using CppAst;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace refl
{
    internal class OverTree
    {
        public const int PrefixSize = 6;
        List<int> Ctors = new List<int>();
        List<int> Funcs = new List<int>();
        private bool isInit = false;
        public OverTree() { }
        public void Init(CppClass cppClass)
        {
            if (isInit)
            {
                return;
            }
            isInit = true;
            foreach (var types in cppClass.Typedefs)
            {
                string key = types.Name.Substring(0, PrefixSize);
                if(key == "__Ctor")
                {
                    Ctors.Add(int.Parse(types.Name.Substring(PrefixSize)));
                }
                else if(key == "__Func")
                {
                    Funcs.Add(int.Parse(types.Name.Substring(PrefixSize)));
                }
            }
            Ctors.Sort();
            Funcs.Sort();
        }
        public void Clear()
        {
            Ctors.Clear();
            Funcs.Clear();
            isInit = false;
        }
        public string Find(string name)
        {
            string key = name.Substring(0, PrefixSize);
            int v = int.Parse(name.Substring(PrefixSize));
            if (key == "__Ctor")
            {
                v = FindValue(Ctors, v);
            }
            else
            {
                v = FindValue(Funcs, v);
            }
            return key + v;
        }
        private static int FindValue(List<int> sortedNumbers, int target)
        {
            if(sortedNumbers.Count == 0)
            {
                return target;
            }
            int index = sortedNumbers.BinarySearch(target);
            if(index < 0)
            {
                index = ~index;
            }
            index = index > 0 ? index - 1 : 0;
            return sortedNumbers[index];
        }
    }
}