From 83b2a11c80c7f8390bf2a5cdd0bab5474a5e991c Mon Sep 17 00:00:00 2001
From: "Tristan B. Velloza Kildaire" <deavmi@redxen.eu>
Date: Mon, 27 Mar 2023 15:40:20 +0200
Subject: [PATCH] Encoding

- Added stub class `TaggedMessage`
- Added constructor, static decoder (unimplemented), `encoder (implemented), getters and setters
- Added module `tristanable.encoding`
---
 source/tristanable/encoding.d | 109 ++++++++++++++++++++++++++++++++++
 1 file changed, 109 insertions(+)
 create mode 100644 source/tristanable/encoding.d

diff --git a/source/tristanable/encoding.d b/source/tristanable/encoding.d
new file mode 100644
index 0000000..4461068
--- /dev/null
+++ b/source/tristanable/encoding.d
@@ -0,0 +1,109 @@
+module tristanable.encoding;
+
+public final class TaggedMessage
+{
+    private ulong tag;
+    private byte[] data;
+
+    this(ulong tag, byte[] data)
+    {
+        this.tag = tag;
+        this.data = data;
+    }
+
+    /** 
+     * Decodes the wire-formatted tristanable bytes into an instance
+     * of TaggedMessage whereby the tag and data can be seperately
+     * accessed and manipulated
+     *
+     * Params:
+     *   encodedMessage = the wire-format encoded bytes
+     * Returns: an instance of TaggedMessage
+     */
+    public static TaggedMessage decode(byte[] encodedMessage)
+    {
+        /* The decoded message */
+        TaggedMessage decodedMessage;
+
+        /* Decoded tag */
+
+
+
+        // TODO: Implement me
+
+        return decodedMessage;
+    }
+
+    /** 
+     * Encodes the tagged message into the tristanable
+     * wire format ready for transmission
+     *
+     * Returns: the encoded bytes
+     */
+    public byte[] encode()
+    {
+        /* The encoded bytes */
+        byte[] encodedMessage;
+
+        /* If on little endian, then dump 64 bit as is - little endian */
+        version(LittleEndian)
+        {
+            /* Base (little first) of tag */
+            byte* basePtr = cast(byte*)&tag;
+
+            encodedMessage ~= *(basePtr+0);
+            encodedMessage ~= *(basePtr+1);
+            encodedMessage ~= *(basePtr+2);
+            encodedMessage ~= *(basePtr+3);
+            encodedMessage ~= *(basePtr+4);
+            encodedMessage ~= *(basePtr+5);
+            encodedMessage ~= *(basePtr+6);
+            encodedMessage ~= *(basePtr+7);
+        }
+        /* If on big endian, then traverse 64-bit number in reverse - and tack on */
+        else version(BigEndian)
+        {
+            /* Base (biggest first) of tag */
+            byte* highPtr = cast(byte*)&tag;
+
+            encodedMessage ~= *(highPtr+7);
+            encodedMessage ~= *(highPtr+6);
+            encodedMessage ~= *(highPtr+5);
+            encodedMessage ~= *(highPtr+4);
+            encodedMessage ~= *(highPtr+3);
+            encodedMessage ~= *(highPtr+2);
+            encodedMessage ~= *(highPtr+1);
+            encodedMessage ~= *(highPtr+0);
+        }
+        /* Hail marry, mother of God, pray for our sinners, now and at the our of our death Amen */
+        else
+        {
+            pragma(msg, "Not feeling scrumptious homeslice 😎️");
+        }
+
+        /* Tack on the data */
+        encodedMessage ~= data;
+
+        return encodedMessage;
+    }
+
+    public byte[] getPayload()
+    {
+        return data;
+    }
+
+    public ulong getTag()
+    {
+        return tag;
+    }
+
+    public void setPayload(byte[] newPayload)
+    {
+        this.data = newPayload;
+    }
+
+    public void setTag(ulong newTag)
+    {
+        this.tag = newTag;
+    }
+}
\ No newline at end of file