using System;

namespace ProjectI.Builds
{
    public sealed class UltimateChargeState
    {
        public const float Maximum = 100;
        public float Charge { get; private set; }
        public double ActiveUntil { get; private set; }
        private double lastTick = double.NaN;
        private bool wasEligible;
        public void Tick(double now, bool eligible)
        {
            if (!Finite(now) || (!double.IsNaN(lastTick) && now < lastTick)) return;
            if (!double.IsNaN(lastTick) && eligible && wasEligible)
                Add((float)(Math.Max(0, now - Math.Max(lastTick, ActiveUntil)) * .5));
            lastTick = now;
            wasEligible = eligible;
        }
        public void AddDamage(float applied, bool ultimate)
        { if (!ultimate && applied > 0 && !float.IsNaN(applied) && !float.IsInfinity(applied)) Add(applied * .01f); }
        public void AddKill(bool elite, bool boss, bool ultimate)
        { if (!ultimate) Add(boss ? 10 : elite ? 5 : 2); }
        public bool TryConsume(double now, double duration)
        {
            if (!Finite(now) || !Finite(duration) || double.IsInfinity(now + duration) || Charge < Maximum || now < ActiveUntil) return false;
            Charge = 0; ActiveUntil = now + duration; return true;
        }
        public void Reset() { Charge = 0; ActiveUntil = 0; lastTick = double.NaN; wasEligible = false; }
        private void Add(float amount) => Charge = Math.Min(Maximum, Charge + amount);
        private static bool Finite(double n) => n >= 0 && !double.IsNaN(n) && !double.IsInfinity(n);
    }
}