template engine

2026-02-03 14:27:13 +01:00
parent 46b648d753
commit ec5decb12e
31 changed files with 4640 additions and 946 deletions
--- a/Inspectron.Epson.TemplateEngine/DataBinding/DataContext.cs
+++ b/Inspectron.Epson.TemplateEngine/DataBinding/DataContext.cs
@@ -0,0 +1,123 @@
+using System.Text.Json;
+
+namespace Inspectron.Epson.TemplateEngine.DataBinding;
+
+public class DataContext
+{
+    private readonly JsonElement _root;
+    private readonly DataContext? _parent;
+    private readonly Dictionary<string, JsonElement> _variables = new(StringComparer.OrdinalIgnoreCase);
+    private readonly Dictionary<string, object> _loopVariables = new(StringComparer.OrdinalIgnoreCase);
+
+    public DataContext(JsonElement root)
+    {
+        _root = root;
+    }
+
+    private DataContext(JsonElement root, DataContext parent)
+    {
+        _root = root;
+        _parent = parent;
+    }
+
+    public DataContext CreateChildScope()
+    {
+        return new DataContext(_root, this);
+    }
+
+    public void SetVariable(string name, JsonElement value)
+    {
+        _variables[name] = value;
+    }
+
+    public void SetLoopVariable(string name, object value)
+    {
+        _loopVariables[name] = value;
+    }
+
+    public object? GetLoopVariable(string name)
+    {
+        if (_loopVariables.TryGetValue(name, out var value))
+            return value;
+        return _parent?.GetLoopVariable(name);
+    }
+
+    public JsonElement? Resolve(string expression)
+    {
+        if (string.IsNullOrWhiteSpace(expression))
+            return null;
+
+        var parts = expression.Split('.');
+        var firstPart = parts[0];
+
+        // Check local variables first
+        JsonElement? current = null;
+
+        if (_variables.TryGetValue(firstPart, out var varValue))
+        {
+            current = varValue;
+        }
+        else if (_parent != null)
+        {
+            // Walk up scope chain for variables
+            var ctx = _parent;
+            while (ctx != null)
+            {
+                if (ctx._variables.TryGetValue(firstPart, out var parentVar))
+                {
+                    current = parentVar;
+                    break;
+                }
+                ctx = ctx._parent;
+            }
+        }
+
+        // If not found in variables, try root
+        if (current == null)
+        {
+            current = GetProperty(_root, firstPart);
+        }
+
+        if (current == null)
+            return null;
+
+        // Navigate remaining parts
+        for (int i = 1; i < parts.Length; i++)
+        {
+            current = GetProperty(current.Value, parts[i]);
+            if (current == null)
+                return null;
+        }
+
+        return current;
+    }
+
+    private static JsonElement? GetProperty(JsonElement element, string propertyName)
+    {
+        if (element.ValueKind != JsonValueKind.Object)
+            return null;
+
+        // Case-insensitive property lookup
+        foreach (var prop in element.EnumerateObject())
+        {
+            if (string.Equals(prop.Name, propertyName, StringComparison.OrdinalIgnoreCase))
+                return prop.Value;
+        }
+
+        return null;
+    }
+
+    public static string GetStringValue(JsonElement element)
+    {
+        return element.ValueKind switch
+        {
+            JsonValueKind.String => element.GetString() ?? "",
+            JsonValueKind.Number => element.TryGetInt64(out var l) ? l.ToString() : element.GetDouble().ToString(),
+            JsonValueKind.True => "true",
+            JsonValueKind.False => "false",
+            JsonValueKind.Null => "",
+            JsonValueKind.Undefined => "",
+            _ => element.GetRawText()
+        };
+    }
+}