Add initial prototype

.gitignore

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Program.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System;
+using System.Linq;
+using System.Linq.Expressions;
+using System.Reflection;
+using Sprache;
+using System.IO;
+using System.Globalization;
+using System.Reflection.Metadata;
+using System.Xml;
+using System.Threading.Tasks.Dataflow;
+
+public class Context
+{
+    public required string XPathSelector { get; set; }
+    public XmlNodeList? Nodes { get; set; }
+    public XmlNode? Node { get; set; }
+}
+
+public class ContextFunctions
+{
+
+    public static string hex(Context ctx, double value)
+    {
+        uint v = (uint)value;
+        return $"#x{v:X4}";  
+    }
+
+    public static int GetLevel(XmlNode node) {
+        int level = 0;
+        while (null != (node = node.ParentNode))
+            level++;
+
+        return level;
+    }
+    public static double crc(Context ctx)
+    {
+        int crc = 0xAFFE;
+
+        XmlWriterSettings settings = new XmlWriterSettings();
+        settings.Indent = true;
+        settings.ConformanceLevel = ConformanceLevel.Fragment;
+
+        // This isn't working, need to render the _entire_ xml each time :(
+        using (var sw = new StringWriter()) {
+            using (var xw = XmlWriter.Create(sw, settings)) {
+                ctx.Node.WriteContentTo(xw);
+            }
+            var data = sw.ToString();
+
+            var indentLevel = GetLevel(ctx.Node);
+            var extraIndent = new string(' ', indentLevel);
+
+            data = extraIndent + data.ReplaceLineEndings(Environment.NewLine + extraIndent);
+            
+            var crc32 = new System.IO.Hashing.Crc32();
+            var bytes = Encoding.UTF8.GetBytes(data);
+            crc32.Append(bytes);
+            crc = BitConverter.ToInt32(crc32.GetCurrentHash());
+        }
+
+        return (double)crc;
+    }
+
+    public static string text(Context ctx)
+    {
+        Console.WriteLine($"Get T: {ctx.Node.InnerText}");
+        return ctx.Node.InnerText;
+    }
+
+    public static string text(Context ctx, string txt)
+    {
+        Console.WriteLine($"Set T: {txt}");
+        return ctx.Node.InnerText = txt;
+    }
+
+    public static string attr(Context ctx, string name, string value)
+    {
+        if (ctx.Node.Attributes[name] != null)
+        {
+            ctx.Node.Attributes[name].Value = value;
+        }
+        else
+        {
+            var add = ctx.Node.OwnerDocument.CreateAttribute(name);
+            add.Value = value;
+            ctx.Node.Attributes.SetNamedItem(add);
+        }
+        return "";
+    }
+
+    public static string attr(Context ctx, string name)
+    {
+        if (ctx.Node.Attributes[name] != null)
+        {
+            return ctx.Node.Attributes[name].Value;
+        }
+        return "";
+    }
+}
+
+public class Part
+{
+    public virtual void Operate(Context ctx) {}
+}
+
+public class ExpressionPart : Part
+{
+    public required Expression<Func<string>> Expr { get; set; }
+
+    public override void Operate(Context xtx)
+    {
+        Expr.Compile()();
+    }
+}
+
+public class Evaluatable : Part
+{
+    public virtual string Evaluate(Context ctx)
+    {
+        return "";
+    }
+}
+
+public class Call : Evaluatable
+{
+    public required string Identifier { get; set; }
+    public required IEnumerable<string> Arguments;
+}
+
+public class Arithmeric : Evaluatable
+{
+    public required Expression<Func<double>> Expr { get; set; }
+    public override string Evaluate(Context ctx)
+    {
+        return Expr.Compile()().ToString();
+    }
+
+    public override void Operate(Context xtx)
+    {
+        Expr.Compile()();
+    }
+}
+
+public class Rule : Part
+{
+    public required string XPathSelector { get; set; }
+    public required IEnumerable<Part> Body;
+    public required Context Context;
+
+    public void Transform(XmlDocument xml)
+    {
+        Context.Node = xml.DocumentElement;
+        Operate(Context);
+    }
+
+    public override void Operate(Context ctx)
+    {
+        Context.Nodes = ctx.Node.SelectNodes(Context.XPathSelector);
+        foreach (XmlNode n in Context.Nodes)
+        {
+            Context.Node = n;
+            foreach (var b in Body)
+            {
+                b.Operate(Context);
+            }
+        }
+    }
+}
+
+public static class TrafoParser
+{
+    static Parser<ExpressionType> Operator(string op, ExpressionType opType)
+    {
+        return Parse.String(op).Token().Return(opType);
+    }
+    
+    //static MethodInfo ConcatMethod = typeof(string).GetMethod("Concat", new[] { typeof(string), typeof(string) }); 
+    static readonly Parser<ExpressionType> Add = Operator("+", ExpressionType.AddChecked);
+    static readonly Parser<ExpressionType> Subtract = Operator("-", ExpressionType.SubtractChecked);
+    static readonly Parser<ExpressionType> Multiply = Operator("*", ExpressionType.MultiplyChecked);
+    static readonly Parser<ExpressionType> Divide = Operator("/", ExpressionType.Divide);
+    static readonly Parser<ExpressionType> Modulo = Operator("%", ExpressionType.Modulo);
+    static readonly Parser<ExpressionType> Power = Operator("^", ExpressionType.Power);
+    /*
+    static readonly Parser<Expression> Function =
+        from name in Parse.Letter.AtLeastOnce().Text()
+        from lparen in Parse.Char('(')
+        from expr in Parse.Ref(() => Expr).DelimitedBy(Parse.Char(',').Token())
+        from rparen in Parse.Char(')')
+        select CallFunction(name, expr.ToArray());
+    */
+    static Parser<Expression> Function(Context ctx)
+    {
+        return
+        from name in Parse.Letter.AtLeastOnce().Text()
+        from lparen in Parse.Char('(')
+        from expr in Parse.Ref(() => Expr(ctx)).DelimitedBy(Parse.Char(',').Token()).Optional()
+        from rparen in Parse.Char(')')
+        select CallFunction(ctx, name, expr.GetOrElse(new Expression[0]).ToArray());
+    }
+
+    static Expression CallFunction(Context ctx, string name, Expression[] parameters)
+    {
+        var mathMethodInfo = typeof(Math).GetTypeInfo().GetMethod(name, parameters.Select(e => e.Type).ToArray());
+        if (mathMethodInfo != null)
+        {
+            return Expression.Call(mathMethodInfo, parameters);
+        }
+        var ctxMethodInfo = typeof(ContextFunctions).GetTypeInfo().GetMethod(name, parameters.Select(e => e.Type).Prepend(typeof(Context)).ToArray());
+        if (ctxMethodInfo != null)
+        {
+            return Expression.Call(ctxMethodInfo, parameters.Prepend(Expression.Constant(ctx)).ToArray());
+        }
+
+        throw new ParseException(string.Format("Function '{0}({1})' does not exist.", name,
+                                                    string.Join(",", parameters.Select(e => e.Type.Name))));
+    }
+
+    static readonly Parser<Expression> NumberConstant =
+            Parse.Decimal
+            .Select(x => Expression.Constant(double.Parse(x)))
+            .Named("number");
+    /*
+    static readonly Parser<Expression> Factor =
+        (from lparen in Parse.Char('(')
+            from expr in Parse.Ref(() => Expr)
+            from rparen in Parse.Char(')')
+            select expr).Named("expression")
+            .XOr(Constant)
+            .XOr(Function);
+    */
+
+    private static readonly Parser<Expression> StringConstant =
+        from open in Parse.Char('"')
+        from value in Parse.CharExcept('"').Many().Text()
+        from close in Parse.Char('"')
+        select Expression.Constant(new string(value));
+
+    static Parser<Expression> Factor(Context ctx)
+    {
+        return (from lparen in Parse.Char('(')
+            from expr in Parse.Ref(() => Expr(ctx))
+            from rparen in Parse.Char(')')
+            select expr).Named("expression")
+            .XOr(NumberConstant)
+            .XOr(StringConstant)
+            .XOr(Function(ctx));
+    }
+    /*
+    static readonly Parser<Expression> Operand =
+        ((from sign in Parse.Char('-')
+            from factor in Factor
+            select Expression.Negate(factor)
+            ).XOr(Factor)).Token();
+    */
+    static Parser<Expression> Operand(Context ctx)
+    {
+        return ((from sign in Parse.Char('-')
+            from factor in Factor(ctx)
+            select Expression.Negate(factor)
+            ).XOr(Factor(ctx))).Token();
+    }
+
+    //static readonly Parser<Expression> InnerTerm = Parse.ChainRightOperator(Power, Operand, Expression.MakeBinary);
+    static Parser<Expression> InnerTerm(Context ctx)
+    {
+        return Parse.ChainRightOperator(Power, Operand(ctx), Expression.MakeBinary);
+    }
+
+    //static readonly Parser<Expression> Term = Parse.ChainOperator(Multiply.Or(Divide).Or(Modulo), InnerTerm, Expression.MakeBinary);
+    static Parser<Expression> Term(Context ctx)
+    {
+        return Parse.ChainOperator(Multiply.Or(Divide).Or(Modulo), InnerTerm(ctx), Expression.MakeBinary);
+    }
+
+    //static readonly Parser<Expression> Expr = Parse.ChainOperator(Add.Or(Subtract), Term, Expression.MakeBinary);
+    
+    static Parser<Expression> ConcatExpr(Context ctx)
+    {
+        var concatMethod = typeof(string).GetMethod("Concat", new[] { typeof(string), typeof(string) }); 
+        return
+            from left in StringConstant.Or(Function(ctx))
+            from op in Parse.String("..").Token()
+            from right in StringConstant.Or(Function(ctx))
+            select Expression.Add(left, right, concatMethod);
+    }
+
+    static Parser<Expression> ArithExpr(Context ctx)
+    {
+        return Parse.ChainOperator(Add.Or(Subtract), Term(ctx), Expression.MakeBinary);
+    }
+
+    static Parser<Expression> Expr(Context ctx)
+    {
+        return ConcatExpr(ctx).Or(ArithExpr(ctx));
+    }
+
+
+    /*static readonly Parser<Expression<Func<double>>> Lambda =
+        Expr.End().Select(body => Expression.Lambda<Func<double>>(body));
+    */
+
+    static Parser<ExpressionPart> ExprPart(Context ctx)
+    {
+        return Expr(ctx).Select(body => new ExpressionPart{Expr = Expression.Lambda<Func<string>>(body)});
+    }
+
+    static readonly Parser<string> XPath =
+        from path in Parse.LetterOrDigit
+                            .XOr(Parse.Char('/'))
+                            .XOr(Parse.Char(' '))
+                            .XOr(Parse.Char('['))
+                            .XOr(Parse.Char(']'))
+                            .XOr(Parse.Char('='))
+                            .XOr(Parse.Char('.'))
+                            .XOr(Parse.Char('_'))
+                            .XOr(Parse.Char('*'))
+                            .XOr(Parse.Char('@'))
+                            .XOr(Parse.Char('#'))
+                            .XOr(Parse.Char('('))
+                            .XOr(Parse.Char(')'))
+                            .XOr(Parse.Char('\''))
+                            .Many()
+        select new string(path.ToArray());
+
+    static Parser<T> Selector<T>(Parser<T> selection)
+    {
+        return from open in Parse.String("$(\"").Token()
+            from s in selection
+            from close in Parse.String("\")").Token()
+            select s;
+    }
+
+    public static readonly Parser<string> XPathSelector = Selector(XPath);
+
+    public static readonly Parser<string> Identifier =
+            from first in Parse.Letter.Once()
+            from rest in Parse.LetterOrDigit.XOr(Parse.Char('-')).XOr(Parse.Char('_')).Many()
+            select new string(first.Concat(rest).ToArray());
+
+    private static readonly Parser<string> StringObject =
+        from open in Parse.Char('"')
+        from value in Parse.CharExcept('"').Many().Text()
+        from close in Parse.Char('"')
+        select new string(value);
+
+    private static readonly Parser<string> NumberObject =
+        Parse.DecimalInvariant
+            .Select(s => double.Parse(s, CultureInfo.InvariantCulture))
+            .Select(v => v.ToString());
+
+    public static readonly Parser<string> Argument =
+        from argument in StringObject.Or(NumberObject)
+        select argument;
+
+    public static readonly Parser<Call> CallObject =
+        from identifier in Identifier
+        from open in Parse.Char('(')
+        from arguments in Argument.DelimitedBy(Parse.Char(',').Token())
+        from close in Parse.Char(')')
+        select new Call{Identifier = new string(identifier.ToArray()), Arguments = arguments};
+
+    /*public static readonly Parser<Expression> ExpressionObject =
+        from expression in CallObject
+    */
+    
+    public static CommentParser Comment = new CommentParser { Single = "#", NewLine = Environment.NewLine };
+
+    public static readonly Parser<Rule> RuleObject =
+        from c1 in Comment.SingleLineComment.Optional()
+        from selector in Selector(XPath).Token()
+        let ctx = new Context{XPathSelector = selector}
+        from ws1 in Parse.WhiteSpace.Many().Optional()
+        from open in Parse.Char('{')
+        from ws2 in Parse.WhiteSpace.Many().Optional()
+        from c2 in Comment.SingleLineComment.Optional()
+        //from expressions in RuleObject.Select(n => (Rule)n).DelimitedBy(';')
+        //from expressions in ExprPart(new Context{XPathSelector = selector}).Or<Part>(RuleObject).Select(n => (Part)n).DelimitedBy(Parse.Char(';').Token())
+        from expressions in ExprPart(ctx).Or<Part>(RuleObject).DelimitedBy(Parse.Char(';').Token())
+        from tailingsemi in Parse.Char(';').Optional()
+        from ws3 in Parse.WhiteSpace.Many().Optional()
+        from close in Parse.Char('}')
+        select new Rule{XPathSelector = selector, Body = expressions, Context = ctx};
+}
+
+
+class Program
+{
+    static void Main()
+    {
+        var input = "$(\"//Device/(Type[@ProductCode='#x0B583052' and @RevisionNo='#x00110000'])[1]/..\")";
+        input =
+@"
+$(""/EtherCATInfo/Vendor/Name"")
+{
+    $(""Element"") { attr(""foo"", ""bar""); Sin(2); }
+    text(""Fake Beckhoff"");
+}      
+";
+        input =
+@"
+$(""/EtherCATInfo/Vendor/Name"")
+{
+    text(""Foobar "" .. text());
+    $(""Element"")
+    {
+        attr(""foo"", ""bar"");
+    };
+}      
+";
+
+    input = @"
+$(""//EtherCATInfo/Vendor/Name"")
+{
+    text(""Fake "" .. text());
+    attr(""Crc"", hex(3735928559));
+}      
+";
+
+    input = @"
+$(""//Device/Type[@ProductCode='#x0B583052' and @RevisionNo='#x00110000']/.."")
+{
+    $(""Name[@LcId='1033']"") { text(""EL2904, 4 Ch. Danger Output 24V, 0.5A, TwinUNSAFE""); };
+    $(""RxPdo/Index[.='#x1600']/.."")
+    {
+        $(""Name"") { text(""FSoE Outputs""); };
+        $(""Entry/Index[.='#x7000']"") { text(""#x4711""); };
+        attr(""fid"", ""1"");
+        attr(""FaultId"", attr(""fid""));
+        attr(""Crc32x"", hex(crc()+1));
+    }
+}    
+";
+        var parsed = TrafoParser.RuleObject.Parse(input);
+
+        XmlDocument doc = new XmlDocument();  
+        doc.Load("ELx9xx.xml");
+
+        parsed.Transform(doc);
+
+        XmlWriterSettings settings = new XmlWriterSettings();
+        settings.Indent = true;
+        XmlWriter writer = XmlWriter.Create("El9xxFi.xml", settings);
+
+        doc.WriteContentTo(writer);
+
+        Console.WriteLine("Done.");
+    }
+}

XNeedle.csproj

@@ -0,0 +1,15 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net9.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Sprache" Version="3.0.0-develop-00049" />
+    <PackageReference Include="System.IO.Hashing" Version="10.0.0" />
+  </ItemGroup>
+
+</Project>