/
epub_zip_storage_image.go
100 lines (86 loc) · 1.87 KB
/
epub_zip_storage_image.go
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package epubzip
import (
"archive/zip"
"image"
"os"
"sync"
)
type StorageImageWriter struct {
fh *os.File
fz *zip.Writer
format string
mut *sync.Mutex
}
func NewStorageImageWriter(filename string, format string) (*StorageImageWriter, error) {
fh, err := os.Create(filename)
if err != nil {
return nil, err
}
fz := zip.NewWriter(fh)
return &StorageImageWriter{fh, fz, format, &sync.Mutex{}}, nil
}
func (e *StorageImageWriter) Close() error {
if err := e.fz.Close(); err != nil {
_ = e.fh.Close()
return err
}
return e.fh.Close()
}
func (e *StorageImageWriter) Add(filename string, img image.Image, quality int) error {
zipImage, err := CompressImage(filename, e.format, img, quality)
if err != nil {
return err
}
e.mut.Lock()
defer e.mut.Unlock()
fh, err := e.fz.CreateRaw(zipImage.Header)
if err != nil {
return err
}
_, err = fh.Write(zipImage.Data)
if err != nil {
return err
}
return nil
}
type StorageImageReader struct {
filename string
fh *os.File
fz *zip.Reader
files map[string]*zip.File
}
func NewStorageImageReader(filename string) (*StorageImageReader, error) {
fh, err := os.Open(filename)
if err != nil {
return nil, err
}
s, err := fh.Stat()
if err != nil {
return nil, err
}
fz, err := zip.NewReader(fh, s.Size())
if err != nil {
return nil, err
}
files := map[string]*zip.File{}
for _, z := range fz.File {
files[z.Name] = z
}
return &StorageImageReader{filename, fh, fz, files}, nil
}
func (e *StorageImageReader) Get(filename string) *zip.File {
return e.files[filename]
}
func (e *StorageImageReader) Size(filename string) uint64 {
img := e.Get(filename)
if img != nil {
return img.CompressedSize64 + 30 + uint64(len(img.Name))
}
return 0
}
func (e *StorageImageReader) Close() error {
return e.fh.Close()
}
func (e *StorageImageReader) Remove() error {
return os.Remove(e.filename)
}