Urist's damage and health thing. (#10)

* Add prototype for temperature testing entity.

* Add Damageable, Destructible, Temperature. Add a prototype based on those.

* Works and cleaned up.

* Nerf

Content.Server/GameObjects/Components/Damage/ResistanceSet.cs

@@ -0,0 +1,115 @@
+using System;
+using System.Collections.Generic;
+
+namespace Content.Server.GameObjects
+{
+    /// <summary>
+    /// Damage types used in-game.
+    /// Total should never be used directly - it's a derived value.
+    /// </summary>
+    public enum DamageType
+    {
+        Total,
+        Brute,
+        Heat,
+        Cold,
+        Acid,
+        Toxic,
+        Electric
+    }
+
+    /// <summary>
+    /// Resistance set used by damageable objects.
+    /// For each damage type, has a coefficient, damage reduction and "included in total" value.
+    /// </summary>
+    public class ResistanceSet
+    {
+        Dictionary<DamageType, ResistanceSetSettings> _resistances = new Dictionary<DamageType, ResistanceSetSettings>();
+        static Dictionary<string, ResistanceSet> _resistanceSets = new Dictionary<string, ResistanceSet>();
+
+        //TODO: make it load from YAML instead of hardcoded like this
+        public ResistanceSet()
+        {
+            _resistances.Add(DamageType.Total, new ResistanceSetSettings(1f, 0, true));
+            _resistances.Add(DamageType.Acid, new ResistanceSetSettings(1f, 0, true));
+            _resistances.Add(DamageType.Brute, new ResistanceSetSettings(1f, 0, true));
+            _resistances.Add(DamageType.Heat, new ResistanceSetSettings(1f, 0, true));
+            _resistances.Add(DamageType.Cold, new ResistanceSetSettings(1f, 0, true));
+            _resistances.Add(DamageType.Toxic, new ResistanceSetSettings(1f, 0, true));
+            _resistances.Add(DamageType.Electric, new ResistanceSetSettings(1f, 0, true));
+        }
+
+        /// <summary>
+        /// Loads a resistance set with the given name.
+        /// </summary>
+        /// <param name="setName">Name of the resistance set.</param>
+        /// <returns>Resistance set by given name</returns>
+        public static ResistanceSet GetResistanceSet(string setName)
+        {
+            ResistanceSet resistanceSet = null;
+
+            if (!_resistanceSets.TryGetValue(setName, out resistanceSet))
+            {
+                resistanceSet = Load(setName);
+            }
+
+            return resistanceSet;
+        }
+
+        static ResistanceSet Load(string setName)
+        {
+            //TODO: only creates a standard set RN, should be YAMLed
+
+            ResistanceSet resistanceSet = new ResistanceSet();
+
+            _resistanceSets.Add(setName, resistanceSet);
+
+            return resistanceSet;
+        }
+
+        /// <summary>
+        /// Adjusts input damage with the resistance set values.
+        /// </summary>
+        /// <param name="damageType">Type of the damage.</param>
+        /// <param name="amount">Incoming amount of the damage.</param>
+        /// <returns>Damage adjusted by the resistance set.</returns>
+        public int CalculateDamage(DamageType damageType, int amount)
+        {
+            if (amount > 0) //if it's damage, reduction applies
+            {
+                amount -= _resistances[damageType].DamageReduction;
+
+                if (amount <= 0)
+                    return 0;
+            }
+
+            amount = (int)Math.Floor(amount * _resistances[damageType].Coefficient);
+
+            return amount;
+        }
+
+        public bool AppliesToTotal(DamageType damageType)
+        {
+            //Damage that goes straight to total (for whatever reason) never applies twice
+
+            return damageType == DamageType.Total ? false : _resistances[damageType].AppliesToTotal;
+        }
+
+        /// <summary>
+        /// Settings for a specific damage type in a resistance set.
+        /// </summary>
+        struct ResistanceSetSettings
+        {
+            public float Coefficient { get; private set; }
+            public int DamageReduction { get; private set; }
+            public bool AppliesToTotal { get; private set; }
+
+            public ResistanceSetSettings(float coefficient, int damageReduction, bool appliesInTotal)
+            {
+                Coefficient = coefficient;
+                DamageReduction = damageReduction;
+                AppliesToTotal = appliesInTotal;
+            }
+        }
+    }
+}