Initial commit: LAAPC Print Service - Windows service with multi-tray printing, IPC queue management, PDF testing support, and self-installing CLI

2026-05-14 16:59:59 -05:00
commit cce9248089
23 changed files with 2974 additions and 0 deletions
@@ -0,0 +1,167 @@
+using Microsoft.Extensions.Options;
+using PrintService.Models;
+using System.Collections.Concurrent;
+using System.Text.Json;
+
+namespace PrintService.Services;
+
+/// <summary>
+/// Manages the print job queue with persistence
+/// </summary>
+public class PrintQueueService
+{
+    private readonly ConcurrentQueue<PrintJob> _queue = new();
+    private readonly AppSettings _settings;
+    private readonly ILogger<PrintQueueService> _logger;
+    private readonly SemaphoreSlim _semaphore = new(1, 1);
+
+    public PrintQueueService(IOptions<AppSettings> settings, ILogger<PrintQueueService> logger)
+    {
+        _settings = settings.Value;
+        _logger = logger;
+        LoadQueueState();
+    }
+
+    /// <summary>
+    /// Enqueue a new print job
+    /// </summary>
+    public void Enqueue(PrintJob job)
+    {
+        _queue.Enqueue(job);
+        _logger.LogInformation("Job {JobId} enqueued for document type: {DocType}", job.Id, job.DocumentType);
+        SaveQueueState();
+    }
+
+    /// <summary>
+    /// Try to dequeue the next pending job
+    /// </summary>
+    public bool TryDequeue(out PrintJob? job)
+    {
+        bool result = _queue.TryDequeue(out job);
+        if (result && job != null)
+        {
+            _logger.LogInformation("Job {JobId} dequeued", job.Id);
+            SaveQueueState();
+        }
+        return result;
+    }
+
+    /// <summary>
+    /// Peek at the next job without removing it
+    /// </summary>
+    public bool TryPeek(out PrintJob? job)
+    {
+        return _queue.TryPeek(out job);
+    }
+
+    /// <summary>
+    /// Get count of jobs in queue
+    /// </summary>
+    public int Count => _queue.Count;
+
+    /// <summary>
+    /// Save queue state to disk
+    /// </summary>
+    private void SaveQueueState()
+    {
+        try
+        {
+            _semaphore.Wait();
+            var jobs = _queue.ToArray();
+            var json = JsonSerializer.Serialize(jobs, new JsonSerializerOptions { WriteIndented = true });
+            File.WriteAllText(_settings.QueueStateFile, json);
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Failed to save queue state");
+        }
+        finally
+        {
+            _semaphore.Release();
+        }
+    }
+
+    /// <summary>
+    /// Load queue state from disk
+    /// </summary>
+    private void LoadQueueState()
+    {
+        try
+        {
+            if (File.Exists(_settings.QueueStateFile))
+            {
+                var json = File.ReadAllText(_settings.QueueStateFile);
+                var jobs = JsonSerializer.Deserialize<PrintJob[]>(json);
+                
+                if (jobs != null)
+                {
+                    foreach (var job in jobs)
+                    {
+                        // Only reload pending or retry-scheduled jobs
+                        if (job.Status == PrintJobStatus.Pending || job.Status == PrintJobStatus.RetryScheduled)
+                        {
+                            _queue.Enqueue(job);
+                        }
+                    }
+                    _logger.LogInformation("Loaded {Count} jobs from queue state", _queue.Count);
+                }
+            }
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Failed to load queue state");
+        }
+    }
+
+    /// <summary>
+    /// Requeue a job (for retry)
+    /// </summary>
+    public void Requeue(PrintJob job)
+    {
+        job.RetryCount++;
+        job.Status = PrintJobStatus.RetryScheduled;
+        job.UpdatedAt = DateTime.Now;
+        
+        if (job.RetryCount >= _settings.MaxRetryAttempts)
+        {
+            _logger.LogWarning("Job {JobId} exceeded max retries, moving to error folder", job.Id);
+            MoveToErrorFolder(job);
+        }
+        else
+        {
+            _logger.LogInformation("Requeueing job {JobId}, attempt {Retry}", job.Id, job.RetryCount);
+            _queue.Enqueue(job);
+            SaveQueueState();
+        }
+    }
+
+    /// <summary>
+    /// Move a failed job to error folder
+    /// </summary>
+    private void MoveToErrorFolder(PrintJob job)
+    {
+        try
+        {
+            var errorFileName = Path.Combine(_settings.ErrorPath, 
+                $"{Path.GetFileNameWithoutExtension(job.OriginalFilename)}_{job.Id}.txt");
+            
+            if (File.Exists(job.QueuedFilePath))
+            {
+                File.Move(job.QueuedFilePath, errorFileName);
+            }
+            
+            // Save error details
+            var errorInfo = Path.Combine(_settings.ErrorPath, 
+                $"{Path.GetFileNameWithoutExtension(job.OriginalFilename)}_{job.Id}_error.json");
+            var json = JsonSerializer.Serialize(job, new JsonSerializerOptions { WriteIndented = true });
+            File.WriteAllText(errorInfo, json);
+            
+            job.Status = PrintJobStatus.Failed;
+            SaveQueueState();
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Failed to move job {JobId} to error folder", job.Id);
+        }
+    }
+}