using Microsoft.Extensions.Configuration;
using MP.Core.DTO;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Threading.Tasks;

namespace MP.Data.Services.RouteWeight
{
    public class InMemoryWeightProvider : IWeightProvider
    {
        #region Public Constructors

        public InMemoryWeightProvider(IConfiguration config)
        {
            _defaultOld = config.GetValue<int>("RouteMan:DefaultWeightOld", 100);
            _defaultNew = config.GetValue<int>("RouteMan:DefaultWeightNew", 0);
        }

        #endregion Public Constructors

        #region Public Methods

        public async Task<List<WeightDTO>> GetAllWeightsAsync()
        {
            var result = new List<WeightDTO>();
            await Task.Delay(1);

            foreach (var kvp in _map)
            {
                result.Add(new WeightDTO
                {
                    Method = kvp.Key,
                    OldWeight = Math.Clamp(kvp.Value.oldW, 0, 100),
                    NewWeight = Math.Clamp(kvp.Value.newW, 0, 100)
                });
            }
            return result;
        }

        public (int oldWeight, int newWeight) GetWeightsFor(string method)
        {
            if (string.IsNullOrEmpty(method)) method = "unknown";
            return _map.GetOrAdd(method, _ => (_defaultOld, _defaultNew));
        }

        public void SetWeights(string method, int oldWeight, int newWeight)
        {
            _map[method] = (Math.Clamp(oldWeight, 0, 100), Math.Clamp(newWeight, 0, 100));
        }

        public bool UpsertWeight(WeightDTO updRecord)
        {
            if (updRecord == null || string.IsNullOrEmpty(updRecord.Method))
                return false;

            _map[updRecord.Method] = (Math.Clamp(updRecord.OldWeight, 0, 100), Math.Clamp(updRecord.NewWeight, 0, 100));

            return true;
        }

        #endregion Public Methods

        #region Private Fields

        private readonly int _defaultNew;
        private readonly int _defaultOld;
        private readonly ConcurrentDictionary<string, (int oldW, int newW)> _map = new();

        #endregion Private Fields
    }
}