opengist/internal/render/highlight.go
2024-01-04 18:06:19 +01:00

148 lines
3.3 KiB
Go

package render
import (
"bufio"
"bytes"
"fmt"
"github.com/alecthomas/chroma/v2"
"github.com/alecthomas/chroma/v2/formatters/html"
"github.com/alecthomas/chroma/v2/lexers"
"github.com/alecthomas/chroma/v2/styles"
"github.com/rs/zerolog/log"
"github.com/thomiceli/opengist/internal/db"
"github.com/thomiceli/opengist/internal/git"
)
type RenderedFile struct {
*git.File
Type string `json:"type"`
Lines []string `json:"-"`
HTML string `json:"-"`
}
type RenderedGist struct {
*db.Gist
Lines []string
HTML string
}
func HighlightFile(file *git.File) (RenderedFile, error) {
rendered := RenderedFile{
File: file,
}
style := newStyle()
lexer := newLexer(file.Filename)
if lexer.Config().Name == "markdown" {
return MarkdownFile(file)
}
formatter := html.New(html.WithClasses(true), html.PreventSurroundingPre(true))
iterator, err := lexer.Tokenise(nil, file.Content)
if err != nil {
return rendered, err
}
htmlbuf := bytes.Buffer{}
w := bufio.NewWriter(&htmlbuf)
tokensLines := chroma.SplitTokensIntoLines(iterator.Tokens())
lines := make([]string, 0, len(tokensLines))
for _, tokens := range tokensLines {
iterator = chroma.Literator(tokens...)
err = formatter.Format(&htmlbuf, style, iterator)
if err != nil {
return rendered, fmt.Errorf("unable to format code: %w", err)
}
lines = append(lines, htmlbuf.String())
htmlbuf.Reset()
}
_ = w.Flush()
rendered.Lines = lines
rendered.Type = parseFileTypeName(*lexer.Config())
return rendered, err
}
func HighlightFiles(files []*git.File) ([]RenderedFile, error) {
renderedFiles := make([]RenderedFile, 0, len(files))
for _, file := range files {
rendered, err := HighlightFile(file)
if err != nil {
log.Warn().Err(err).Msg("Error rendering gist preview for " + file.Filename)
}
renderedFiles = append(renderedFiles, rendered)
}
return renderedFiles, nil
}
func HighlightGistPreview(gist *db.Gist) (RenderedGist, error) {
rendered := RenderedGist{
Gist: gist,
}
style := newStyle()
lexer := newLexer(gist.PreviewFilename)
if lexer.Config().Name == "markdown" {
return MarkdownGistPreview(gist)
}
formatter := html.New(html.WithClasses(true), html.PreventSurroundingPre(true))
iterator, err := lexer.Tokenise(nil, gist.Preview)
if err != nil {
return rendered, err
}
htmlbuf := bytes.Buffer{}
w := bufio.NewWriter(&htmlbuf)
tokensLines := chroma.SplitTokensIntoLines(iterator.Tokens())
lines := make([]string, 0, len(tokensLines))
for _, tokens := range tokensLines {
iterator = chroma.Literator(tokens...)
err = formatter.Format(&htmlbuf, style, iterator)
if err != nil {
return rendered, fmt.Errorf("unable to format code: %w", err)
}
lines = append(lines, htmlbuf.String())
htmlbuf.Reset()
}
_ = w.Flush()
rendered.Lines = lines
return rendered, err
}
func parseFileTypeName(config chroma.Config) string {
fileType := config.Name
if fileType == "fallback" || fileType == "plaintext" {
return "Text"
}
return fileType
}
func newLexer(filename string) chroma.Lexer {
var lexer chroma.Lexer
if lexer = lexers.Get(filename); lexer == nil {
lexer = lexers.Fallback
}
return lexer
}
func newStyle() *chroma.Style {
var style *chroma.Style
if style = styles.Get("catppuccin-latte"); style == nil {
style = styles.Fallback
}
return style
}