using System;
using System.Collections.Concurrent;
using FormulaEnginePoC.FormulaEngine.Mapping;

namespace FormulaEnginePoC.FormulaEngine
{
    public abstract class Formula
    {
        private static readonly ConcurrentDictionary<Type, TypeMapping> CachedTypeMapping = new ConcurrentDictionary<Type, TypeMapping>();

        public string UserExpression { get; }
        public string CodeExpression { get; }

        public Formula(string userExpression, Type mappingType)
        {
            if (false == CachedTypeMapping.TryGetValue(mappingType, out var mapping))
            {
                mapping = new TypeMapping(mappingType);
                CachedTypeMapping[mappingType] = mapping;
            }

            UserExpression = userExpression;
            CodeExpression = FormulaConverter.Convert(UserExpression, mapping);
        }

        public abstract void Compile();
    }
}