BadLinqCommon.cs

Go to the documentation of this file.

using System.Collections;
 
using BadScript2.Parser;
using BadScript2.Parser.Expressions;
using BadScript2.Parser.Operators;
using BadScript2.Reader;
using BadScript2.Runtime;
using BadScript2.Runtime.Interop.Reflection.Objects;
using BadScript2.Runtime.Objects;
using BadScript2.Runtime.Objects.Native;
 
namespace BadScript2.Utility.Linq;
 
internal static class BadLinqCommon
{
    public static readonly BadExecutionContextOptions PredicateContextOptions = new BadExecutionContextOptions();
 
    public static (string varName, string query) ParsePredicate(string query)
    {
        string[] parts = query.Split(
            new[]
            {
                "=>",
            },
            StringSplitOptions.RemoveEmptyEntries
        );
        string varName = parts[0].Trim();
        string queryStr = parts[1].Trim();
 
        return (varName, queryStr);
    }
 
    public static bool InnerWhere(string varName, BadExpression query, object? o)
    {
        BadExecutionContext ctx = PredicateContextOptions.Build();
 
        if (o is BadObject bo)
        {
            ctx.Scope.DefineVariable(varName, bo);
        }
        else
        {
            ctx.Scope.DefineVariable(varName, BadObject.CanWrap(o) ? BadObject.Wrap(o) : new BadReflectedObject(o!));
        }
 
        BadObject r = BadObject.Null;
 
        foreach (BadObject o1 in query.Execute(ctx))
        {
            r = o1;
        }
 
        r = r.Dereference();
 
        if (r is not IBadBoolean b)
        {
            throw new Exception($"Error in LINQ Where: {varName} => {query} : {r.ToSafeString()} is not a boolean");
        }
 
        return b.Value;
    }
 
    public static object?[] ToArray(this IEnumerable enumerable)
    {
        return Enumerable.ToArray(enumerable.Cast<object?>());
    }
 
    public static IEnumerable<BadExpression> Parse(string src)
    {
        return new BadSourceParser(new BadSourceReader("<nofile>", src + ';'), BadOperatorTable.Instance).Parse();
    }
}