public class SearchProduct {
private int itemCount;
private double totalPrice;
private String zapposKey;
private double maxPrice;
private ArrayList<Product> allProductList;
private ArrayList<Combination> desiredProductList;
private final double TOL = Math.pow(10, -7);
public SearchProduct(int num, double total, String key) {
itemCount = num;
totalPrice = total;
zapposKey = key;
maxPrice = Integer.MAX_VALUE; // will set later
allProductList = new ArrayList<Product>();
desiredProductList = new ArrayList<Combination>();
}
/** Get the double value of JSON object */
private Double getDouble(Object item) {
return Double.parseDouble(((String) ((JSONObject) item).get("price")).substring(1));
}
/** Do a Zappos Search and return the result and returns the result */
public String GetResult(int page) throws IOException {
String urlStr =
"http://api.zappos.com/Search?key="
+ zapposKey
+ "&term=&limit=100&sort={\"price\":\"asc\"}";
if (page != 0) {
urlStr += "&page=" + page;
}
URL url = new URL(urlStr);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
if (conn.getResponseCode() != 200) {
throw new IOException(conn.getResponseMessage());
}
// Buffer the result into a string
BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
StringBuilder sb = new StringBuilder();
String line;
while ((line = rd.readLine()) != null) {
sb.append(line);
}
rd.close();
conn.disconnect();
return sb.toString();
}
/** Parse the Search result and return JSON Array */
public static JSONArray resultParse(String reply) throws ParseException {
JSONParser parser = new JSONParser();
JSONObject obj = (JSONObject) parser.parse(reply);
JSONArray resultArray = (JSONArray) obj.get("results");
return resultArray;
}
/** Give the users search criteria (item count and price range), find products in that range. */
@SuppressWarnings("unchecked")
private void findProducts() throws IOException, ParseException {
int page = 0;
int priceRange = 2;
// Get first 100 lowest priced products listed in Zappos.
String reply = GetResult(page);
JSONArray resultArray = resultParse(reply);
// Lowest priced product, offcourse the first one.
double lowestPrice = getDouble(resultArray.get(0));
// If you can't match users criteria with the lowest priced item, return NULL.
if ((lowestPrice * itemCount) < (totalPrice + priceRange)) {
// We can proceed, find the max price given the min price.
maxPrice = totalPrice - (itemCount - 1) * (lowestPrice);
// We have first page, fetch the next page.
page++;
// Last product price.
Double lastPrice = getDouble(resultArray.get(resultArray.size() - 1));
// Keep fetching till we get products within our search range.
while (lastPrice < maxPrice) {
String nextPage = GetResult(page);
JSONArray nextArray = resultParse(nextPage);
// append new page of results to original array
resultArray.addAll(nextArray);
// get new last product and price
lastPrice = getDouble(nextArray.get(nextArray.size() - 1));
page++;
}
allProductList.add(new Product((JSONObject) resultArray.get(0)));
// count how many times a price has already shown up
int already = 1;
int numPrices = 1;
// go through the whole
for (int i = 1; i < resultArray.size() && getDouble(resultArray.get(i)) < maxPrice; i++) {
System.out.println("I : " + i);
double currentPrice = getDouble(resultArray.get(i));
if (currentPrice > allProductList.get(numPrices - 1).getPrice()) {
allProductList.add(new Product((JSONObject) resultArray.get(i)));
numPrices++;
already = 1;
} else if (Math.abs(currentPrice - allProductList.get(numPrices - 1).getPrice()) < TOL
&& already < itemCount) {
allProductList.add(new Product((JSONObject) resultArray.get(i)));
numPrices++;
already++;
} else {
// Finding products with the same price as the last one added to the productObjects list
while (i < resultArray.size()
&& Math.abs(currentPrice - allProductList.get(numPrices - 1).getPrice()) < TOL) {
i++;
currentPrice = getDouble(resultArray.get(i));
}
i++;
already = 0;
}
}
}
}
/** Finds the product combinations of numItems items with $1 of the totalPrice */
private void findProductCombination(
ArrayList<Product> productList, double target, ArrayList<Product> partial) {
// Keeping +-2 dollar as the price search window.
int priceBuffer = 2;
// if partial size > numItems, you already have too many items, so stop
if (partial.size() > itemCount) {
return;
}
double sum = 0;
for (Product x : partial) sum += x.getPrice();
if (Math.abs(sum - target) < priceBuffer
&& partial.size() == itemCount
&& desiredProductList.size() < 25) {
// if no price combos yet, just add it on
if (desiredProductList.size() == 0) {
desiredProductList.add(new Combination(partial, totalPrice));
}
// otherwise, check it against the most recent product combo to make sure you're not repeating
// TODO: check all product combos
else {
Combination testerCombo = desiredProductList.get(desiredProductList.size() - 1);
Combination partialCombo = new Combination(partial, totalPrice);
if (!partialCombo.equals(testerCombo)) {
desiredProductList.add(partialCombo);
}
}
}
// if sum is at or within $1 of target, then stop - done!
if (sum >= target + priceBuffer) {
return;
}
// otherwise, recursively continue adding another product to combo and test it
for (int i = 0; i < productList.size() && !(partial.size() == itemCount && sum < target); i++) {
ArrayList<Product> remaining = new ArrayList<Product>();
Product n = productList.get(i);
for (int j = i + 1; j < productList.size(); j++) {
remaining.add(productList.get(j));
}
ArrayList<Product> partial_rec = new ArrayList<Product>(partial);
partial_rec.add(n);
findProductCombination(remaining, target, partial_rec);
}
}
/** Returns the gift combinations that are closest to the total dollar amount */
@SuppressWarnings("unchecked")
public String getGiftCombos() throws IOException, ParseException {
// get products from API
System.out.println("Searching Zappos...");
this.findProducts();
// find combinations that work
this.findProductCombination(allProductList, totalPrice, new ArrayList<Product>());
Collections.sort(desiredProductList);
// see if you have any combos
if (desiredProductList.size() != 0) {
String toPrint = "\nDone!\n";
for (Combination x : desiredProductList) {
toPrint += x.toString() + "\n";
}
return toPrint;
} else {
return "No items matching your criteria. Try fewer items or higher price range.";
}
}
public static void main(String[] args) {
Scanner reader = new Scanner(System.in);
System.out.println("Enter desired # of products : ");
int itemcount = reader.nextInt();
System.out.println("Enter desired $ amount : ");
double price = reader.nextInt();
System.out.println("Enter your Key to Zappos API: ");
String zapposKey = reader.next();
try {
SearchProduct searcher = new SearchProduct(itemcount, price, zapposKey);
System.out.println(searcher.getGiftCombos());
} catch (ParseException e) {
// occurs if parsed incorrectly
System.err.println("Sorry, we couldn't parse the server's response.");
e.printStackTrace();
} catch (IOException e) {
// occurs if response code wasn't 200
System.err.println("Sorry, something went wrong with our search.");
e.printStackTrace();
}
}
}
