using System;
using System.Reflection;
using Svrnty.CQRS.Abstractions.Attributes;

namespace Svrnty.CQRS.Abstractions.Discovery;

public class QueryMeta : IQueryMeta
{
    private readonly string _name;

    public QueryMeta(Type queryType, Type serviceType, Type queryResultType)
    {
        QueryType = queryType;
        ServiceType = serviceType;
        QueryResultType = queryResultType;

        // Cache reflection and computed value once in constructor
        var nameAttribute = queryType.GetCustomAttribute<QueryNameAttribute>();
        _name = nameAttribute?.Name ?? queryType.Name.Replace("Query", string.Empty);
    }

    public virtual string Name => _name;

    public virtual Type QueryType { get; }
    public virtual Type ServiceType { get; }
    public virtual Type QueryResultType { get; }
    public virtual string Category => "BasicQuery";

    public string LowerCamelCaseName
    {
        get
        {
            // Use virtual Name property so derived classes can override
            var name = Name;
            if (string.IsNullOrEmpty(name))
                return name;

            var firstLetter = char.ToLowerInvariant(name[0]);
            return $"{firstLetter}{name[1..]}";
        }
    }
}