scanpay.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Text;
using Newtonsoft.Json;

namespace Scanpay
{
    public class Client
    {
        private const string HOSTNAME = "api.scanpay.dk";
        private readonly string apikey;

        public Client(string _apikey)
        {
            apikey = _apikey;
        }

        private Tres request<Tdata, Tres>(string url, Tdata data, Options opts)
        {
            var hostname = (opts == null || opts.hostname == null) ? HOSTNAME : opts.hostname;
            var _apikey = (opts == null || opts.auth == null) ? apikey : opts.auth;
            var req = (HttpWebRequest)WebRequest.Create("https://" + hostname + url);
            var auth = "Basic " + Convert.ToBase64String(Encoding.UTF8.GetBytes(_apikey));
            req.Method = "GET";
            req.ContentType = "application/json";
            req.Headers["X-SDK"] = ".NET-0.1.0";
            req.Headers[HttpRequestHeader.Authorization] = auth;
            if (opts != null && opts.headers != null)
            {
                foreach(KeyValuePair<string, string> hdr in opts.headers)
                {
                    req.Headers[hdr.Key] = hdr.Value;
                }
            }

            req.AutomaticDecompression = DecompressionMethods.GZip;
            if (data != null)
            {
                req.Method = "POST";
                using (var sw = new StreamWriter(req.GetRequestStream()))
                using (JsonTextWriter jtw = new JsonTextWriter(sw))
                {
                    JsonSerializer.Create().Serialize(jtw, data);
                    jtw.Flush();
                }
            }

            using (var res = (HttpWebResponse)req.GetResponse())
            using (var stream = res.GetResponseStream())
            using (var sr = new StreamReader(stream))
            using (var jtr = new JsonTextReader(sr))
            {
                return JsonSerializer.Create().Deserialize<Tres>(jtr);
            }
        }

        public string newURL(NewURLReq data, Options opts=null)
        {
            var resobj = request<NewURLReq, NewURLRes>("/v1/new", data, opts);
            return resobj.url;
        }

        public SeqRes seq(ulong seqnum, Options opts=null)
        {
            return request<NullReq, SeqRes>("/v1/seq/" + seqnum, null, opts);
        }

        private bool constTimeEquals(string a, string b)
        {
            uint diff = (uint)a.Length ^ (uint)b.Length;
            for (int i = 0; i < a.Length && i < b.Length; i++) {
                diff |= (uint)(a[i] ^ b[i]);
            }
            return diff == 0;
        }

        public Ping handlePing(byte[] body, string signature, Options opts=null)
        {
            var _apikey = (opts == null || opts.auth == null) ? apikey : opts.auth;
            var binApikey = Encoding.UTF8.GetBytes(_apikey);
            var hasher = new System.Security.Cryptography.HMACSHA256(binApikey);
            var binDigest = hasher.ComputeHash(body);
            var digest = Convert.ToBase64String(binDigest);
            if (!constTimeEquals(digest, signature)) {
                throw new Exception("invalid ping signature");
            }
            using (var ms = new MemoryStream(body))
            using (var sr = new StreamReader(ms))
            using (var jtr = new JsonTextReader(sr)) {
                return JsonSerializer.Create().Deserialize<Ping>(jtr);
            }
        }

        public Ping handlePing(string body, string signature, Options opts=null)
        {
            return handlePing(Encoding.UTF8.GetBytes(body), signature);
        }
        internal class NullReq{}
    }
        public class NewURLReq
        {
            public string   orderid;
            public string   successurl;
            public Item[]   items;
            public Billing  billing;
            public Shipping shipping;
            public string   language;
            public bool     autocapture;
            public string   lifetime;
        }

        public class Item
        {
            public string name;
            public uint   quantity;
            public string price;
            public string sku;
        }

        public class Billing
        {
            public string   name;
            public string   company;
            public string   vatin;
            public string   gln;
            public string   email;
            public string   phone;
            public string[] address;
            public string   city;
            public string   zip;
            public string   state;
            public string   country;
        }

        public class Shipping
        {
            public string   name;
            public string   company;
            public string   email;
            public string   phone;
            public string[] address;
            public string   city;
            public string   zip;
            public string   state;
            public string   country;
        }

        public class NewURLRes
        {
            public string url;
        }

        public class SeqRes
        {
            public ulong    seq;
            public Change[] changes;
        }

        public class Change
        {
            public ulong  id;
            public uint   rev;
            public string orderid;
            public string error;
            public Time time;
            public Act[] acts;
            public Totals totals;
        }

        public class Time
        {
            public long created;
            public long authorized;
        }

        public class Act
        {
            public string act;
            public long   time;
            public string total;
        }

        public class Totals
        {
            public string authorized;
            public string captured;
            public string refunded;
            public string left;
        }

        public class Ping
        {
            public ulong shopid;
            public ulong seq;
        }

        public class Options
        {
            public string                     hostname;
            public string                     auth;
            public Dictionary<string, string> headers;
        }

}