feat: implement email verification and unsubscribe DB logic

- Export EmailStatus enum from db-types.ts
- Add verifyTenantEmail server action
- Add unsubscribeTenantEmail server action
- Both actions update current and all subsequent matching locations
- Match criteria: userId, name, tenantEmail, yearMonth >= current
- Share-id validation using existing shareChecksum utilities

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

web-app/app/lib/actions/emailActions.ts

@@ -0,0 +1,175 @@
+'use server';
+
+import { getDbClient } from '../dbClient';
+import { BillingLocation, EmailStatus } from '../db-types';
+import { extractShareId, validateShareChecksum } from '../shareChecksum';
+import { revalidatePath } from 'next/cache';
+
+export type EmailActionResult = {
+    success: boolean;
+    message?: string;
+};
+
+/**
+ * Verify tenant email address
+ * Updates the email status to Verified for the location and all subsequent matching locations
+ *
+ * @param shareId - The share ID from the verification link (locationId + checksum)
+ * @returns Result indicating success or failure
+ */
+export async function verifyTenantEmail(shareId: string): Promise<EmailActionResult> {
+    // Extract and validate share ID
+    const extracted = extractShareId(shareId);
+    if (!extracted) {
+        return {
+            success: false,
+            message: 'Invalid verification link'
+        };
+    }
+
+    const { locationId, checksum } = extracted;
+
+    // Validate checksum
+    if (!validateShareChecksum(locationId, checksum)) {
+        return {
+            success: false,
+            message: 'Invalid verification link'
+        };
+    }
+
+    // Get database client
+    const dbClient = await getDbClient();
+
+    // Fetch the location to get userId, name, tenantEmail, and yearMonth
+    const location = await dbClient.collection<BillingLocation>("lokacije")
+        .findOne(
+            { _id: locationId },
+            { projection: { userId: 1, name: 1, tenantEmail: 1, yearMonth: 1 } }
+        );
+
+    if (!location) {
+        return {
+            success: false,
+            message: 'Location not found'
+        };
+    }
+
+    if (!location.tenantEmail) {
+        return {
+            success: false,
+            message: 'No tenant email configured for this location'
+        };
+    }
+
+    // Update current and all subsequent matching locations
+    // Match by: userId, name, tenantEmail, and yearMonth >= current
+    const result = await dbClient.collection<BillingLocation>("lokacije").updateMany(
+        {
+            userId: location.userId,
+            name: location.name,
+            tenantEmail: location.tenantEmail,
+            $or: [
+                { "yearMonth.year": { $gt: location.yearMonth.year } },
+                {
+                    "yearMonth.year": location.yearMonth.year,
+                    "yearMonth.month": { $gte: location.yearMonth.month }
+                }
+            ]
+        },
+        {
+            $set: {
+                tenantEmailStatus: EmailStatus.Verified
+            }
+        }
+    );
+
+    // Revalidate paths to refresh UI
+    revalidatePath('/[locale]', 'layout');
+
+    return {
+        success: true,
+        message: `Email verified successfully (${result.modifiedCount} location(s) updated)`
+    };
+}
+
+/**
+ * Unsubscribe tenant from email notifications
+ * Updates the email status to Unsubscribed for the location and all subsequent matching locations
+ *
+ * @param shareId - The share ID from the unsubscribe link (locationId + checksum)
+ * @returns Result indicating success or failure
+ */
+export async function unsubscribeTenantEmail(shareId: string): Promise<EmailActionResult> {
+    // Extract and validate share ID
+    const extracted = extractShareId(shareId);
+    if (!extracted) {
+        return {
+            success: false,
+            message: 'Invalid unsubscribe link'
+        };
+    }
+
+    const { locationId, checksum } = extracted;
+
+    // Validate checksum
+    if (!validateShareChecksum(locationId, checksum)) {
+        return {
+            success: false,
+            message: 'Invalid unsubscribe link'
+        };
+    }
+
+    // Get database client
+    const dbClient = await getDbClient();
+
+    // Fetch the location to get userId, name, tenantEmail, and yearMonth
+    const location = await dbClient.collection<BillingLocation>("lokacije")
+        .findOne(
+            { _id: locationId },
+            { projection: { userId: 1, name: 1, tenantEmail: 1, yearMonth: 1 } }
+        );
+
+    if (!location) {
+        return {
+            success: false,
+            message: 'Location not found'
+        };
+    }
+
+    if (!location.tenantEmail) {
+        return {
+            success: false,
+            message: 'No tenant email configured for this location'
+        };
+    }
+
+    // Update current and all subsequent matching locations
+    // Match by: userId, name, tenantEmail, and yearMonth >= current
+    const result = await dbClient.collection<BillingLocation>("lokacije").updateMany(
+        {
+            userId: location.userId,
+            name: location.name,
+            tenantEmail: location.tenantEmail,
+            $or: [
+                { "yearMonth.year": { $gt: location.yearMonth.year } },
+                {
+                    "yearMonth.year": location.yearMonth.year,
+                    "yearMonth.month": { $gte: location.yearMonth.month }
+                }
+            ]
+        },
+        {
+            $set: {
+                tenantEmailStatus: EmailStatus.Unsubscribed
+            }
+        }
+    );
+
+    // Revalidate paths to refresh UI
+    revalidatePath('/[locale]', 'layout');
+
+    return {
+        success: true,
+        message: `Unsubscribed successfully (${result.modifiedCount} location(s) updated)`
+    };
+}

web-app/app/lib/db-types.ts

@@ -36,7 +36,7 @@ export interface UserSettings {
     ownerRevolutProfileName?: string | null;
 };
 
-enum EmailStatus {
+export enum EmailStatus {
     /** Email is not yet verified - recipient has not yet confirmed their email address */
     Unverified = "unverified",
     /** Email is not yet verified - a verification request has been sent */