Job Gauge update

Dalamud/Game/ClientState/JobGauge/JobGauges.cs

@@ -0,0 +1,50 @@
+using System;
+using System.Collections.Generic;
+using System.Reflection;
+
+using Dalamud.Game.ClientState.JobGauge.Types;
+using Serilog;
+
+namespace Dalamud.Game.ClientState.JobGauge
+{
+    /// <summary>
+    /// This class converts in-memory Job gauge data to structs.
+    /// </summary>
+    public class JobGauges
+    {
+        private Dictionary<Type, JobGaugeBase> cache = new();
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="JobGauges"/> class.
+        /// </summary>
+        /// <param name="addressResolver">Address resolver with the JobGauge memory location(s).</param>
+        public JobGauges(ClientStateAddressResolver addressResolver)
+        {
+            this.Address = addressResolver.JobGaugeData;
+
+            Log.Verbose($"JobGaugeData address 0x{this.Address.ToInt64():X}");
+        }
+
+        /// <summary>
+        /// Gets the address of the JobGauge data.
+        /// </summary>
+        public IntPtr Address { get; }
+
+        /// <summary>
+        /// Get the JobGauge for a given job.
+        /// </summary>
+        /// <typeparam name="T">A JobGauge struct from ClientState.Structs.JobGauge.</typeparam>
+        /// <returns>A JobGauge.</returns>
+        public T Get<T>() where T : JobGaugeBase
+        {
+            // This is cached to mitigate the effects of using activator for instantiation.
+            // Since the gauge itself reads from live memory, there isn't much downside to doing this.
+            if (!this.cache.TryGetValue(typeof(T), out var gauge))
+            {
+                gauge = this.cache[typeof(T)] = (T)Activator.CreateInstance(typeof(T), BindingFlags.NonPublic | BindingFlags.Instance, null, new object[] { this.Address }, null);
+            }
+
+            return (T)gauge;
+        }
+    }
+}