using System.Configuration;
using System.IO;
using HeuristicLab.Services.Optimization.Billing.Interfaces;
using Microsoft.WindowsAzure;
using Microsoft.WindowsAzure.StorageClient;

namespace HeuristicLab.Services.Optimization.Billing.BillingEngine {
  public class AzureInvoiceDao : IInvoiceDao {
    private CloudStorageAccount storageAccount;
    private CloudStorageAccount StorageAccount {
      get {
        if (storageAccount == null) {
          storageAccount = CloudStorageAccount.Parse(ConfigurationManager.AppSettings[AzureConstants.CLOUD_STORAGE_SETTINGS_STRING]);
        }
        return storageAccount;
      }
    }

    private CloudBlobClient blobClient;
    private CloudBlobClient BlobClient {
      get {
        if (blobClient == null) {
          blobClient = StorageAccount.CreateCloudBlobClient();
        }
        return blobClient;
      }
    }

    public AzureInvoiceDao() {

    }

    public bool SaveDocument(string documentName, string contents) {
      CloudBlobContainer container = BlobClient.GetContainerReference(AzureConstants.INVOICE_BLOB_CONTAINER);
      container.CreateIfNotExist();
      var blob = container.GetBlobReference(documentName);
      blob.UploadText(contents);
      return true;
    }

    public string LoadDocument(string documentName) {
      CloudBlobContainer container = BlobClient.GetContainerReference(AzureConstants.INVOICE_BLOB_CONTAINER);
      container.CreateIfNotExist();
      var blob = container.GetBlobReference(documentName);
      return blob.DownloadText();
    }

    public void LoadDocument(string documentName, Stream target) {
      CloudBlobContainer container = BlobClient.GetContainerReference(AzureConstants.INVOICE_BLOB_CONTAINER);
      container.CreateIfNotExist();
      var blob = container.GetBlobReference(documentName);
      blob.DownloadToStream(target);
    }


    private static class AzureConstants {
      public static readonly string INVOICE_BLOB_CONTAINER = "invoices";
      public static readonly string CLOUD_STORAGE_SETTINGS_STRING = "StorageConnectionString";
    }
  }
}