cardmarketbot/ConsoleApp3/SevdeskService.cs

using System.Runtime.Serialization;
using System.Text;
using ConsoleApp3.DataContracts;
using Newtonsoft.Json;


namespace CardmarketBot
{
    class SevdeskService
    {
        private readonly HttpClient _client;
        private readonly Random _random = new();

        public SevdeskService(string key)
        {
            _client = new HttpClient
            {
                DefaultRequestHeaders =
                {
                    { "Authorization", "7251554968610b78ca865b2b774b4134" },
                    { "Accept", "application/json" }
                }
            };
        }

       
        public async void Create(ModelRechnung rechnung)
        {

            rechnung.Invoice.InvoiceNumber = string.Format("RE-{0}", await GetNextInvoiceNumber());
            await WriteInv(rechnung);
        }

       
        private async Task<bool> WriteInv(ModelRechnung invoice)
        {
            var uri = "https://my.sevdesk.de/api/v1/Invoice/Factory/saveInvoice";

            var t = JsonConvert.SerializeObject(invoice);
            var content = new StringContent(JsonConvert.SerializeObject(invoice),Encoding.UTF8, "application/json");

            var resp = await _client.PostAsync(uri, content);
            //Console.WriteLine(resp.EnsureSuccessStatusCode());
            var contents = await resp.Content.ReadAsStringAsync();
            
            return true;
        }

        private async Task<Invoices> GetInvoiceAsync(string id)
        {
            //var uri = LexofficeApiAddressesBuilder.InvoiceUri(id);
            var uri = "https://my.sevdesk.de/api/v1/Invoice/56501411/getPositions";
            var response = await _client.GetAsync(uri).ConfigureAwait(false);

            response.EnsureSuccessStatusCode();

            var contents = await response.Content.ReadAsStringAsync().ConfigureAwait(false);

            var jsonSerializerSettings = new JsonSerializerSettings
            {
                MissingMemberHandling = MissingMemberHandling.Ignore
            };
            return JsonConvert.DeserializeObject<Invoices>(contents, jsonSerializerSettings);
        }

        private async Task<string> GetNextInvoiceNumber()
        {
            var uri = "https://my.sevdesk.de/api/v1/SevSequence/Factory/getByType?objectType=Invoice&type=RE";
            var response = await _client.GetAsync(uri).ConfigureAwait(false);
            response.EnsureSuccessStatusCode();
            var contents = await response.Content.ReadAsStringAsync().ConfigureAwait(false);

            var jsonSerializerSettings = new JsonSerializerSettings
            {
                MissingMemberHandling = MissingMemberHandling.Ignore
            };
            var ob = JsonConvert.DeserializeObject<RNumbers>(contents, jsonSerializerSettings);

            return ob.ConfigRechnungsnummer.NextNumber;
            
        }
    }

    [DataContract]
    class RNumbers
    {
        [JsonProperty("objects")] public ConfigRechnungnummer ConfigRechnungsnummer { get; set; }
    }

    [DataContract]
    class ConfigRechnungnummer
    {
        [DataMember(Name = "format", EmitDefaultValue = false)]
        [JsonProperty(PropertyName = "format")]
        public string Format { get; set; } = "";

        [DataMember(Name = "nextSequence", EmitDefaultValue = false)]
        [JsonProperty(PropertyName = "nextSequence")]
        public string NextNumber { get; set; } = "";
    }
}