Initial orientator

.gitignore

@@ -0,0 +1,3 @@
+.DS_Store
+.gocache/
+.gomodcache/

cmd/orientator/main.go

@@ -0,0 +1,47 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"orientator/internal/server"
+)
+
+func main() {
+	addr := flag.String("addr", envOr("ADDR", ":8080"), "listen address")
+	flag.Parse()
+
+	srv := &http.Server{
+		Addr:           *addr,
+		Handler:        server.New().Handler(),
+		ReadTimeout:    15 * time.Minute,
+		WriteTimeout:   15 * time.Minute,
+		MaxHeaderBytes: 1 << 20,
+	}
+
+	go func() {
+		log.Printf("orientator listening on %s", *addr)
+		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			log.Fatal(err)
+		}
+	}()
+
+	sig := make(chan os.Signal, 1)
+	signal.Notify(sig, syscall.SIGINT, syscall.SIGTERM)
+	<-sig
+	fmt.Println("\nshutting down")
+	_ = srv.Close()
+}
+
+func envOr(k, def string) string {
+	if v := os.Getenv(k); v != "" {
+		return v
+	}
+	return def
+}

cmd/testfixture/main.go

@@ -0,0 +1,41 @@
+// testfixture renders page 1 of a PDF as upright PNG and as a 90°-rotated PNG.
+package main
+
+import (
+	"fmt"
+	"image"
+	"image/png"
+	"os"
+
+	"github.com/gen2brain/go-fitz"
+	"orientator/internal/pipeline"
+)
+
+func main() {
+	if len(os.Args) < 4 {
+		fmt.Println("usage: testfixture <in.pdf> <upright.png> <rotated90.png>")
+		os.Exit(2)
+	}
+	doc, err := fitz.New(os.Args[1])
+	must(err)
+	defer doc.Close()
+	img, err := doc.ImageDPI(0, 150)
+	must(err)
+	writePNG(os.Args[2], img)
+	writePNG(os.Args[3], pipeline.RotateImage(img, 90))
+	fmt.Println("ok")
+}
+
+func writePNG(path string, img image.Image) {
+	f, err := os.Create(path)
+	must(err)
+	defer f.Close()
+	must(png.Encode(f, img))
+}
+
+func must(err error) {
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}

go.mod

@@ -0,0 +1,36 @@
+module orientator
+
+go 1.25.0
+
+require (
+	github.com/gen2brain/go-fitz v1.24.15
+	github.com/pdfcpu/pdfcpu v0.12.0
+	github.com/yalue/onnxruntime_go v1.13.0
+	golang.org/x/image v0.39.0
+)
+
+require (
+	github.com/andybalholm/brotli v1.2.1 // indirect
+	github.com/bodgit/plumbing v1.3.0 // indirect
+	github.com/bodgit/sevenzip v1.6.2 // indirect
+	github.com/bodgit/windows v1.0.1 // indirect
+	github.com/clipperhouse/uax29/v2 v2.7.0 // indirect
+	github.com/ebitengine/purego v0.8.4 // indirect
+	github.com/hashicorp/golang-lru/v2 v2.0.7 // indirect
+	github.com/hhrutter/lzw v1.0.0 // indirect
+	github.com/hhrutter/pkcs7 v0.2.2 // indirect
+	github.com/hhrutter/tiff v1.0.3 // indirect
+	github.com/jupiterrider/ffi v0.5.0 // indirect
+	github.com/klauspost/compress v1.18.5 // indirect
+	github.com/mattn/go-runewidth v0.0.23 // indirect
+	github.com/nwaples/rardecode/v2 v2.2.2 // indirect
+	github.com/pierrec/lz4/v4 v4.1.26 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/spf13/afero v1.15.0 // indirect
+	github.com/ulikunitz/xz v0.5.15 // indirect
+	go4.org v0.0.0-20260112195520-a5071408f32f // indirect
+	golang.org/x/crypto v0.50.0 // indirect
+	golang.org/x/sys v0.43.0 // indirect
+	golang.org/x/text v0.36.0 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
+)

go.sum

@@ -0,0 +1,67 @@
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+github.com/bodgit/plumbing v1.3.0 h1:pf9Itz1JOQgn7vEOE7v7nlEfBykYqvUYioC61TwWCFU=
+github.com/bodgit/plumbing v1.3.0/go.mod h1:JOTb4XiRu5xfnmdnDJo6GmSbSbtSyufrsyZFByMtKEs=
+github.com/bodgit/sevenzip v1.6.2 h1:6/0mwj5KaRXpuf9iSiE+VpG7VpzFJ8D60P53VjxRv34=
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+github.com/bodgit/windows v1.0.1 h1:tF7K6KOluPYygXa3Z2594zxlkbKPAOvqr97etrGNIz4=
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internal/detector/assets/README.txt

@@ -0,0 +1,2 @@
+Place dedoc_orientation.onnx here.
+ONNX runtime shared libs go in onnxruntime/<goos>-<goarch>/.

internal/detector/assets_darwin_arm64.go

@@ -0,0 +1,10 @@
+//go:build darwin && arm64
+
+package detector
+
+import _ "embed"
+
+//go:embed assets/onnxruntime/darwin-arm64/libonnxruntime.dylib
+var runtimeLibBytes []byte
+
+const runtimeLibFileName = "libonnxruntime.dylib"

internal/detector/assets_linux_amd64.go

@@ -0,0 +1,10 @@
+//go:build linux && amd64
+
+package detector
+
+import _ "embed"
+
+//go:embed assets/onnxruntime/linux-amd64/libonnxruntime.so
+var runtimeLibBytes []byte
+
+const runtimeLibFileName = "libonnxruntime.so"

internal/detector/detector.go

@@ -0,0 +1,181 @@
+package detector
+
+import (
+	_ "embed"
+	"fmt"
+	"image"
+	"math"
+	"os"
+	"path/filepath"
+	"runtime"
+	"sync"
+
+	ort "github.com/yalue/onnxruntime_go"
+)
+
+// Angles map to model's [2:6] logits in the same order as the Python reference:
+// indices [0,1,2,3] -> degrees [0, 270, 180, 90].
+var dedocMap = [4]int{0, 270, 180, 90}
+
+//go:embed assets/dedoc_orientation.onnx
+var modelBytes []byte
+
+type Detector struct {
+	session *ort.AdvancedSession
+	input   *ort.Tensor[float32]
+	output  *ort.Tensor[float32]
+	mu      sync.Mutex // ONNX session is not goroutine-safe under concurrent Run
+}
+
+var (
+	once     sync.Once
+	instance *Detector
+	initErr  error
+)
+
+// Get returns the lazily-initialized singleton detector.
+func Get() (*Detector, error) {
+	once.Do(func() {
+		instance, initErr = newDetector()
+	})
+	return instance, initErr
+}
+
+func newDetector() (*Detector, error) {
+	libPath, err := extractRuntimeLib()
+	if err != nil {
+		return nil, fmt.Errorf("extract runtime: %w", err)
+	}
+	ort.SetSharedLibraryPath(libPath)
+	if err := ort.InitializeEnvironment(); err != nil {
+		return nil, fmt.Errorf("init ort env: %w", err)
+	}
+
+	modelPath, err := extractModel()
+	if err != nil {
+		return nil, fmt.Errorf("extract model: %w", err)
+	}
+
+	inputs, outputs, err := ort.GetInputOutputInfo(modelPath)
+	if err != nil {
+		return nil, fmt.Errorf("inspect model: %w", err)
+	}
+	if len(inputs) == 0 || len(outputs) == 0 {
+		return nil, fmt.Errorf("model has no inputs/outputs")
+	}
+
+	inShape := ort.NewShape(1, 3, ImgSize, ImgSize)
+	inTensor, err := ort.NewEmptyTensor[float32](inShape)
+	if err != nil {
+		return nil, err
+	}
+	outShape := ort.NewShape(1, 6)
+	outTensor, err := ort.NewEmptyTensor[float32](outShape)
+	if err != nil {
+		return nil, err
+	}
+
+	opts, err := ort.NewSessionOptions()
+	if err != nil {
+		return nil, err
+	}
+	defer opts.Destroy()
+	_ = opts.SetIntraOpNumThreads(runtime.NumCPU())
+
+	sess, err := ort.NewAdvancedSession(
+		modelPath,
+		[]string{inputs[0].Name},
+		[]string{outputs[0].Name},
+		[]ort.ArbitraryTensor{inTensor},
+		[]ort.ArbitraryTensor{outTensor},
+		opts,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("create session: %w", err)
+	}
+
+	return &Detector{
+		session: sess,
+		input:   inTensor,
+		output:  outTensor,
+	}, nil
+}
+
+// Predict returns the rotation needed to right the image and the confidence.
+// Output angle ∈ {0, 90, 180, 270}; meaning matches the Python reference.
+func (d *Detector) Predict(img image.Image) (angle int, confidence float64, err error) {
+	if img == nil {
+		return 0, 0, fmt.Errorf("nil image")
+	}
+	data := Preprocess(img)
+
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	dst := d.input.GetData()
+	copy(dst, data)
+
+	if err := d.session.Run(); err != nil {
+		return 0, 0, fmt.Errorf("ort run: %w", err)
+	}
+	logits := d.output.GetData() // shape [1,6]
+	// Use only orientation logits at index [2:6].
+	probs := softmax4(logits[2:6])
+	idx := 0
+	best := probs[0]
+	for i := 1; i < 4; i++ {
+		if probs[i] > best {
+			best = probs[i]
+			idx = i
+		}
+	}
+	return dedocMap[idx], float64(best), nil
+}
+
+func softmax4(x []float32) [4]float32 {
+	var max float32 = x[0]
+	for i := 1; i < 4; i++ {
+		if x[i] > max {
+			max = x[i]
+		}
+	}
+	var sum float32
+	var e [4]float32
+	for i := 0; i < 4; i++ {
+		e[i] = float32(math.Exp(float64(x[i] - max)))
+		sum += e[i]
+	}
+	for i := 0; i < 4; i++ {
+		e[i] /= sum
+	}
+	return e
+}
+
+func extractRuntimeLib() (string, error) {
+	return materialize("runtime", runtimeLibFileName, runtimeLibBytes)
+}
+
+func extractModel() (string, error) {
+	return materialize("model", "dedoc_orientation.onnx", modelBytes)
+}
+
+// materialize writes embedded bytes to the user cache dir, reusing the existing
+// file if its size already matches.
+func materialize(subdir, name string, data []byte) (string, error) {
+	cacheDir, err := os.UserCacheDir()
+	if err != nil {
+		cacheDir = os.TempDir()
+	}
+	dir := filepath.Join(cacheDir, "orientator", subdir, fmt.Sprintf("%s-%s", runtime.GOOS, runtime.GOARCH))
+	if err := os.MkdirAll(dir, 0o755); err != nil {
+		return "", err
+	}
+	out := filepath.Join(dir, name)
+	if st, err := os.Stat(out); err == nil && int(st.Size()) == len(data) {
+		return out, nil
+	}
+	if err := os.WriteFile(out, data, 0o644); err != nil {
+		return "", err
+	}
+	return out, nil
+}

internal/detector/preprocess.go

@@ -0,0 +1,53 @@
+package detector
+
+import (
+	"image"
+	"image/color"
+	stddraw "image/draw"
+
+	xdraw "golang.org/x/image/draw"
+)
+
+const ImgSize = 1200
+
+// Preprocess implements the Python reference exactly:
+// 1. resize keeping aspect ratio to fit in 1200x1200 (Lanczos-equivalent CatmullRom)
+// 2. paste onto white 1200x1200 canvas at (0,0)
+// 3. normalize: (x/255 - 0.5) / 0.5
+// 4. HWC -> CHW with batch dim -> [1, 3, 1200, 1200]
+func Preprocess(img image.Image) []float32 {
+	bounds := img.Bounds()
+	w, h := bounds.Dx(), bounds.Dy()
+
+	scale := float64(ImgSize) / float64(w)
+	if s := float64(ImgSize) / float64(h); s < scale {
+		scale = s
+	}
+	newW := int(float64(w) * scale)
+	newH := int(float64(h) * scale)
+	if newW < 1 {
+		newW = 1
+	}
+	if newH < 1 {
+		newH = 1
+	}
+
+	canvas := image.NewRGBA(image.Rect(0, 0, ImgSize, ImgSize))
+	stddraw.Draw(canvas, canvas.Bounds(), &image.Uniform{C: color.RGBA{255, 255, 255, 255}}, image.Point{}, stddraw.Src)
+	xdraw.CatmullRom.Scale(canvas, image.Rect(0, 0, newW, newH), img, bounds, xdraw.Over, nil)
+
+	out := make([]float32, 3*ImgSize*ImgSize)
+	plane := ImgSize * ImgSize
+	pix := canvas.Pix
+	for y := 0; y < ImgSize; y++ {
+		row := y * canvas.Stride
+		base := y * ImgSize
+		for x := 0; x < ImgSize; x++ {
+			i := row + x*4
+			out[base+x] = float32(pix[i+0])/127.5 - 1
+			out[plane+base+x] = float32(pix[i+1])/127.5 - 1
+			out[2*plane+base+x] = float32(pix[i+2])/127.5 - 1
+		}
+	}
+	return out
+}

internal/extract/archive.go

@@ -0,0 +1,160 @@
+// Package extract iterates over the contents of common archive formats
+// (zip, tar, tar.gz, 7z, rar) without extracting to disk.
+package extract
+
+import (
+	"archive/tar"
+	"archive/zip"
+	"bytes"
+	"compress/gzip"
+	"errors"
+	"fmt"
+	"io"
+	"path/filepath"
+	"strings"
+
+	"github.com/bodgit/sevenzip"
+	"github.com/nwaples/rardecode/v2"
+)
+
+type Entry struct {
+	Name string
+	Data []byte
+}
+
+type WalkFn func(Entry) error
+
+// Walk dispatches by extension and calls fn for each file entry.
+func Walk(name string, data []byte, fn WalkFn) error {
+	ext := strings.ToLower(filepath.Ext(name))
+	switch ext {
+	case ".zip":
+		return walkZip(data, fn)
+	case ".tar":
+		return walkTar(bytes.NewReader(data), fn)
+	case ".gz", ".tgz":
+		return walkTarGz(data, fn)
+	case ".7z":
+		return walk7z(data, fn)
+	case ".rar":
+		return walkRar(data, fn)
+	}
+	return fmt.Errorf("unsupported archive: %s", ext)
+}
+
+// IsArchive reports whether name has an extension we know how to extract.
+func IsArchive(name string) bool {
+	switch strings.ToLower(filepath.Ext(name)) {
+	case ".zip", ".tar", ".gz", ".tgz", ".7z", ".rar":
+		return true
+	}
+	return false
+}
+
+func walkZip(data []byte, fn WalkFn) error {
+	r, err := zip.NewReader(bytes.NewReader(data), int64(len(data)))
+	if err != nil {
+		return err
+	}
+	for _, f := range r.File {
+		if f.FileInfo().IsDir() {
+			continue
+		}
+		rc, err := f.Open()
+		if err != nil {
+			return err
+		}
+		buf, err := io.ReadAll(rc)
+		rc.Close()
+		if err != nil {
+			return err
+		}
+		if err := fn(Entry{Name: f.Name, Data: buf}); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func walkTar(r io.Reader, fn WalkFn) error {
+	tr := tar.NewReader(r)
+	for {
+		hdr, err := tr.Next()
+		if errors.Is(err, io.EOF) {
+			return nil
+		}
+		if err != nil {
+			return err
+		}
+		if hdr.Typeflag != tar.TypeReg {
+			continue
+		}
+		buf, err := io.ReadAll(tr)
+		if err != nil {
+			return err
+		}
+		if err := fn(Entry{Name: hdr.Name, Data: buf}); err != nil {
+			return err
+		}
+	}
+}
+
+func walkTarGz(data []byte, fn WalkFn) error {
+	gz, err := gzip.NewReader(bytes.NewReader(data))
+	if err != nil {
+		return err
+	}
+	defer gz.Close()
+	return walkTar(gz, fn)
+}
+
+func walk7z(data []byte, fn WalkFn) error {
+	r, err := sevenzip.NewReader(bytes.NewReader(data), int64(len(data)))
+	if err != nil {
+		return err
+	}
+	for _, f := range r.File {
+		if f.FileInfo().IsDir() {
+			continue
+		}
+		rc, err := f.Open()
+		if err != nil {
+			return err
+		}
+		buf, err := io.ReadAll(rc)
+		rc.Close()
+		if err != nil {
+			return err
+		}
+		if err := fn(Entry{Name: f.Name, Data: buf}); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func walkRar(data []byte, fn WalkFn) error {
+	r, err := rardecode.NewReader(bytes.NewReader(data))
+	if err != nil {
+		return err
+	}
+	for {
+		hdr, err := r.Next()
+		if errors.Is(err, io.EOF) {
+			return nil
+		}
+		if err != nil {
+			return err
+		}
+		if hdr.IsDir {
+			continue
+		}
+		buf, err := io.ReadAll(r)
+		if err != nil {
+			return err
+		}
+		if err := fn(Entry{Name: hdr.Name, Data: buf}); err != nil {
+			return err
+		}
+	}
+}

internal/pipeline/imgrot.go

@@ -0,0 +1,80 @@
+package pipeline
+
+import (
+	"bytes"
+	"fmt"
+	"image"
+	"image/jpeg"
+	"image/png"
+	"strings"
+
+	"golang.org/x/image/tiff"
+	_ "golang.org/x/image/webp" // decode-only; we re-encode webp as png
+)
+
+// RotateImage rotates src clockwise by angle (must be 0/90/180/270).
+func RotateImage(src image.Image, angle int) image.Image {
+	angle = ((angle % 360) + 360) % 360
+	if angle == 0 {
+		return src
+	}
+	b := src.Bounds()
+	w, h := b.Dx(), b.Dy()
+	switch angle {
+	case 180:
+		dst := image.NewRGBA(image.Rect(0, 0, w, h))
+		for y := 0; y < h; y++ {
+			for x := 0; x < w; x++ {
+				dst.Set(w-1-x, h-1-y, src.At(b.Min.X+x, b.Min.Y+y))
+			}
+		}
+		return dst
+	case 90:
+		dst := image.NewRGBA(image.Rect(0, 0, h, w))
+		for y := 0; y < h; y++ {
+			for x := 0; x < w; x++ {
+				dst.Set(h-1-y, x, src.At(b.Min.X+x, b.Min.Y+y))
+			}
+		}
+		return dst
+	case 270:
+		dst := image.NewRGBA(image.Rect(0, 0, h, w))
+		for y := 0; y < h; y++ {
+			for x := 0; x < w; x++ {
+				dst.Set(y, w-1-x, src.At(b.Min.X+x, b.Min.Y+y))
+			}
+		}
+		return dst
+	}
+	return src
+}
+
+// EncodeImage re-encodes img using format hint from the original filename / detected format.
+// Falls back to PNG when format is not directly writable.
+func EncodeImage(img image.Image, format string) ([]byte, string, error) {
+	var buf bytes.Buffer
+	switch strings.ToLower(format) {
+	case "jpeg", "jpg":
+		if err := jpeg.Encode(&buf, img, &jpeg.Options{Quality: 92}); err != nil {
+			return nil, "", err
+		}
+		return buf.Bytes(), "jpg", nil
+	case "tiff", "tif":
+		if err := tiff.Encode(&buf, img, &tiff.Options{Compression: tiff.Deflate}); err != nil {
+			return nil, "", err
+		}
+		return buf.Bytes(), "tiff", nil
+	case "png", "":
+		if err := png.Encode(&buf, img); err != nil {
+			return nil, "", err
+		}
+		return buf.Bytes(), "png", nil
+	case "webp":
+		// Re-encode to PNG (no webp encoder in stdlib/x/image).
+		if err := png.Encode(&buf, img); err != nil {
+			return nil, "", err
+		}
+		return buf.Bytes(), "png", nil
+	}
+	return nil, "", fmt.Errorf("unsupported format: %s", format)
+}

internal/pipeline/pipeline.go

@@ -0,0 +1,198 @@
+// Package pipeline orchestrates orientation detection and rotation across
+// images, PDFs, and archives.
+package pipeline
+
+import (
+	"archive/zip"
+	"bytes"
+	"fmt"
+	"image"
+	_ "image/jpeg"
+	_ "image/png"
+	"io"
+	"path/filepath"
+	"strings"
+	"sync"
+
+	_ "golang.org/x/image/tiff"
+	_ "golang.org/x/image/webp"
+
+	"orientator/internal/detector"
+	"orientator/internal/extract"
+	"orientator/internal/rasterize"
+)
+
+// PageReport describes what happened to a single page or image.
+type PageReport struct {
+	File       string  `json:"file"`
+	Page       int     `json:"page,omitempty"` // 0 for plain images
+	Angle      int     `json:"angle"`
+	Confidence float64 `json:"confidence"`
+}
+
+// Result holds the rewritten output and a per-page report.
+type Result struct {
+	OutputName  string
+	OutputBytes []byte
+	Reports     []PageReport
+}
+
+// Process processes a single uploaded file and returns the corrected output.
+// For archives the output is a zip of all corrected entries.
+func Process(name string, data []byte) (*Result, error) {
+	det, err := detector.Get()
+	if err != nil {
+		return nil, fmt.Errorf("detector init: %w", err)
+	}
+
+	if extract.IsArchive(name) {
+		return processArchive(det, name, data)
+	}
+	return processSingle(det, name, data)
+}
+
+func processSingle(det *detector.Detector, name string, data []byte) (*Result, error) {
+	ext := strings.ToLower(filepath.Ext(name))
+	switch ext {
+	case ".pdf":
+		out, reports, err := processPDF(det, name, data)
+		if err != nil {
+			return nil, err
+		}
+		return &Result{OutputName: name, OutputBytes: out, Reports: reports}, nil
+	case ".jpg", ".jpeg", ".png", ".tif", ".tiff", ".webp", ".bmp":
+		out, outName, report, err := processImage(det, name, data)
+		if err != nil {
+			return nil, err
+		}
+		return &Result{OutputName: outName, OutputBytes: out, Reports: []PageReport{report}}, nil
+	}
+	return nil, fmt.Errorf("unsupported file type: %s", ext)
+}
+
+func processImage(det *detector.Detector, name string, data []byte) ([]byte, string, PageReport, error) {
+	img, format, err := image.Decode(bytes.NewReader(data))
+	if err != nil {
+		return nil, "", PageReport{}, fmt.Errorf("decode %s: %w", name, err)
+	}
+	angle, conf, err := det.Predict(img)
+	if err != nil {
+		return nil, "", PageReport{}, err
+	}
+	rotated := RotateImage(img, angle)
+	out, ext, err := EncodeImage(rotated, format)
+	if err != nil {
+		return nil, "", PageReport{}, err
+	}
+	outName := replaceExt(name, "."+ext)
+	return out, outName, PageReport{File: name, Angle: angle, Confidence: conf}, nil
+}
+
+func processPDF(det *detector.Detector, name string, data []byte) ([]byte, []PageReport, error) {
+	pdf, err := rasterize.Open(data)
+	if err != nil {
+		return nil, nil, err
+	}
+	defer pdf.Close()
+
+	n := pdf.NumPages()
+	angles := make([]int, n)
+	reports := make([]PageReport, 0, n)
+	for i := 0; i < n; i++ {
+		img, err := pdf.RenderPage(i)
+		if err != nil {
+			return nil, nil, err
+		}
+		angle, conf, err := det.Predict(img)
+		if err != nil {
+			return nil, nil, err
+		}
+		angles[i] = angle
+		reports = append(reports, PageReport{File: name, Page: i + 1, Angle: angle, Confidence: conf})
+	}
+	out, err := rasterize.RotatePDFPages(data, angles)
+	if err != nil {
+		return nil, nil, err
+	}
+	return out, reports, nil
+}
+
+func processArchive(det *detector.Detector, name string, data []byte) (*Result, error) {
+	var (
+		mu      sync.Mutex
+		buf     bytes.Buffer
+		zw      = zip.NewWriter(&buf)
+		reports []PageReport
+	)
+
+	err := extract.Walk(name, data, func(e extract.Entry) error {
+		// Recurse into nested archives.
+		if extract.IsArchive(e.Name) {
+			sub, err := Process(e.Name, e.Data)
+			if err != nil {
+				return writeZipFailure(zw, e.Name, err)
+			}
+			mu.Lock()
+			reports = append(reports, sub.Reports...)
+			mu.Unlock()
+			return writeZipEntry(zw, sub.OutputName, sub.OutputBytes)
+		}
+
+		ext := strings.ToLower(filepath.Ext(e.Name))
+		switch ext {
+		case ".pdf":
+			out, rs, err := processPDF(det, e.Name, e.Data)
+			if err != nil {
+				return writeZipFailure(zw, e.Name, err)
+			}
+			mu.Lock()
+			reports = append(reports, rs...)
+			mu.Unlock()
+			return writeZipEntry(zw, e.Name, out)
+		case ".jpg", ".jpeg", ".png", ".tif", ".tiff", ".webp", ".bmp":
+			out, outName, r, err := processImage(det, e.Name, e.Data)
+			if err != nil {
+				return writeZipFailure(zw, e.Name, err)
+			}
+			mu.Lock()
+			reports = append(reports, r)
+			mu.Unlock()
+			return writeZipEntry(zw, outName, out)
+		default:
+			// Pass-through any non-document files.
+			return writeZipEntry(zw, e.Name, e.Data)
+		}
+	})
+	if err != nil {
+		return nil, err
+	}
+	if err := zw.Close(); err != nil {
+		return nil, err
+	}
+
+	outName := replaceExt(name, ".zip")
+	return &Result{OutputName: outName, OutputBytes: buf.Bytes(), Reports: reports}, nil
+}
+
+func writeZipEntry(zw *zip.Writer, name string, data []byte) error {
+	w, err := zw.Create(name)
+	if err != nil {
+		return err
+	}
+	_, err = io.Copy(w, bytes.NewReader(data))
+	return err
+}
+
+func writeZipFailure(zw *zip.Writer, name string, cause error) error {
+	w, err := zw.Create(name + ".error.txt")
+	if err != nil {
+		return err
+	}
+	_, _ = w.Write([]byte(cause.Error()))
+	return nil
+}
+
+func replaceExt(name, newExt string) string {
+	old := filepath.Ext(name)
+	return strings.TrimSuffix(name, old) + newExt
+}

internal/rasterize/pdf.go

@@ -0,0 +1,51 @@
+// Package rasterize converts PDF pages to in-memory images using MuPDF.
+package rasterize
+
+import (
+	"fmt"
+	"image"
+
+	"github.com/gen2brain/go-fitz"
+)
+
+// DPI used when rasterizing pages for the orientation classifier.
+// 150 mirrors the Ghostscript -r150 flag used in the original Python pipeline.
+const DPI = 150
+
+type Page struct {
+	Index int
+	Img   image.Image
+}
+
+// PDF wraps an open MuPDF document.
+type PDF struct {
+	doc *fitz.Document
+}
+
+func Open(data []byte) (*PDF, error) {
+	doc, err := fitz.NewFromMemory(data)
+	if err != nil {
+		return nil, fmt.Errorf("fitz open: %w", err)
+	}
+	return &PDF{doc: doc}, nil
+}
+
+func (p *PDF) Close() error {
+	if p == nil || p.doc == nil {
+		return nil
+	}
+	return p.doc.Close()
+}
+
+func (p *PDF) NumPages() int {
+	return p.doc.NumPage()
+}
+
+// RenderPage rasterizes a single page at the configured DPI.
+func (p *PDF) RenderPage(idx int) (image.Image, error) {
+	img, err := p.doc.ImageDPI(idx, DPI)
+	if err != nil {
+		return nil, fmt.Errorf("render page %d: %w", idx, err)
+	}
+	return img, nil
+}

internal/rasterize/rotate.go

@@ -0,0 +1,51 @@
+package rasterize
+
+import (
+	"bytes"
+	"fmt"
+
+	"github.com/pdfcpu/pdfcpu/pkg/api"
+	"github.com/pdfcpu/pdfcpu/pkg/pdfcpu/model"
+)
+
+// RotatePDFPages applies clockwise rotations (degrees, multiples of 90) to each page.
+// pageRotations is 1-indexed slice aligned with input pages: pageRotations[0] = page 1.
+func RotatePDFPages(in []byte, pageRotations []int) ([]byte, error) {
+	conf := model.NewDefaultConfiguration()
+	conf.ValidationMode = model.ValidationRelaxed
+
+	// pdfcpu's Rotate API takes a single rotation and a page selection. We group
+	// pages by rotation value to minimize passes.
+	groups := map[int][]int{}
+	for i, r := range pageRotations {
+		r = ((r % 360) + 360) % 360
+		if r == 0 {
+			continue
+		}
+		groups[r] = append(groups[r], i+1)
+	}
+	if len(groups) == 0 {
+		out := make([]byte, len(in))
+		copy(out, in)
+		return out, nil
+	}
+
+	current := bytes.NewReader(in)
+	var buf bytes.Buffer
+	for rot, pages := range groups {
+		buf.Reset()
+		selectedPages := make([]string, len(pages))
+		for i, p := range pages {
+			selectedPages[i] = fmt.Sprintf("%d", p)
+		}
+		if err := api.Rotate(current, &buf, rot, selectedPages, conf); err != nil {
+			return nil, fmt.Errorf("rotate %d°: %w", rot, err)
+		}
+		current = bytes.NewReader(append([]byte(nil), buf.Bytes()...))
+	}
+	out := make([]byte, current.Size())
+	if _, err := current.ReadAt(out, 0); err != nil {
+		return nil, err
+	}
+	return out, nil
+}

internal/server/combined.go

@@ -0,0 +1,52 @@
+package server
+
+import (
+	"archive/zip"
+	"bytes"
+	"io"
+
+	"orientator/internal/pipeline"
+)
+
+type combinedZip struct {
+	results []*pipeline.Result
+	errors  map[string]error
+}
+
+func (c *combinedZip) add(r *pipeline.Result) {
+	c.results = append(c.results, r)
+}
+
+func (c *combinedZip) addError(name string, err error) {
+	if c.errors == nil {
+		c.errors = map[string]error{}
+	}
+	c.errors[name] = err
+}
+
+func (c *combinedZip) finalize() ([]byte, []pipeline.PageReport, error) {
+	var buf bytes.Buffer
+	zw := zip.NewWriter(&buf)
+	var allReports []pipeline.PageReport
+	for _, r := range c.results {
+		w, err := zw.Create(r.OutputName)
+		if err != nil {
+			return nil, nil, err
+		}
+		if _, err := io.Copy(w, bytes.NewReader(r.OutputBytes)); err != nil {
+			return nil, nil, err
+		}
+		allReports = append(allReports, r.Reports...)
+	}
+	for name, err := range c.errors {
+		w, e := zw.Create(name + ".error.txt")
+		if e != nil {
+			return nil, nil, e
+		}
+		_, _ = w.Write([]byte(err.Error()))
+	}
+	if err := zw.Close(); err != nil {
+		return nil, nil, err
+	}
+	return buf.Bytes(), allReports, nil
+}

internal/server/server.go

@@ -0,0 +1,164 @@
+package server
+
+import (
+	"embed"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/fs"
+	"net/http"
+	"net/url"
+	"path/filepath"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"orientator/internal/pipeline"
+)
+
+//go:embed all:web
+var webFS embed.FS
+
+type Server struct {
+	mux *http.ServeMux
+}
+
+func New() *Server {
+	s := &Server{mux: http.NewServeMux()}
+	sub, _ := fs.Sub(webFS, "web")
+	s.mux.Handle("/", http.FileServer(http.FS(sub)))
+	s.mux.HandleFunc("/api/process", s.handleProcess)
+	s.mux.HandleFunc("/api/health", func(w http.ResponseWriter, r *http.Request) {
+		w.Write([]byte("ok"))
+	})
+	return s
+}
+
+func (s *Server) Handler() http.Handler { return s.mux }
+
+const maxUploadBytes = 2 << 30 // 2 GiB
+
+func (s *Server) handleProcess(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+	r.Body = http.MaxBytesReader(w, r.Body, maxUploadBytes)
+	if err := r.ParseMultipartForm(64 << 20); err != nil {
+		writeErr(w, http.StatusBadRequest, err)
+		return
+	}
+	files := r.MultipartForm.File["files"]
+	if len(files) == 0 {
+		writeErr(w, http.StatusBadRequest, errors.New("no files"))
+		return
+	}
+
+	if len(files) == 1 {
+		fh := files[0]
+		f, err := fh.Open()
+		if err != nil {
+			writeErr(w, http.StatusBadRequest, err)
+			return
+		}
+		data, err := io.ReadAll(f)
+		f.Close()
+		if err != nil {
+			writeErr(w, http.StatusBadRequest, err)
+			return
+		}
+		res, err := pipeline.Process(fh.Filename, data)
+		if err != nil {
+			writeErr(w, http.StatusUnprocessableEntity, err)
+			return
+		}
+		writeFile(w, res.OutputName, res.OutputBytes, res.Reports)
+		return
+	}
+
+	// Multiple files: synthesize a tar/zip wrapping name and pack outputs.
+	combined := &combinedZip{}
+	for _, fh := range files {
+		f, err := fh.Open()
+		if err != nil {
+			writeErr(w, http.StatusBadRequest, err)
+			return
+		}
+		data, err := io.ReadAll(f)
+		f.Close()
+		if err != nil {
+			writeErr(w, http.StatusBadRequest, err)
+			return
+		}
+		res, err := pipeline.Process(fh.Filename, data)
+		if err != nil {
+			combined.addError(fh.Filename, err)
+			continue
+		}
+		combined.add(res)
+	}
+	out, reports, err := combined.finalize()
+	if err != nil {
+		writeErr(w, http.StatusInternalServerError, err)
+		return
+	}
+	writeFile(w, "orientator-output.zip", out, reports)
+}
+
+func writeErr(w http.ResponseWriter, code int, err error) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(code)
+	_ = json.NewEncoder(w).Encode(map[string]string{"error": err.Error()})
+}
+
+func writeFile(w http.ResponseWriter, name string, data []byte, reports []pipeline.PageReport) {
+	rep, _ := json.Marshal(reports)
+	w.Header().Set("Content-Type", contentTypeFor(name))
+	w.Header().Set("Content-Disposition", contentDisposition(name))
+	w.Header().Set("X-Orientator-Reports", url.QueryEscape(string(rep)))
+	w.Header().Set("Content-Length", fmt.Sprintf("%d", len(data)))
+	w.Write(data)
+}
+
+func contentDisposition(name string) string {
+	base := filepath.Base(name)
+	return fmt.Sprintf(
+		"attachment; filename=%q; filename*=UTF-8''%s",
+		asciiFilename(base),
+		url.PathEscape(base),
+	)
+}
+
+func asciiFilename(name string) string {
+	var b strings.Builder
+	b.Grow(len(name))
+	for _, r := range name {
+		switch {
+		case r < utf8.RuneSelf && (unicode.IsLetter(r) || unicode.IsDigit(r) || r == '.' || r == '-' || r == '_'):
+			b.WriteRune(r)
+		case unicode.IsSpace(r):
+			b.WriteByte('_')
+		}
+	}
+	if b.Len() == 0 {
+		return "output"
+	}
+	return b.String()
+}
+
+func contentTypeFor(name string) string {
+	switch strings.ToLower(filepath.Ext(name)) {
+	case ".pdf":
+		return "application/pdf"
+	case ".zip":
+		return "application/zip"
+	case ".png":
+		return "image/png"
+	case ".jpg", ".jpeg":
+		return "image/jpeg"
+	case ".tif", ".tiff":
+		return "image/tiff"
+	}
+	return "application/octet-stream"
+}

internal/server/web/app.js

@@ -0,0 +1,353 @@
+const drop = document.getElementById('drop');
+const fileInput = document.getElementById('file');
+const pickBtn = document.getElementById('pick');
+const queue = document.getElementById('queue');
+const processAllBtn = document.getElementById('process-all');
+const clearBtn = document.getElementById('clear');
+const summaryTitle = document.getElementById('summary-title');
+const summaryMeta = document.getElementById('summary-meta');
+
+const jobs = [];
+let nextId = 1;
+let activeXhr = null;
+
+['dragenter', 'dragover'].forEach(ev =>
+  drop.addEventListener(ev, e => { e.preventDefault(); drop.classList.add('drag'); })
+);
+['dragleave', 'drop'].forEach(ev =>
+  drop.addEventListener(ev, e => { e.preventDefault(); drop.classList.remove('drag'); })
+);
+drop.addEventListener('drop', e => addFiles(e.dataTransfer.files));
+drop.addEventListener('click', () => fileInput.click());
+drop.addEventListener('keydown', e => {
+  if (e.key === 'Enter' || e.key === ' ') {
+    e.preventDefault();
+    fileInput.click();
+  }
+});
+pickBtn.addEventListener('click', e => { e.stopPropagation(); fileInput.click(); });
+fileInput.addEventListener('change', () => {
+  addFiles(fileInput.files);
+  fileInput.value = '';
+});
+processAllBtn.addEventListener('click', processPending);
+clearBtn.addEventListener('click', clearQueue);
+
+function addFiles(files) {
+  for (const file of files) {
+    jobs.unshift({
+      id: nextId++,
+      file,
+      state: 'ready',
+      status: 'в очереди',
+      progress: 0,
+      reports: [],
+      error: '',
+      download: null,
+      outputName: ''
+    });
+  }
+  render();
+}
+
+function clearQueue() {
+  if (activeXhr) activeXhr.abort();
+  activeXhr = null;
+  for (const job of jobs) {
+    if (job.download) URL.revokeObjectURL(job.download);
+  }
+  jobs.splice(0, jobs.length);
+  render();
+}
+
+function processPending() {
+  const selected = jobs.filter(j => j.state === 'ready' || j.state === 'error');
+  if (!selected.length || activeXhr) return;
+  processJobs(selected);
+}
+
+function retryJob(id) {
+  const job = jobs.find(j => j.id === id);
+  if (!job || activeXhr) return;
+  processJobs([job]);
+}
+
+function removeJob(id) {
+  const idx = jobs.findIndex(j => j.id === id);
+  if (idx < 0 || activeXhr) return;
+  const [job] = jobs.splice(idx, 1);
+  if (job.download) URL.revokeObjectURL(job.download);
+  render();
+}
+
+function processJobs(selected) {
+  selected.forEach(job => {
+    job.state = 'run';
+    job.status = 'загрузка';
+    job.progress = 4;
+    job.error = '';
+    job.reports = [];
+    if (job.download) URL.revokeObjectURL(job.download);
+    job.download = null;
+    job.outputName = '';
+  });
+  render();
+
+  const fd = new FormData();
+  selected.forEach(job => fd.append('files', job.file));
+
+  const xhr = new XMLHttpRequest();
+  activeXhr = xhr;
+  xhr.open('POST', '/api/process');
+  xhr.responseType = 'blob';
+  xhr.upload.onprogress = e => {
+    const pct = e.lengthComputable ? Math.min(70, Math.round(e.loaded / e.total * 70)) : 35;
+    selected.forEach(job => {
+      job.progress = pct;
+      job.status = pct >= 70 ? 'обработка' : 'загрузка';
+    });
+    render();
+  };
+  xhr.onprogress = () => {
+    selected.forEach(job => {
+      job.progress = Math.max(job.progress, 85);
+      job.status = 'получение';
+    });
+    render();
+  };
+  xhr.onload = () => {
+    activeXhr = null;
+    if (xhr.status >= 200 && xhr.status < 300) {
+      handleSuccess(xhr, selected);
+    } else {
+      handleFailure(xhr, selected);
+    }
+    render();
+  };
+  xhr.onerror = () => {
+    activeXhr = null;
+    selected.forEach(job => markError(job, 'Сеть или сервер оборвали запрос'));
+    render();
+  };
+  xhr.onabort = () => {
+    selected.forEach(job => markError(job, 'Обработка отменена'));
+    render();
+  };
+  xhr.send(fd);
+}
+
+function handleSuccess(xhr, selected) {
+  const blob = xhr.response;
+  const cd = xhr.getResponseHeader('Content-Disposition') || '';
+  const outputName = filenameFromContentDisposition(cd) || (selected.length > 1 ? 'orientator-output.zip' : 'output');
+  const reports = parseReports(xhr.getResponseHeader('X-Orientator-Reports'));
+
+  if (selected.length === 1) {
+    const job = selected[0];
+    job.state = 'done';
+    job.status = 'готово';
+    job.progress = 100;
+    job.outputName = outputName;
+    job.download = URL.createObjectURL(blob);
+    job.reports = reports;
+    return;
+  }
+
+  const batchJob = {
+    id: nextId++,
+    file: new File([blob], outputName),
+    kind: 'batch',
+    sourceCount: selected.length,
+    state: 'done',
+    status: 'готов к скачиванию',
+    progress: 100,
+    reports,
+    error: '',
+    download: URL.createObjectURL(blob),
+    outputName
+  };
+  jobs.unshift(batchJob);
+  selected.forEach(job => {
+    const jobReports = reports.filter(r => r.file === job.file.name);
+    job.state = 'done';
+    job.status = jobReports.length ? 'добавлено в архив' : 'см. архив';
+    job.progress = 100;
+    job.reports = jobReports;
+    job.error = jobReports.length ? '' : 'По этому файлу нет отчета. Если формат не поддерживается, в итоговом zip будет файл с ошибкой .error.txt.';
+  });
+}
+
+function handleFailure(xhr, selected) {
+  if (!xhr.response) {
+    selected.forEach(job => markError(job, 'Сервер вернул ошибку без текста'));
+    return;
+  }
+  const reader = new FileReader();
+  reader.onload = () => {
+    let msg = reader.result || 'Ошибка обработки';
+    try {
+      msg = JSON.parse(reader.result).error || msg;
+    } catch {}
+    selected.forEach(job => markError(job, msg));
+    render();
+  };
+  reader.readAsText(xhr.response);
+}
+
+function markError(job, msg) {
+  job.state = 'error';
+  job.status = 'ошибка';
+  job.progress = 100;
+  job.error = msg;
+}
+
+function render() {
+  updateSummary();
+  queue.innerHTML = '';
+  if (!jobs.length) {
+    queue.innerHTML = '<div class="empty">Добавьте документы для обработки.</div>';
+    return;
+  }
+  for (const job of jobs) {
+    queue.appendChild(renderJob(job));
+  }
+}
+
+function renderJob(job) {
+  const item = document.createElement('article');
+  item.className = `item ${job.state}`;
+
+  const main = document.createElement('div');
+  const name = document.createElement('div');
+  name.className = 'name';
+  name.textContent = job.kind === 'batch'
+    ? `Итоговый архив: ${job.outputName || job.file.name}`
+    : (job.outputName || job.file.name);
+  const meta = document.createElement('div');
+  meta.className = 'meta';
+  meta.textContent = job.kind === 'batch'
+    ? `Скачать один zip с результатами по ${job.sourceCount || 0} файл(ам) · ${fmtBytes(job.file.size)}`
+    : [fmtBytes(job.file.size), fileKind(job.file.name)].filter(Boolean).join(' · ');
+  main.append(name, meta);
+
+  const right = document.createElement('div');
+  right.className = 'right';
+  if (job.download) {
+    const a = document.createElement('a');
+    a.href = job.download;
+    a.textContent = 'Скачать';
+    a.download = job.outputName || job.file.name;
+    a.className = 'btn';
+    right.appendChild(a);
+  }
+  if (job.kind !== 'batch' && (job.state === 'ready' || job.state === 'error' || job.state === 'done')) {
+    right.appendChild(button('Обработать заново', 'btn ghost', () => retryJob(job.id), Boolean(activeXhr)));
+  }
+  if (job.state !== 'run') {
+    right.appendChild(button('Убрать', 'icon-btn', () => removeJob(job.id), Boolean(activeXhr), 'x'));
+  }
+  const status = document.createElement('span');
+  status.className = 'status';
+  status.textContent = job.status;
+  right.appendChild(status);
+
+  const bar = document.createElement('div');
+  bar.className = 'bar';
+  const fill = document.createElement('i');
+  fill.style.width = `${job.progress}%`;
+  bar.appendChild(fill);
+
+  item.append(main, right, bar);
+
+  if (job.error) {
+    const err = document.createElement('div');
+    err.className = 'report error-text';
+    err.textContent = job.error;
+    item.appendChild(err);
+  } else if (job.reports.length) {
+    item.appendChild(renderReport(job.reports));
+  }
+  return item;
+}
+
+function renderReport(reports) {
+  const box = document.createElement('div');
+  box.className = 'report';
+  const changed = reports.filter(r => r.angle && r.angle !== 0).length;
+  const avg = reports.reduce((sum, r) => sum + (r.confidence || 0), 0) / reports.length;
+  const files = new Set(reports.map(r => r.file));
+  const head = document.createElement('div');
+  head.className = 'report-head';
+  head.textContent = `${reports.length} стр. · повернуто ${changed} · средняя уверенность ${(avg * 100).toFixed(1)}%`;
+  const list = document.createElement('pre');
+  list.textContent = reports.map(r => {
+    const page = r.page ? `стр. ${r.page}` : 'файл';
+    return `${page}: ${r.angle}° · ${(r.confidence * 100).toFixed(1)}%`;
+  }).map((line, i) => {
+    const r = reports[i];
+    return files.size > 1 ? `${r.file} · ${line}` : line;
+  }).join('\n');
+  box.append(head, list);
+  return box;
+}
+
+function updateSummary() {
+  const total = jobs.length;
+  const ready = jobs.filter(j => j.state === 'ready' || j.state === 'error').length;
+  const done = jobs.filter(j => j.state === 'done').length;
+  const running = jobs.some(j => j.state === 'run');
+  const bytes = jobs.reduce((sum, j) => sum + j.file.size, 0);
+
+  summaryTitle.textContent = total ? `${total} файл(ов) · ${fmtBytes(bytes)}` : 'Файлов нет';
+  summaryMeta.textContent = total ? `${ready} ожидает · ${done} готово` : 'pdf, png, jpg, tiff, webp, bmp, zip, 7z, rar, tar.gz';
+  processAllBtn.disabled = !ready || running;
+  clearBtn.disabled = !total;
+  processAllBtn.textContent = running ? 'Идет обработка' : (ready > 1 ? 'Обработать все в zip' : 'Обработать');
+}
+
+function button(text, className, onClick, disabled, title) {
+  const b = document.createElement('button');
+  b.type = 'button';
+  b.className = className;
+  b.textContent = title || text;
+  b.title = text;
+  b.disabled = disabled;
+  b.addEventListener('click', onClick);
+  return b;
+}
+
+function fmtBytes(n) {
+  if (n < 1024) return n + ' B';
+  if (n < 1024 * 1024) return (n / 1024).toFixed(1) + ' KB';
+  if (n < 1024 * 1024 * 1024) return (n / 1024 / 1024).toFixed(1) + ' MB';
+  return (n / 1024 / 1024 / 1024).toFixed(2) + ' GB';
+}
+
+function fileKind(name) {
+  const lower = name.toLowerCase();
+  if (lower.endsWith('.tar.gz')) return 'tar.gz';
+  const i = lower.lastIndexOf('.');
+  return i >= 0 ? lower.slice(i + 1) : '';
+}
+
+function parseReports(header) {
+  if (!header) return [];
+  try {
+    return JSON.parse(decodeURIComponent(header.replace(/\+/g, ' ')));
+  } catch {
+    return [];
+  }
+}
+
+function filenameFromContentDisposition(cd) {
+  const encoded = cd.match(/filename\*=UTF-8''([^;]+)/i);
+  if (encoded) {
+    try {
+      return decodeURIComponent(encoded[1]);
+    } catch {}
+  }
+  const plain = cd.match(/filename="([^"]+)"|filename=([^;]+)/i);
+  return plain ? (plain[1] || plain[2]).trim() : '';
+}
+
+render();

internal/server/web/index.html

@@ -0,0 +1,51 @@
+<!doctype html>
+<html lang="ru">
+<head>
+  <meta charset="utf-8" />
+  <meta name="viewport" content="width=device-width,initial-scale=1" />
+  <title>Orientator</title>
+  <link rel="stylesheet" href="/style.css" />
+</head>
+<body>
+  <header class="topbar">
+    <div class="brand">
+      <span class="dot"></span>
+      <span class="name">orientator</span>
+    </div>
+    <span class="version">v1</span>
+  </header>
+
+  <main class="container">
+    <section class="workspace">
+      <div class="intro">
+        <h1>Автоповорот документов</h1>
+        <p>PDF, изображения и архивы обрабатываются моделью постранично.</p>
+      </div>
+
+      <section id="drop" class="dropzone" tabindex="0">
+        <input id="file" type="file" multiple hidden />
+        <div class="dz-inner">
+          <div class="dz-icon"></div>
+          <div class="dz-title">Перетащите файлы сюда</div>
+          <div class="dz-sub">или <button type="button" id="pick">выберите</button></div>
+        </div>
+      </section>
+
+      <section class="controls" aria-label="Очередь обработки">
+        <div class="summary">
+          <strong id="summary-title">Файлов нет</strong>
+          <span id="summary-meta">pdf, png, jpg, tiff, webp, bmp, zip, 7z, rar, tar.gz</span>
+        </div>
+        <div class="actions">
+          <button type="button" id="process-all" class="btn" disabled>Обработать все</button>
+          <button type="button" id="clear" class="btn ghost" disabled>Очистить</button>
+        </div>
+      </section>
+
+      <section id="queue" class="queue" aria-live="polite"></section>
+    </section>
+  </main>
+
+  <script src="/app.js"></script>
+</body>
+</html>

internal/server/web/style.css

@@ -0,0 +1,309 @@
+:root {
+  --bg: #f5f7fa;
+  --panel: #ffffff;
+  --ink: #18202a;
+  --muted: #667085;
+  --line: #d8dee8;
+  --soft: #eef2f7;
+  --accent: #2563eb;
+  --accent-hover: #1d4ed8;
+  --accent-ink: #ffffff;
+  --ok: #15803d;
+  --warn: #b45309;
+  --err: #dc2626;
+}
+
+* { box-sizing: border-box; }
+html, body { margin: 0; padding: 0; }
+body {
+  min-height: 100vh;
+  font-family: -apple-system, BlinkMacSystemFont, "Inter", "Segoe UI", Roboto, sans-serif;
+  background: var(--bg);
+  color: var(--ink);
+  -webkit-font-smoothing: antialiased;
+  font-size: 15px;
+  line-height: 1.45;
+}
+
+button, input { font: inherit; }
+
+.topbar {
+  height: 56px;
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 0 28px;
+  border-bottom: 1px solid var(--line);
+  background: var(--panel);
+  position: sticky;
+  top: 0;
+  z-index: 10;
+}
+.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; }
+.brand .dot {
+  width: 12px;
+  height: 12px;
+  border-radius: 3px;
+  background: linear-gradient(135deg, var(--accent), #0f766e);
+}
+.brand .name { letter-spacing: 0; }
+.version { color: var(--muted); font-size: 12px; }
+
+.container {
+  width: min(1080px, 100%);
+  margin: 0 auto;
+  padding: 28px 24px 64px;
+}
+
+.workspace {
+  display: grid;
+  grid-template-columns: minmax(260px, 340px) 1fr;
+  grid-template-areas:
+    "intro controls"
+    "drop queue";
+  gap: 18px;
+  align-items: start;
+}
+
+.intro { grid-area: intro; }
+.intro h1 {
+  font-size: 26px;
+  letter-spacing: 0;
+  margin: 0 0 6px;
+  font-weight: 700;
+}
+.intro p { color: var(--muted); margin: 0; max-width: 560px; }
+
+.dropzone {
+  grid-area: drop;
+  min-height: 240px;
+  background: var(--panel);
+  border: 1.5px dashed #aab4c3;
+  border-radius: 8px;
+  padding: 28px 22px;
+  display: grid;
+  place-items: center;
+  text-align: center;
+  cursor: pointer;
+  transition: border-color .15s, background .15s, box-shadow .15s;
+}
+.dropzone:hover,
+.dropzone:focus {
+  border-color: var(--accent);
+  outline: none;
+  box-shadow: 0 0 0 3px rgba(37, 99, 235, .12);
+}
+.dropzone.drag {
+  border-color: var(--accent);
+  background: #eef5ff;
+}
+
+.dz-icon {
+  width: 42px;
+  height: 42px;
+  margin: 0 auto 14px;
+  border-radius: 8px;
+  background: var(--accent);
+  position: relative;
+}
+.dz-icon::before,
+.dz-icon::after {
+  content: "";
+  position: absolute;
+  background: var(--accent-ink);
+  border-radius: 2px;
+}
+.dz-icon::before { left: 19px; top: 10px; width: 4px; height: 18px; }
+.dz-icon::after { left: 12px; top: 17px; width: 18px; height: 4px; }
+
+.dz-title { font-weight: 700; font-size: 16px; margin-bottom: 4px; }
+.dz-sub { color: var(--muted); font-size: 13px; }
+.dz-sub button {
+  background: none;
+  border: none;
+  color: var(--accent);
+  cursor: pointer;
+  padding: 0;
+  text-decoration: underline;
+  text-underline-offset: 2px;
+}
+
+.controls {
+  grid-area: controls;
+  min-height: 72px;
+  background: var(--panel);
+  border: 1px solid var(--line);
+  border-radius: 8px;
+  padding: 14px;
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 16px;
+}
+.summary { min-width: 0; display: grid; gap: 2px; }
+.summary strong { font-size: 15px; }
+.summary span {
+  color: var(--muted);
+  font-size: 12px;
+  overflow-wrap: anywhere;
+}
+.actions { display: flex; gap: 8px; flex-wrap: wrap; justify-content: flex-end; }
+
+.queue {
+  grid-area: queue;
+  display: flex;
+  flex-direction: column;
+  gap: 10px;
+  min-width: 0;
+}
+
+.empty {
+  border: 1px dashed var(--line);
+  border-radius: 8px;
+  color: var(--muted);
+  min-height: 150px;
+  display: grid;
+  place-items: center;
+  background: rgba(255, 255, 255, .55);
+}
+
+.item {
+  background: var(--panel);
+  border: 1px solid var(--line);
+  border-radius: 8px;
+  padding: 14px;
+  display: grid;
+  grid-template-columns: minmax(0, 1fr) auto;
+  gap: 12px;
+  align-items: center;
+}
+.item .name {
+  font-weight: 650;
+  overflow-wrap: anywhere;
+}
+.item .meta {
+  color: var(--muted);
+  font-size: 12px;
+  margin-top: 2px;
+}
+.item .right {
+  display: flex;
+  gap: 8px;
+  align-items: center;
+  justify-content: flex-end;
+  flex-wrap: wrap;
+}
+.item .status {
+  min-width: 82px;
+  text-align: center;
+  font-size: 12px;
+  padding: 4px 8px;
+  border-radius: 999px;
+  background: var(--soft);
+  color: var(--muted);
+}
+.item.done .status { background: #e8f7ed; color: var(--ok); }
+.item.error .status { background: #fdecec; color: var(--err); }
+.item.run .status { background: #fff7e6; color: var(--warn); }
+
+.bar {
+  grid-column: 1 / -1;
+  height: 5px;
+  background: var(--soft);
+  border-radius: 999px;
+  overflow: hidden;
+}
+.bar > i {
+  display: block;
+  height: 100%;
+  width: 0;
+  background: linear-gradient(90deg, var(--accent), #0f766e);
+  transition: width .2s ease;
+}
+
+.btn {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  min-height: 34px;
+  background: var(--accent);
+  color: var(--accent-ink);
+  border: 1px solid var(--accent);
+  padding: 7px 12px;
+  border-radius: 7px;
+  font-size: 13px;
+  font-weight: 650;
+  cursor: pointer;
+  text-decoration: none;
+  white-space: nowrap;
+}
+.btn:hover { background: var(--accent-hover); border-color: var(--accent-hover); }
+.btn.ghost {
+  background: transparent;
+  color: var(--ink);
+  border-color: var(--line);
+}
+.btn.ghost:hover { background: var(--soft); border-color: #c7d0dd; }
+.btn:disabled {
+  opacity: .55;
+  cursor: not-allowed;
+}
+
+.icon-btn {
+  width: 34px;
+  height: 34px;
+  border: 1px solid var(--line);
+  border-radius: 7px;
+  background: transparent;
+  color: var(--muted);
+  cursor: pointer;
+  font-size: 18px;
+  line-height: 1;
+}
+.icon-btn:hover { background: var(--soft); color: var(--ink); }
+
+.report {
+  grid-column: 1 / -1;
+  font-size: 12px;
+  color: var(--muted);
+  background: #f8fafc;
+  border: 1px solid #e6ebf2;
+  padding: 10px 12px;
+  border-radius: 7px;
+  max-height: 180px;
+  overflow: auto;
+}
+.report-head {
+  color: var(--ink);
+  font-weight: 650;
+  margin-bottom: 6px;
+}
+.report pre {
+  margin: 0;
+  white-space: pre-wrap;
+  overflow-wrap: anywhere;
+  font-family: ui-monospace, "SF Mono", Menlo, monospace;
+}
+.error-text { color: var(--err); background: #fff7f7; border-color: #ffd9d9; }
+
+@media (max-width: 820px) {
+  .topbar { padding: 0 16px; }
+  .container { padding: 20px 14px 48px; }
+  .workspace {
+    grid-template-columns: 1fr;
+    grid-template-areas:
+      "intro"
+      "drop"
+      "controls"
+      "queue";
+  }
+  .dropzone { min-height: 190px; }
+  .controls {
+    align-items: stretch;
+    flex-direction: column;
+  }
+  .actions { justify-content: stretch; }
+  .actions .btn { flex: 1; }
+  .item { grid-template-columns: 1fr; }
+  .item .right { justify-content: flex-start; }
+}