AyCode.Blazor/AyCode.Blazor.Components/Services/ExpressionHelpers/AcExpressionNode.cs

using System.Linq.Expressions;
using System.Text.Json.Serialization;

namespace AyCode.Blazor.Components.Services.ExpressionHelpers;

/// <summary>
/// Universal DTO representing any Expression node.
/// Recursively represents the entire Expression tree.
/// Serializable to JSON for transport over SignalR or HTTP.
/// </summary>
public sealed class AcExpressionNode
{
    /// <summary>
    /// The expression node type (Add, Equal, Call, MemberAccess, Lambda, etc.)
    /// </summary>
    public ExpressionType NodeType { get; set; }

    /// <summary>
    /// The CLR type name of this expression's result.
    /// </summary>
    public string? TypeName { get; set; }

    #region Binary Expressions (Add, Equal, AndAlso, OrElse, etc.)

    /// <summary>
    /// Left operand for binary expressions.
    /// </summary>
    public AcExpressionNode? Left { get; set; }

    /// <summary>
    /// Right operand for binary expressions.
    /// </summary>
    public AcExpressionNode? Right { get; set; }

    #endregion

    #region Unary Expressions (Not, Convert, Negate, etc.)

    /// <summary>
    /// Operand for unary expressions.
    /// </summary>
    public AcExpressionNode? Operand { get; set; }

    #endregion

    #region Lambda Expressions

    /// <summary>
    /// Body of lambda expression.
    /// </summary>
    public AcExpressionNode? Body { get; set; }

    /// <summary>
    /// Parameter definitions for lambda expressions.
    /// </summary>
    public List<ParameterNode>? Parameters { get; set; }

    #endregion

    #region Member Access

    /// <summary>
    /// Member/property/field name for MemberAccess expressions.
    /// </summary>
    public string? MemberName { get; set; }

    /// <summary>
    /// Object expression for member access or instance method calls.
    /// </summary>
    public AcExpressionNode? Object { get; set; }

    /// <summary>
    /// Declaring type for static members.
    /// </summary>
    public string? DeclaringType { get; set; }

    #endregion

    #region Method Call

    /// <summary>
    /// Method name for Call expressions.
    /// </summary>
    public string? MethodName { get; set; }

    /// <summary>
    /// Arguments for method calls.
    /// </summary>
    public List<AcExpressionNode>? Arguments { get; set; }

    /// <summary>
    /// Generic type arguments for generic method calls.
    /// </summary>
    public List<string>? GenericArguments { get; set; }

    #endregion

    #region Constant

    /// <summary>
    /// Serialized constant value (JSON).
    /// </summary>
    public string? Value { get; set; }

    #endregion

    #region Parameter

    /// <summary>
    /// Parameter name for Parameter expressions.
    /// </summary>
    public string? ParameterName { get; set; }

    /// <summary>
    /// Parameter index (for matching parameters in lambda).
    /// </summary>
    public int? ParameterIndex { get; set; }

    #endregion

    #region Conditional (Ternary)

    /// <summary>
    /// Test expression for conditional expressions.
    /// </summary>
    public AcExpressionNode? Test { get; set; }

    /// <summary>
    /// IfTrue branch for conditional expressions.
    /// </summary>
    public AcExpressionNode? IfTrue { get; set; }

    /// <summary>
    /// IfFalse branch for conditional expressions.
    /// </summary>
    public AcExpressionNode? IfFalse { get; set; }

    #endregion

    #region New Expression

    /// <summary>
    /// Constructor arguments for New expressions.
    /// </summary>
    public List<AcExpressionNode>? ConstructorArguments { get; set; }

    /// <summary>
    /// Member bindings for MemberInit expressions.
    /// </summary>
    public List<MemberBindingNode>? MemberBindings { get; set; }

    #endregion

    #region Array/Collection

    /// <summary>
    /// Elements for NewArrayInit expressions.
    /// </summary>
    public List<AcExpressionNode>? Elements { get; set; }

    #endregion
}

/// <summary>
/// Represents a parameter definition in a lambda expression.
/// </summary>
public sealed class ParameterNode
{
    /// <summary>
    /// Parameter name.
    /// </summary>
    public string Name { get; set; } = "";

    /// <summary>
    /// Parameter type name.
    /// </summary>
    public string TypeName { get; set; } = "";

    /// <summary>
    /// Parameter index in the lambda.
    /// </summary>
    public int Index { get; set; }
}

/// <summary>
/// Represents a member binding in MemberInit expressions.
/// </summary>
public sealed class MemberBindingNode
{
    /// <summary>
    /// The member name being bound.
    /// </summary>
    public string MemberName { get; set; } = "";

    /// <summary>
    /// The binding type (Assignment, MemberBinding, ListBinding).
    /// </summary>
    public MemberBindingType BindingType { get; set; }

    /// <summary>
    /// The expression being assigned (for Assignment bindings).
    /// </summary>
    public AcExpressionNode? Expression { get; set; }

    /// <summary>
    /// Nested bindings (for MemberMemberBinding).
    /// </summary>
    public List<MemberBindingNode>? Bindings { get; set; }

    /// <summary>
    /// Element initializers (for ListBinding).
    /// </summary>
    public List<List<AcExpressionNode>>? Initializers { get; set; }
}