d2/lib/ppt/presentation.go

101 lines
2 KiB
Go
Raw Normal View History

2023-04-04 14:13:47 +00:00
package ppt
import (
"archive/zip"
"bytes"
_ "embed"
"fmt"
"image/png"
"os"
)
type Pptx struct {
Slides []*Slide
}
type Slide struct {
Image []byte
Width int
Height int
}
func NewPresentation() *Pptx {
return &Pptx{}
}
func (p *Pptx) AddSlide(pngContent []byte) error {
src, err := png.Decode(bytes.NewReader(pngContent))
if err != nil {
return fmt.Errorf("error decoding PNG image: %v", err)
}
srcSize := src.Bounds().Size()
height := int(float64(SLIDE_WIDTH) * (float64(srcSize.X) / float64(srcSize.Y)))
p.Slides = append(p.Slides, &Slide{
Image: pngContent,
Width: SLIDE_WIDTH,
Height: height,
})
return nil
}
func (p *Pptx) SaveTo(filePath string) error {
// TODO: update core files with metadata
f, err := os.Create(filePath)
if err != nil {
return err
}
defer f.Close()
zipFile := zip.NewWriter(f)
defer zipFile.Close()
copyPptxTemplateTo(zipFile)
var slideFileNames []string
for i, slide := range p.Slides {
imageId := fmt.Sprintf("slide%dImage", i+1)
slideFileName := fmt.Sprintf("slide%d", i+1)
slideFileNames = append(slideFileNames, slideFileName)
imageWriter, err := zipFile.Create(fmt.Sprintf("ppt/media/%s.png", imageId))
if err != nil {
return err
}
_, err = imageWriter.Write(slide.Image)
if err != nil {
return err
}
err = addFile(zipFile, fmt.Sprintf("ppt/slides/_rels/%s.xml.rels", slideFileName), getRelsSlideXml(imageId))
if err != nil {
return err
}
// TODO: center the image?
err = addFile(zipFile, fmt.Sprintf("ppt/slides/%s.xml", slideFileName), getSlideXml(imageId, imageId, 0, 0, slide.Width, slide.Height))
if err != nil {
return err
}
}
err = addFile(zipFile, "[Content_Types].xml", getContentTypesXml(slideFileNames))
if err != nil {
return err
}
err = addFile(zipFile, "ppt/_rels/presentation.xml.rels", getPresentationXmlRels(slideFileNames))
if err != nil {
return err
}
err = addFile(zipFile, "ppt/presentation.xml", getPresentationXml(slideFileNames))
if err != nil {
return err
}
return nil
}