html.go

package main

import (
	"bytes"
	"html/template"
	"io/fs"
	"os"
	"path/filepath"
)

func parseTemplates(dir string) (*template.Template, error) {
	tmpl := template.New("").Funcs(template.FuncMap{
		"md2html": func(s string) template.HTML {
			b := new(bytes.Buffer)
			err := md.Convert([]byte(s), b)
			if err != nil {
				return template.HTML("<p>failed to convert to html</p>")
			}
			return template.HTML(b.Bytes())
		},
	})

	err := filepath.WalkDir(dir, func(path string, d fs.DirEntry, err error) error {
		if filepath.Ext(d.Name()) == ".html" {
			_, err = tmpl.ParseFiles(path)
		}

		return err
	})
	if err != nil {
		return nil, err
	}

	return tmpl, nil
}

func toHTML[T any](tmpl *template.Template, layout, out string, data T) error {
	outFile, err := os.Create(out)
	if err != nil {
		return err
	}
	defer outFile.Close()

	err = tmpl.ExecuteTemplate(outFile, layout, data)
	if err != nil {
		return err
	}

	return nil
}