roulette/types/images/images.go

143 lines
3.4 KiB
Go

/*
Copyright © 2023 Seednode <seednode@seedno.de>
*/
package images
import (
"errors"
"fmt"
"image"
_ "image/gif"
_ "image/jpeg"
_ "image/png"
"math/rand"
"os"
"strings"
_ "golang.org/x/image/bmp"
_ "golang.org/x/image/webp"
"seedno.de/seednode/roulette/types"
)
type dimensions struct {
width int
height int
}
type Format struct {
Fun bool
}
func (t Format) Css() string {
var css strings.Builder
css.WriteString(`html,body{margin:0;padding:0;height:100%;}`)
css.WriteString(`a{color:inherit;display:block;height:100%;width:100%;text-decoration:none;}`)
css.WriteString(`img{margin:auto;display:block;max-width:97%;max-height:97%;`)
css.WriteString(`object-fit:scale-down;position:absolute;top:50%;left:50%;transform:translate(-50%,-50%)`)
if t.Fun {
rotate := rand.Intn(360)
css.WriteString(fmt.Sprintf(" rotate(%ddeg);", rotate))
css.WriteString(fmt.Sprintf("-ms-transform:rotate(%ddeg);", rotate))
css.WriteString(fmt.Sprintf("-webkit-transform:rotate(%ddeg);", rotate))
css.WriteString(fmt.Sprintf("-moz-transform:rotate(%ddeg);", rotate))
css.WriteString(fmt.Sprintf("-o-transform:rotate(%ddeg)", rotate))
}
css.WriteString(`;}`)
return css.String()
}
func (t Format) Title(rootUrl, fileUri, filePath, fileName, prefix, mime string) (string, error) {
dimensions, err := ImageDimensions(filePath)
if err != nil {
return "", err
}
return fmt.Sprintf(`<title>%s (%dx%d)</title>`,
fileName,
dimensions.width,
dimensions.height), nil
}
func (t Format) Body(rootUrl, fileUri, filePath, fileName, prefix, mime string) (string, error) {
dimensions, err := ImageDimensions(filePath)
if err != nil {
return "", err
}
return fmt.Sprintf(`<a href="%s"><img style="color: transparent;" onload="this.style.color='inherit'" onerror="this.style.color='inherit'" src="%s" width="%d" height="%d" type="%s" alt="Roulette selected: %s"></a>`,
rootUrl,
fileUri,
dimensions.width,
dimensions.height,
mime,
fileName), nil
}
func (t Format) Extensions() map[string]string {
return map[string]string{
`.apng`: `image/apng`,
`.avif`: `image/avif`,
`.bmp`: `image/bmp`,
`.gif`: `image/gif`,
`.jpg`: `image/jpeg`,
`.jpeg`: `image/jpeg`,
`.jfif`: `image/jpeg`,
`.pjp`: `image/jpeg`,
`.pjpeg`: `image/jpeg`,
`.png`: `image/png`,
`.webp`: `image/webp`,
}
}
func (t Format) Validate(filePath string) bool {
return true
}
func (t Format) MimeType(extension string) string {
extensions := t.Extensions()
value, exists := extensions[extension]
if exists {
return value
}
return ""
}
func ImageDimensions(path string) (*dimensions, error) {
file, err := os.Open(path)
switch {
case errors.Is(err, os.ErrNotExist):
fmt.Printf("File %s does not exist\n", path)
return &dimensions{}, nil
case err != nil:
fmt.Printf("File %s open returned error: %s\n", path, err)
return &dimensions{}, err
}
defer file.Close()
decodedConfig, _, err := image.DecodeConfig(file)
switch {
case errors.Is(err, image.ErrFormat):
fmt.Printf("File %s has invalid image format\n", path)
return &dimensions{width: 0, height: 0}, nil
case err != nil:
fmt.Printf("File %s decode returned error: %s\n", path, err)
return &dimensions{}, err
}
return &dimensions{width: decodedConfig.Width, height: decodedConfig.Height}, nil
}
func (t Format) Type() string {
return "embed"
}
func init() {
types.SupportedFormats.Register(Format{})
}