Add Decrypt to all relevant pages

src/main/resources/static/js/DecryptFiles.js

@@ -0,0 +1,116 @@
+export class DecryptFile {
+  async decryptFile(file, requiresPassword) {
+    try {
+      const formData = new FormData();
+      formData.append('fileInput', file);
+      if (requiresPassword) {
+        const password = prompt(`${window.decrypt.passwordPrompt}`);
+
+        if (password === null) {
+          // User cancelled
+          console.error(`Password prompt cancelled for PDF: ${file.name}`);
+          return null; // No file to return
+        }
+
+        if (!password) {
+          // No password provided
+          console.error(`No password provided for encrypted PDF: ${file.name}`);
+          this.showErrorBanner(
+            `${window.decrypt.noPassword.replace('{0}', file.name)}`,
+            '',
+            `${window.decrypt.unexpectedError}`
+          );
+          return null; // No file to return
+        }
+
+        formData.append('password', password);
+      }
+      // Send decryption request
+      const response = await fetch('/api/v1/security/remove-password', {
+        method: 'POST',
+        body: formData,
+      });
+
+      if (response.ok) {
+        const decryptedBlob = await response.blob();
+        this.removeErrorBanner();
+        return new File([decryptedBlob], file.name, {type: 'application/pdf'});
+      } else {
+        const errorText = await response.text();
+        console.error(`${window.decrypt.invalidPassword} ${errorText}`);
+        this.showErrorBanner(
+          `${window.decrypt.invalidPassword}`,
+          errorText,
+          `${window.decrypt.invalidPasswordHeader.replace('{0}', file.name)}`
+        );
+        return null; // No file to return
+      }
+    } catch (error) {
+      // Handle network or unexpected errors
+      console.error(`Failed to decrypt PDF: ${file.name}`, error);
+      this.showErrorBanner(
+        `${window.decrypt.unexpectedError.replace('{0}', file.name)}`,
+        `${error.message || window.decrypt.unexpectedError}`,
+        error
+      );
+      return null; // No file to return
+    }
+  }
+
+  async checkFileEncrypted(file) {
+    try {
+      if (file.type !== 'application/pdf') {
+        return {isEncrypted: false, requiresPassword: false};
+      }
+
+      pdfjsLib.GlobalWorkerOptions.workerSrc = './pdfjs-legacy/pdf.worker.mjs';
+      const arrayBuffer = await file.arrayBuffer();
+      const arrayBufferForPdfLib = arrayBuffer.slice(0);
+
+      const loadingTask = pdfjsLib.getDocument({
+        data: arrayBuffer,
+      });
+
+      await loadingTask.promise;
+
+      try {
+        //Uses PDFLib.PDFDocument to check if unpassworded but encrypted
+        const pdfDoc = await PDFLib.PDFDocument.load(arrayBufferForPdfLib);
+        return {isEncrypted: false, requiresPassword: false};
+      } catch (error) {
+        if (error.message.includes('Input document to `PDFDocument.load` is encrypted')) {
+          return {isEncrypted: true, requiresPassword: false};
+        }
+        console.error('Error checking encryption:', error);
+        throw new Error('Failed to determine if the file is encrypted.');
+      }
+    } catch (error) {
+      if (error.name === 'PasswordException') {
+        if (error.code === pdfjsLib.PasswordResponses.NEED_PASSWORD) {
+          return {isEncrypted: true, requiresPassword: true};
+        } else if (error.code === pdfjsLib.PasswordResponses.INCORRECT_PASSWORD) {
+          return {isEncrypted: true, requiresPassword: false};
+        }
+      }
+
+      console.error('Error checking encryption:', error);
+      throw new Error('Failed to determine if the file is encrypted.');
+    }
+  }
+
+  showErrorBanner(message, stackTrace, error) {
+    const errorContainer = document.getElementById('errorContainer');
+    errorContainer.style.display = 'block'; // Display the banner
+    errorContainer.querySelector('.alert-heading').textContent = error;
+    errorContainer.querySelector('p').textContent = message;
+    document.querySelector('#traceContent').textContent = stackTrace;
+  }
+
+  removeErrorBanner() {
+    const errorContainer = document.getElementById('errorContainer');
+    errorContainer.style.display = 'none'; // Hide the banner
+    errorContainer.querySelector('.alert-heading').textContent = '';
+    errorContainer.querySelector('p').textContent = '';
+    document.querySelector('#traceContent').textContent = '';
+  }
+}