Base85 Encoder and Decoder added

Author: rudimuc

Base85.ts

@@ -0,0 +1,66 @@
+import { Coder } from "./Coder";
+
+export class Base85Encoder implements Coder {
+
+    from = "text";
+    to = "base85";
+
+    transform(text: string): string {
+        const encoder = new TextEncoder();
+        const bytes = encoder.encode(text);
+        let base85 = "";
+
+        for (let i = 0; i < bytes.length; i += 4) {
+            let chunk = 0;
+            for (let j = 0; j < 4; j++) {
+                chunk = (chunk << 8) | (bytes[i + j] || 0);
+            }
+            for (let j = 4; j >= 0; j--) {
+                base85 += String.fromCharCode((chunk / (85 ** j) % 85) + 33);
+            }
+        }
+        return base85;
+    }
+
+    checkInput(text: string): boolean {
+        // Ensure the input is a non-empty string
+        return typeof text === "string" && text.length > 0;
+    }
+}
+
+export class Base85Decoder implements Coder {
+
+    from = "base85";
+    to = "text";
+
+    transform(text: string): string {
+        if (!this.checkInput(text)) {
+            throw new Error("Invalid Base85 input");
+        }
+
+        const decoder = new TextDecoder();
+        const chunks = text.match(/.{1,5}/g) || [];
+        const bytes = [];
+
+        for (const chunk of chunks) {
+            let value = 0;
+            for (let i = 0; i < chunk.length; i++) {
+                value = value * 85 + (chunk.charCodeAt(i) - 33);
+            }
+
+            for (let i = 3; i >= 0; i--) {
+                bytes.push((value >> (i * 8)) & 0xff);
+            }
+        }
+
+        return decoder.decode(new Uint8Array(bytes).filter(byte => byte !== 0));
+    }
+
+    checkInput(text: string): boolean {
+        // Check if the input is a valid Base64 string
+//        const base64Regex = /^[A-Za-z0-9+/=]+$/;
+//        return typeof text === "string" && base64Regex.test(text) && text.length % 4 === 0;
+        return true;
+    }
+
+}

main.ts

@@ -2,13 +2,23 @@ import { App, MarkdownView, Plugin, MarkdownPostProcessorContext, PluginSettingT
 
 import { Coder } from "./Coder";
 import { Base64Encoder, Base64Decoder } from "./Base64";
+import { Base85Encoder, Base85Decoder } from "./Base85";
 import { Rot13Encoder, Rot13Decoder } from "./Rot13";
 import { AtbashEncoder, AtbashDecoder } from "./Atbash";
 
 export default class CoderPlugin extends Plugin {
 
 	// List of coders
-	coders: Coder[] = [new Base64Encoder(), new Base64Decoder(), new Rot13Encoder(), new Rot13Decoder(), new AtbashEncoder(), new AtbashDecoder()];
+	coders: Coder[] = [
+		new Base64Encoder(),
+		new Base64Decoder(),
+		new Base85Encoder(),
+		new Base85Decoder(),
+		new Rot13Encoder(),
+		new Rot13Decoder(),
+		new AtbashEncoder(),
+		new AtbashDecoder()
+	];
 
 	async onload() {
 		this.coders.forEach(coder => {