1 files changed, 88 insertions, 0 deletions
diff --git a/src/SMAPI.Web/Framework/LogParsing/LogMessageBuilder.cs b/src/SMAPI.Web/Framework/LogParsing/LogMessageBuilder.cs
new file mode 100644
index 00000000..371acfd3
--- /dev/null
+++ b/src/SMAPI.Web/Framework/LogParsing/LogMessageBuilder.cs
@@ -0,0 +1,88 @@
+using System;
+using System.Text;
+using StardewModdingAPI.Web.Framework.LogParsing.Models;
+
+namespace StardewModdingAPI.Web.Framework.LogParsing
+{
+    /// <summary>Handles constructing log message instances with minimal memory allocation.</summary>
+    internal class LogMessageBuilder
+    {
+        /*********
+        ** Fields
+        *********/
+        /// <summary>The local time when the next log was posted.</summary>
+        public string Time { get; set; }
+
+        /// <summary>The log level for the next log message.</summary>
+        public LogLevel Level { get; set; }
+
+        /// <summary>The mod name for the next log message.</summary>
+        public string Mod { get; set; }
+
+        /// <summary>The text for the next log message.</summary>
+        private readonly StringBuilder Text = new StringBuilder();
+
+
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>Whether the next log message has been started.</summary>
+        public bool Started { get; private set; }
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Start accumulating values for a new log message.</summary>
+        /// <param name="time">The local time when the log was posted.</param>
+        /// <param name="level">The log level.</param>
+        /// <param name="mod">The mod name.</param>
+        /// <param name="text">The initial log text.</param>
+        /// <exception cref="InvalidOperationException">A log message is already started; call <see cref="Clear"/> before starting a new message.</exception>
+        public void Start(string time, LogLevel level, string mod, string text)
+        {
+            if (this.Started)
+                throw new InvalidOperationException("Can't start new message, previous log message isn't done yet.");
+
+            this.Started = true;
+
+            this.Time = time;
+            this.Level = level;
+            this.Mod = mod;
+            this.Text.AppendLine(text);
+        }
+
+        /// <summary>Add a new line to the next log message being built.</summary>
+        /// <param name="text">The line to add.</param>
+        /// <exception cref="InvalidOperationException">A log message hasn't been started yet.</exception>
+        public void AddLine(string text)
+        {
+            if (!this.Started)
+                throw new InvalidOperationException("Can't add text, no log message started yet.");
+
+            this.Text.AppendLine(text);
+        }
+
+        /// <summary>Get a log message for the accumulated values.</summary>
+        public LogMessage Build()
+        {
+            if (!this.Started)
+                return null;
+
+            return new LogMessage
+            {
+                Time = this.Time,
+                Level = this.Level,
+                Mod = this.Mod,
+                Text = this.Text.ToString()
+            };
+        }
+
+        /// <summary>Reset to start a new log message.</summary>
+        public void Clear()
+        {
+            this.Started = false;
+            this.Text.Clear();
+        }
+    }
+}