feat: Equipment-System, Buchungsbearbeitung, Kundenadresse, LexOffice-Fix

- Vintage Modell hinzugefuegt
- Equipment Multi-Select (Neue Buchung + Bearbeitung)
- Kundenadresse in Formularen
- Bearbeiten-Seite fuer Buchungen
- Abbau-Zeiten in Formularen und Uebersicht
- Vertrag PDF nur bei Privatkunden
- LexOffice Kontakt-Erstellung Fix (BUSINESS)
- Zurueck-Pfeil auf Touren-Seite

lib/price-calculator.ts

@@ -0,0 +1,108 @@
+interface PriceConfig {
+  basePrice: number;
+  kmFlatRate: number;
+  kmFlatRateUpTo: number;
+  pricePerKm: number;
+  kmMultiplier: number;
+}
+
+interface PriceBreakdown {
+  basePrice: number;
+  kmFlatRate: number;
+  kmAdditionalNet: number;
+  kmAdditionalGross: number;
+  kmTotalGross: number;
+  totalPrice: number;
+  distance?: number;
+}
+
+export class PriceCalculator {
+  private static readonly VAT_RATE = 1.19;
+
+  static calculateKmCharge(
+    distance: number,
+    config: PriceConfig
+  ): {
+    kmTotalGross: number;
+    kmFlatRate: number;
+    kmAdditionalNet: number;
+    kmAdditionalGross: number;
+  } {
+    const { kmFlatRate, kmFlatRateUpTo, pricePerKm, kmMultiplier } = config;
+
+    if (distance <= kmFlatRateUpTo) {
+      return {
+        kmTotalGross: kmFlatRate,
+        kmFlatRate: kmFlatRate,
+        kmAdditionalNet: 0,
+        kmAdditionalGross: 0,
+      };
+    }
+
+    const extraKm = distance - kmFlatRateUpTo;
+    const kmAdditionalNet = extraKm * kmMultiplier * pricePerKm;
+    const kmAdditionalGross = Math.round(kmAdditionalNet * this.VAT_RATE * 100) / 100;
+    const kmTotalGross = Math.round((kmFlatRate + kmAdditionalGross) * 100) / 100;
+
+    return {
+      kmTotalGross,
+      kmFlatRate,
+      kmAdditionalNet: Math.round(kmAdditionalNet * 100) / 100,
+      kmAdditionalGross,
+    };
+  }
+
+  static calculateTotalPrice(
+    basePrice: number,
+    distance: number | null | undefined,
+    config: PriceConfig
+  ): PriceBreakdown {
+    if (!distance || distance <= 0) {
+      return {
+        basePrice,
+        kmFlatRate: 0,
+        kmAdditionalNet: 0,
+        kmAdditionalGross: 0,
+        kmTotalGross: 0,
+        totalPrice: basePrice,
+      };
+    }
+
+    const kmCharge = this.calculateKmCharge(distance, config);
+    const totalPrice = Math.round((basePrice + kmCharge.kmTotalGross) * 100) / 100;
+
+    return {
+      basePrice,
+      kmFlatRate: kmCharge.kmFlatRate,
+      kmAdditionalNet: kmCharge.kmAdditionalNet,
+      kmAdditionalGross: kmCharge.kmAdditionalGross,
+      kmTotalGross: kmCharge.kmTotalGross,
+      totalPrice,
+      distance,
+    };
+  }
+
+  static formatPriceBreakdown(breakdown: PriceBreakdown): string {
+    const lines = [
+      `Grundpreis Fotobox: ${breakdown.basePrice.toFixed(2)}€`,
+    ];
+
+    if (breakdown.distance && breakdown.distance > 0) {
+      lines.push(`\nKilometerpauschale (${breakdown.distance.toFixed(1)}km):`);
+      
+      if (breakdown.kmFlatRate > 0) {
+        lines.push(`  - Pauschale: ${breakdown.kmFlatRate.toFixed(2)}€`);
+      }
+      
+      if (breakdown.kmAdditionalGross > 0) {
+        lines.push(`  - Zusätzlich: ${breakdown.kmAdditionalGross.toFixed(2)}€`);
+      }
+      
+      lines.push(`  = Gesamt KM: ${breakdown.kmTotalGross.toFixed(2)}€`);
+    }
+
+    lines.push(`\nGesamtpreis: ${breakdown.totalPrice.toFixed(2)}€`);
+
+    return lines.join('\n');
+  }
+}