DowloadRequestRepository.java

package com.tapura.podmorecasts.download;


import android.content.Context;
import android.content.SharedPreferences;
import android.support.annotation.Nullable;

import com.google.gson.Gson;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

public class DownloadRequestRepository {

    private static final String SHARED_PREF_KEY = "download_request_repo";
    private final Context mContext;
    private List<DownloadRequest> mRequests;

    public DownloadRequestRepository(Context c) {
        mContext = c;
        mRequests = getRequestsFromSharedPreferences();
    }

    private List<DownloadRequest> getRequestsFromSharedPreferences() {
        List<DownloadRequest> list = new ArrayList<>();
        SharedPreferences sharedPref = mContext.getSharedPreferences(SHARED_PREF_KEY, Context.MODE_PRIVATE);
        Gson gson = new Gson();
        Map<String, ?> all = sharedPref.getAll();
        for (String index : all.keySet()) {
            String object = (String) all.get(index);
            list.add(gson.fromJson(object, DownloadRequest.class));
        }
        return list;
    }

    @Nullable
    public DownloadRequest get(long refId) {
        for (DownloadRequest r : mRequests) {
            if (r.getRefId() == refId) {
                return r;
            }
        }
        return null;
    }

    public void append(DownloadRequest downloadRequest) {
        mRequests.add(downloadRequest);
        flush();
    }

    public long getId(String feed, int epiIndex) {
        for (DownloadRequest r : mRequests) {
            if (feed.equals(r.getFeed()) && epiIndex == r.getEpisodePos()) {
                return r.getRefId();
            }
        }
        return -1;
    }

    public void remove(long id) {
        for (DownloadRequest r : mRequests) {
            if (r.getRefId() == id) {
                mRequests.remove(r);
                flush();
                return;
            }
        }
    }

    private void flush() {
        SharedPreferences sharedPrefForClear = mContext.getSharedPreferences(SHARED_PREF_KEY, Context.MODE_PRIVATE);
        SharedPreferences.Editor editorForClear = sharedPrefForClear.edit();

        editorForClear.clear();

        if (editorForClear.commit()) {
            SharedPreferences sharedPref = mContext.getSharedPreferences(SHARED_PREF_KEY, Context.MODE_PRIVATE);
            SharedPreferences.Editor editor = sharedPref.edit();
            Gson gson = new Gson();
            for (DownloadRequest request : mRequests) {
                String stringRequest = gson.toJson(request);
                editor.putString(String.valueOf(request.getRefId()), stringRequest);
            }

            editor.apply();
        }

    }

    public long[] getAllId(String feed) {
        return mRequests.stream().filter(req -> req.getFeed().equals(feed)).mapToLong(DownloadRequest::getRefId).toArray();
    }

    public void remove(long[] ids) {
        for (long id : ids) {
            remove(id);
        }
    }
}