using System;
using System.Collections.Generic;

namespace DesertPaintLab
{
    public class PaintRecipe
    {
        public struct RGB
        {
            public int r;
            public int g;
            public int b;
        };

        private List<string> reagents = new List<string>();

        public PaintRecipe()
        {
        }

        public void AddReagent(String reagentName)
        {
            reagents.Add(reagentName);
        }

        public void Clear()
        {
            reagents.Clear();
        }

        byte CalculateColor(int baseSum, int pigmentCount, int reactSum)
        {
            return (byte)Math.Max(Math.Min(Math.Round((((float)baseSum / (float)pigmentCount) + (float)reactSum)), 255), 0);
        }

        // Compute the color including reactions based on the player's profile
        public void ComputeReactedColor(PlayerProfile profile, ref PaintColor paintColor)
        {
            RGB baseColor;
            baseColor.r = 0;
            baseColor.g = 0;
            baseColor.b = 0;
            RGB reactionColor;
            reactionColor.r = 0;
            reactionColor.g = 0;
            reactionColor.b = 0;

            int pigmentCount = 0;
            string prevReagent = null;

            // track visited reagents so the reaction is only applied once
            SortedDictionary<string,bool> reagentSet = new SortedDictionary<string,bool>();
            List<Reagent> prevReagents = new List<Reagent>();

            foreach (string reagentName in reagents)
            {
                if (reagentName == null)
                {
                    continue;   
                }
                
                Reagent reagent = ReagentManager.GetReagent(reagentName);
                if (!reagent.IsCatalyst)
                {
                    baseColor.r += reagent.Color.Red;
                    baseColor.g += reagent.Color.Green;
                    baseColor.b += reagent.Color.Blue;
                    pigmentCount += 1;
                }
                if (prevReagent == null || !prevReagent.Equals(reagentName))
                {
                    if (!reagentSet.ContainsKey(reagentName) && reagentSet.Count <= 4)
                    {
                        reagentSet[reagentName] = true;
                        // Run reactions.
                        foreach (Reagent otherReagent in prevReagents)
                        {
                            Reaction reaction = profile.FindReaction(otherReagent, reagent);
                            if (reaction != null)
                            {
                                reactionColor.r += reaction.Red;
                                reactionColor.g += reaction.Green;
                                reactionColor.b += reaction.Blue;
                            }
                        }
                        prevReagents.Add(reagent);
                    }
                }
                prevReagent = reagentName;
            }
            paintColor.Red = CalculateColor(baseColor.r, pigmentCount, reactionColor.r);
            paintColor.Green = CalculateColor(baseColor.g, pigmentCount, reactionColor.g);
            paintColor.Blue = CalculateColor(baseColor.b, pigmentCount, reactionColor.b);
        }

        // Compute the base color without any reactions
        public void ComputeBaseColor(ref PaintColor color)
        {
            RGB baseColor;
            baseColor.r = 0;
            baseColor.g = 0;
            baseColor.b = 0;
            int pigmentCount = 0;
            foreach (string reagentName in reagents)
            {
                if (reagentName == null)
                {
                    continue;   
                }
                
                Reagent reagent = ReagentManager.GetReagent(reagentName);
                if (!reagent.IsCatalyst)
                {
                    baseColor.r += reagent.Color.Red;
                    baseColor.g += reagent.Color.Green;
                    baseColor.b += reagent.Color.Blue;
                    pigmentCount += 1;
                }
            }
            color.Red = CalculateColor(baseColor.r, pigmentCount, 0);
            color.Green = CalculateColor(baseColor.g, pigmentCount, 0);
            color.Blue = CalculateColor(baseColor.b, pigmentCount, 0);
        }
    }
}