Continue Upload Script.

Pause during rewrite of RHPZ Server code.

ts/submissions/class-server-api.ts

@@ -0,0 +1,50 @@
+import { __, I } from "./globals";
+
+export class Server_Api {
+
+    url: string|undefined;
+    id: number|undefined;
+
+    init( server_url: string, server_id: number ){
+        this.url = server_url;
+        this.id = server_id;
+    }
+
+    is_init(): boolean {
+        return this.url !== undefined && this.id !== undefined;
+    }
+
+    private build_url( call: string ): string {
+
+        let new_url: string = this.url + "upload.php";
+        if( call === "check_existence" )
+            new_url += "?checkExistence=true";
+
+        return new_url;
+    }
+
+    async check_file_existence( filename: string ): Promise<boolean> {
+
+        return new Promise( ( resolve, reject ) => {
+
+            const XHR: XMLHttpRequest = new XMLHttpRequest();
+            XHR.open( 'POST', this.build_url( 'check_existence' ), true );
+
+            let form_data: FormData = new FormData();
+            form_data.append( "filename", filename );
+            form_data.append( 'reservedPostID', I.reserved_post_id );
+            form_data.append( 'custom_post_type', I.custom_post_type );
+
+            XHR.onload = () => {
+                resolve( XHR.responseText === 'exists' );
+            }
+            XHR.onerror = () => {
+                reject( false );
+            }
+
+            XHR.send( form_data );
+
+        });
+
+    }
+}