package main

import (
	"encoding/base64"
	"encoding/csv"
	"encoding/json"
	"fmt"
	"html/template"
	"io"
	"log"
	"net/http"
	"os"
	"path/filepath"
	"strings"
	"time"

	"github.com/go-chi/chi/v5"
	"github.com/go-chi/chi/v5/middleware"
)

var (
	tmplFuncs    template.FuncMap
	documentsDir string
	recordsDir   string
	storeDir     string
	indexDir     string
	inboxDir     string
)

func initPaths() {
	documentsDir = os.Getenv("DOCSYS_DATA_DIR")
	if documentsDir == "" {
		documentsDir = "/srv/docsys"
	}
	recordsDir = filepath.Join(documentsDir, "records")
	storeDir = filepath.Join(documentsDir, "store")
	indexDir = filepath.Join(documentsDir, "index")
	inboxDir = filepath.Join(documentsDir, "inbox")
}

var categories = []string{
	"taxes", "bills", "medical", "insurance", "legal",
	"financial", "expenses", "vehicles", "home", "personal", "contacts",
	"inou", "sophia", "uncategorized",
}

func main() {
	initPaths()

	// Initialize database
	dbPath := filepath.Join(indexDir, "docsys.db")
	if err := InitDB(dbPath); err != nil {
		log.Fatalf("Failed to initialize database: %v", err)
	}
	defer CloseDB()

	// Note: Markdown record indexing disabled - we now store directly in DB
	// if err := IndexDocumentsFromDirectory(recordsDir, storeDir, categories); err != nil {
	// 	log.Printf("Warning: Failed to index documents: %v", err)
	// }

	// Ensure inbox directory exists
	os.MkdirAll(inboxDir, 0755)

	// Template functions
	tmplFuncs = template.FuncMap{
		"truncate":     truncateText,
		"categoryIcon": categoryIcon,
		"formatDate":   formatDate,
		"formatDateTime": formatDateTime,
		"lower":        strings.ToLower,
		"title":        strings.Title,
		"safe":         func(s string) template.HTML { return template.HTML(s) },
		"multiply":     func(a float64, b float64) float64 { return a * b },
		"isImage": func(filename string) bool {
			ext := strings.ToLower(filepath.Ext(filename))
			return ext == ".jpg" || ext == ".jpeg" || ext == ".png" || ext == ".gif" || ext == ".webp" || ext == ".tiff"
		},
	}

	r := chi.NewRouter()
	r.Use(middleware.Logger)
	r.Use(middleware.Recoverer)
	r.Use(middleware.Compress(5))

	// Static files
	r.Handle("/static/*", http.StripPrefix("/static/", http.FileServer(http.Dir("static"))))

	// PDF serving
	r.Get("/pdf/{hash}", servePDF)
	r.Get("/img/{hash}", serveImage)

	// Pages
	r.Get("/", dashboardHandler)
	r.Get("/browse", browseHandler)
	r.Get("/browse/{category}", browseCategoryHandler)
	r.Get("/document/{id}", documentHandler)
	r.Get("/search", searchHandler)

	// API endpoints
	r.Get("/api/search", apiSearchMDHandler)
	r.Post("/api/search", apiSearchHandler)
	r.Get("/api/documents", apiDocumentsHandler)
	r.Get("/api/processing", apiProcessingHandler)
	r.Post("/api/upload", uploadHandler)
	r.Post("/api/ingest", ingestHandler)
	r.Put("/api/document/{id}", updateDocumentHandler)
	r.Delete("/api/document/{id}", deleteDocumentHandler)
	r.Get("/api/export", exportCSVHandler)
	r.Post("/api/share/{id}", createShareHandler)
	r.Delete("/api/share/{token}", deleteShareHandler)
	r.Get("/api/shares/{id}", listSharesHandler)
	r.Get("/s/{token}", publicShareHandler)
	r.Post("/api/reindex", reindexHandler)
	r.Get("/api/debug/stats", debugStatsHandler)

	// Watch inbox directory for new files (scanner via SFTP, web upload, etc.)
	StartInboxWatcher()

	port := ":9201"
	log.Printf("🗂️  DocSys starting on http://localhost%s", port)
	log.Printf("📁 Documents: %s", documentsDir)
	log.Fatal(http.ListenAndServe(port, r))
}

// Template helpers

func truncateText(s string, n int) string {
	if len(s) <= n {
		return s
	}
	return s[:n] + "..."
}

func categoryIcon(cat string) string {
	icons := map[string]string{
		"taxes":         "📋",
		"bills":         "💰",
		"medical":       "🏥",
		"insurance":     "🛡️",
		"legal":         "⚖️",
		"financial":     "🏦",
		"expenses":      "💳",
		"vehicles":      "🚗",
		"home":          "🏠",
		"personal":      "👤",
		"contacts":      "📇",
		"inou":          "🏢",
		"sophia":        "👧",
		"uncategorized": "📁",
	}
	if icon, ok := icons[cat]; ok {
		return icon
	}
	return "📄"
}

func formatDate(s string) string {
	formats := []string{
		"2006-01-02T15:04:05.999999",
		"2006-01-02T15:04:05",
		"2006-01-02",
		"January 2, 2006",
		"january 2, 2006",
	}
	for _, f := range formats {
		if t, err := time.Parse(f, s); err == nil {
			return t.Format("Jan 2, 2006")
		}
	}
	return s
}

func formatDateTime(s string) string {
	formats := []string{
		"2006-01-02T15:04:05-07:00",
		"2006-01-02T15:04:05.999999-07:00",
		"2006-01-02T15:04:05.999999",
		"2006-01-02T15:04:05",
		"2006-01-02 15:04:05",
		"2006-01-02",
	}
	loc, _ := time.LoadLocation("America/New_York")
	if loc == nil {
		loc = time.UTC
	}
	for _, f := range formats {
		if t, err := time.Parse(f, s); err == nil {
			t = t.In(loc)
			return t.Format("Jan 02, 2006 3:04 PM MST")
		}
	}
	return s
}

// Template rendering

func renderTemplate(w http.ResponseWriter, name string, data interface{}) {
	tmpl := template.Must(template.New("").Funcs(tmplFuncs).ParseFiles(
		"templates/base.html",
		"templates/"+name+".html",
	))
	if err := tmpl.ExecuteTemplate(w, "base", data); err != nil {
		log.Printf("Template error: %v", err)
		http.Error(w, "Template error", http.StatusInternalServerError)
	}
}

func renderPartial(w http.ResponseWriter, name string, data interface{}) {
	tmpl := template.Must(template.New("").Funcs(tmplFuncs).ParseFiles(
		"templates/partials/" + name + ".html",
	))
	if err := tmpl.ExecuteTemplate(w, "partials/"+name+".html", data); err != nil {
		log.Printf("Template error: %v", err)
		http.Error(w, "Template error", http.StatusInternalServerError)
	}
}

// Page handlers

func dashboardHandler(w http.ResponseWriter, r *http.Request) {
	stats, _ := GetStats()
	renderTemplate(w, "dashboard", map[string]interface{}{
		"Title":      "Dashboard",
		"Stats":      stats,
		"Categories": categories,
	})
}

func browseHandler(w http.ResponseWriter, r *http.Request) {
	renderTemplate(w, "browse", map[string]interface{}{
		"Title":      "Browse Documents",
		"Categories": categories,
		"CatStats":   GetCategoryStats(categories),
	})
}

func browseCategoryHandler(w http.ResponseWriter, r *http.Request) {
	category := chi.URLParam(r, "category")
	docs, _ := GetDocumentsByCategory(category)
	renderTemplate(w, "category", map[string]interface{}{
		"Title":     strings.Title(category),
		"Category":  category,
		"Documents": docs,
	})
}

func documentHandler(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	doc, err := GetDocument(id)
	if err != nil {
		http.Error(w, "Document not found", http.StatusNotFound)
		return
	}
	renderTemplate(w, "document", map[string]interface{}{
		"Title":      doc.Title,
		"Document":   doc,
		"Categories": categories,
	})
}

func searchHandler(w http.ResponseWriter, r *http.Request) {
	query := r.URL.Query().Get("q")
	var docs []Document
	if query != "" {
		// Try FTS first
		docs, _ = SearchDocuments(query, 50)
		// If no keyword results, try semantic search
		if len(docs) == 0 {
			if emb, err := GenerateEmbedding(query); err == nil {
				docs, _ = SemanticSearch(emb, 10)
			}
		}
	}
	renderTemplate(w, "search", map[string]interface{}{
		"Title":     "Search",
		"Query":     query,
		"Documents": docs,
	})
}

func servePDF(w http.ResponseWriter, r *http.Request) {
	hash := chi.URLParam(r, "hash")
	download := r.URL.Query().Get("download") == "1"

	// Try PDF first, then TXT, then bare
	for _, ext := range []string{".pdf", ".txt", ""} {
		path := filepath.Join(storeDir, hash+ext)
		fi, err := os.Stat(path)
		if err != nil {
			continue
		}

		if download {
			filename := hash + ext
			if doc, err := GetDocument(hash); err == nil && doc.Title != "" {
				filename = sanitizeFilename(doc.Title)
				if ext != "" && !strings.HasSuffix(strings.ToLower(filename), ext) {
					filename += ext
				}
			}
			f, err := os.Open(path)
			if err != nil {
				http.Error(w, "Cannot read file", http.StatusInternalServerError)
				return
			}
			defer f.Close()
			if ext == ".pdf" || ext == "" {
				w.Header().Set("Content-Type", "application/pdf")
			} else {
				w.Header().Set("Content-Type", "text/plain")
			}
			w.Header().Set("Content-Disposition", fmt.Sprintf(`attachment; filename="%s"`, filename))
			w.Header().Set("Content-Length", fmt.Sprintf("%d", fi.Size()))
			io.Copy(w, f)
			return
		}

		// Inline viewing
		if ext == ".pdf" || ext == "" {
			w.Header().Set("Content-Type", "application/pdf")
		} else {
			w.Header().Set("Content-Type", "text/plain")
		}
		http.ServeFile(w, r, path)
		return
	}

	http.Error(w, "File not found", http.StatusNotFound)
}

func serveImage(w http.ResponseWriter, r *http.Request) {
	hash := chi.URLParam(r, "hash")
	mimeTypes := map[string]string{
		".jpg": "image/jpeg", ".jpeg": "image/jpeg",
		".png": "image/png", ".gif": "image/gif",
		".webp": "image/webp", ".tiff": "image/tiff",
	}
	for ext, mime := range mimeTypes {
		path := filepath.Join(storeDir, hash+ext)
		if _, err := os.Stat(path); err == nil {
			w.Header().Set("Content-Type", mime)
			w.Header().Set("Cache-Control", "private, max-age=3600")
			http.ServeFile(w, r, path)
			return
		}
	}
	http.NotFound(w, r)
}


// sanitizeFilename removes characters unsafe for use in Content-Disposition filenames.
func sanitizeFilename(name string) string {
	replacer := strings.NewReplacer(`"`, "'", "/", "-", "\\", "-", "\n", " ", "\r", "")
	return replacer.Replace(name)
}

// API handlers

func apiSearchHandler(w http.ResponseWriter, r *http.Request) {
	query := r.FormValue("q")
	if query == "" {
		w.Write([]byte(""))
		return
	}

	docs, err := SearchDocuments(query, 50)
	if err != nil {
		// Fallback to simple search
		docs, _ = SearchDocumentsFallback(query, 50)
	}

	renderPartial(w, "document-list", docs)
}

// apiSearchMDHandler handles GET /api/search?q={query}&format=md
// Returns all matching documents as concatenated plain-text markdown,
// one document per section separated by ---. Intended for AI/LLM consumption.
func apiSearchMDHandler(w http.ResponseWriter, r *http.Request) {
	query := r.URL.Query().Get("q")
	format := r.URL.Query().Get("format")

	// Only serve markdown format; anything else falls back to a 400
	if format != "md" {
		http.Error(w, "format=md required", http.StatusBadRequest)
		return
	}
	if query == "" {
		http.Error(w, "q parameter required", http.StatusBadRequest)
		return
	}

	docs, err := SearchDocuments(query, 200)
	if err != nil {
		docs, _ = SearchDocumentsFallback(query, 200)
	}

	w.Header().Set("Content-Type", "text/markdown; charset=utf-8")

	if len(docs) == 0 {
		w.Write([]byte("No documents found matching: " + query + "\n"))
		return
	}

	var sb strings.Builder
	for i, doc := range docs {
		sb.WriteString("# Document: ")
		if doc.Title != "" {
			sb.WriteString(doc.Title)
		} else {
			sb.WriteString("(untitled)")
		}
		sb.WriteString("\n")
		sb.WriteString("ID: ")
		sb.WriteString(doc.ID)
		if doc.Category != "" {
			sb.WriteString(" | Category: ")
			sb.WriteString(doc.Category)
		}
		if doc.Date != "" {
			sb.WriteString(" | Date: ")
			sb.WriteString(doc.Date)
		}
		if doc.Vendor != "" {
			sb.WriteString(" | Vendor: ")
			sb.WriteString(doc.Vendor)
		}
		sb.WriteString("\n\n")

		text := doc.FullText
		if text == "" {
			text = doc.Summary
		}
		if text != "" {
			sb.WriteString(text)
			sb.WriteString("\n")
		}

		if i < len(docs)-1 {
			sb.WriteString("\n---\n\n")
		}
	}

	w.Write([]byte(sb.String()))
}

func apiProcessingHandler(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(GetActiveJobs())
}

func apiDocumentsHandler(w http.ResponseWriter, r *http.Request) {
	category := r.URL.Query().Get("category")
	var docs []Document
	if category != "" {
		docs, _ = GetDocumentsByCategory(category)
	} else {
		docs, _ = GetAllDocuments()
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(docs)
}

func uploadHandler(w http.ResponseWriter, r *http.Request) {
	r.ParseMultipartForm(32 << 20) // 32MB max

	file, header, err := r.FormFile("file")
	if err != nil {
		http.Error(w, "Failed to read file", http.StatusBadRequest)
		return
	}
	defer file.Close()

	// Save to inbox
	filename := fmt.Sprintf("%d_%s", time.Now().Unix(), header.Filename)
	destPath := filepath.Join(inboxDir, filename)

	dest, err := os.Create(destPath)
	if err != nil {
		http.Error(w, "Failed to save file", http.StatusInternalServerError)
		return
	}
	defer dest.Close()

	io.Copy(dest, file)

	// Check for duplicate before processing
	hash, _ := FileHash(destPath)
	existingDoc, _ := GetDocument(hash)

	if existingDoc != nil && existingDoc.Status != "processing" {
		// Document already exists — remove inbox file, return existing
		os.Remove(destPath)
		w.Header().Set("Content-Type", "application/json")
		json.NewEncoder(w).Encode(map[string]interface{}{
			"status":   "duplicate",
			"filename": filename,
			"message":  "Document already exists in your library.",
			"document": map[string]string{
				"id":       existingDoc.ID,
				"title":    existingDoc.Title,
				"category": existingDoc.Category,
			},
		})
		return
	}

	// Create pending document immediately (shows in UI right away)
	InsertPendingDocument(hash, header.Filename)

	// Process document (async)
	go func() {
		if doc, err := ProcessDocument(destPath); err != nil {
			log.Printf("Process error for %s: %v", filename, err)
			UpdateDocumentStatus(hash, "error")
		} else {
			log.Printf("Processed: %s → %s/%s", filename, doc.Category, doc.ID)
		}
	}()

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]interface{}{
		"status":   "success",
		"filename": filename,
		"id":       hash,
		"message":  "Processing...",
	})
}

// ingestHandler accepts JSON with base64-encoded file content
// POST /api/ingest
// {
//   "filename": "invoice.pdf",
//   "content": "<base64-encoded-data>",
//   "source": "email",           // optional metadata
//   "subject": "Your invoice",   // optional
//   "from": "billing@example.com" // optional
// }
func ingestHandler(w http.ResponseWriter, r *http.Request) {
	var req struct {
		Filename string `json:"filename"`
		Content  string `json:"content"`
		URL      string `json:"url"`
		Source   string `json:"source"`
		Subject  string `json:"subject"`
		From     string `json:"from"`
	}

	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, "Invalid JSON", http.StatusBadRequest)
		return
	}

	var data []byte

	if req.URL != "" {
		// Fetch from URL
		resp, err := http.Get(req.URL)
		if err != nil {
			http.Error(w, "Failed to fetch URL: "+err.Error(), http.StatusBadGateway)
			return
		}
		defer resp.Body.Close()
		if resp.StatusCode >= 400 {
			http.Error(w, fmt.Sprintf("URL returned %d", resp.StatusCode), http.StatusBadGateway)
			return
		}
		data, err = io.ReadAll(resp.Body)
		if err != nil {
			http.Error(w, "Failed to read URL content", http.StatusInternalServerError)
			return
		}
		// Derive filename from URL or content-type if not provided
		if req.Filename == "" {
			ext := ""
			ct := resp.Header.Get("Content-Type")
			switch {
			case strings.Contains(ct, "jpeg") || strings.Contains(ct, "jpg"):
				ext = ".jpg"
			case strings.Contains(ct, "png"):
				ext = ".png"
			case strings.Contains(ct, "gif"):
				ext = ".gif"
			case strings.Contains(ct, "webp"):
				ext = ".webp"
			case strings.Contains(ct, "pdf"):
				ext = ".pdf"
			case strings.Contains(ct, "tiff"):
				ext = ".tiff"
			default:
				// Try to get extension from URL path
				urlPath := resp.Request.URL.Path
				if e := filepath.Ext(urlPath); e != "" {
					ext = e
				} else {
					ext = ".bin"
				}
			}
			// Use last path segment of URL as base name
			base := filepath.Base(resp.Request.URL.Path)
			if base == "." || base == "/" {
				base = "url-import"
			}
			if filepath.Ext(base) == "" {
				base += ext
			}
			req.Filename = base
		}
	} else {
		if req.Filename == "" || req.Content == "" {
			http.Error(w, "filename and content required, or provide url", http.StatusBadRequest)
			return
		}
		// Decode base64 content
		var err error
		data, err = base64.StdEncoding.DecodeString(req.Content)
		if err != nil {
			http.Error(w, "Invalid base64 content", http.StatusBadRequest)
			return
		}
	}

	// Sanitize filename
	safeName := strings.ReplaceAll(req.Filename, "/", "_")
	safeName = strings.ReplaceAll(safeName, "\\", "_")

	// Generate unique filename with timestamp
	filename := fmt.Sprintf("%d_%s", time.Now().Unix(), safeName)
	destPath := filepath.Join(inboxDir, filename)

	// Write file
	if err := os.WriteFile(destPath, data, 0644); err != nil {
		http.Error(w, "Failed to write file", http.StatusInternalServerError)
		return
	}

	// Process immediately (async)
	go func() {
		if doc, err := ProcessDocument(destPath); err != nil {
			log.Printf("Process error for %s: %v", filename, err)
		} else {
			// Store email metadata if provided
			if req.Source != "" || req.Subject != "" || req.From != "" {
				doc.Metadata = map[string]string{
					"source":  req.Source,
					"subject": req.Subject,
					"from":    req.From,
				}
				UpdateDocumentMetadata(doc.ID, doc.Metadata)
			}
			log.Printf("Processed: %s → %s/%s", filename, doc.Category, doc.ID)
		}
	}()

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]string{
		"status":   "success",
		"filename": filename,
		"message":  "Document ingested. Processing started.",
	})
}

func updateDocumentHandler(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")

	var update struct {
		Title    string `json:"title"`
		Category string `json:"category"`
		Notes    string `json:"notes"`
	}

	if err := json.NewDecoder(r.Body).Decode(&update); err != nil {
		http.Error(w, "Invalid request", http.StatusBadRequest)
		return
	}

	// Get current document to check if category changed
	doc, err := GetDocument(id)
	if err != nil {
		http.Error(w, "Document not found", http.StatusNotFound)
		return
	}

	// Update in database
	if err := UpdateDocument(id, DocumentUpdate{
		Title:    update.Title,
		Category: update.Category,
		Notes:    update.Notes,
	}); err != nil {
		http.Error(w, "Failed to update", http.StatusInternalServerError)
		return
	}

	// Move file if category changed
	if doc.Category != update.Category && doc.RecordPath != "" {
		newDir := filepath.Join(recordsDir, update.Category)
		os.MkdirAll(newDir, 0755)
		newPath := filepath.Join(newDir, filepath.Base(doc.RecordPath))
		if err := os.Rename(doc.RecordPath, newPath); err == nil {
			UpdateDocumentRecordPath(id, newPath)
		}
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]string{"status": "success"})
}

func deleteDocumentHandler(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")

	doc, err := GetDocument(id)
	if err != nil {
		http.Error(w, "Document not found", http.StatusNotFound)
		return
	}

	// Delete from database (includes FTS and embeddings)
	DeleteDocument(id)

	// Delete record file
	if doc.RecordPath != "" {
		os.Remove(doc.RecordPath)
	}

	// Delete store files (PDF/TXT)
	for _, ext := range []string{".pdf", ".txt", ""} {
		path := filepath.Join(storeDir, id+ext)
		os.Remove(path) // ignore errors for non-existent files
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]string{"status": "deleted"})
}

func exportCSVHandler(w http.ResponseWriter, r *http.Request) {
	category := r.URL.Query().Get("category")
	var docs []Document
	if category != "" {
		docs, _ = GetDocumentsByCategory(category)
	} else {
		docs, _ = GetAllDocuments()
	}

	w.Header().Set("Content-Type", "text/csv")
	w.Header().Set("Content-Disposition", "attachment; filename=documents.csv")

	writer := csv.NewWriter(w)
	writer.Write([]string{"ID", "Title", "Category", "Type", "Date", "Amount", "Vendor", "Summary"})

	for _, doc := range docs {
		writer.Write([]string{
			doc.ID, doc.Title, doc.Category, doc.Type,
			doc.Date, doc.Amount, doc.Vendor, doc.Summary,
		})
	}
	writer.Flush()
}

func debugStatsHandler(w http.ResponseWriter, r *http.Request) {
	stats, err := GetStats()
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]interface{}{
		"error":         err,
		"total":         stats.TotalDocs,
		"recent":        stats.RecentDocs,
		"uploadsCount":  len(stats.RecentUploads),
		"recentUploads": stats.RecentUploads,
	})
}

func createShareHandler(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	var req struct {
		Days int `json:"days"`
	}
	req.Days = 7 // default
	json.NewDecoder(r.Body).Decode(&req)

	token, err := CreateShare(id, req.Days)
	if err != nil {
		http.Error(w, "Failed to create share", http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]string{
		"token": token,
		"url":   "/s/" + token + ".pdf",
	})
}

func deleteShareHandler(w http.ResponseWriter, r *http.Request) {
	token := chi.URLParam(r, "token")
	DeleteShare(token)
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]string{"status": "deleted"})
}

func listSharesHandler(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	shares, err := GetSharesByDocument(id)
	if err != nil {
		shares = []Share{}
	}
	if shares == nil {
		shares = []Share{}
	}
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(shares)
}

func publicShareHandler(w http.ResponseWriter, r *http.Request) {
	token := chi.URLParam(r, "token")
	token = strings.TrimSuffix(token, ".pdf")
	doc, err := GetShare(token)
	if err != nil || doc == nil {
		http.Error(w, "Not found", http.StatusNotFound)
		return
	}

	// Serve the PDF directly
	for _, ext := range []string{".pdf", ".txt", ""} {
		path := filepath.Join(storeDir, doc.ID+ext)
		if _, err := os.Stat(path); err == nil {
			if ext == ".pdf" || ext == "" {
				w.Header().Set("Content-Type", "application/pdf")
			} else {
				w.Header().Set("Content-Type", "text/plain")
			}
			// Set filename so Android/browsers handle it properly
			filename := strings.ReplaceAll(doc.Title, " ", "-") + ext
			if ext == "" {
				filename += ".pdf"
			}
			w.Header().Set("Content-Disposition", fmt.Sprintf(`inline; filename="%s"`, filename))
			http.ServeFile(w, r, path)
			return
		}
	}
	http.Error(w, "File not found", http.StatusNotFound)
}

func reindexHandler(w http.ResponseWriter, r *http.Request) {
	// DISABLED - this was destructive (wiped all docs without repopulating)
	// Old behavior cleared all docs then re-indexed markdown files (which we don't use anymore)
	// TODO: Implement safe reprocessing that doesn't delete existing docs
	log.Printf("Reindex endpoint called but disabled (would wipe all data)")
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]string{"status": "reindexed"})
}