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




namespace ServerCore;

public static class RandomHelper
{
    // 만분율을 기본 비율단위로 사용 한다 !!!
    public static readonly Int32 DefaultRatio = 10000;
    private static Random random = new Random((int)DateTimeHelper.Current.Ticks);

    public static double nextDouble(double min, double max)
    {
        return random.NextDouble() * (max - min) + min;
    }

    public static double rangeDouble(double min, double max)
    {
        return random.NextDouble() * (max - min) + min;
    }

    public static string randomString(Int32 length)
    {
        const string chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
        return new string(Enumerable.Repeat(chars, length).Select(s => s[random.Next(s.Length)]).ToArray());
    }

    public static string randomName(Int32 length)
    {
        string[] consonants = { "b", "c", "d", "f", "g", "h", "j", "k", "l", "m", "n", "p", "q", "r", "s", "sh", "zh", "t", "v", "w", "x", "z" };
        string[] vowels = { "a", "e", "i", "o", "u", "ae", "y" };
        StringBuilder Name = new StringBuilder();
        Name.Append(consonants[random.Next(consonants.Length)].ToUpper());
        Name.Append(vowels[random.Next(vowels.Length)]);
        Int32 idx = 2;
        while (idx < length)
        {
            Name.Append(consonants[random.Next(consonants.Length)]);
            Name.Append(vowels[random.Next(vowels.Length)]);
            idx += 2;
            if (length - idx == 1)
            {
                Name.Append(consonants[random.Next(consonants.Length)]);
                ++idx;
            }
        }
        return Name.ToString();
    }

    public static Int32 number(Int32 max)
    {
        Int32 val = random.Next(0, max);
        return val;
    }

    public static Int32 range(Int32 min, Int32 max)
    {
        Int32 val = random.Next(min, max);
        return val;
    }
    // 만분율 기반 확률 계산
    public static bool defaultProb(Int32 target_prob)
    {
        Int32 prob = random.Next(1, (Int32)DefaultRatio + 1);

        return prob < target_prob;
    }
    // 만분율 기반 확률 계산
    public static bool defaultProb(Int64 target_prob)
    {
        return defaultProb((Int32)target_prob);
    }
    // min 과 max를 포함한 사잇값
    public static Int32 between(Int32 min, Int32 max)
    {
        return random.Next(min, max + 1);
    }

    public static Int32 between(Int64 min, Int64 max)
    {
        return random.Next((Int32)min, (Int32)max + 1);
    }

    public static Int32 next()
    {
        return random.Next();
    }

    public static Int32 next(Int32 min, Int32 max)
    {
        return random.Next(min, max);
    }

    public static float next(float min, float max)
    {
        Int32 min_int = (Int32)(min * DefaultRatio);
        Int32 max_int = (Int32)(max * DefaultRatio);

        return (float)(between(min_int, max_int) / DefaultRatio);
    }

    public static Int32 next(Int32 max)
    {
        return random.Next(max);
    }

    public static void shuffleList<T>(IList<T> list)
    {
        Int32 count = list.Count;
        while (count > 1)
        {
            Int32 key = random.Next(count);
            T value = list[key];
            list[key] = list[count - 1];
            list[count - 1] = value;

            count--;
        }
    }

    public static List<Int32> randomIndex(Int32 count)
    {
        List<Int32> index_list = new List<Int32>();
        for (Int32 i = 0; i < count; ++i)
        {
            index_list.Add(i);
        }

        shuffleList<Int32>(index_list);
        return index_list;
    }

    public static Vector3 randomPointInCicle(Vector3 centerPos, float radius)
    {
        var angle = random.NextDouble() * Math.PI * 2;
        var rad = random.NextDouble() * radius;

        float x = (float)(centerPos.X + rad * Math.Cos(angle));
        float z = (float)(centerPos.Z + rad * Math.Sin(angle));

        return new Vector3(x, centerPos.Y, z);
    }

    public static Vector3 randomPointInFanShape(Vector3 centerPos, float radius, float degree)
    {
        var angle = degree * MathHelper.Deg2Rad;
        var rad = random.NextDouble() * radius;

        float x = (float)(centerPos.X + rad * Math.Cos(angle));
        float z = (float)(centerPos.Z + rad * Math.Sin(angle));

        return new Vector3(x, centerPos.Y, z);
    }

    public static Vector3 randomPointInRectangle(Vector3 centerPos, float xScale, float zScale)
    {
        var x = centerPos.X + (float)rangeDouble(centerPos.X - (xScale * 0.5), xScale + (xScale * 0.5));
        var z = centerPos.Z + (float)rangeDouble(centerPos.Z - (zScale * 0.5), zScale + (zScale * 0.5));

        return new Vector3(x, centerPos.Y, z);
    }
}