allow user to cancel pdf password prompt

fixes #120

src/lib/pdf.ts

@@ -57,9 +57,14 @@ function makeRow(cells: TextItemWithPosition[]): string[] {
  * @param data
  */
 export async function pdf2array(data: ArrayBuffer): Promise<string[][]> {
-  const loader = await pdfjs.getDocument(data);
+  const loader = pdfjs.getDocument(data);
   loader.onPassword = (cb: any) => {
-    const password = prompt("Please enter the password to open this PDF file.");
+    const password = prompt(
+      "Please enter the password to open this PDF file. Press cancel to exit."
+    );
+    if (!password) {
+      throw new Error("Password required.");
+    }
     cb(password);
   };
   const doc = await loader.promise;

src/lib/sheet.ts

@@ -6,6 +6,7 @@ import { pdf2array } from "./pdf";
 
 interface Result {
   data: string[][];
+  error?: string;
 }
 
 export function parse(file: File): Promise<Result> {
@@ -84,9 +85,13 @@ async function parseXLSX(file: File): Promise<Result> {
 }
 
 async function parsePDF(file: File): Promise<Result> {
-  const buffer = await readFile(file);
-  const array = await pdf2array(buffer);
-  return { data: array };
+  try {
+    const buffer = await readFile(file);
+    const array = await pdf2array(buffer);
+    return { data: array };
+  } catch (e) {
+    return { data: [], error: e.message };
+  }
 }
 
 function readFile(file: File): Promise<ArrayBuffer> {

src/routes/(app)/ledger/import/+page.svelte

@@ -24,6 +24,7 @@
   let lastTemplate: any;
   let lastData: any;
   let preview = "";
+  let parseErrorMessage: string = null;
   let columnCount: number;
   let data: any[][] = [];
   let rows: Array<Record<string, any>> = [];
@@ -114,13 +115,18 @@
     const { acceptedFiles } = e.detail;
 
     const results = await parse(acceptedFiles[0]);
-    data = results.data;
-    rows = asRows(results);
+    if (results.error) {
+      parseErrorMessage = results.error;
+    } else {
+      parseErrorMessage = null;
+      data = results.data;
+      rows = asRows(results);
 
-    columnCount = _.maxBy(data, (row) => row.length).length;
-    _.each(data, (row) => {
-      row.length = columnCount;
-    });
+      columnCount = _.maxBy(data, (row) => row.length).length;
+      _.each(data, (row) => {
+        row.length = columnCount;
+      });
+    }
   }
 
   async function copyToClipboard() {
@@ -303,6 +309,12 @@
             <label for="import-reverse">Reverse</label>
           </div>
         </div>
+        {#if parseErrorMessage}
+          <div class="message invertable is-danger">
+            <div class="message-header">Failed to parse document</div>
+            <div class="message-body">{parseErrorMessage}</div>
+          </div>
+        {/if}
         {#if !_.isEmpty(data)}
           <div class="table-wrapper">
             <table