feat: AI job tracking, range support, auto-prompt, and resume

- New `ai_jobs` PocketBase collection tracks all long-running AI tasks
  (batch-covers, chapter-names) with status, progress, and cancellation
- `handlers_aijobs.go`: GET/cancel endpoints for ai_jobs; centralised
  cancel registry (moved from handlers_catalogue)
- Batch-covers and chapter-names SSE handlers now create/resume ai_job
  records, support from_item/to_item ranges, and resume from items_done
  on restart via job_id
- New `POST /api/admin/image-gen/auto-prompt`: generates an image prompt
  from book description (cover) or chapter title (chapter) via LLM
- image-gen page: "Auto-prompt" button calls auto-prompt API when a slug
  is selected; falls back gracefully if TextGen not configured
- text-gen chapter-names: from/to chapter range inputs + job ID display
- catalogue-tools batch-covers: from/to item range + resume job ID input
- pb-init-v3.sh: adds ai_jobs collection (idempotent)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/internal/backend/handlers_aijobs.go

@@ -0,0 +1,233 @@
+package backend
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/libnovel/backend/internal/cfai"
+	"github.com/libnovel/backend/internal/domain"
+)
+
+// ── Cancel registry ────────────────────────────────────────────────────────────
+// cancelJobsMu guards cancelJobs.
+var cancelJobsMu sync.Mutex
+
+// cancelJobs maps a job ID to its CancelFunc. Entries are added when a batch
+// job starts and removed when it finishes or is cancelled.
+var cancelJobs = map[string]context.CancelFunc{}
+
+func registerCancelJob(id string, cancel context.CancelFunc) {
+	cancelJobsMu.Lock()
+	cancelJobs[id] = cancel
+	cancelJobsMu.Unlock()
+}
+
+func deregisterCancelJob(id string) {
+	cancelJobsMu.Lock()
+	delete(cancelJobs, id)
+	cancelJobsMu.Unlock()
+}
+
+// ── AI Job list / get / cancel ─────────────────────────────────────────────────
+
+// handleAdminListAIJobs handles GET /api/admin/ai-jobs.
+// Returns all ai_job records sorted by started descending.
+func (s *Server) handleAdminListAIJobs(w http.ResponseWriter, r *http.Request) {
+	if s.deps.AIJobStore == nil {
+		jsonError(w, http.StatusServiceUnavailable, "ai job store not configured")
+		return
+	}
+	jobs, err := s.deps.AIJobStore.ListAIJobs(r.Context())
+	if err != nil {
+		s.deps.Log.Error("admin: list ai jobs failed", "err", err)
+		jsonError(w, http.StatusInternalServerError, "list ai jobs: "+err.Error())
+		return
+	}
+	writeJSON(w, 0, map[string]any{"jobs": jobs})
+}
+
+// handleAdminGetAIJob handles GET /api/admin/ai-jobs/{id}.
+func (s *Server) handleAdminGetAIJob(w http.ResponseWriter, r *http.Request) {
+	if s.deps.AIJobStore == nil {
+		jsonError(w, http.StatusServiceUnavailable, "ai job store not configured")
+		return
+	}
+	id := r.PathValue("id")
+	job, ok, err := s.deps.AIJobStore.GetAIJob(r.Context(), id)
+	if err != nil {
+		jsonError(w, http.StatusInternalServerError, err.Error())
+		return
+	}
+	if !ok {
+		jsonError(w, http.StatusNotFound, fmt.Sprintf("job %q not found", id))
+		return
+	}
+	writeJSON(w, 0, job)
+}
+
+// handleAdminCancelAIJob handles POST /api/admin/ai-jobs/{id}/cancel.
+// Marks the job as cancelled in PB and cancels the in-memory context if present.
+func (s *Server) handleAdminCancelAIJob(w http.ResponseWriter, r *http.Request) {
+	if s.deps.AIJobStore == nil {
+		jsonError(w, http.StatusServiceUnavailable, "ai job store not configured")
+		return
+	}
+	id := r.PathValue("id")
+
+	// Cancel in-memory context if the job is still running in this process.
+	cancelJobsMu.Lock()
+	if cancel, ok := cancelJobs[id]; ok {
+		cancel()
+	}
+	cancelJobsMu.Unlock()
+
+	// Mark as cancelled in PB.
+	if err := s.deps.AIJobStore.UpdateAIJob(r.Context(), id, map[string]any{
+		"status":   string(domain.TaskStatusCancelled),
+		"finished": time.Now().Format(time.RFC3339),
+	}); err != nil {
+		s.deps.Log.Error("admin: cancel ai job failed", "id", id, "err", err)
+		jsonError(w, http.StatusInternalServerError, "cancel ai job: "+err.Error())
+		return
+	}
+
+	s.deps.Log.Info("admin: ai job cancelled", "id", id)
+	writeJSON(w, 0, map[string]any{"cancelled": true})
+}
+
+// ── Auto-prompt ────────────────────────────────────────────────────────────────
+
+// autoPromptRequest is the JSON body for POST /api/admin/image-gen/auto-prompt.
+type autoPromptRequest struct {
+	// Slug is the book slug.
+	Slug string `json:"slug"`
+	// Type is "cover" or "chapter".
+	Type string `json:"type"`
+	// Chapter number (required when type == "chapter").
+	Chapter int `json:"chapter"`
+	// Model is the text-gen model to use. Defaults to DefaultTextModel.
+	Model string `json:"model"`
+}
+
+// autoPromptResponse is returned by POST /api/admin/image-gen/auto-prompt.
+type autoPromptResponse struct {
+	Prompt string `json:"prompt"`
+	Model  string `json:"model"`
+}
+
+// handleAdminImageGenAutoPrompt handles POST /api/admin/image-gen/auto-prompt.
+//
+// Uses the text generation model to create a vivid image generation prompt
+// based on the book's description (for covers) or chapter title/content (for chapters).
+func (s *Server) handleAdminImageGenAutoPrompt(w http.ResponseWriter, r *http.Request) {
+	if s.deps.TextGen == nil {
+		jsonError(w, http.StatusServiceUnavailable, "text generation not configured")
+		return
+	}
+
+	var req autoPromptRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		jsonError(w, http.StatusBadRequest, "parse body: "+err.Error())
+		return
+	}
+	if strings.TrimSpace(req.Slug) == "" {
+		jsonError(w, http.StatusBadRequest, "slug is required")
+		return
+	}
+	if req.Type != "cover" && req.Type != "chapter" {
+		jsonError(w, http.StatusBadRequest, `type must be "cover" or "chapter"`)
+		return
+	}
+
+	meta, ok, err := s.deps.BookReader.ReadMetadata(r.Context(), req.Slug)
+	if err != nil {
+		jsonError(w, http.StatusInternalServerError, "read metadata: "+err.Error())
+		return
+	}
+	if !ok {
+		jsonError(w, http.StatusNotFound, fmt.Sprintf("book %q not found", req.Slug))
+		return
+	}
+
+	model := req.Model
+	if model == "" {
+		model = string(cfai.DefaultTextModel)
+	}
+
+	var userPrompt string
+	if req.Type == "cover" {
+		userPrompt = fmt.Sprintf(
+			"Book: \"%s\"\nAuthor: %s\nGenres: %s\n\nDescription:\n%s",
+			meta.Title,
+			meta.Author,
+			strings.Join(meta.Genres, ", "),
+			meta.Summary,
+		)
+	} else {
+		// For chapter images, use chapter title if available.
+		chapterTitle := fmt.Sprintf("Chapter %d", req.Chapter)
+		if req.Chapter > 0 {
+			chapters, listErr := s.deps.BookReader.ListChapters(r.Context(), req.Slug)
+			if listErr == nil {
+				for _, ch := range chapters {
+					if ch.Number == req.Chapter {
+						chapterTitle = ch.Title
+						break
+					}
+				}
+			}
+		}
+		userPrompt = fmt.Sprintf(
+			"Book: \"%s\"\nGenres: %s\nChapter: %s\n\nBook description:\n%s",
+			meta.Title,
+			strings.Join(meta.Genres, ", "),
+			chapterTitle,
+			meta.Summary,
+		)
+	}
+
+	systemPrompt := buildAutoPromptSystem(req.Type)
+
+	s.deps.Log.Info("admin: image auto-prompt requested",
+		"slug", req.Slug, "type", req.Type, "chapter", req.Chapter, "model", model)
+
+	result, genErr := s.deps.TextGen.Generate(r.Context(), cfai.TextRequest{
+		Model: cfai.TextModel(model),
+		Messages: []cfai.TextMessage{
+			{Role: "system", Content: systemPrompt},
+			{Role: "user", Content: userPrompt},
+		},
+		MaxTokens: 256,
+	})
+	if genErr != nil {
+		s.deps.Log.Error("admin: auto-prompt failed", "err", genErr)
+		jsonError(w, http.StatusBadGateway, "text generation failed: "+genErr.Error())
+		return
+	}
+
+	writeJSON(w, 0, autoPromptResponse{
+		Prompt: strings.TrimSpace(result),
+		Model:  model,
+	})
+}
+
+func buildAutoPromptSystem(imageType string) string {
+	if imageType == "cover" {
+		return `You are a professional prompt engineer for AI image generation (Stable Diffusion / FLUX models). ` +
+			`Given a book's title, genres, and description, write a single vivid image generation prompt ` +
+			`for a book cover. The prompt should describe the visual composition, art style, lighting, ` +
+			`and mood without mentioning text or typography. ` +
+			`Format: comma-separated visual descriptors, 30–60 words. ` +
+			`Output ONLY the prompt — no explanation, no quotes, no labels.`
+	}
+	return `You are a professional prompt engineer for AI image generation (Stable Diffusion / FLUX models). ` +
+		`Given a book's title, genres, and a specific chapter title, write a single vivid scene illustration prompt. ` +
+		`Describe the scene, characters, setting, lighting, and art style. ` +
+		`Format: comma-separated visual descriptors, 30–60 words. ` +
+		`Output ONLY the prompt — no explanation, no quotes, no labels.`
+}

backend/internal/backend/handlers_catalogue.go

@@ -16,32 +16,12 @@ import (
 	"fmt"
 	"net/http"
 	"strings"
-	"sync"
+	"time"
 
 	"github.com/libnovel/backend/internal/cfai"
 	"github.com/libnovel/backend/internal/domain"
 )
 
-// ── Cancel registry ────────────────────────────────────────────────────────
-
-// cancelJobsMu guards cancelJobs.
-var cancelJobsMu sync.Mutex
-
-// cancelJobs maps a job ID to its CancelFunc. Entries are added when a batch
-// job starts and removed when it finishes or is cancelled.
-var cancelJobs = map[string]context.CancelFunc{}
-
-func registerCancelJob(id string, cancel context.CancelFunc) {
-	cancelJobsMu.Lock()
-	cancelJobs[id] = cancel
-	cancelJobsMu.Unlock()
-}
-
-func deregisterCancelJob(id string) {
-	cancelJobsMu.Lock()
-	delete(cancelJobs, id)
-	cancelJobsMu.Unlock()
-}
 
 // ── Tagline ───────────────────────────────────────────────────────────────
 
@@ -452,8 +432,9 @@ type batchCoverEvent struct {
 // Streams SSE events as it generates covers for every book that has no cover
 // stored in MinIO. Each event carries progress info. The final event has Finish=true.
 //
-// The job can be cancelled by calling POST /api/admin/catalogue/batch-covers/cancel
-// with body {"job_id":"..."}.
+// Supports from_item/to_item to process a sub-range of the catalogue (0-based indices).
+// Supports job_id to resume a previously interrupted job.
+// The job can be cancelled by calling POST /api/admin/ai-jobs/{id}/cancel.
 func (s *Server) handleAdminBatchCovers(w http.ResponseWriter, r *http.Request) {
 	if s.deps.TextGen == nil || s.deps.ImageGen == nil {
 		jsonError(w, http.StatusServiceUnavailable, "image/text generation not configured")
@@ -469,22 +450,34 @@ func (s *Server) handleAdminBatchCovers(w http.ResponseWriter, r *http.Request)
 		NumSteps int    `json:"num_steps"`
 		Width    int    `json:"width"`
 		Height   int    `json:"height"`
+		FromItem int    `json:"from_item"`
+		ToItem   int    `json:"to_item"`
+		JobID    string `json:"job_id"`
 	}
 	// Body is optional — defaults used if absent.
 	json.NewDecoder(r.Body).Decode(&reqBody) //nolint:errcheck
 
-	books, err := s.deps.BookReader.ListBooks(r.Context())
+	allBooks, err := s.deps.BookReader.ListBooks(r.Context())
 	if err != nil {
 		jsonError(w, http.StatusInternalServerError, "list books: "+err.Error())
 		return
 	}
 
-	// Generate a unique job ID.
-	jobID := randomHex(8)
-	ctx, cancel := context.WithCancel(r.Context())
-	registerCancelJob(jobID, cancel)
-	defer deregisterCancelJob(jobID)
-	defer cancel()
+	// Apply range filter.
+	books := allBooks
+	if reqBody.FromItem > 0 || reqBody.ToItem > 0 {
+		from := reqBody.FromItem
+		to := reqBody.ToItem
+		if to == 0 || to >= len(allBooks) {
+			to = len(allBooks) - 1
+		}
+		if from < 0 {
+			from = 0
+		}
+		if from <= to && from < len(allBooks) {
+			books = allBooks[from : to+1]
+		}
+	}
 
 	// SSE headers.
 	w.Header().Set("Content-Type", "text/event-stream")
@@ -503,19 +496,75 @@ func (s *Server) handleAdminBatchCovers(w http.ResponseWriter, r *http.Request)
 	total := len(books)
 	done := 0
 
-	// Send initial event with jobID so frontend can store it for cancellation.
-	sseWrite(batchCoverEvent{JobID: jobID, Done: 0, Total: total})
+	// Create or resume PB ai_job and register cancel context.
+	var pbJobID string
+	resumeFrom := 0
+	ctx, cancel := context.WithCancel(r.Context())
+	defer cancel()
 
-	for _, book := range books {
+	if s.deps.AIJobStore != nil {
+		if reqBody.JobID != "" {
+			if existing, ok, _ := s.deps.AIJobStore.GetAIJob(r.Context(), reqBody.JobID); ok {
+				pbJobID = reqBody.JobID
+				resumeFrom = existing.ItemsDone
+				done = resumeFrom
+				_ = s.deps.AIJobStore.UpdateAIJob(r.Context(), pbJobID, map[string]any{
+					"status":      string(domain.TaskStatusRunning),
+					"items_total": total,
+				})
+			}
+		}
+		if pbJobID == "" {
+			id, createErr := s.deps.AIJobStore.CreateAIJob(r.Context(), domain.AIJob{
+				Kind:       "batch-covers",
+				Status:     domain.TaskStatusRunning,
+				FromItem:   reqBody.FromItem,
+				ToItem:     reqBody.ToItem,
+				ItemsTotal: total,
+				Started:    time.Now(),
+			})
+			if createErr == nil {
+				pbJobID = id
+			}
+		}
+		if pbJobID != "" {
+			registerCancelJob(pbJobID, cancel)
+			defer deregisterCancelJob(pbJobID)
+		}
+	}
+
+	// Use pbJobID as the SSE job_id when available, else a random hex fallback.
+	sseJobID := pbJobID
+	if sseJobID == "" {
+		sseJobID = randomHex(8)
+		ctx2, cancel2 := context.WithCancel(r.Context())
+		registerCancelJob(sseJobID, cancel2)
+		defer deregisterCancelJob(sseJobID)
+		defer cancel2()
+		cancel() // replace ctx with ctx2
+		ctx = ctx2
+	}
+
+	// Send initial event with jobID so frontend can store it for cancellation.
+	sseWrite(batchCoverEvent{JobID: sseJobID, Done: done, Total: total})
+
+	for i, book := range books {
 		if ctx.Err() != nil {
 			break
 		}
+		// Skip already-processed items when resuming.
+		if i < resumeFrom {
+			continue
+		}
 
 		// Check if cover already exists.
 		hasCover := s.deps.CoverStore.CoverExists(ctx, book.Slug)
 		if hasCover {
 			done++
 			sseWrite(batchCoverEvent{Done: done, Total: total, Slug: book.Slug, Skipped: true})
+			if pbJobID != "" && s.deps.AIJobStore != nil {
+				_ = s.deps.AIJobStore.UpdateAIJob(r.Context(), pbJobID, map[string]any{"items_done": done})
+			}
 			continue
 		}
 
@@ -547,6 +596,21 @@ func (s *Server) handleAdminBatchCovers(w http.ResponseWriter, r *http.Request)
 		done++
 		s.deps.Log.Info("batch-covers: cover generated", "slug", book.Slug)
 		sseWrite(batchCoverEvent{Done: done, Total: total, Slug: book.Slug})
+		if pbJobID != "" && s.deps.AIJobStore != nil {
+			_ = s.deps.AIJobStore.UpdateAIJob(r.Context(), pbJobID, map[string]any{"items_done": done})
+		}
+	}
+
+	if pbJobID != "" && s.deps.AIJobStore != nil {
+		status := domain.TaskStatusDone
+		if ctx.Err() != nil {
+			status = domain.TaskStatusCancelled
+		}
+		_ = s.deps.AIJobStore.UpdateAIJob(r.Context(), pbJobID, map[string]any{
+			"status":     string(status),
+			"items_done": done,
+			"finished":   time.Now().Format(time.RFC3339),
+		})
 	}
 
 	sseWrite(batchCoverEvent{Done: done, Total: total, Finish: true})

backend/internal/backend/handlers_textgen.go

@@ -1,10 +1,12 @@
 package backend
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"net/http"
 	"strings"
+	"time"
 
 	"github.com/libnovel/backend/internal/cfai"
 	"github.com/libnovel/backend/internal/domain"
@@ -38,6 +40,13 @@ type textGenChapterNamesRequest struct {
 	Model string `json:"model"`
 	// MaxTokens limits response length (0 = model default).
 	MaxTokens int `json:"max_tokens"`
+	// FromChapter is the first chapter to process (1-based). 0 = start from chapter 1.
+	FromChapter int `json:"from_chapter"`
+	// ToChapter is the last chapter to process (inclusive). 0 = process all.
+	ToChapter int `json:"to_chapter"`
+	// JobID is an optional existing ai_job ID for resuming a previous run.
+	// If set, the handler resumes from items_done instead of starting from scratch.
+	JobID string `json:"job_id"`
 }
 
 // proposedChapterTitle is a single chapter with its AI-proposed title.
@@ -51,6 +60,8 @@ type proposedChapterTitle struct {
 
 // chapterNamesBatchEvent is one SSE event emitted per processed batch.
 type chapterNamesBatchEvent struct {
+	// JobID is the PB ai_job ID for this run (emitted on the first event only).
+	JobID string `json:"job_id,omitempty"`
 	// Batch is the 1-based batch index.
 	Batch int `json:"batch"`
 	// TotalBatches is the total number of batches.
@@ -99,16 +110,36 @@ func (s *Server) handleAdminTextGenChapterNames(w http.ResponseWriter, r *http.R
 	}
 
 	// Load existing chapter list.
-	chapters, err := s.deps.BookReader.ListChapters(r.Context(), req.Slug)
+	allChapters, err := s.deps.BookReader.ListChapters(r.Context(), req.Slug)
 	if err != nil {
 		jsonError(w, http.StatusInternalServerError, "list chapters: "+err.Error())
 		return
 	}
-	if len(chapters) == 0 {
+	if len(allChapters) == 0 {
 		jsonError(w, http.StatusNotFound, fmt.Sprintf("no chapters found for slug %q", req.Slug))
 		return
 	}
 
+	// Apply chapter range filter.
+	chapters := allChapters
+	if req.FromChapter > 0 || req.ToChapter > 0 {
+		filtered := chapters[:0]
+		for _, ch := range allChapters {
+			if req.FromChapter > 0 && ch.Number < req.FromChapter {
+				continue
+			}
+			if req.ToChapter > 0 && ch.Number > req.ToChapter {
+				break
+			}
+			filtered = append(filtered, ch)
+		}
+		chapters = filtered
+	}
+	if len(chapters) == 0 {
+		jsonError(w, http.StatusBadRequest, "no chapters in the specified range")
+		return
+	}
+
 	model := cfai.TextModel(req.Model)
 	if model == "" {
 		model = cfai.DefaultTextModel
@@ -160,10 +191,58 @@ func (s *Server) handleAdminTextGenChapterNames(w http.ResponseWriter, r *http.R
 		}
 	}
 
-	chaptersDone := 0
+	// Create or resume an ai_job record for tracking.
+	var jobID string
+	resumeFrom := 0
+	jobCtx := r.Context()
+	var jobCancel context.CancelFunc
+
+	if s.deps.AIJobStore != nil {
+		if req.JobID != "" {
+			if existingJob, ok, _ := s.deps.AIJobStore.GetAIJob(r.Context(), req.JobID); ok {
+				jobID = req.JobID
+				resumeFrom = existingJob.ItemsDone
+				_ = s.deps.AIJobStore.UpdateAIJob(r.Context(), jobID, map[string]any{
+					"status":      string(domain.TaskStatusRunning),
+					"items_total": len(chapters),
+				})
+			}
+		}
+		if jobID == "" {
+			jobPayload := fmt.Sprintf(`{"pattern":%q}`, req.Pattern)
+			id, createErr := s.deps.AIJobStore.CreateAIJob(r.Context(), domain.AIJob{
+				Kind:       "chapter-names",
+				Slug:       req.Slug,
+				Status:     domain.TaskStatusRunning,
+				FromItem:   req.FromChapter,
+				ToItem:     req.ToChapter,
+				ItemsTotal: len(chapters),
+				Model:      string(model),
+				Payload:    jobPayload,
+				Started:    time.Now(),
+			})
+			if createErr == nil {
+				jobID = id
+			}
+		}
+		if jobID != "" {
+			jobCtx, jobCancel = context.WithCancel(r.Context())
+			registerCancelJob(jobID, jobCancel)
+			defer deregisterCancelJob(jobID)
+			defer jobCancel()
+		}
+	}
+
+	chaptersDone := resumeFrom
+	firstEvent := true
 	for i, batch := range batches {
-		if r.Context().Err() != nil {
-			return // client disconnected
+		if jobCtx.Err() != nil {
+			return // client disconnected or cancelled
+		}
+		// Skip batches already processed in a previous run.
+		batchEnd := (i + 1) * chapterNamesBatchSize
+		if batchEnd <= resumeFrom {
+			continue
 		}
 
 		var chapterListSB strings.Builder
@@ -172,7 +251,7 @@ func (s *Server) handleAdminTextGenChapterNames(w http.ResponseWriter, r *http.R
 		}
 		userPrompt := fmt.Sprintf("Naming pattern: %s\n\nChapters:\n%s", req.Pattern, chapterListSB.String())
 
-		raw, genErr := s.deps.TextGen.Generate(r.Context(), cfai.TextRequest{
+		raw, genErr := s.deps.TextGen.Generate(jobCtx, cfai.TextRequest{
 			Model: model,
 			Messages: []cfai.TextMessage{
 				{Role: "system", Content: systemPrompt},
@@ -183,14 +262,19 @@ func (s *Server) handleAdminTextGenChapterNames(w http.ResponseWriter, r *http.R
 		if genErr != nil {
 			s.deps.Log.Error("admin: text-gen chapter-names batch failed",
 				"batch", i+1, "err", genErr)
-			sseWrite(chapterNamesBatchEvent{
+			evt := chapterNamesBatchEvent{
 				Batch:         i + 1,
 				TotalBatches:  totalBatches,
 				ChaptersDone:  chaptersDone,
 				TotalChapters: len(chapters),
 				Model:         string(model),
 				Error:         genErr.Error(),
-			})
+			}
+			if firstEvent {
+				evt.JobID = jobID
+				firstEvent = false
+			}
+			sseWrite(evt)
 			continue
 		}
 
@@ -205,13 +289,37 @@ func (s *Server) handleAdminTextGenChapterNames(w http.ResponseWriter, r *http.R
 		}
 		chaptersDone += len(batch)
 
-		sseWrite(chapterNamesBatchEvent{
+		if jobID != "" && s.deps.AIJobStore != nil {
+			_ = s.deps.AIJobStore.UpdateAIJob(r.Context(), jobID, map[string]any{
+				"items_done": chaptersDone,
+			})
+		}
+
+		evt := chapterNamesBatchEvent{
 			Batch:         i + 1,
 			TotalBatches:  totalBatches,
 			ChaptersDone:  chaptersDone,
 			TotalChapters: len(chapters),
 			Model:         string(model),
 			Chapters:      result,
+		}
+		if firstEvent {
+			evt.JobID = jobID
+			firstEvent = false
+		}
+		sseWrite(evt)
+	}
+
+	// Mark job as done in PB.
+	if jobID != "" && s.deps.AIJobStore != nil {
+		status := domain.TaskStatusDone
+		if jobCtx.Err() != nil {
+			status = domain.TaskStatusCancelled
+		}
+		_ = s.deps.AIJobStore.UpdateAIJob(r.Context(), jobID, map[string]any{
+			"status":     string(status),
+			"items_done": chaptersDone,
+			"finished":   time.Now().Format(time.RFC3339),
 		})
 	}
 

backend/internal/backend/server.go

@@ -82,6 +82,9 @@ type Dependencies struct {
 	// BookWriter writes book metadata and chapter refs to PocketBase.
 	// Used by admin text-gen apply endpoints.
 	BookWriter bookstore.BookWriter
+	// AIJobStore tracks long-running AI generation jobs in PocketBase.
+	// If nil, job persistence is disabled (jobs still run but are not recorded).
+	AIJobStore bookstore.AIJobStore
 	// Log is the structured logger.
 	Log *slog.Logger
 }
@@ -214,6 +217,14 @@ func (s *Server) ListenAndServe(ctx context.Context) error {
 	mux.HandleFunc("POST /api/admin/catalogue/batch-covers/cancel", s.handleAdminBatchCoversCancel)
 	mux.HandleFunc("POST /api/admin/catalogue/refresh-metadata/{slug}", s.handleAdminRefreshMetadata)
 
+	// Admin AI job tracking endpoints
+	mux.HandleFunc("GET /api/admin/ai-jobs", s.handleAdminListAIJobs)
+	mux.HandleFunc("GET /api/admin/ai-jobs/{id}", s.handleAdminGetAIJob)
+	mux.HandleFunc("POST /api/admin/ai-jobs/{id}/cancel", s.handleAdminCancelAIJob)
+
+	// Auto-prompt generation from book/chapter content
+	mux.HandleFunc("POST /api/admin/image-gen/auto-prompt", s.handleAdminImageGenAutoPrompt)
+
 	// Admin data repair endpoints
 	mux.HandleFunc("POST /api/admin/dedup-chapters/{slug}", s.handleDedupChapters)