using Microsoft.WindowsAzure.Storage.Table;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;


public static class CloudTableExtensions
{
    /// <summary>
    /// Demonstrate the most efficient storage query - the point query - where both partition key and row key are specified.
    /// </summary>
    /// <param name="table">Sample table name</param>
    /// <param name="partitionKey">Partition key - i.e., last name</param>
    /// <param name="rowKey">Row key - i.e., first name</param>
    /// <returns>A Task object</returns>
    public static T GetEntity<T>(this CloudTable table, string partitionKey, string rowKey) where T : class, ITableEntity
    {
        TableOperation retrieveOperation = TableOperation.Retrieve<T>(partitionKey, rowKey);
        TableResult result = table.Execute(retrieveOperation);
        T customer = result.Result as T;
        return customer;
    }

    /// <summary>
    /// The Table Service supports two main types of insert operations.
    ///  1. Insert - insert a new entity. If an entity already exists with the same PK + RK an exception will be thrown.
    ///  2. Replace - replace an existing entity. Replace an existing entity with a new entity.
    ///  3. Insert or Replace - insert the entity if the entity does not exist, or if the entity exists, replace the existing one.
    ///  4. Insert or Merge - insert the entity if the entity does not exist or, if the entity exists, merges the provided entity properties with the already existing ones.
    /// </summary>
    /// <param name="table">The sample table name</param>
    /// <param name="entity">The entity to insert or merge</param>
    /// <returns>A Task object</returns>
    public static T InsertOrUpdateEntity<T>(this CloudTable table, T entity) where T : class, ITableEntity
    {
        if (entity == null)
        {
            throw new ArgumentNullException("Specified entity is null.");
        }

        // Create the InsertOrReplace table operation
        TableOperation insertOrMergeOperation = TableOperation.InsertOrReplace(entity);

        // Execute the operation.
        TableResult result = table.Execute(insertOrMergeOperation);
        T insertedCustomer = result.Result as T;

        return insertedCustomer;
    }

    /// <summary>
    /// Delete an entity
    /// </summary>
    /// <param name="table">Sample table name</param>
    /// <param name="deleteEntity">Entity to delete</param>
    /// <returns>A Task object</returns>
    public static void DeleteEntity<T>(this CloudTable table, T deleteEntity) where T : class, ITableEntity
    {
        if (deleteEntity == null)
        {
            throw new ArgumentNullException("Specified entity was null.");
        }

        TableOperation deleteOperation = TableOperation.Delete(deleteEntity);
        table.Execute(deleteOperation);
    }
}