added media class and packer to handle it

ts/media/index.ts

@@ -0,0 +1,40 @@
+import * as fs from "fs";
+import * as path from "path";
+
+interface IData {
+    referenceId: number;
+    stream: fs.ReadStream;
+    path: string;
+    fileName: string;
+}
+
+export class Media {
+    private map: Map<string, IData>;
+
+    constructor() {
+        this.map = new Map<string, IData>();
+    }
+
+    public getMedia(key: string): IData | undefined {
+        return this.map.get(key);
+    }
+
+    public addMedia(key: string, filePath: string): void {
+        this.map.set(key, {
+            referenceId: this.map.values.length,
+            stream: fs.createReadStream(filePath),
+            path: filePath,
+            fileName: path.basename(filePath),
+        });
+    }
+
+    public get array(): IData[] {
+        const array = new Array<IData>();
+
+        this.map.forEach((data) => {
+            array.push(data);
+        });
+
+        return array;
+    }
+}