1 files changed, 173 insertions, 0 deletions
diff --git a/SendGrid/SendGridMail/Header.cs b/SendGrid/SendGridMail/Header.cs
new file mode 100755
index 0000000..f1328f5
--- /dev/null
+++ b/SendGrid/SendGridMail/Header.cs
@@ -0,0 +1,173 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net.Mail;
+
+namespace SendGridMail
+{
+    public class Header : IHeader
+    {
+        private const string SendgridHeader = "X-Smtpapi";
+        private readonly HeaderSettingsNode _settings;
+
+        public Header()
+        {
+            _settings = new HeaderSettingsNode();
+        }
+
+        public void AddSubVal(string tag, IEnumerable<string> substitutions)
+        {
+            var keys = new List<String> {"sub", tag};
+            _settings.AddArray(keys, substitutions);
+        }
+
+        public void AddUniqueIdentifier(IDictionary<string, string> identifiers)
+        {
+            foreach (var key in identifiers.Keys)
+            {
+                var keys = new List<String> {"unique_args", key};
+                var value = identifiers[key];
+                _settings.AddSetting(keys, value);
+            }
+        }
+
+        public void SetCategory(string category)
+        {
+            var keys = new List<String> {"category"};
+            _settings.AddSetting(keys, category);
+        }
+
+        public void Enable(string filter)
+        {
+            AddFilterSetting(filter, new List<string>(){ "enable" }, "1");
+        }
+
+        public void Disable(string filter)
+        {
+            AddFilterSetting(filter, new List<string>(){"enable"}, "0");
+        }
+
+        public void AddFilterSetting(string filter, IEnumerable<string> settings, string value)
+        {
+            var keys = new List<string>() {"filters", filter, "settings" }.Concat(settings).ToList();
+            _settings.AddSetting(keys, value);
+        }
+
+        public void AddHeader(MailMessage mime)
+        {
+            mime.Headers.Add(SendgridHeader, AsJson());
+        }
+
+        public String AsJson()
+        {
+            if(_settings.IsEmpty()) return "";
+            return _settings.ToJson();
+        }
+
+        internal class HeaderSettingsNode
+        {
+            private readonly Dictionary<String, HeaderSettingsNode> _branches;
+            private IEnumerable<String> _array; 
+            private String _leaf;
+
+            public HeaderSettingsNode()
+            {
+                _branches = new Dictionary<string, HeaderSettingsNode>();
+            }
+
+            public void AddArray(List<String> keys, IEnumerable<String> value)
+            {
+                if (keys.Count == 0)
+                {
+                    _array = value;
+                }
+                else
+                {
+                    if (_leaf != null || _array != null)
+                        throw new ArgumentException("Attempt to overwrite setting");
+
+                    var key = keys.First();
+                    if (!_branches.ContainsKey(key))
+                        _branches[key] = new HeaderSettingsNode();
+
+                    var remainingKeys = keys.Skip(1).ToList();
+                    _branches[key].AddArray(remainingKeys, value);
+                }
+            }
+
+            public void AddSetting(List<String> keys, String value)
+            {
+                if (keys.Count == 0)
+                {
+                    _leaf = value;
+                }
+                else
+                {
+                    if(_leaf != null || _array != null) 
+                        throw new ArgumentException("Attempt to overwrite setting");
+                    
+                    var key = keys.First();
+                    if (!_branches.ContainsKey(key))
+                        _branches[key] = new HeaderSettingsNode();
+                    
+                    var remainingKeys = keys.Skip(1).ToList();
+                    _branches[key].AddSetting(remainingKeys, value);
+                }
+            }
+
+            public String GetSetting(params String[] keys)
+            {
+                return GetSetting(keys.ToList());
+            }
+
+            public String GetSetting(List<String> keys)
+            {
+                if (keys.Count == 0)
+                    return _leaf;
+                var key = keys.First();
+                if(!_branches.ContainsKey(key))
+                    throw new ArgumentException("Bad key path!");
+                var remainingKeys = keys.Skip(1).ToList();
+                return _branches[key].GetSetting(remainingKeys);
+            }
+
+            public IEnumerable<String> GetArray(params String[] keys)
+            {
+                return GetArray(keys.ToList());
+            }
+
+            public IEnumerable<String> GetArray(List<String> keys)
+            {
+                if (keys.Count == 0)
+                    return _array;
+                var key = keys.First();
+                if (!_branches.ContainsKey(key))
+                    throw new ArgumentException("Bad key path!");
+                var remainingKeys = keys.Skip(1).ToList();
+                return _branches[key].GetArray(remainingKeys);
+            }
+
+            public String GetLeaf()
+            {
+                return _leaf;
+            }
+
+            public String ToJson()
+            {
+                if (_branches.Count > 0)
+                    return "{" + String.Join(",", _branches.Keys.Select(k => Utils.Serialize(k)  + " : " + _branches[k].ToJson())) + "}";
+                if (_leaf != null)
+                    return Utils.Serialize(_leaf);
+                if (_array != null)
+                    return "[" + String.Join(", ", _array.Select(i => Utils.Serialize(i))) + "]";
+                return "{}";
+            }
+
+            public bool IsEmpty()
+            {
+                if (_leaf != null) return false;
+                return _branches == null || _branches.Keys.Count == 0;
+            }
+        }
+    }
+}