using System.ComponentModel;
using System.Linq.Expressions;
using System.Reflection;

namespace BlazorEditForms.Binding;

public static class PropertyBinding
{
    public static PropertyBinding<TProperty> Create<TProperty>(Expression<Func<TProperty>> prop)
    {
        if (prop.Body is not MemberExpression memberExpression)
        {
            throw new Exception($"Expected expression Body to be a member expression, but got {prop.Body.GetType()}");
        }
        return new PropertyBinding<TProperty>(memberExpression);
    }
}

public class PropertyBinding<TProperty> : IBinding<TProperty>, IBindingMetadata, IBindingValue<TProperty>, IMemberExpressionBinding<TProperty>
{
    private readonly Func<TProperty> _getter;
    private readonly Action<TProperty> _setter;

    public Expression<Func<TProperty>> Expression { get; }

    public string DisplayName { get; }

    public PropertyBinding(MemberExpression memberExpression)
    {
        Expression = ExpressionBuilder.CreateGetter<TProperty>(memberExpression);
        _getter = Expression.Compile();
        _setter = ExpressionBuilder.CreateSetter<TProperty>(memberExpression).Compile();

        var displayAttr = memberExpression.Member.GetCustomAttributes<DisplayNameAttribute>().FirstOrDefault();
        DisplayName = displayAttr?.DisplayName ?? "<Unknown>";
    }

    public TProperty Get() => _getter();
    public void Set(TProperty value) => _setter(value);
}