backend/src/main/java/com/printcalculator/controller/OrderController.java

@@ -212,15 +212,16 @@ public class OrderController {
 
     @GetMapping("/{orderId}/twint")
     public ResponseEntity<Map<String, String>> getTwintPayment(@PathVariable UUID orderId) {
-        if (!orderRepo.existsById(orderId)) {
+        Order order = orderRepo.findById(orderId).orElse(null);
+        if (order == null) {
             return ResponseEntity.notFound().build();
         }
 
-        byte[] qrPng = twintPaymentService.generateQrPng(360);
+        byte[] qrPng = twintPaymentService.generateQrPng(order, 360);
         String qrDataUri = "data:image/png;base64," + Base64.getEncoder().encodeToString(qrPng);
 
         Map<String, String> data = new HashMap<>();
-        data.put("paymentUrl", twintPaymentService.getTwintPaymentUrl());
+        data.put("paymentUrl", twintPaymentService.getTwintPaymentUrl(order));
         data.put("openUrl", "/api/orders/" + orderId + "/twint/open");
         data.put("qrImageUrl", "/api/orders/" + orderId + "/twint/qr");
         data.put("qrImageDataUri", qrDataUri);
@@ -229,12 +230,13 @@ public class OrderController {
 
     @GetMapping("/{orderId}/twint/open")
     public ResponseEntity<Void> openTwintPayment(@PathVariable UUID orderId) {
-        if (!orderRepo.existsById(orderId)) {
+        Order order = orderRepo.findById(orderId).orElse(null);
+        if (order == null) {
             return ResponseEntity.notFound().build();
         }
 
         return ResponseEntity.status(302)
-                .location(URI.create(twintPaymentService.getTwintPaymentUrl()))
+                .location(URI.create(twintPaymentService.getTwintPaymentUrl(order)))
                 .build();
     }
 
@@ -243,12 +245,13 @@ public class OrderController {
             @PathVariable UUID orderId,
             @RequestParam(defaultValue = "320") int size
     ) {
-        if (!orderRepo.existsById(orderId)) {
+        Order order = orderRepo.findById(orderId).orElse(null);
+        if (order == null) {
             return ResponseEntity.notFound().build();
         }
 
         int normalizedSize = Math.max(200, Math.min(size, 600));
-        byte[] png = twintPaymentService.generateQrPng(normalizedSize);
+        byte[] png = twintPaymentService.generateQrPng(order, normalizedSize);
 
         return ResponseEntity.ok()
                 .contentType(MediaType.IMAGE_PNG)

backend/src/main/java/com/printcalculator/controller/QuoteSessionController.java

@@ -71,7 +71,7 @@ public class QuoteSessionController {
         session.setPricingVersion("v1");
         // Default material/settings will be set when items are added or updated?
         // For now set safe defaults
-        session.setMaterialCode("pla_basic"); 
+        session.setMaterialCode("PLA"); 
         session.setSupportsEnabled(false);
         session.setCreatedAt(OffsetDateTime.now());
         session.setExpiresAt(OffsetDateTime.now().plusDays(30)); 
@@ -125,6 +125,15 @@ public class QuoteSessionController {
             // Apply Basic/Advanced Logic
             applyPrintSettings(settings);
 
+            // Update session global settings from the most recent item added
+            session.setMaterialCode(settings.getMaterial());
+            session.setNozzleDiameterMm(BigDecimal.valueOf(settings.getNozzleDiameter() != null ? settings.getNozzleDiameter() : 0.4));
+            session.setLayerHeightMm(BigDecimal.valueOf(settings.getLayerHeight() != null ? settings.getLayerHeight() : 0.2));
+            session.setInfillPattern(settings.getInfillPattern());
+            session.setInfillPercent(settings.getInfillDensity() != null ? settings.getInfillDensity().intValue() : 20);
+            session.setSupportsEnabled(settings.getSupportsEnabled() != null ? settings.getSupportsEnabled() : false);
+            sessionRepo.save(session);
+
             // REAL SLICING
             // 1. Pick Machine (default to first active or specific)
             PrinterMachine machine = machineRepo.findFirstByIsActiveTrue()

backend/src/main/java/com/printcalculator/dto/PrintSettingsDto.java

@@ -15,6 +15,7 @@ public class PrintSettingsDto {
     private String quality;  // "draft", "standard", "high"
     
     // Advanced Mode (Optional in Basic)
+    private Double nozzleDiameter;
     private Double layerHeight;
     private Double infillDensity;
     private String infillPattern;

backend/src/main/java/com/printcalculator/service/TwintPaymentService.java

@@ -21,14 +21,37 @@ public class TwintPaymentService {
         this.twintPaymentUrl = twintPaymentUrl;
     }
 
-    public String getTwintPaymentUrl() {
+    public String getTwintPaymentUrl(com.printcalculator.entity.Order order) {
-        return twintPaymentUrl;
+        StringBuilder urlBuilder = new StringBuilder(twintPaymentUrl);
+        
+        if (order != null) {
+            if (order.getTotalChf() != null) {
+                urlBuilder.append("&amount=").append(order.getTotalChf().toPlainString());
+            }
+            
+            String orderNumber = order.getOrderNumber();
+            if (orderNumber == null && order.getId() != null) {
+                orderNumber = order.getId().toString();
+            }
+            
+            if (orderNumber != null) {
+                try {
+                    urlBuilder.append("&trxInfo=").append(order.getId());
+                } catch (Exception e) {
+                    e.printStackTrace();
+                    return null;
+                }
+            }
+        }
+        
+        return urlBuilder.toString();
     }
 
-    public byte[] generateQrPng(int sizePx) {
+    public byte[] generateQrPng(com.printcalculator.entity.Order order, int sizePx) {
         try {
+            String url = getTwintPaymentUrl(order);
             // Use High Error Correction for financial QR codes
-            QrCode qrCode = QrCode.encodeText(twintPaymentUrl, QrCode.Ecc.HIGH);
+            QrCode qrCode = QrCode.encodeText(url, QrCode.Ecc.HIGH);
             
             // Standard QR quiet zone is 4 modules
             int borderModules = 4;

backend/src/main/resources/application.properties

@@ -31,7 +31,7 @@ payment.twint.url=${TWINT_PAYMENT_URL:https://go.twint.ch/1/e/tw?tw=acq.gERQQytO
 spring.mail.host=${MAIL_HOST:mail.infomaniak.com}
 spring.mail.port=${MAIL_PORT:587}
 spring.mail.username=${MAIL_USERNAME:info@3d-fab.ch}
-spring.mail.password=${MAIL_PASSWORD:ht*44k+Tq39R+R-O}
+spring.mail.password=${MAIL_PASSWORD:}
 spring.mail.properties.mail.smtp.auth=${MAIL_SMTP_AUTH:false}
 spring.mail.properties.mail.smtp.starttls.enable=${MAIL_SMTP_STARTTLS:false}
 

frontend/src/app/features/calculator/calculator-page.component.ts

@@ -49,7 +49,11 @@ export class CalculatorPageComponent implements OnInit {
     this.route.queryParams.subscribe(params => {
         const sessionId = params['session'];
         if (sessionId) {
-            this.loadSession(sessionId);
+            // Avoid reloading if we just calculated this session
+            const currentRes = this.result();
+            if (!currentRes || currentRes.sessionId !== sessionId) {
+                this.loadSession(sessionId);
+            }
         }
     });
   }

frontend/src/app/features/calculator/services/quote-estimator.service.ts

@@ -215,7 +215,7 @@ export class QuoteEstimatorService {
                      
                      const settings = {
                          complexityMode: request.mode.toUpperCase(),
-                         material: this.mapMaterial(request.material),
+                         material: request.material,
                          quality: request.quality,
                          supportsEnabled: request.supportEnabled,
                          color: item.color || '#FFFFFF',
@@ -317,14 +317,6 @@ export class QuoteEstimatorService {
     });
   }
 
-  private mapMaterial(mat: string): string {
-    const m = mat.toUpperCase();
-    if (m.includes('PLA')) return 'pla_basic';
-    if (m.includes('PETG')) return 'petg_basic';
-    if (m.includes('TPU')) return 'tpu_95a';
-    return 'pla_basic';
-  }
-
   // Consultation Data Transfer
   private pendingConsultation = signal<{files: File[], message: string} | null>(null);
 

frontend/src/app/features/order/order.component.html

@@ -71,10 +71,17 @@
                 <img *ngIf="twintQrUrl()" class="twint-qr" [src]="getTwintQrUrl()" (error)="onTwintQrError()" alt="TWINT payment QR" />
                 <p>{{ 'PAYMENT.TWINT_DESC' | translate }}</p>
                 <p class="billing-hint">{{ 'PAYMENT.BILLING_INFO_HINT' | translate }}</p>
-                <div class="twint-mobile-action">
+                <div class="twint-mobile-action twint-button-container">
-                  <app-button (click)="openTwintPayment()" [fullWidth]="true">
+                  <button style="width: auto; height: 58px;
-                    {{ 'PAYMENT.TWINT_OPEN' | translate }}
+border-radius: 6px;
-                  </app-button>
+display: flex;
+justify-content: center;
+cursor: pointer;
+background-color: transparent;
+border: none;
+align-items: center;" (click)="openTwintPayment()">
+                    <img style="width: auto; height: 58px" alt="Embedded TWINT button" [src]="getTwintButtonImageUrl()"/>
+                  </button>
                 </div>
                 <p class="amount">{{ 'PAYMENT.TOTAL' | translate }}: {{ o.totalChf | currency:'CHF' }}</p>
               </div>

frontend/src/app/features/order/order.component.scss

@@ -150,6 +150,8 @@
     width: 100%;
     max-width: 320px;
     margin-top: var(--space-3);
+    display: flex;
+    justify-content: center;
   }
 
   .amount {

frontend/src/app/features/order/order.component.ts

@@ -4,7 +4,7 @@ import { ActivatedRoute, Router } from '@angular/router';
 import { AppButtonComponent } from '../../shared/components/app-button/app-button.component';
 import { AppCardComponent } from '../../shared/components/app-card/app-card.component';
 import { QuoteEstimatorService } from '../calculator/services/quote-estimator.service';
-import { TranslateModule } from '@ngx-translate/core';
+import { TranslateModule, TranslateService } from '@ngx-translate/core';
 import { environment } from '../../../environments/environment';
 
 @Component({
@@ -18,6 +18,7 @@ export class OrderComponent implements OnInit {
   private route = inject(ActivatedRoute);
   private router = inject(Router);
   private quoteService = inject(QuoteEstimatorService);
+  private translate = inject(TranslateService);
 
   orderId: string | null = null;
   selectedPaymentMethod: 'twint' | 'bill' | null = 'twint';
@@ -101,6 +102,15 @@ export class OrderComponent implements OnInit {
     return this.twintQrUrl() ?? '';
   }
 
+  getTwintButtonImageUrl(): string {
+    const lang = this.translate.currentLang;
+    if (lang === 'de') {
+      return 'https://go.twint.ch/static/img/button_dark_de.svg';
+    }
+    // Default to EN for everything else (it, fr, en) as instructed or if not DE
+    return 'https://go.twint.ch/static/img/button_dark_en.svg';
+  }
+
   onTwintQrError(): void {
     this.twintQrUrl.set(null);
   }

frontend/src/assets/i18n/it.json

@@ -262,7 +262,7 @@
     "BANK_OWNER": "Titolare",
     "BANK_IBAN": "IBAN",
     "BANK_REF": "Riferimento",
-    "BILLING_INFO_HINT": "Aggiungi le informazioni uguali a quelle della fatturazione.",
+    "BILLING_INFO_HINT": "Abbiamo compilato i campi per te, per favore non modificare il motivo del pagamento",
     "DOWNLOAD_QR": "Scarica QR-Fattura (PDF)",
     "CONFIRM": "Ho completato il pagamento",
     "SUMMARY_TITLE": "Riepilogo Ordine",