From ed87b428394f1f5a236b789a8af586133def323b Mon Sep 17 00:00:00 2001
From: Manuel Friedli <manuel@fritteli.ch>
Date: Fri, 31 Aug 2018 21:47:18 +0200
Subject: [PATCH] Add ROT-13 conversion

---
 src/app/converter/rot13converter.ts  | 25 +++++++++++++++++++++++++
 src/app/converterregistry.service.ts |  2 ++
 2 files changed, 27 insertions(+)
 create mode 100644 src/app/converter/rot13converter.ts

diff --git a/src/app/converter/rot13converter.ts b/src/app/converter/rot13converter.ts
new file mode 100644
index 0000000..ed51b5d
--- /dev/null
+++ b/src/app/converter/rot13converter.ts
@@ -0,0 +1,25 @@
+import {Converter} from './converter';
+
+export class ROT13Converter implements Converter {
+  getDisplayname(): string {
+    return 'Perform ROT-13';
+  }
+
+  getId(): string {
+    return 'rot13convert';
+  }
+
+  convert(input: string): string {
+    try {
+      const inChars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
+      const outChars = 'NOPQRSTUVWXYZABCDEFGHIJKLMnopqrstuvwxyzabcdefghijklm';
+      const translate = c => {
+        const charIndex = inChars.indexOf(c);
+        return charIndex > -1 ? outChars[charIndex] : c;
+      };
+      return input.split('').map(translate).join('');
+    } catch (exception) {
+      throw new Error('Could not perform ROT-13 conversion. Maybe corrupt input?');
+    }
+  }
+}
diff --git a/src/app/converterregistry.service.ts b/src/app/converterregistry.service.ts
index 4e4bf1a..4d66673 100644
--- a/src/app/converterregistry.service.ts
+++ b/src/app/converterregistry.service.ts
@@ -19,6 +19,7 @@ import {PunycodeEncoder} from './converter/punycodeencoder';
 import {PunycodeDecoder} from './converter/punycodedecoder';
 import {UTF8Encoder} from './converter/utf8encoder';
 import {UTF8Decoder} from './converter/utf8decoder';
+import {ROT13Converter} from './converter/rot13converter';
 
 @Injectable()
 export class ConverterRegistryService {
@@ -60,6 +61,7 @@ export class ConverterRegistryService {
     this.registerConverter(new PunycodeDecoder(this.wrapper));
     this.registerConverter(new UTF8Encoder(this.wrapper));
     this.registerConverter(new UTF8Decoder(this.wrapper));
+    this.registerConverter(new ROT13Converter());
   }
 
   private registerConverter(converter: Converter): void {