FatSecretGetMethod.java

/*
 * Copyright (C) 2013 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 com.eugene.fithealthmaingit.FatSecretSearchAndGet;

import android.net.Uri;
import android.util.Base64;
import android.util.Log;

import com.eugene.fithealthmaingit.Utilities.Globals;

import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Random;

import javax.crypto.Mac;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

public class FatSecretGetMethod {

    public JSONObject getFood(Long ab) {
        List<String> params = new ArrayList<>(Arrays.asList(generateOauthParams()));
        String[] template = new String[1];
        params.add("method=food.get");
        params.add("food_id=" + ab);
        params.add("oauth_signature=" + sign(Globals.APP_METHOD, Globals.APP_URL, params.toArray(template)));
        JSONObject food = null;
        try {
            URL url = new URL(Globals.APP_URL + "?" + paramify(params.toArray(template)));
            URLConnection api = url.openConnection();
            String line;
            StringBuilder builder = new StringBuilder();
            BufferedReader reader = new BufferedReader(new InputStreamReader(api.getInputStream()));
            while ((line = reader.readLine()) != null)
                builder.append(line);
            JSONObject foodGet = new JSONObject(builder.toString());
            food = foodGet.getJSONObject("food");
        } catch (Exception e) {
            Log.w("Fit", e.toString());
            e.printStackTrace();
        }
        return food;
    }

    private static String[] generateOauthParams() {
        return new String[]{
            "oauth_consumer_key=" + Globals.APP_KEY,
            "oauth_signature_method=HMAC-SHA1",
            "oauth_timestamp=" +
                Long.valueOf(System.currentTimeMillis() * 1000).toString(),
            "oauth_nonce=" + nonce(),
            "oauth_version=1.0",
            "format=json"};
    }

    private static String sign(String method, String uri, String[] params) {
        String[] p = {method, Uri.encode(uri), Uri.encode(paramify(params))};
        String s = join(p, "&");
        SecretKey sk = new SecretKeySpec(Globals.APP_SECRET.getBytes(), Globals.HMAC_SHA1_ALGORITHM);
        try {
            Mac m = Mac.getInstance(Globals.HMAC_SHA1_ALGORITHM);
            m.init(sk);
            return Uri.encode(new String(Base64.encode(m.doFinal(s.getBytes()), Base64.DEFAULT)).trim());
        } catch (java.security.NoSuchAlgorithmException e) {
            Log.w("FatSecret_TEST FAIL", e.getMessage());
            return null;
        } catch (java.security.InvalidKeyException e) {
            Log.w("FatSecret_TEST FAIL", e.getMessage());
            return null;
        }
    }

    private static String paramify(String[] params) {
        String[] p = Arrays.copyOf(params, params.length);
        Arrays.sort(p);
        return join(p, "&");
    }

    private static String join(String[] array, String separator) {
        StringBuilder b = new StringBuilder();
        for (int i = 0; i < array.length; i++) {
            if (i > 0)
                b.append(separator);
            b.append(array[i]);
        }
        return b.toString();
    }

    private static String nonce() {
        Random r = new Random();
        StringBuilder n = new StringBuilder();
        for (int i = 0; i < r.nextInt(8) + 2; i++)
            n.append(r.nextInt(26) + 'a');
        return n.toString();
    }
}