using InABox.Core;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Text;

namespace InABox.Configuration
{
    public class SubConfiguration<T, TParent> : IConfiguration<T>
        where TParent : new()
    {
        public IConfiguration<TParent> Configuration { get; set; }

        private Func<TParent, T> Getter { get; set; }
        private Action<TParent, T> Setter { get; set; }

        public SubConfiguration(IConfiguration<TParent> configuration, Expression<Func<TParent, T>> expression)
        {
            Configuration = configuration;

            var property = CoreUtils.GetFullPropertyName(expression, ".");
            Getter = Expressions.Getter(expression);
            var setter = Expressions.Setter<TParent>(property);
            Setter = (parent, value) => setter(parent, value);
        }

        public string[] Sections() => Configuration.Sections();

        public T Load(bool useCache = true)
        {
            var parent = Configuration.Load(useCache);
            return Getter(parent);
        }

        public Dictionary<string, T> LoadAll(IEnumerable<string>? keys = null)
        {
            var parent = Configuration.LoadAll(keys);
            return parent.ToDictionary(x => x.Key, x => Getter(x.Value));
        }

        public void Save(T obj)
        {
            var parent = Configuration.Load(true);
            Setter(parent, obj);
            Configuration.Save(parent);
        }

        public void SaveAll(Dictionary<string, T> objs, bool reset = false)
        {
            var parents = Configuration.LoadAll(objs.Keys);
            foreach(var (key, obj) in objs)
            {
                var parent = parents.GetValueOrAdd(key);
                Setter(parent, obj);
            }
            Configuration.SaveAll(parents);
        }

        public void Delete(Action<Exception?>? callback = null)
        {
            var parent = Configuration.Load(true);
            Setter(parent, default);
            Configuration.Save(parent);
        }
    }
}