using System;
using System.Collections.Generic;

namespace ShrinkModFramework
{
    public sealed class ShrinkModRegistryManager
    {
        private readonly Dictionary<string, object> _registries = new();

        public IReadOnlyShrinkModRegistry<T> GetOrCreateRegistry<T>(string name) =>
            GetOrCreateMutableRegistry<T>(name);

        internal ShrinkModRegistry<T> GetOrCreateMutableRegistry<T>(string name)
        {
            var compositeKey = BuildCompositeKey(typeof(T), name);
            if (_registries.TryGetValue(compositeKey, out var existing))
                return (ShrinkModRegistry<T>)existing;

            var registry = new ShrinkModRegistry<T>(name);
            _registries.Add(compositeKey, registry);
            return registry;
        }

        public bool TryGetRegistry<T>(string name, out IReadOnlyShrinkModRegistry<T> registry)
        {
            var compositeKey = BuildCompositeKey(typeof(T), name);
            if (_registries.TryGetValue(compositeKey, out var existing))
            {
                registry = (ShrinkModRegistry<T>)existing;
                return true;
            }

            registry = null;
            return false;
        }

        internal void Clear() => _registries.Clear();

        internal void RemoveOwnedEntries(string ownerModId)
        {
            foreach (var registry in _registries.Values)
            {
                if (registry is IShrinkOwnedRegistry ownedRegistry)
                    ownedRegistry.RemoveOwnedEntries(ownerModId);
            }
        }

        private static string BuildCompositeKey(Type type, string name)
        {
            if (string.IsNullOrWhiteSpace(name))
                throw new ArgumentException("注册表名称不能为空。", nameof(name));

            return $"{type.AssemblyQualifiedName}::{name.Trim()}";
        }
    }
}