Pick the Right Meal Using C#, ASP.NET and Nutritionix

Install-Package Twilio.Mvc

Install-Package ZXing.Net

Install-Package Nutritionix

using System.Drawing;
using System.Net.Http;
using System.Text;

using Twilio;
using Twilio.TwiML;
using Twilio.TwiML.Mvc;
using Nutritionix;
using ZXing;

public async Task<ActionResult> Inbound(int numMedia, string body)
{
    var response = new TwilioResponse();

    // Trim incoming text to remove whitespace
    body = body.Trim();

    // Code to generate nutrition info result...
    return new TwiMLResult(response);	
}

// No images sent in
if (numMedia == 0)
{
   response.Message("You didn't send any barcodes! Please send in well-focused and zoomed in barcodes with the word 'total' to get total nutrition values or 'compare' to get a comparison of the items.");
   return new TwiMLResult(response);
}

<Response>
   <Message>You didn't send any barcodes! Please send in well-focused and zoomed in barcodes with the word 'total' to get total nutrition values or 'compare' to get a comparison of the items.</Message>
</Response>

// Decode the barcodes
string[] eanCodes = await DecodeBarcodes(numMedia);

if (eanCodes == null)
{
   // There was an error with one of the barcodes. Bail so user can try again.
   response.Message("One of your barcodes was not recognized. Please try cropping your image or taking the picture again closer to the barcode.");
   return new TwiMLResult(response);
}

private async Task<string[]> DecodeBarcodes(int numberOfImages)
{
   // Build a List<Bitmap> from incoming images
   var images = new List<Bitmap>(numberOfImages);

   // Build an array of EAN codes from reading the barcodes
   var eanCodes = new string[numberOfImages];

   var httpClient = new HttpClient();
   var reader = new BarcodeReader();

   for (int i = 0; i < numberOfImages; i++)
   {
       Bitmap bitmap;

       using (var stream = await httpClient.GetStreamAsync(Request["MediaUrl" + i]))
       {
           using (bitmap = (Bitmap)Bitmap.FromStream(stream))
           {
               var result = reader.Decode(bitmap);

               if (result == null)
               {
                   // Couldn't read this barcode, we'll return null to indicate we should bail...
                   return null;
               }

               eanCodes[i] = result.Text;
           }
       }
   }

   return eanCodes;
}

private string _nutritionixId = "[Your Nutritionix Application ID]";
private string _nutritionixKey = "[Your Nutritionix Application Key]";

List<Item> foodItems = new List<Item>();
List<string> skippedBarcodes = new List<string>();

private void LookupNutritionInfo(string[] eanCodes, ref List<Item> foodItems, ref List<string> skippedBarcodes)
{
   // Initialize the NutritionixClient
   var nutritionix = new NutritionixClient();
   nutritionix.Initialize(_nutritionixId, _nutritionixKey);

   // Create lists for food items and any barcodes that aren't in the database
   foodItems = new List<Item>(eanCodes.Length);
   skippedBarcodes = new List<string>();

   // Loop through each barcode
   foreach (var barcode in eanCodes)
   {
       Item food = null;

       try
       {
           // Fetch nutrition info by EAN code
           food = nutritionix.RetrieveItemByUPC(barcode);
       }
       catch
       {
           // Invalid barcode format results in a 404. We'll add it to the skipped barcodes list.
           skippedBarcodes.Add(barcode);
           return;
       }

       if (food != null)
       {
           foodItems.Add(food);
       }
       else
       {
           // One of the food items is not available in Nutritionix.
           skippedBarcodes.Add(barcode);
       }
   }
}

LookupNutritionInfo(eanCodes, ref foodItems, ref skippedBarcodes);

if (skippedBarcodes.Count > 0)
{
   // Let's tell the users that we couldn't find their item(s)...
   var builder = new StringBuilder();

   builder.Append("Sorry but we couldn't find one or more of your items. Please try again without the following EANs which were not found in the Nutritionix database: ");

   foreach (var barcode in skippedBarcodes)
   {
       builder.Append(barcode + " ");
   }

   response.Message(builder.ToString());
   return new TwiMLResult(response);
}

private string GetSingleItemNutrition(Item foodItem)
{
   return String.Format(
           "Here are the details for {0} {1}: {2} calories, {3}g protein, {4}g total carbohydrates, {5}g total fat.",
           foodItem.BrandName,
           foodItem.Name,
           foodItem.NutritionFact_Calories,
           foodItem.NutritionFact_Protein,
           foodItem.NutritionFact_TotalCarbohydrate,
           foodItem.NutritionFact_TotalFat
   );
}

private static string GetTotalNutrition(List<Item> foodItems, string[] eanCodes)
{
   // Default to returning total nutrition info
   var totalCalories = foodItems.Sum((item) => item.NutritionFact_Calories).Value;
   var totalProtein = foodItems.Sum((item) => item.NutritionFact_Protein).Value;
   var totalCarbs = foodItems.Sum((item) => item.NutritionFact_TotalCarbohydrate).Value;
   var totalFat = foodItems.Sum((item) => item.NutritionFact_TotalFat).Value;

   return string.Format("Here are the totals for the items you requested: {0} calories, {1}g protein, {2}g carbohydrates and {3}g total fat.", totalCalories, totalProtein, totalCarbs, totalFat);
}

private string CompareNutrition(List<Item> foodItems, string[] eanCodes)
{
   var lowestCalories = foodItems.Aggregate(
                               (item1, item2) => item1.NutritionFact_Calories < item2.NutritionFact_Calories ? item1 : item2
                           );

   var highestProtein = foodItems.Aggregate(
                               (item1, item2) => item1.NutritionFact_Protein > item2.NutritionFact_Protein ? item1 : item2
                           );

   var lowestCarbs = foodItems.Aggregate(
                               (item1, item2) => item1.NutritionFact_TotalCarbohydrate < item2.NutritionFact_TotalCarbohydrate ? item1 : item2
                           );

   var lowestFat = foodItems.Aggregate(
                               (item1, item2) => item1.NutritionFact_TotalFat < item2.NutritionFact_TotalFat ? item1 : item2
                           );

   return string.Format(
       "Lowest calories: {0} {1} (barcode: {2}) with {3} calories. Highest protein: {4} {5} (barcode: {6}) with {7}g of protein. Lowest total carbs: {8} {9} (barcode: {10}) with {11}g carbs. Lowest total fat: {12} {13} (barcode: {14}) with {15}g fat.",
       lowestCalories.BrandName,
       lowestCalories.Name,
       eanCodes[foodItems.IndexOf(lowestCalories)],
       lowestCalories.NutritionFact_Calories,
       highestProtein.BrandName,
       highestProtein.Name,
       eanCodes[foodItems.IndexOf(highestProtein)],
       highestProtein.NutritionFact_Protein,
       lowestCarbs.BrandName,
       lowestCarbs.Name,
       eanCodes[foodItems.IndexOf(lowestCarbs)],
       lowestCarbs.NutritionFact_TotalCarbohydrate,
       lowestFat.BrandName,
       lowestFat.Name,
       eanCodes[foodItems.IndexOf(lowestFat)],
       lowestFat.NutritionFact_TotalFat
   );
}

private string GetNutritionInfoResponse(int numMedia, string keyword, List<Item> foodItems, string[] eanCodes)
{
   string responseString = "";

   // Depending on number of items and the keyword in the Body, run some nutrition calculations
   if (numMedia == 1)
   {
       // Single item, just return details for that item.
       responseString = GetSingleItemNutrition(foodItems[0]);
   }
   else if (keyword == String.Empty)
   {
       // Default to totals
       responseString = GetTotalNutrition(foodItems, eanCodes);
   }
   else if (String.Equals(keyword, "total", StringComparison.OrdinalIgnoreCase))
   {
       // User explicitly requested total nutrition info
       responseString = GetTotalNutrition(foodItems, eanCodes);
   }
   else if (String.Equals(keyword, "compare", StringComparison.OrdinalIgnoreCase))
   {
       // User requested item comparison
       responseString = CompareNutrition(foodItems, eanCodes);
   }
   else
   {
       // Invalid keyword
       responseString = String.Format("You sent in '{0}' which is not a valid keyword. Please send in well-focused and zoomed in barcodes with the word 'total' to get total nutrition values or 'compare' to get a comparison of the items.", keyword);
   }

   return responseString;
}