CliFx/CliFx.Analyzers/ObjectModel/CommandParameterSymbol.cs

using System.Collections.Generic;
using System.Linq;
using CliFx.Analyzers.Utils.Extensions;
using Microsoft.CodeAnalysis;

namespace CliFx.Analyzers.ObjectModel;

internal partial class CommandParameterSymbol
{
    public int Order { get; }

    public string? Name { get; }

    public bool? IsRequired { get; }

    public ITypeSymbol? ConverterType { get; }

    public IReadOnlyList<ITypeSymbol> ValidatorTypes { get; }

    public CommandParameterSymbol(
        int order,
        string? name,
        bool? isRequired,
        ITypeSymbol? converterType,
        IReadOnlyList<ITypeSymbol> validatorTypes)
    {
        Order = order;
        Name = name;
        IsRequired = isRequired;
        ConverterType = converterType;
        ValidatorTypes = validatorTypes;
    }
}

internal partial class CommandParameterSymbol
{
    private static AttributeData? TryGetParameterAttribute(IPropertySymbol property) =>
        property
            .GetAttributes()
            .FirstOrDefault(a => a.AttributeClass.DisplayNameMatches(SymbolNames.CliFxCommandParameterAttribute));

    private static CommandParameterSymbol FromAttribute(AttributeData attribute)
    {
        var order = (int)attribute
            .ConstructorArguments
            .Select(a => a.Value)
            .First()!;

        var name = attribute
            .NamedArguments
            .Where(a => a.Key == "Name")
            .Select(a => a.Value.Value)
            .FirstOrDefault() as string;

        var isRequired = attribute
            .NamedArguments
            .Where(a => a.Key == "IsRequired")
            .Select(a => a.Value.Value)
            .FirstOrDefault() as bool?;

        var converter = attribute
            .NamedArguments
            .Where(a => a.Key == "Converter")
            .Select(a => a.Value.Value)
            .Cast<ITypeSymbol?>()
            .FirstOrDefault();

        var validators = attribute
            .NamedArguments
            .Where(a => a.Key == "Validators")
            .SelectMany(a => a.Value.Values)
            .Select(c => c.Value)
            .Cast<ITypeSymbol>()
            .ToArray();

        return new CommandParameterSymbol(order, name, isRequired, converter, validators);
    }

    public static CommandParameterSymbol? TryResolve(IPropertySymbol property)
    {
        var attribute = TryGetParameterAttribute(property);

        return attribute is not null
            ? FromAttribute(attribute)
            : null;
    }

    public static bool IsParameterProperty(IPropertySymbol property) =>
        TryGetParameterAttribute(property) is not null;
}