commit cfcd2ed6eb61656a8fcf75e417336624c7f26a8e
Author: m15o <m15o@pm.me>
Date:   Tue Nov 2 06:28:59 2021 +0100

    first commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..dd05eb9
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+.idea
+bin
+*~
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..867476b
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,2 @@
+build:
+	CGO_ENABLED=0 GOARCH=amd64 GOOS=linux go build -o bin/ni main.go
diff --git a/gmi2html/convert.go b/gmi2html/convert.go
new file mode 100644
index 0000000..59fd38f
--- /dev/null
+++ b/gmi2html/convert.go
@@ -0,0 +1,114 @@
+package gmi2html
+
+import (
+	"html"
+	"regexp"
+	"strings"
+)
+
+var heading1Regexp = regexp.MustCompile("^# (.*)$")
+var heading2Regexp = regexp.MustCompile("^## (.*)$")
+var heading3Regexp = regexp.MustCompile("^### (.*)$")
+var linkRegexp = regexp.MustCompile("^=> ([^\\s]+) ?(.+)?$")
+var blockquoteRegexp = regexp.MustCompile("^> (.*)$")
+var preRegexp = regexp.MustCompile("^```.*$")
+var bulletRegexp = regexp.MustCompile(`^\* ?(.*)$`)
+
+func clearLinkMode(linkMode *bool, rv *[]string) {
+	if *linkMode {
+		*rv = append(*rv, "</p>")
+		*linkMode = false
+	}
+}
+
+func clearUlMode(ulMode *bool, rv *[]string) {
+	if *ulMode {
+		*rv = append(*rv, "</ul>")
+		*ulMode = false
+	}
+}
+
+func sanitize(input string) string {
+	return html.EscapeString(input)
+}
+
+func Convert(gmi string) string {
+	var rv []string
+	preMode := false
+	ulMode := false
+	linkMode := false
+	for _, l := range strings.Split(gmi, "\n") {
+		l = strings.TrimRight(l, "\r")
+		if preMode {
+			switch {
+			case preRegexp.MatchString(l):
+				rv = append(rv, "</pre>")
+				preMode = false
+			default:
+				rv = append(rv, sanitize(l))
+			}
+		} else {
+			switch {
+			case heading1Regexp.MatchString(l):
+				clearUlMode(&ulMode, &rv)
+				clearLinkMode(&linkMode, &rv)
+				matches := heading1Regexp.FindStringSubmatch(l)
+				rv = append(rv, "<h1>"+sanitize(matches[1])+"</h1>")
+			case heading2Regexp.MatchString(l):
+				clearUlMode(&ulMode, &rv)
+				clearLinkMode(&linkMode, &rv)
+				matches := heading2Regexp.FindStringSubmatch(l)
+				rv = append(rv, "<h2>"+sanitize(matches[1])+"</h2>")
+			case heading3Regexp.MatchString(l):
+				clearUlMode(&ulMode, &rv)
+				clearLinkMode(&linkMode, &rv)
+				matches := heading3Regexp.FindStringSubmatch(l)
+				rv = append(rv, "<h3>"+sanitize(matches[1])+"</h3>")
+			case blockquoteRegexp.MatchString(l):
+				clearUlMode(&ulMode, &rv)
+				clearLinkMode(&linkMode, &rv)
+				matches := blockquoteRegexp.FindStringSubmatch(l)
+				rv = append(rv, "<blockquote>"+sanitize(matches[1])+"</blockquote>")
+			case linkRegexp.MatchString(l):
+				clearUlMode(&ulMode, &rv)
+				matches := linkRegexp.FindStringSubmatch(l)
+				if len(matches[2]) == 0 {
+					matches[2] = matches[1]
+				}
+				if strings.HasSuffix(matches[1], ".png") || strings.HasSuffix(matches[1], ".PNG") || strings.HasSuffix(matches[1], ".jpg") || strings.HasSuffix(matches[1], ".JPG") || strings.HasSuffix(matches[1], ".jpeg") || strings.HasSuffix(matches[1], ".gif") || strings.HasSuffix(matches[1], ".GIF") {
+					rv = append(rv, "<img src=\""+sanitize(matches[1])+"\"/>")
+					continue
+				}
+				if linkMode {
+					rv = append(rv, "<a href=\""+sanitize(matches[1])+"\">"+sanitize(matches[2])+"</a><br/>")
+					continue
+				}
+				rv = append(rv, "<p><a href=\""+sanitize(matches[1])+"\">"+sanitize(matches[2])+"</a><br/>")
+				linkMode = true
+			case preRegexp.MatchString(l):
+				clearUlMode(&ulMode, &rv)
+				clearLinkMode(&linkMode, &rv)
+				rv = append(rv, "<pre>")
+				preMode = true
+			case bulletRegexp.MatchString(l):
+				clearLinkMode(&linkMode, &rv)
+				matches := bulletRegexp.FindStringSubmatch(l)
+				if ulMode {
+					rv = append(rv, "<li>"+sanitize(matches[1])+"</li>")
+					continue
+				}
+				rv = append(rv, "<ul>\n<li>"+sanitize(matches[1])+"</li>")
+				ulMode = true
+			default:
+				clearUlMode(&ulMode, &rv)
+				clearLinkMode(&linkMode, &rv)
+				if len(l) != 0 {
+					rv = append(rv, "<p>"+sanitize(l)+"</p>")
+				}
+			}
+		}
+	}
+	clearUlMode(&ulMode, &rv)
+	clearLinkMode(&linkMode, &rv)
+	return strings.Join(rv, "\n")
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..a5fa878
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module ni
+
+go 1.16
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..8b561c9
--- /dev/null
+++ b/main.go
@@ -0,0 +1,156 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"html/template"
+	"io/ioutil"
+	"log"
+	"ni/gmi2html"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"sort"
+	"strings"
+	"time"
+)
+
+var tplPage = `
+{{ define "content" }}
+{{ .Content }}
+{{ if .Backlinks }}
+<h2>Backlinks</h2>
+<ul>
+{{ range .Backlinks }}
+<li><a href="/{{ . }}">{{ . }}</a></li>
+{{ end }}
+</ul>
+{{ end }}
+{{ end }}
+`
+
+var tplChangelog = `
+{{ define "content" }}
+<ul>
+{{ range . }}
+<li><a href="/{{ .Name }}">{{ .Name }}</a> {{ .TimeFormatted }}</li>
+{{ end }}
+</ul>
+{{ end }}
+`
+
+var filename = regexp.MustCompile(`^[a-z0-9\-]+\.gmi$`)
+var re = regexp.MustCompile(`\[\[([a-z0-9\-]+)\]\]`)
+var PageContent *template.Template
+var PageChangelog *template.Template
+
+func backlinks(in, name string) []string {
+	var rv []string
+	bl, err := exec.Command("/bin/sh", "-c", "grep -l  '\\[\\["+name[:len(name)-4]+"\\]\\]' "+in+"/*.gmi").Output()
+	if err != nil {
+		return rv
+	}
+	for _, link := range strings.Fields(string(bl)) {
+		oname := outputName(link[len(in+"/"):])
+		if oname != outputName(name) {
+			rv = append(rv, oname)
+		}
+	}
+	return rv
+}
+
+func process(in, name string, d []byte) []byte {
+	html := bytes.NewBufferString("")
+
+	err := PageContent.Execute(html, map[string]interface{}{
+		"Title":     name,
+		"Content":   template.HTML(re.ReplaceAllString(gmi2html.Convert(string(d)), `<a href="/$1.html">$1</a>`)),
+		"Backlinks": backlinks(in, name),
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+	return html.Bytes()
+}
+
+func buildChangelog(f []File) []byte {
+	html := bytes.NewBufferString("")
+	err := PageChangelog.Execute(html, f)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return html.Bytes()
+}
+
+type File struct {
+	Name          string
+	UpdatedAt     time.Time
+	TimeFormatted string
+}
+
+func outputName(inputName string) string {
+	return inputName[:len(inputName)-3] + "html"
+}
+
+func main() {
+	if len(os.Args) != 4 {
+		log.Fatal("Usage: ni input output template.html")
+	}
+
+	in := os.Args[1]
+	out := os.Args[2]
+	tpl := os.Args[3]
+
+	b, err := os.ReadFile(tpl)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	PageContent = template.Must(template.New("").Parse(string(b) + tplPage))
+	PageChangelog = template.Must(template.New("").Parse(string(b) + tplChangelog))
+
+	files, err := ioutil.ReadDir(in)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	var changelog []File
+
+	for _, file := range files {
+		if !filename.MatchString(file.Name()) {
+			continue
+		}
+		file, err := os.Stat(filepath.Join(in, file.Name()))
+		if err != nil {
+			log.Fatal(err)
+		}
+		updatedAt := file.ModTime()
+		changelog = append(changelog, File{
+			UpdatedAt:     updatedAt,
+			TimeFormatted: updatedAt.Format("2006-01-02"),
+			Name:          outputName(file.Name()),
+		})
+		data, err := os.ReadFile(filepath.Join(in, file.Name()))
+		if err != nil {
+			log.Fatal(err)
+		}
+		output := process(in, file.Name(), data)
+		err = os.WriteFile(filepath.Join(out, outputName(file.Name())), output, 0644)
+		if err != nil {
+			log.Fatal(err)
+		}
+		fmt.Print(".")
+	}
+	sort.Slice(changelog, func(i, j int) bool {
+		return changelog[i].UpdatedAt.After(changelog[j].UpdatedAt)
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+	err = os.WriteFile(filepath.Join(out, "changelog.html"), buildChangelog(changelog), 0644)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println("Done")
+}