created OperatorConstraints and impelemented it in impose

shared-operations/src/functions/impose.ts

@@ -1,13 +1,20 @@
 import { PdfFile, RepresentationType } from "../wrappers/PdfFile";
+import { FieldConstraint, RecordConstraint } from '../dynamic-ui/OperatorConstraints'
 
 export type ImposeParamsType = {
     file: PdfFile;
     /** Accepted values are 2, 3, 4, 8, 9, 12, 16 - see: {@link https://pdfcpu.io/generate/nup.html#n-up-value} */
-    nup: number;
+    nup: 2 | 3 | 4 | 8 | 9 | 12 | 16;
     /** A0-A10, other formats available - see: {@link https://pdfcpu.io/paper.html} */
     format: string;
 }
 
+export const ImposeParamConstraints = new RecordConstraint({
+    file: new FieldConstraint("display", "file.pdf", true, "hint"),
+    nup: new FieldConstraint("display", [2, 3, 4, 8, 9, 12, 16], true, "hint"),
+    format: new FieldConstraint("display", "string", true, "hint"),
+})
+
 /** PDF-Imposition, PDF-N-Up: Put multiple pages of the input document into a single page of the output document. - see: {@link https://en.wikipedia.org/wiki/N-up}  */
 export async function impose(params: ImposeParamsType, pdfcpuWrapper: any): Promise<PdfFile> {
     // https://pdfcpu.io/generate/nup.html
@@ -34,4 +41,4 @@ export async function impose(params: ImposeParamsType, pdfcpuWrapper: any): Prom
     
     console.log("ImposeResult: ", result);
     return result;
-}
+}