package com.reactnative.ivpusic.imagepicker;

import android.annotation.TargetApi;
import android.content.ContentUris;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Environment;
import android.provider.DocumentsContract;
import android.provider.MediaStore;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

class RealPathUtil {
    @TargetApi(Build.VERSION_CODES.KITKAT)
    static String getRealPathFromURI(final Context context, final Uri uri) throws IOException {

        final boolean isKitKat = Build.VERSION.SDK_INT == Build.VERSION_CODES.KITKAT;

        // DocumentProvider
        if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
            // ExternalStorageProvider
            if (isExternalStorageDocument(uri)) {
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];

                if ("primary".equalsIgnoreCase(type)) {
                    return Environment.getExternalStorageDirectory() + "/" + split[1];
                } else {
                    final int splitIndex = docId.indexOf(':', 1);
                    final String tag = docId.substring(0, splitIndex);
                    final String path = docId.substring(splitIndex + 1);

                    String nonPrimaryVolume = getPathToNonPrimaryVolume(context, tag);
                    if (nonPrimaryVolume != null) {
                        String result = nonPrimaryVolume + "/" + path;
                        File file = new File(result);
                        if (file.exists() && file.canRead()) {
                            return result;
                        }
                        return null;
                    }
                }
            }
            // DownloadsProvider
            else if (isDownloadsDocument(uri)) {
                final String id = DocumentsContract.getDocumentId(uri);
                final Uri contentUri = ContentUris.withAppendedId(
                        Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));

                return getDataColumn(context, contentUri, null, null);
            }
            // MediaProvider
            else if (isMediaDocument(uri)) {
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];

                Uri contentUri = null;
                if ("image".equals(type)) {
                    contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                } else if ("video".equals(type)) {
                    contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                } else if ("audio".equals(type)) {
                    contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                }

                final String selection = "_id=?";
                final String[] selectionArgs = new String[] {
                        split[1]
                };

                return getDataColumn(context, contentUri, selection, selectionArgs);
            }
        }
        // MediaStore (and general)
        else if ("content".equalsIgnoreCase(uri.getScheme())) {
            // Return the remote address
            if (isGooglePhotosUri(uri))
                return uri.getLastPathSegment();
            return getDataColumn(context, uri, null, null);
        }
        // File
        else if ("file".equalsIgnoreCase(uri.getScheme())) {
            return uri.getPath();
        }

        return null;
    }

    /**
     * If an image/video has been selected from a cloud storage, this method
     * should be call to download the file in the cache folder.
     *
     * @param context The context
     * @param fileName donwloaded file's name
     * @param uri file's URI
     * @return file that has been written
     */
    private static File writeToFile(Context context, String fileName, Uri uri) {
        String tmpDir = context.getCacheDir() + "/react-native-image-crop-picker";
        Boolean created = new File(tmpDir).mkdir();
        fileName = fileName.substring(fileName.lastIndexOf('/') + 1);
        File path = new File(tmpDir);
        File file = new File(path, fileName);
        try {
            FileOutputStream oos = new FileOutputStream(file);
            byte[] buf = new byte[8192];
            InputStream is = context.getContentResolver().openInputStream(uri);
            int c = 0;
            while ((c = is.read(buf, 0, buf.length)) > 0) {
                oos.write(buf, 0, c);
                oos.flush();
            }
            oos.close();
            is.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return file;
    }

    /**
     * Get the value of the data column for this Uri. This is useful for
     * MediaStore Uris, and other file-based ContentProviders.
     *
     * @param context The context.
     * @param uri The Uri to query.
     * @param selection (Optional) Filter used in the query.
     * @param selectionArgs (Optional) Selection arguments used in the query.
     * @return The value of the _data column, which is typically a file path.
     */
    private static String getDataColumn(Context context, Uri uri, String selection,
                                        String[] selectionArgs) {

        Cursor cursor = null;
        final String[] projection = {
                MediaStore.MediaColumns.DATA,
                MediaStore.MediaColumns.DISPLAY_NAME,
        };

        try {
            cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
                    null);
            if (cursor != null && cursor.moveToFirst()) {
                // Fall back to writing to file if _data column does not exist
                final int index = cursor.getColumnIndex(MediaStore.MediaColumns.DATA);
                String path = index > -1 ? cursor.getString(index) : null;
                if (path != null) {
                    return cursor.getString(index);
                } else {
                    final int indexDisplayName = cursor.getColumnIndexOrThrow(MediaStore.MediaColumns.DISPLAY_NAME);
                    String fileName = cursor.getString(indexDisplayName);
                    File fileWritten = writeToFile(context, fileName, uri);
                    return fileWritten.getAbsolutePath();
                }
            }
        } finally {
            if (cursor != null)
                cursor.close();
        }
        return null;
    }


    /**
     * @param uri The Uri to check.
     * @return Whether the Uri authority is ExternalStorageProvider.
     */
    private static boolean isExternalStorageDocument(Uri uri) {
        return "com.android.externalstorage.documents".equals(uri.getAuthority());
    }

    /**
     * @param uri The Uri to check.
     * @return Whether the Uri authority is DownloadsProvider.
     */
    private static boolean isDownloadsDocument(Uri uri) {
        return "com.android.providers.downloads.documents".equals(uri.getAuthority());
    }

    /**
     * @param uri The Uri to check.
     * @return Whether the Uri authority is MediaProvider.
     */
    private static boolean isMediaDocument(Uri uri) {
        return "com.android.providers.media.documents".equals(uri.getAuthority());
    }

    /**
     * @param uri The Uri to check.
     * @return Whether the Uri authority is Google Photos.
     */
    private static boolean isGooglePhotosUri(Uri uri) {
        return "com.google.android.apps.photos.content".equals(uri.getAuthority());
    }

    @TargetApi(Build.VERSION_CODES.KITKAT)
    private static String getPathToNonPrimaryVolume(Context context, String tag) {
        File[] volumes = context.getExternalCacheDirs();
        if (volumes != null) {
            for (File volume : volumes) {
                if (volume != null) {
                    String path = volume.getAbsolutePath();
                    if (path != null) {
                        int index = path.indexOf(tag);
                        if (index != -1) {
                            return path.substring(0, index) + tag;
                        }
                    }
                }
            }
        }
        return null;
    }

}