using System;
using System.Linq;
using System.Threading.Tasks;
using MervisDb_GetData_Example.MervisDbService;

namespace MervisDb_GetData_Example {
 class Program {
  static void Main(string[] args) {
   //
   // Demo of asynchronous methods.
   //
   var task = Task.Run(async() => {
    //
    // Create access to the real server.
    // Without SSL connections, you have to remove binding parameters "<security mode="Transport"/>" in the App.config.
    // The client is automatically generated from the WSDL file available here: https://kb.mervis.info/doku.php/en:mervis-db:10-api
    //
    using(HistoryDbAccessClient client = new HistoryDbAccessClient("HistoryAccess", "https://localhost:9876/RcWareDbAccess")) {
     // Authentication credetials in the database.
     Credentials credentials = new Credentials {
      Name = "XXXX", Password = "YYYY"
     };

     // Specification of the variables through Key-Value.
     // Here we use 2 variables.
     KeyValuePair[][] keys = new KeyValuePair[][] {
      new KeyValuePair[] {
        new KeyValuePair {
         Key = "DPGuid", Value = "338E2882-D72B-4D17-A241-73E8BC30F458"
        }, new KeyValuePair {
         Key = "StationName", Value = "AAABBB"
        }
       },
       new KeyValuePair[] {
        new KeyValuePair {
         Key = "DPGuid", Value = "CC80211D-3D29-4CC2-91A2-F69483D566B5"
        }, new KeyValuePair {
         Key = "StationName", Value = "AAABBB"
        }
       }
     };

     // From-To dates. The dates must be specified in the UTC time zone.
     DateTime utcTo = DateTime.UtcNow;
     DateTime utcFrom = DateTime.UtcNow.AddDays(-1);

     // Retrieving the data goes through cycling of values and variables. The server returns recommended values needed for the the next cycle.
     int variableOffset = 0; // the offset of the variable
     int variableCount = 10; // maximal number of variables returned in one request
     int valueOffset; // the offset of the value
     int valueCount = 1000; // maximal values in on request

     Console.WriteLine("Reading values...");

     do {
      valueOffset = 0;
      do {
       // Execute the request.
       var result = await client.GetDataAsyncAsync(credentials, keys, utcFrom, utcTo, variableOffset, variableCount, valueOffset, valueCount);

       // Check the return code. "0;OK" is what we want.
       if (!result.ReturnCode.StartsWith("0;")) {
        Console.WriteLine("Error on reading: {0}", result.ReturnCode);
       }

       // Cycle through the data and print it out.
       foreach(var valRecord in result.Data) {
        Console.WriteLine("Variable: {0}", String.Concat(valRecord.Keys.Select((i) => {
         return String.Format("{0}={1}; ", i.Key, i.Value);
        })));

        foreach(var value in valRecord.Vals) {
         Console.WriteLine("{0}->{1} [{2}] {3}", value.Ts, value.Gt, value.Hvt, value.Dv /* Use value type according to the Hvt (History Value Type) */ );
        }
       }

       valueOffset = result.NextValueOffset;
       variableOffset = result.NextVariableOffset;
      }
      while (valueOffset != -1);
     }
     while (variableOffset != -1);
    }
   });

   Console.WriteLine("DB communication is running in background");

   try {
    task.Wait();
   } catch (Exception exc) {
    Console.WriteLine("Exception: {0}", exc.ToString());
   }

   Console.WriteLine("DB communication finished");

   Console.ReadLine();
  }
 }
}