null;
		try {
			if (Utils.hasN()) {
				ei = new ExifInterface(fd);
			}
		} catch (final Exception e) {
			Log.e(TAG, "Error in reading bitmap - " + e);
		}

		return ei;
	}

	private static ExifInterface getExifInterface(String fileName) {
		ExifInterface ei = null;
		try {
			ei = new ExifInterface(fileName);
		} catch (final Exception e) {
			Log.e(TAG, "Error in reading bitmap - " + e);
		}

		return ei;
	}

	/**
	 * Decode and sample down a bitmap from a file to the requested width and height.
	 *
	 * @param fileName  The full path of the file to decode
	 * @param reqWidth  The requested width of the resulting bitmap
	 * @param reqHeight The requested height of the resulting bitmap
	 * @param cache     The Cache used to find candidate bitmaps for use with inBitmap
	 * @return A bitmap sampled down from the original with the same aspect ratio and dimensions
	 * that are equal to or greater than the requested width and height
	 */
	public static Bitmap decodeSampledBitmapFromFile(String fileName, int reqWidth, int reqHeight,
																									 boolean keepAspectRatio, Cache cache) {

		// First decode with inJustDecodeBounds=true to check dimensions
		final BitmapFactory.Options options = new BitmapFactory.Options();
		options.inJustDecodeBounds = true;
		BitmapFactory.decodeFile(fileName, options);

		options.inSampleSize = calculateInSampleSize(options.outWidth, options.outHeight, reqWidth, reqHeight);

		// If we're running on Honeycomb or newer, try to use inBitmap
		if (Utils.hasHoneycomb()) {
			addInBitmapOptions(options, cache);
		}

		// Decode bitmap with inSampleSize set
		options.inJustDecodeBounds = false;

		final Bitmap bitmap = BitmapFactory.decodeFile(fileName, options);
		ExifInterface ei = getExifInterface(fileName);

		return scaleAndRotateBitmap(bitmap, ei, reqWidth, reqHeight, keepAspectRatio);
	}

	private static void closePfd(ParcelFileDescriptor pfd) {
		if (pfd != null) {
			try {
				pfd.close();
			} catch (IOException ignored) {
			}
		}
	}

	/**
	 * Decode and sample down a bitmap from a file to the requested width and height.
	 *
	 * @param content   The content uri of the file to decode
	 * @param reqWidth  The requested width of the resulting bitmap
	 * @param reqHeight The requested height of the resulting bitmap
	 * @param cache     The Cache used to find candidate bitmaps for use with inBitmap
	 * @return A bitmap sampled down from the original with the same aspect ratio and dimensions
	 * that are equal to or greater than the requested width and height
	 */
	public static Bitmap decodeSampledBitmapFromContent(String content, ContentResolver resolver, int reqWidth, int reqHeight,
																											boolean keepAspectRatio, Cache cache) {

		// First decode with inJustDecodeBounds=true to check dimensions
		final BitmapFactory.Options options = new BitmapFactory.Options();
		options.inJustDecodeBounds = true;


		Uri uri = android.net.Uri.parse(content);
		ParcelFileDescriptor pfd = null;
		try {
			pfd = resolver.openFileDescriptor(uri, "r");
			BitmapFactory.decodeFileDescriptor(pfd.getFileDescriptor(), null, options);
		} catch (FileNotFoundException e) {
			Log.v(TAG, "File not found " + content);
			closePfd(pfd);
			return null;
		}


		options.inSampleSize = calculateInSampleSize(options.outWidth, options.outHeight, reqWidth, reqHeight);

		// If we're running on Honeycomb or newer, try to use inBitmap
		if (Utils.hasHoneycomb()) {
			addInBitmapOptions(options, cache);
		}

		// Decode bitmap with inSampleSize set
		options.inJustDecodeBounds = false;

		final Bitmap bitmap = BitmapFactory.decodeFileDescriptor(pfd.getFileDescriptor(), null, options);

		ExifInterface ei = getExifInterface(pfd.getFileDescriptor());
		closePfd(pfd);

		return scaleAndRotateBitmap(bitmap, ei, reqWidth, reqHeight, keepAspectRatio);
	}

	private static Bitmap scaleAndRotateBitmap(Bitmap bitmap, ExifInterface ei, int reqWidth, int reqHeight,
																						 boolean keepAspectRatio) {
		if (bitmap == null) {
			return null;
		}

		int sourceWidth = bitmap.getWidth();
		int sourceHeight = bitmap.getHeight();

		reqWidth = reqWidth > 0 ? reqWidth : Math.min(sourceWidth, mDeviceWidthPixels);
		reqHeight = reqHeight > 0 ? reqHeight : Math.min(sourceHeight, mDeviceHeightPixels);

		// scale
		if (reqWidth != sourceWidth || reqHeight != sourceHeight) {
			boolean needsResize;

			if (keepAspectRatio) {
				double widthCoef = (double) sourceWidth / (double) reqWidth;
				double heightCoef = (double) sourceHeight / (double) reqHeight;
				double aspectCoef = Math.min(widthCoef, heightCoef);

				reqWidth = (int) Math.floor(sourceWidth / aspectCoef);
				reqHeight = (int) Math.floor(sourceHeight / aspectCoef);

				// Update resize flag as values might revert back to original
				needsResize = reqWidth != sourceWidth || reqHeight != sourceHeight;
			} else {
				needsResize = true;
			}

			// After preserving aspect ratio, check if bitmap still needs scaling
			if (needsResize) {
				bitmap = Bitmap.createScaledBitmap(bitmap, reqWidth, reqHeight, true);
			}
		}

		// rotate
		if (ei != null) {
			final Matrix matrix = new Matrix();
			final int rotationAngle = calculateRotationAngle(ei);
			if (rotationAngle != 0) {
				matrix.postRotate(rotationAngle);
				bitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
			}
		}

		return bitmap;
	}

	private static int calculateRotationAngle(ExifInterface ei) {
		int rotationAngle = 0;
		final int orientation = ei.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);

		switch (orientation) {
			case ExifInterface.ORIENTATION_ROTATE_90:
				rotationAngle = 90;
				break;
			case ExifInterface.ORIENTATION_ROTATE_180:
				rotationAngle = 180;
				break;
			case ExifInterface.ORIENTATION_ROTATE_270:
				rotationAngle = 270;
				break;
		}

		return rotationAngle;
	}

	/**
	 * Decode and sample down a bitmap from a file input stream to the requested width and height.
	 *
	 * @param fileDescriptor The file descriptor to read from
	 * @param reqWidth       The requested width of the resulting bitmap
	 * @param reqHeight      The requested height of the resulting bitmap
	 * @param cache          The Cache used to find candidate bitmaps for use with inBitmap
	 * @return A bitmap sampled down from the original with the same aspect ratio and dimensions
	 * that are equal to or greater than the requested width and height
	 */
	public static Bitmap decodeSampledBitmapFromDescriptor(FileDescriptor fileDescriptor, int reqWidth, int reqHeight,
																												 boolean keepAspectRatio, Cache cache) {

		// First decode with inJustDecodeBounds=true to check dimensions
		final BitmapFactory.Options options = new BitmapFactory.Options();
		options.inJustDecodeBounds = true;
		BitmapFactory.decodeFileDescriptor(fileDescriptor, null, options);

		options.inSampleSize = calculateInSampleSize(options.outWidth, options.outHeight, reqWidth, reqHeight);

		// Decode bitmap with inSampleSize set
		options.inJustDecodeBounds = false;

		// If we're running on Honeycomb or newer, try to use inBitmap
		if (Utils.hasHoneycomb()) {
			addInBitmapOptions(options, cache);
		}

		Bitmap results = null;
		try {
			// This can throw an error on a corrupted image when using an inBitmap
			results = BitmapFactory.decodeFileDescriptor(fileDescriptor, null, options);
		} catch (Exception e) {
			// clear the inBitmap and try again
			options.inBitmap = null;
			results = BitmapFactory.decodeFileDescriptor(fileDescriptor, null, options);
			// If image is broken, rather than an issue with the inBitmap, we will get a NULL out in this case...
		}

		ExifInterface ei = getExifInterface(fileDescriptor);

		return scaleAndRotateBitmap(results, ei, reqWidth, reqHeight, keepAspectRatio);
	}

	public static Bitmap decodeSampledBitmapFromByteArray(byte[] buffer, int reqWidth, int reqHeight,
																												boolean keepAspectRatio, Cache cache) {

		// First decode with inJustDecodeBounds=true to check dimensions
		final BitmapFactory.Options options = new BitmapFactory.Options();
		options.inJustDecodeBounds = true;
		BitmapFactory.decodeByteArray(buffer, 0, buffer.length, options);

		options.inSampleSize = calculateInSampleSize(options.outWidth, options.outHeight, reqWidth, reqHeight);

		// Decode bitmap with inSampleSize set
		options.inJustDecodeBounds = false;

		// If we're running on Honeycomb or newer, try to use inBitmap
		if (Utils.hasHoneycomb()) {
			addInBitmapOptions(options, cache);
		}

		final Bitmap bitmap = BitmapFactory.decodeByteArray(buffer, 0, buffer.length, options);

		InputStream is = new ByteArrayInputStream(buffer);
		ExifInterface ei = getExifInterface(is);

		return scaleAndRotateBitmap(bitmap, ei, reqWidth, reqHeight, keepAspectRatio);
	}

	/**
	 * Calculate an inSampleSize for use in a {@link BitmapFactory.Options} object when decoding
	 * bitmaps using the decode* methods from {@link BitmapFactory}. This implementation calculates
	 * the closest inSampleSize that is a power of 2 and will result in the final decoded bitmap
	 * having a width and height equal to or larger than the requested width and height.
	 *
	 * @param imageWidth  The original width of the resulting bitmap
	 * @param imageHeight The original height of the resulting bitmap
	 * @param reqWidth    The requested width of the resulting bitmap
	 * @param reqHeight   The requested height of the resulting bitmap
	 * @return The value to be used for inSampleSize
	 */
	public static int calculateInSampleSize(int imageWidth, int imageHeight, int reqWidth, int reqHeight) {
		// BEGIN_INCLUDE (calculate_sample_size)
		// Raw height and width of image
		final int height = imageHeight;
		final int width = imageWidth;
		reqWidth = reqWidth > 0 ? reqWidth : width;
		reqHeight = reqHeight > 0 ? reqHeight : height;
		int inSampleSize = 1;
		if (height > reqHeight || width > reqWidth) {

			final int halfHeight = height / 2;
			final int halfWidth = width / 2;

			// Calculate the largest inSampleSize value that is a power of 2 and keeps both
			// height and width larger than the requested height and width.
			while ((halfHeight / inSampleSize) > reqHeight && (halfWidth / inSampleSize) > reqWidth) {
				inSampleSize *= 2;
			}

			// This offers some additional logic in case the image has a strange
			// aspect ratio. For example, a panorama may have a much larger
			// width than height. In these cases the total pixels might still
			// end up being too large to fit comfortably in memory, so we should
			// be more aggressive with sample down the image (=larger inSampleSize).

			long totalPixels = (width / inSampleSize) * (height / inSampleSize);

			// Anything more than 2x the requested pixels we'll sample down further
			final long totalReqPixelsCap = reqWidth * reqHeight * 2;

			while (totalPixels > totalReqPixelsCap) {
				inSampleSize *= 2;
				totalPixels = (width / inSampleSize) * (height / inSampleSize);
			}
		}
		return inSampleSize;
		// END_INCLUDE (calculate_sample_size)
	}

	@TargetApi(Build.VERSION_CODES.HONEYCOMB)
	private static void addInBitmapOptions(BitmapFactory.Options options, Cache cache) {
		//BEGIN_INCLUDE(add_bitmap_options)
		// inBitmap only works with mutable bitmaps so force the decoder to
		// return mutable bitmaps.
		options.inMutable = true;

		if (cache != null) {
			// Try and find a bitmap to use for inBitmap
			Bitmap inBitmap = cache.getBitmapFromReusableSet(options);

			if (inBitmap != null) {
				options.inBitmap = inBitmap;
			}
		}
		//END_INCLUDE(add_bitmap_options)
	}
}