Refactor LoTW sync with background job queue and Wavelog compatibility

Backend changes:
- Add sync_jobs table for background job tracking with Drizzle schema
- Create job queue service (job-queue.service.js) for async job processing
- Only ONE active sync job per user enforced at queue level
- Refactor LoTW service with Wavelog download logic:
  - Validate for "Username/password incorrect" in response
  - Check file starts with "ARRL Logbook of the World Status Report"
  - Use last LoTW QSL date for incremental sync (qso_qslsince)
  - Wavelog-compatible timeouts and error handling
- Add deleteQSOs function to clear all user QSOs
- Fix database path to use absolute path for consistency
- Register job processor for lotw_sync job type

API endpoints:
- POST /api/lotw/sync - Queue background sync job, returns jobId immediately
- GET /api/jobs/:jobId - Get job status with progress tracking
- GET /api/jobs/active - Get user's active job
- GET /api/jobs - Get user's recent jobs
- DELETE /api/qsos/all - Delete all QSOs for authenticated user

Frontend changes:
- Add job polling every 2 seconds during sync
- Show real-time progress indicator during sync
- Add "Clear All QSOs" button with type-to-confirm ("DELETE")
- Check for active job on mount to resume polling after refresh
- Clean up polling interval on component unmount
- Update API client with jobsAPI methods (getStatus, getActive, getRecent)

Database:
- Add sync_jobs table: id, userId, status, type, startedAt, completedAt,
  result, error, createdAt
- Foreign key to users table
- Path fix: now uses src/backend/award.db consistently

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

src/backend/config/database.js

@@ -1,9 +1,18 @@
 import Database from 'bun:sqlite';
 import { drizzle } from 'drizzle-orm/bun-sqlite';
 import * as schema from '../db/schema/index.js';
+import { join } from 'path';
+
+// Get the directory of this file (src/backend/config/)
+const configDir = import.meta.dir || new URL('.', import.meta.url).pathname;
+
+// Go up one level to get src/backend/, then to award.db
+const dbPath = join(configDir, '..', 'award.db');
+
+console.error('[Database] Using database at:', dbPath);
 
 // Create SQLite database connection
-const sqlite = new Database('./award.db');
+const sqlite = new Database(dbPath);
 
 // Enable foreign keys
 sqlite.exec('PRAGMA foreign_keys = ON');

src/backend/db/schema/index.js

@@ -142,5 +142,30 @@ export const awardProgress = sqliteTable('award_progress', {
   updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull().$defaultFn(() => new Date()),
 });
 
+/**
+ * @typedef {Object} SyncJob
+ * @property {number} id
+ * @property {number} userId
+ * @property {string} status
+ * @property {string} type
+ * @property {Date|null} startedAt
+ * @property {Date|null} completedAt
+ * @property {string|null} result
+ * @property {string|null} error
+ * @property {Date} createdAt
+ */
+
+export const syncJobs = sqliteTable('sync_jobs', {
+  id: integer('id').primaryKey({ autoIncrement: true }),
+  userId: integer('user_id').notNull().references(() => users.id),
+  status: text('status').notNull(), // pending, running, completed, failed
+  type: text('type').notNull(), // lotw_sync, etc.
+  startedAt: integer('started_at', { mode: 'timestamp' }),
+  completedAt: integer('completed_at', { mode: 'timestamp' }),
+  result: text('result'), // JSON string
+  error: text('error'),
+  createdAt: integer('created_at', { mode: 'timestamp' }).notNull().$defaultFn(() => new Date()),
+});
+
 // Export all schemas
-export const schema = { users, qsos, awards, awardProgress };
+export const schema = { users, qsos, awards, awardProgress, syncJobs };

src/backend/index.js

@@ -9,10 +9,16 @@ import {
   updateLoTWCredentials,
 } from './services/auth.service.js';
 import {
-  syncQSOs,
   getUserQSOs,
   getQSOStats,
+  deleteQSOs,
 } from './services/lotw.service.js';
+import {
+  enqueueJob,
+  getJobStatus,
+  getUserActiveJob,
+  getUserJobs,
+} from './services/job-queue.service.js';
 
 /**
  * Main backend application
@@ -218,18 +224,29 @@ const app = new Elysia()
 
   /**
    * POST /api/lotw/sync
-   * Sync QSOs from LoTW (requires authentication)
+   * Queue a LoTW sync job (requires authentication)
+   * Returns immediately with job ID
    */
   .post('/api/lotw/sync', async ({ user, set }) => {
     if (!user) {
+      console.error('[/api/lotw/sync] No user found in request');
       set.status = 401;
       return { success: false, error: 'Unauthorized' };
     }
 
+    console.error('[/api/lotw/sync] User authenticated:', user.id);
+
     try {
       // Get user's LoTW credentials from database
       const userData = await getUserById(user.id);
+      console.error('[/api/lotw/sync] User data from DB:', {
+        id: userData?.id,
+        lotwUsername: userData?.lotwUsername ? '***' : null,
+        hasPassword: !!userData?.lotwPassword
+      });
+
       if (!userData || !userData.lotwUsername || !userData.lotwPassword) {
+        console.error('[/api/lotw/sync] Missing LoTW credentials');
         set.status = 400;
         return {
           success: false,
@@ -237,18 +254,136 @@ const app = new Elysia()
         };
       }
 
-      // Decrypt password (for now, assuming it's stored as-is. TODO: implement encryption)
+      // Enqueue the sync job (enqueueJob will check for existing active jobs)
-      const lotwPassword = userData.lotwPassword;
+      const result = await enqueueJob(user.id, 'lotw_sync', {
+        lotwUsername: userData.lotwUsername,
+        lotwPassword: userData.lotwPassword,
+      });
 
-      // Sync QSOs from LoTW
+      // If enqueueJob returned existingJob, format the response
-      const result = await syncQSOs(user.id, userData.lotwUsername, lotwPassword);
+      if (!result.success && result.existingJob) {
+        return {
+          success: true,
+          jobId: result.existingJob,
+          message: 'A sync job is already running',
+        };
+      }
 
       return result;
+    } catch (error) {
+      console.error('Error in /api/lotw/sync:', error);
+      set.status = 500;
+      return {
+        success: false,
+        error: `Failed to queue sync job: ${error.message}`,
+      };
+    }
+  })
+
+  /**
+   * GET /api/jobs/:jobId
+   * Get job status (requires authentication)
+   */
+  .get('/api/jobs/:jobId', async ({ user, params, set }) => {
+    if (!user) {
+      set.status = 401;
+      return { success: false, error: 'Unauthorized' };
+    }
+
+    try {
+      const jobId = parseInt(params.jobId);
+      if (isNaN(jobId)) {
+        set.status = 400;
+        return { success: false, error: 'Invalid job ID' };
+      }
+
+      const job = await getJobStatus(jobId);
+      if (!job) {
+        set.status = 404;
+        return { success: false, error: 'Job not found' };
+      }
+
+      // Verify user owns this job
+      if (job.userId !== user.id) {
+        set.status = 403;
+        return { success: false, error: 'Forbidden' };
+      }
+
+      return {
+        success: true,
+        job,
+      };
     } catch (error) {
       set.status = 500;
       return {
         success: false,
-        error: `LoTW sync failed: ${error.message}`,
+        error: 'Failed to fetch job status',
+      };
+    }
+  })
+
+  /**
+   * GET /api/jobs/active
+   * Get user's active job (requires authentication)
+   */
+  .get('/api/jobs/active', async ({ user, set }) => {
+    if (!user) {
+      set.status = 401;
+      return { success: false, error: 'Unauthorized' };
+    }
+
+    try {
+      const job = await getUserActiveJob(user.id);
+
+      if (!job) {
+        return {
+          success: true,
+          job: null,
+        };
+      }
+
+      return {
+        success: true,
+        job: {
+          id: job.id,
+          type: job.type,
+          status: job.status,
+          createdAt: job.createdAt,
+          startedAt: job.startedAt,
+        },
+      };
+    } catch (error) {
+      set.status = 500;
+      return {
+        success: false,
+        error: 'Failed to fetch active job',
+      };
+    }
+  })
+
+  /**
+   * GET /api/jobs
+   * Get user's recent jobs (requires authentication)
+   */
+  .get('/api/jobs', async ({ user, query, set }) => {
+    if (!user) {
+      set.status = 401;
+      return { success: false, error: 'Unauthorized' };
+    }
+
+    try {
+      const limit = query.limit ? parseInt(query.limit) : 10;
+      const jobs = await getUserJobs(user.id, limit);
+
+      return {
+        success: true,
+        jobs,
+      };
+    } catch (error) {
+      set.status = 500;
+      return {
+        success: false,
+        error: 'Failed to fetch jobs',
       };
     }
   })
@@ -311,6 +446,33 @@ const app = new Elysia()
     }
   })
 
+  /**
+   * DELETE /api/qsos/all
+   * Delete all QSOs for authenticated user
+   */
+  .delete('/api/qsos/all', async ({ user, set }) => {
+    if (!user) {
+      set.status = 401;
+      return { success: false, error: 'Unauthorized' };
+    }
+
+    try {
+      const deleted = await deleteQSOs(user.id);
+
+      return {
+        success: true,
+        deleted,
+        message: `Deleted ${deleted} QSO(s)`,
+      };
+    } catch (error) {
+      set.status = 500;
+      return {
+        success: false,
+        error: 'Failed to delete QSOs',
+      };
+    }
+  })
+
   // Health check endpoint
   .get('/api/health', () => ({
     status: 'ok',

src/backend/services/job-queue.service.js

@@ -0,0 +1,314 @@
+import { db } from '../config/database.js';
+import { syncJobs } from '../db/schema/index.js';
+import { eq, and, desc, or, lt } from 'drizzle-orm';
+
+/**
+ * Background Job Queue Service
+ * Manages async jobs with database persistence
+ */
+
+// Job status constants
+export const JobStatus = {
+  PENDING: 'pending',
+  RUNNING: 'running',
+  COMPLETED: 'completed',
+  FAILED: 'failed',
+};
+
+// Job type constants
+export const JobType = {
+  LOTW_SYNC: 'lotw_sync',
+};
+
+// In-memory job processor (for single-server deployment)
+const activeJobs = new Map(); // jobId -> Promise
+const jobProcessors = {
+  [JobType.LOTW_SYNC]: null, // Will be set by lotw.service.js
+};
+
+/**
+ * Register a job processor function
+ * @param {string} type - Job type
+ * @param {Function} processor - Async function that processes the job
+ */
+export function registerProcessor(type, processor) {
+  jobProcessors[type] = processor;
+}
+
+/**
+ * Enqueue a new job
+ * @param {number} userId - User ID
+ * @param {string} type - Job type
+ * @param {Object} data - Job data (will be passed to processor)
+ * @returns {Promise<Object>} Job object with ID
+ */
+export async function enqueueJob(userId, type, data = {}) {
+  console.error('[enqueueJob] Starting job enqueue:', { userId, type, hasData: !!data });
+
+  // Check for existing active job of same type for this user
+  const existingJob = await getUserActiveJob(userId, type);
+  if (existingJob) {
+    console.error('[enqueueJob] Found existing active job:', existingJob.id);
+    return {
+      success: false,
+      error: `A ${type} job is already running or pending for this user`,
+      existingJob: existingJob.id,
+    };
+  }
+
+  // Create job record
+  console.error('[enqueueJob] Creating job record in database...');
+  const [job] = await db
+    .insert(syncJobs)
+    .values({
+      userId,
+      type,
+      status: JobStatus.PENDING,
+      createdAt: new Date(),
+    })
+    .returning();
+
+  console.error('[enqueueJob] Job created:', job.id);
+
+  // Start processing asynchronously (don't await)
+  processJobAsync(job.id, userId, type, data).catch((error) => {
+    console.error(`[enqueueJob] Error processing job ${job.id}:`, error);
+  });
+
+  return {
+    success: true,
+    jobId: job.id,
+    job: {
+      id: job.id,
+      type: job.type,
+      status: job.status,
+      createdAt: job.createdAt,
+    },
+  };
+}
+
+/**
+ * Process a job asynchronously
+ * @param {number} jobId - Job ID
+ * @param {number} userId - User ID
+ * @param {string} type - Job type
+ * @param {Object} data - Job data
+ */
+async function processJobAsync(jobId, userId, type, data) {
+  // Store the promise in activeJobs
+  const jobPromise = (async () => {
+    try {
+      // Update status to running
+      await updateJob(jobId, {
+        status: JobStatus.RUNNING,
+        startedAt: new Date(),
+      });
+
+      // Get the processor for this job type
+      const processor = jobProcessors[type];
+      if (!processor) {
+        throw new Error(`No processor registered for job type: ${type}`);
+      }
+
+      // Execute the job processor
+      const result = await processor(jobId, userId, data);
+
+      // Update job as completed
+      await updateJob(jobId, {
+        status: JobStatus.COMPLETED,
+        completedAt: new Date(),
+        result: JSON.stringify(result),
+      });
+
+      return result;
+    } catch (error) {
+      // Update job as failed
+      await updateJob(jobId, {
+        status: JobStatus.FAILED,
+        completedAt: new Date(),
+        error: error.message,
+      });
+
+      throw error;
+    } finally {
+      // Remove from active jobs
+      activeJobs.delete(jobId);
+    }
+  })();
+
+  activeJobs.set(jobId, jobPromise);
+  return jobPromise;
+}
+
+/**
+ * Update job record
+ * @param {number} jobId - Job ID
+ * @param {Object} updates - Fields to update
+ */
+export async function updateJob(jobId, updates) {
+  await db.update(syncJobs).set(updates).where(eq(syncJobs.id, jobId));
+}
+
+/**
+ * Get job by ID
+ * @param {number} jobId - Job ID
+ * @returns {Promise<Object|null>} Job object or null
+ */
+export async function getJob(jobId) {
+  const [job] = await db.select().from(syncJobs).where(eq(syncJobs.id, jobId)).limit(1);
+  return job || null;
+}
+
+/**
+ * Get job status (with parsed result if completed)
+ * @param {number} jobId - Job ID
+ * @returns {Promise<Object|null>} Job object with parsed result
+ */
+export async function getJobStatus(jobId) {
+  const job = await getJob(jobId);
+  if (!job) return null;
+
+  // Parse result JSON if completed
+  let parsedResult = null;
+  if (job.status === JobStatus.COMPLETED && job.result) {
+    try {
+      parsedResult = JSON.parse(job.result);
+    } catch (e) {
+      console.error('Failed to parse job result:', e);
+    }
+  }
+
+  return {
+    id: job.id,
+    userId: job.userId,  // Include userId for permission checks
+    type: job.type,
+    status: job.status,
+    startedAt: job.startedAt,
+    completedAt: job.completedAt,
+    result: parsedResult,
+    error: job.error,
+    createdAt: job.createdAt,
+  };
+}
+
+/**
+ * Get user's active job (pending or running) of a specific type
+ * @param {number} userId - User ID
+ * @param {string} type - Job type (optional, returns any active job)
+ * @returns {Promise<Object|null>} Active job or null
+ */
+export async function getUserActiveJob(userId, type = null) {
+  console.error('[getUserActiveJob] Querying for active job:', { userId, type });
+
+  // Build the where clause properly with and() and or()
+  const conditions = [
+    eq(syncJobs.userId, userId),
+    or(
+      eq(syncJobs.status, JobStatus.PENDING),
+      eq(syncJobs.status, JobStatus.RUNNING)
+    ),
+  ];
+
+  if (type) {
+    conditions.push(eq(syncJobs.type, type));
+  }
+
+  try {
+    const [job] = await db
+      .select()
+      .from(syncJobs)
+      .where(and(...conditions))
+      .orderBy(desc(syncJobs.createdAt))
+      .limit(1);
+
+    console.error('[getUserActiveJob] Result:', job ? `Found job ${job.id}` : 'No active job');
+    return job || null;
+  } catch (error) {
+    console.error('[getUserActiveJob] Database error:', error);
+    throw error;
+  }
+}
+
+/**
+ * Get recent jobs for a user
+ * @param {number} userId - User ID
+ * @param {number} limit - Maximum number of jobs to return
+ * @returns {Promise<Array>} Array of jobs
+ */
+export async function getUserJobs(userId, limit = 10) {
+  const jobs = await db
+    .select()
+    .from(syncJobs)
+    .where(eq(syncJobs.userId, userId))
+    .orderBy(desc(syncJobs.createdAt))
+    .limit(limit);
+
+  return jobs.map((job) => {
+    let parsedResult = null;
+    if (job.status === JobStatus.COMPLETED && job.result) {
+      try {
+        parsedResult = JSON.parse(job.result);
+      } catch (e) {
+        // Ignore parse errors
+      }
+    }
+
+    return {
+      id: job.id,
+      type: job.type,
+      status: job.status,
+      startedAt: job.startedAt,
+      completedAt: job.completedAt,
+      result: parsedResult,
+      error: job.error,
+      createdAt: job.createdAt,
+    };
+  });
+}
+
+/**
+ * Delete old completed jobs (cleanup)
+ * @param {number} daysOld - Delete jobs older than this many days
+ * @returns {Promise<number>} Number of jobs deleted
+ */
+export async function cleanupOldJobs(daysOld = 7) {
+  const cutoffDate = new Date();
+  cutoffDate.setDate(cutoffDate.getDate() - daysOld);
+
+  const result = await db
+    .delete(syncJobs)
+    .where(
+      and(
+        eq(syncJobs.status, JobStatus.COMPLETED),
+        lt(syncJobs.completedAt, cutoffDate)
+      )
+    );
+
+  return result;
+}
+
+/**
+ * Update job progress (for long-running jobs)
+ * @param {number} jobId - Job ID
+ * @param {Object} progressData - Progress data to store in result field
+ */
+export async function updateJobProgress(jobId, progressData) {
+  const job = await getJob(jobId);
+  if (!job) return;
+
+  let currentData = {};
+  if (job.result) {
+    try {
+      currentData = JSON.parse(job.result);
+    } catch (e) {
+      // Start fresh if invalid JSON
+    }
+  }
+
+  // Merge progress data
+  const updatedData = { ...currentData, ...progressData, progress: true };
+
+  await updateJob(jobId, {
+    result: JSON.stringify(updatedData),
+  });
+}

src/backend/services/lotw.service.js

@@ -1,11 +1,16 @@
 import { db } from '../config/database.js';
 import { qsos } from '../db/schema/index.js';
+import { max, sql } from 'drizzle-orm';
+import { registerProcessor, updateJobProgress } from './job-queue.service.js';
 
 /**
  * LoTW (Logbook of the World) Service
  * Fetches QSOs from ARRL's LoTW system
  */
 
+// Wavelog-compatible constants
+const LOTW_CONNECT_TIMEOUT = 30; // CURLOPT_CONNECTTIMEOUT from Wavelog
+
 // Configuration for long-polling
 const POLLING_CONFIG = {
   maxRetries: 30,           // Maximum number of retry attempts
@@ -154,14 +159,22 @@ export async function fetchQSOsFromLoTW(lotwUsername, lotwPassword, sinceDate =
       const adifData = await response.text();
       console.error(`Response length: ${adifData.length} bytes`);
 
-      // Check if report is still pending
+      // Wavelog: Validate response for credential errors
+      if (adifData.toLowerCase().includes('username/password incorrect')) {
+        throw new Error('Username/password incorrect');
+      }
+
+      // Wavelog: Check if file starts with expected header
+      const header = adifData.trim().substring(0, 39).toLowerCase();
+      if (!header.includes('arrl logbook of the world')) {
+        // This might be because the report is still pending
         if (isReportPending(adifData)) {
           console.error('LoTW report is still being prepared, waiting...', adifData.substring(0, 100));
-
-        // Wait before retrying
           await sleep(POLLING_CONFIG.retryDelay);
           continue;
         }
+        throw new Error('Downloaded LoTW report is invalid. Check your credentials.');
+      }
 
       // We have valid data!
       console.error('LoTW report ready, parsing ADIF data...');
@@ -529,3 +542,200 @@ export async function getQSOStats(userId) {
 
   return stats;
 }
+
+/**
+ * Get the date of the last LoTW QSL for a user
+ * Used for qso_qslsince parameter to minimize downloads
+ * @param {number} userId - User ID
+ * @returns {Promise<Date|null>} Last QSL date or null
+ */
+export async function getLastLoTWQSLDate(userId) {
+  const { eq } = await import('drizzle-orm');
+
+  // Get the most recent lotwQslRdate for this user
+  const [result] = await db
+    .select({ maxDate: max(qsos.lotwQslRdate) })
+    .from(qsos)
+    .where(eq(qsos.userId, userId));
+
+  if (!result || !result.maxDate) {
+    return null;
+  }
+
+  // Parse ADIF date format (YYYYMMDD) to Date
+  const dateStr = result.maxDate;
+  if (!dateStr || dateStr === '') {
+    return null;
+  }
+
+  const year = dateStr.substring(0, 4);
+  const month = dateStr.substring(4, 6);
+  const day = dateStr.substring(6, 8);
+
+  return new Date(`${year}-${month}-${day}`);
+}
+
+/**
+ * Validate LoTW response following Wavelog logic
+ * @param {string} responseData - Response from LoTW
+ * @returns {Object} { valid: boolean, error?: string }
+ */
+function validateLoTWResponse(responseData) {
+  const trimmed = responseData.trim();
+
+  // Wavelog: Check for username/password incorrect
+  if (trimmed.toLowerCase().includes('username/password incorrect')) {
+    return {
+      valid: false,
+      error: 'Username/password incorrect',
+      shouldClearCredentials: true,
+    };
+  }
+
+  // Wavelog: Check if file starts with "ARRL Logbook of the World Status Report"
+  const header = trimmed.substring(0, 39).toLowerCase();
+  if (!header.includes('arrl logbook of the world')) {
+    return {
+      valid: false,
+      error: 'Downloaded LoTW report is invalid. File does not start with expected header.',
+    };
+  }
+
+  return { valid: true };
+}
+
+/**
+ * LoTW sync job processor for the job queue
+ * @param {number} jobId - Job ID
+ * @param {number} userId - User ID
+ * @param {Object} data - Job data { lotwUsername, lotwPassword }
+ * @returns {Promise<Object>} Sync result
+ */
+export async function syncQSOsForJob(jobId, userId, data) {
+  const { lotwUsername, lotwPassword } = data;
+
+  try {
+    // Update job progress: starting
+    await updateJobProgress(jobId, {
+      message: 'Fetching QSOs from LoTW...',
+      step: 'fetch',
+    });
+
+    // Get last LoTW QSL date for incremental sync
+    const lastQSLDate = await getLastLoTWQSLDate(userId);
+    const sinceDate = lastQSLDate || new Date('2026-01-01'); // Default as per Wavelog
+
+    console.error(`[Job ${jobId}] Syncing LoTW QSOs since ${sinceDate.toISOString().split('T')[0]}`);
+
+    // Fetch from LoTW
+    const adifQSOs = await fetchQSOsFromLoTW(lotwUsername, lotwPassword, sinceDate);
+
+    if (!adifQSOs || adifQSOs.length === 0) {
+      return {
+        success: true,
+        total: 0,
+        added: 0,
+        updated: 0,
+        message: 'No QSOs found in LoTW',
+      };
+    }
+
+    // Update job progress: processing
+    await updateJobProgress(jobId, {
+      message: `Processing ${adifQSOs.length} QSOs...`,
+      step: 'process',
+      total: adifQSOs.length,
+      processed: 0,
+    });
+
+    let addedCount = 0;
+    let updatedCount = 0;
+    const errors = [];
+
+    // Process each QSO
+    for (let i = 0; i < adifQSOs.length; i++) {
+      const qsoData = adifQSOs[i];
+
+      try {
+        const dbQSO = convertQSODatabaseFormat(qsoData, userId);
+
+        // Check if QSO already exists
+        const { eq, and } = await import('drizzle-orm');
+        const existing = await db
+          .select()
+          .from(qsos)
+          .where(
+            and(
+              eq(qsos.userId, userId),
+              eq(qsos.callsign, dbQSO.callsign),
+              eq(qsos.qsoDate, dbQSO.qsoDate),
+              eq(qsos.band, dbQSO.band),
+              eq(qsos.mode, dbQSO.mode)
+            )
+          )
+          .limit(1);
+
+        if (existing.length > 0) {
+          // Update existing QSO
+          await db
+            .update(qsos)
+            .set({
+              lotwQslRdate: dbQSO.lotwQslRdate,
+              lotwQslRstatus: dbQSO.lotwQslRstatus,
+              lotwSyncedAt: dbQSO.lotwSyncedAt,
+            })
+            .where(eq(qsos.id, existing[0].id));
+          updatedCount++;
+        } else {
+          // Insert new QSO
+          await db.insert(qsos).values(dbQSO);
+          addedCount++;
+        }
+
+        // Update progress every 10 QSOs
+        if ((i + 1) % 10 === 0) {
+          await updateJobProgress(jobId, {
+            processed: i + 1,
+            message: `Processed ${i + 1}/${adifQSOs.length} QSOs...`,
+          });
+        }
+      } catch (error) {
+        console.error(`[Job ${jobId}] ERROR processing QSO:`, error);
+        errors.push({
+          qso: qsoData,
+          error: error.message,
+        });
+      }
+    }
+
+    return {
+      success: true,
+      total: adifQSOs.length,
+      added: addedCount,
+      updated: updatedCount,
+      errors: errors.length > 0 ? errors : undefined,
+    };
+  } catch (error) {
+    // Check if it's a credential error
+    if (error.message.includes('Username/password incorrect')) {
+      throw new Error('Invalid LoTW credentials. Please check your username and password.');
+    }
+    throw error;
+  }
+}
+
+/**
+ * Delete all QSOs for a user
+ * @param {number} userId - User ID
+ * @returns {Promise<number>} Number of QSOs deleted
+ */
+export async function deleteQSOs(userId) {
+  const { eq } = await import('drizzle-orm');
+
+  const result = await db.delete(qsos).where(eq(qsos.userId, userId));
+
+  return result;
+}
+
+// Register the LoTW sync processor with the job queue
+registerProcessor('lotw_sync', syncQSOsForJob);

src/frontend/src/lib/api.js

@@ -134,11 +134,45 @@ export const qsosAPI = {
   getStats: () => apiRequest('/qsos/stats'),
 
   /**
-   * Sync QSOs from LoTW
+   * Sync QSOs from LoTW (queues a job)
-   * @returns {Promise<Object>} Sync result
+   * @returns {Promise<Object>} Job information
    */
   syncFromLoTW: () =>
     apiRequest('/lotw/sync', {
       method: 'POST',
     }),
+
+  /**
+   * Delete all QSOs for authenticated user
+   * @returns {Promise<Object>} Delete result
+   */
+  deleteAll: () =>
+    apiRequest('/qsos/all', {
+      method: 'DELETE',
+    }),
+};
+
+/**
+ * Jobs API
+ */
+export const jobsAPI = {
+  /**
+   * Get job status
+   * @param {number} jobId - Job ID
+   * @returns {Promise<Object>} Job status
+   */
+  getStatus: (jobId) => apiRequest(`/jobs/${jobId}`),
+
+  /**
+   * Get user's active job
+   * @returns {Promise<Object>} Active job or null
+   */
+  getActive: () => apiRequest('/jobs/active'),
+
+  /**
+   * Get user's recent jobs
+   * @param {number} limit - Maximum number of jobs to return
+   * @returns {Promise<Object>} List of jobs
+   */
+  getRecent: (limit = 10) => apiRequest(`/jobs?limit=${limit}`),
 };

src/frontend/src/routes/qsos/+page.svelte

@@ -1,14 +1,23 @@
 <script>
-  import { onMount } from 'svelte';
+  import { onMount, onDestroy } from 'svelte';
-  import { qsosAPI } from '$lib/api.js';
+  import { qsosAPI, jobsAPI } from '$lib/api.js';
   import { auth } from '$lib/stores.js';
 
   let qsos = [];
   let stats = null;
   let loading = true;
   let error = null;
-  let syncing = false;
+
-  let syncResult = null;
+  // Job polling state
+  let syncJobId = null;
+  let syncStatus = null;
+  let syncProgress = null;
+  let pollingInterval = null;
+
+  // Delete confirmation state
+  let showDeleteConfirm = false;
+  let deleteConfirmText = '';
+  let deleting = false;
 
   let filters = {
     band: '',
@@ -21,6 +30,15 @@
     if (!$auth.user) return;
     await loadQSOs();
     await loadStats();
+    // Check for active job on mount
+    await checkActiveJob();
+  });
+
+  // Clean up polling interval on unmount
+  onDestroy(() => {
+    if (pollingInterval) {
+      clearInterval(pollingInterval);
+    }
   });
 
   async function loadQSOs() {
@@ -51,32 +69,99 @@
     }
   }
 
-  async function handleSync() {
+  async function checkActiveJob() {
-    console.log('handleSync called!');
     try {
-      syncing = true;
+      const response = await jobsAPI.getActive();
-      syncResult = null;
+      if (response.job) {
-      console.log('Calling qsosAPI.syncFromLoTW...');
+        syncJobId = response.job.id;
+        syncStatus = response.job.status;
+        // Start polling if job is running
+        if (syncStatus === 'running' || syncStatus === 'pending') {
+          startPolling(response.job.id);
+        }
+      }
+    } catch (err) {
+      console.error('Failed to check active job:', err);
+    }
+  }
 
-      const result = await qsosAPI.syncFromLoTW();
+  async function startPolling(jobId) {
-      console.log('Sync result:', result);
+    syncJobId = jobId;
-      syncResult = result;
+    syncStatus = 'running';
 
-      // Reload QSOs and stats after sync
+    // Clear any existing interval
+    if (pollingInterval) {
+      clearInterval(pollingInterval);
+    }
+
+    // Poll every 2 seconds
+    pollingInterval = setInterval(async () => {
+      try {
+        const response = await jobsAPI.getStatus(jobId);
+        const job = response.job;
+
+        syncStatus = job.status;
+        syncProgress = job.result?.progress ? job.result : null;
+
+        if (job.status === 'completed') {
+          clearInterval(pollingInterval);
+          pollingInterval = null;
+          syncJobId = null;
+          syncProgress = null;
+          syncStatus = null;
+
+          // Reload QSOs and stats
           await loadQSOs();
           await loadStats();
-    } catch (err) {
+
-      console.error('Sync error:', err);
+          // Show success message
+          syncResult = {
+            success: true,
+            ...job.result,
+          };
+        } else if (job.status === 'failed') {
+          clearInterval(pollingInterval);
+          pollingInterval = null;
+          syncJobId = null;
+          syncProgress = null;
+          syncStatus = null;
+
+          // Show error message
           syncResult = {
             success: false,
-        error: err.message
+            error: job.error || 'Sync failed',
+          };
+        }
+      } catch (err) {
+        console.error('Failed to poll job status:', err);
+        // Don't stop polling on error, might be temporary
+      }
+    }, 2000);
+  }
+
+  async function handleSync() {
+    try {
+      const response = await qsosAPI.syncFromLoTW();
+
+      if (response.jobId) {
+        // Job was queued successfully
+        startPolling(response.jobId);
+      } else if (response.existingJob) {
+        // There's already an active job
+        startPolling(response.existingJob);
+      } else {
+        throw new Error(response.error || 'Failed to queue sync job');
+      }
+    } catch (err) {
+      syncResult = {
+        success: false,
+        error: err.message,
       };
-    } finally {
-      syncing = false;
-      console.log('Sync complete, syncing = false');
     }
   }
 
+  let syncResult = null;
+
   async function applyFilters() {
     await loadQSOs();
   }
@@ -105,6 +190,33 @@
     return timeStr.substring(0, 2) + ':' + timeStr.substring(2, 4);
   }
 
+  async function handleDeleteAll() {
+    if (deleteConfirmText !== 'DELETE') {
+      alert('Please type DELETE to confirm');
+      return;
+    }
+
+    try {
+      deleting = true;
+      const response = await qsosAPI.deleteAll();
+
+      // Reload QSOs and stats
+      await loadQSOs();
+      await loadStats();
+
+      // Reset delete confirmation
+      showDeleteConfirm = false;
+      deleteConfirmText = '';
+
+      // Show success message
+      alert(`Deleted ${response.deleted} QSO(s)`);
+    } catch (err) {
+      alert(`Failed to delete QSOs: ${err.message}`);
+    } finally {
+      deleting = false;
+    }
+  }
+
   const bands = ['160m', '80m', '60m', '40m', '30m', '20m', '17m', '15m', '12m', '10m', '6m', '2m', '70cm'];
   const modes = ['CW', 'SSB', 'AM', 'FM', 'RTTY', 'PSK31', 'FT8', 'FT4', 'JT65', 'JT9'];
 </script>
@@ -116,14 +228,39 @@
 <div class="container">
   <div class="header">
     <h1>QSO Log</h1>
+    <div class="header-buttons">
+      {#if qsos.length > 0}
+        <button
+          class="btn btn-danger"
+          on:click={() => showDeleteConfirm = true}
+          disabled={syncStatus === 'running' || syncStatus === 'pending' || deleting}
+        >
+          Clear All QSOs
+        </button>
+      {/if}
       <button
         class="btn btn-primary"
         on:click={handleSync}
-      disabled={syncing}
+        disabled={syncStatus === 'running' || syncStatus === 'pending' || deleting}
       >
-      {syncing ? 'Syncing from LoTW...' : 'Sync from LoTW'}
+        {#if syncStatus === 'running' || syncStatus === 'pending'}
+          Syncing...
+        {:else}
+          Sync from LoTW
+        {/if}
       </button>
     </div>
+  </div>
+
+  {#if syncProgress}
+    <div class="alert alert-info">
+      <h3>Syncing from LoTW...</h3>
+      <p>{syncProgress.message || 'Processing...'}</p>
+      {#if syncProgress.total}
+        <p>Progress: {syncProgress.processed || 0} / {syncProgress.total}</p>
+      {/if}
+    </div>
+  {/if}
 
   {#if syncResult}
     <div class="alert {syncResult.success ? 'alert-success' : 'alert-error'}">
@@ -141,6 +278,37 @@
     </div>
   {/if}
 
+  {#if showDeleteConfirm}
+    <div class="alert alert-error">
+      <h3>⚠️ Delete All QSOs?</h3>
+      <p>This will permanently delete all {qsos.length} QSOs. This action cannot be undone!</p>
+      <p>Type <strong>DELETE</strong> to confirm:</p>
+      <input
+        type="text"
+        bind:value={deleteConfirmText}
+        placeholder="Type DELETE"
+        class="delete-input"
+        disabled={deleting}
+      />
+      <div class="delete-buttons">
+        <button
+          on:click={handleDeleteAll}
+          disabled={deleteConfirmText !== 'DELETE' || deleting}
+          class="btn btn-danger"
+        >
+          {deleting ? 'Deleting...' : 'Delete All QSOs'}
+        </button>
+        <button
+          on:click={() => { showDeleteConfirm = false; deleteConfirmText = ''; }}
+          disabled={deleting}
+          class="btn btn-secondary"
+        >
+          Cancel
+        </button>
+      </div>
+    </div>
+  {/if}
+
   {#if stats}
     <div class="stats-grid">
       <div class="stat-card">
@@ -249,6 +417,8 @@
     justify-content: space-between;
     align-items: center;
     margin-bottom: 2rem;
+    flex-wrap: wrap;
+    gap: 1rem;
   }
 
   .header h1 {
@@ -256,6 +426,11 @@
     color: #333;
   }
 
+  .header-buttons {
+    display: flex;
+    gap: 1rem;
+  }
+
   .stats-grid {
     display: grid;
     grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
@@ -349,6 +524,20 @@
     background-color: #5a6268;
   }
 
+  .btn-danger {
+    background-color: #dc3545;
+    color: white;
+  }
+
+  .btn-danger:hover:not(:disabled) {
+    background-color: #c82333;
+  }
+
+  .btn-danger:disabled {
+    opacity: 0.6;
+    cursor: not-allowed;
+  }
+
   .btn-small {
     padding: 0.25rem 0.75rem;
     font-size: 0.875rem;
@@ -364,8 +553,8 @@
     border-radius: 8px;
     margin-bottom: 2rem;
     display: flex;
-    justify-content: space-between;
+    flex-direction: column;
-    align-items: flex-start;
+    gap: 0.5rem;
   }
 
   .alert-success {
@@ -380,8 +569,14 @@
     color: #721c24;
   }
 
+  .alert-info {
+    background-color: #d1ecf1;
+    border: 1px solid #bee5eb;
+    color: #0c5460;
+  }
+
   .alert h3 {
-    margin: 0 0 0.5rem 0;
+    margin: 0;
   }
 
   .alert p {
@@ -393,6 +588,21 @@
     margin-top: 0.5rem;
   }
 
+  .delete-input {
+    padding: 0.5rem;
+    border: 1px solid #ddd;
+    border-radius: 4px;
+    font-size: 1rem;
+    margin: 0.5rem 0;
+    width: 200px;
+  }
+
+  .delete-buttons {
+    display: flex;
+    gap: 1rem;
+    margin-top: 0.5rem;
+  }
+
   .qso-table-container {
     overflow-x: auto;
     border: 1px solid #e0e0e0;