package main
import (
"bufio"
"bytes"
"fmt"
"html/template"
"io/ioutil"
"os"
"regexp"
"strings"
"github.com/microcosm-cc/bluemonday"
"github.com/russross/blackfriday"
yaml "gopkg.in/yaml.v2"
)
const delim = "---"
type post struct {
Title string
Published bool
Description string
Tags []string
CoverImage string
Series string
PostBody template.HTML
}
var templ = `<!DOCTYPE html>
<html lang="en">
<head>
<title>{{.Title}}</title>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="HandheldFriendly" content="True">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="referrer" content="no-referrer-when-downgrade" />
<meta name="description" content="{{.Description}}" />
</head>
<body>
<div class="post">
<h1>{{.Title}}</h1>
{{.PostBody}}
</div>
</body>
</html>
`
func getContents(f *string) ([]byte, error) {
b, err := ioutil.ReadFile(*f)
if err != nil {
return nil, err
}
return b, nil
}
func parseFM(b *[]byte) (map[string]interface{}, error) {
m := make(map[string]interface{})
err := yaml.Unmarshal(*b, &m)
if err != nil {
msg := fmt.Sprintf("error: %v\ninput:\n%s", err, b)
return nil, fmt.Errorf(msg)
}
return m, nil
}
func isNil(i interface{}) bool {
if i != nil {
return false
}
return true
}
func splitData(f *[]byte) ([][]byte, error) {
b := bytes.Split(*f, []byte(delim))
if len(b) < 3 || len(b[0]) != 0 {
return nil, fmt.Errorf("Front matter is damaged")
}
return b, nil
}
// makePost creates the post struct, returns that and the template HTML
func makePost(fm map[string]interface{}, contents []byte,
s [][]byte) (*template.Template, *post) {
p := &post{}
if isNil(fm["title"]) {
panic("isNil tripped at title")
} else {
p.Title = fm["title"].(string)
}
p.Published = fm["published"].(bool)
p.Description = fm["description"].(string)
// TODO: Strip space after comma prior to parse?
tmp := fm["tags"].(string)
p.Tags = strings.Split(tmp, ", ")
p.CoverImage = fm["cover_image"].(string)
p.Series = fm["series"].(string)
pBody := contents[len(s[1])+(len(delim)*2):]
out := blackfriday.Run(pBody)
bm := bluemonday.UGCPolicy()
bm.AllowAttrs("class").Matching(regexp.MustCompile("^language-[a-zA-Z0-9]+$")).OnElements("code")
p.PostBody = template.HTML(bm.SanitizeBytes(out))
tm := template.Must(template.New("msg").Parse(templ))
return tm, p
}
func main() {
d, err := ioutil.ReadDir(".")
if err != nil {
panic(err)
}
for _, f := range d {
if t := f.Name(); strings.HasSuffix(t, ".md") {
contents, err := getContents(&t)
if err != nil {
panic(err)
}
s, err := splitData(&contents)
if err != nil {
panic(err)
}
fm, err := parseFM(&s[1])
if err != nil {
msg := fmt.Sprintf("error: %v\ninput:\n%s", err, s[1])
panic(msg)
}
tm, p := makePost(fm, contents, s)
fin := strings.TrimSuffix(t, ".md")
o, err := os.Create(fin + ".html")
if err != nil {
panic(err)
}
defer o.Close()
buf := bufio.NewWriter(o)
err = tm.Execute(buf, p)
if err != nil {
panic(err)
}
buf.Flush()
}
}
}