added bulk upload to guest book

app/api/guestbook/bulk-upload/route.ts

@@ -0,0 +1,81 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { prisma } from '@/lib/prisma'
+import { parse } from 'csv-parse/sync'
+
+export async function POST(req: NextRequest) {
+    try {
+        const formData = await req.formData()
+        const file = formData.get('file') as File
+
+        if (!file || file.type !== 'text/csv') {
+            return NextResponse.json({ message: "Invalid file type or missing CSV file."}, { status: 400 })
+        }
+
+        const buffer = Buffer.from(await file.arrayBuffer())
+        const csvString = buffer.toString('utf-8')
+
+        const records = parse(csvString, {
+            columns: true,
+            skip_empty_lines: true,
+            trim: true,
+        })
+
+        const validRecords = records.filter((r: any) => r.first && r.last && r.side)
+
+        let created = 0
+        let updated = 0
+
+        for (const r of validRecords) {
+            const existing = await prisma.guestBookEntry.findFirst({
+                where: {
+                    fName: r.first,
+                    lName: r.last,
+                }
+            })
+
+            const baseData = {
+                fName: r.first,
+                lName: r.last,
+                side: r.side,
+                email: r.email || undefined,
+                phone: r.phone || undefined,
+                address: r.address || undefined,
+                notes: r.notes || undefined,
+            }
+
+            if (existing) {
+                const updates: Record<string, string | undefined> = {}
+
+                if (!existing.email && r.email) updates.email = r.email
+                if (!existing.phone && r.phone) updates.phone = r.phone
+                if (!existing.address && r.address) updates.address = r.address
+                if (!existing.notes && r.notes) updates.notes = r.notes
+                if (!existing.side && r.side) updates.side = r.side
+
+                if (Object.keys(updates).length > 0) {
+                    await prisma.guestBookEntry.update({
+                        where: { id: existing.id },
+                        data: updates,
+                    })
+                    updated++
+                }
+            } else {
+                await prisma.guestBookEntry.create({
+                    data: baseData,
+                })
+                created++
+            }
+        }
+
+        return NextResponse.json({
+            success: true,
+            created,
+            updated,
+            totalProcessed: created + updated
+        })
+
+    } catch (err) {
+        console.error('[CSV Upload Error]', err)
+        return NextResponse.json({ message: 'Failed to upload guests' }, { status: 500 })
+    }
+}