Add project files.

Beam.Dynamic/Binding.cs

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+
+using aeqw89.DataKeys;
+using HtmlAgilityPack;
+using System.Text.Json.Serialization;
+
+namespace Beam.Dynamic {
+    public class Binding(DataKey<Binding> key) : IKeyed<Binding> {
+        public Binding(string key) : this(new DataKey<Binding>(key)) { }
+        public Binding() : this("") { }
+
+        [JsonRequired]
+        public DataKey<Binding> Key { get; set; } = key;
+        [JsonRequired]
+        public BindingType Type { get; set; }
+
+        public string? ArrayDelimiters { get; set; }
+        public string? XPath { get; set; }
+        public string? CssPath { get; set; }
+        private IDataProvider? Provider_;
+        public IDataProvider? Provider {
+            get => Provider_;
+            set {
+                if (value is null)
+                    return;
+                if (value is not IDataProvider)
+                    throw new InvalidOperationException();
+                var constructor = value.GetType().GetConstructor([]);
+                if (!constructor?.IsPublic ?? true)
+                    throw new InvalidOperationException();
+                Provider_ = value;
+            }
+        }
+
+        public HtmlNode? ResolveNode(HtmlDocument doc) {
+            if (XPath is not null)
+                return doc.DocumentNode.SelectSingleNode(XPath);
+            if (CssPath is not null)
+                return doc.DocumentNode.ThenByClasses(CssPath.Split('/'));
+            if (Provider is not null)
+                return Provider.GetNode(doc);
+            return null;
+        }
+
+        public string ResolveString(HtmlDocument doc) {
+            if (XPath is not null)
+                return doc.DocumentNode.SelectSingleNode(XPath)?.InnerText ?? "";
+            if (CssPath is not null)
+                return doc.DocumentNode.ThenByClasses(CssPath.Split('/'))?.InnerText ?? "";
+            if (Provider is not null)
+                return Provider.Get(doc);
+            return "";
+        }
+
+        public string[] ResolveArray(HtmlDocument doc) {
+            if (Type is not BindingType.Array)
+                return [];
+            var str = ResolveString(doc);
+            return str.Split(ArrayDelimiters);
+        }
+
+        public dynamic? Resolve(HtmlDocument doc) => Type switch {
+            BindingType.Single => ResolveString(doc),
+            BindingType.Array => ResolveArray(doc),
+            BindingType.UseProvider => Provider?.Get(doc),
+            _ => null
+        };
+    }
+}