redirect the game's debug messages into trace logs (#233)

The game writes debug messages directly to the console, which shows up for SMAPI users. This commit redirects direct console messages to a monitor.

1 files changed, 79 insertions, 0 deletions

diff --git a/src/StardewModdingAPI/Framework/Logging/InterceptingTextWriter.cs b/src/StardewModdingAPI/Framework/Logging/InterceptingTextWriter.cs
new file mode 100644
index 00000000..14789109
--- /dev/null
+++ b/src/StardewModdingAPI/Framework/Logging/InterceptingTextWriter.cs
@@ -0,0 +1,79 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Text;
+
+namespace StardewModdingAPI.Framework.Logging
+{
+    /// <summary>A text writer which allows intercepting output.</summary>
+    internal class InterceptingTextWriter : TextWriter
+    {
+        /*********
+        ** Properties
+        *********/
+        /// <summary>The current line being intercepted.</summary>
+        private readonly List<char> Line = new List<char>();
+
+
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>The underlying console output.</summary>
+        public TextWriter Out { get; }
+
+        /// <summary>The character encoding in which the output is written.</summary>
+        public override Encoding Encoding => this.Out.Encoding;
+
+        /// <summary>Whether to intercept console output.</summary>
+        public bool ShouldIntercept { get; set; }
+
+        /// <summary>The event raised when a line of text is intercepted.</summary>
+        public event Action<string> OnLineIntercepted;
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="output">The underlying output writer.</param>
+        public InterceptingTextWriter(TextWriter output)
+        {
+            this.Out = output;
+        }
+
+        /// <summary>Writes a character to the text string or stream.</summary>
+        /// <param name="ch">The character to write to the text stream.</param>
+        public override void Write(char ch)
+        {
+            // intercept
+            if (this.ShouldIntercept)
+            {
+                switch (ch)
+                {
+                    case '\r':
+                        return;
+
+                    case '\n':
+                        this.OnLineIntercepted?.Invoke(new string(this.Line.ToArray()));
+                        this.Line.Clear();
+                        break;
+
+                    default:
+                        this.Line.Add(ch);
+                        break;
+                }
+            }
+
+            // pass through
+            else
+                this.Out.Write(ch);
+        }
+
+        /// <summary>Releases the unmanaged resources used by the <see cref="T:System.IO.TextWriter" /> and optionally releases the managed resources.</summary>
+        /// <param name="disposing">true to release both managed and unmanaged resources; false to release only unmanaged resources.</param>
+        protected override void Dispose(bool disposing)
+        {
+            this.OnLineIntercepted = null;
+        }
+    }
+}