implement generate command

generate.go

@@ -6,6 +6,73 @@
 
 package main
 
+import (
+	_ "embed"
+	"errors"
+	"fmt"
+	"html/template"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+//go:embed news.xml.gotpl
+var newsTemplateStr string
+
 func Generate(scan ScanResult) {
-	fail("unimplemented")
+	//the XML prelude gets mangled by html.Template, so we print it manually
+	fmt.Println(`<?xml version="1.0" encoding="UTF-8"?>`)
+
+	t, err := template.New("news.xml").Funcs(funcs).Parse(newsTemplateStr)
+	must(err)
+	must(t.Execute(os.Stdout, scan))
+}
+
+//Functions for the news.xml.gotpl template.
+var funcs = map[string]interface{}{
+	"now": func() string {
+		return time.Now().Local().Format("2006-01-02T15:04:05")
+	},
+
+	"filesize": func(file string) (int64, error) {
+		fi, err := os.Stat(file)
+		if err != nil {
+			return 0, err
+		}
+		return fi.Size(), nil
+	},
+
+	"onlymp3": func(files []string) (string, error) {
+		for _, file := range files {
+			if strings.HasSuffix(file, ".mp3") {
+				return file, nil
+			}
+		}
+		return "", errors.New("no .mp3 audio file supplied")
+	},
+
+	"exceptmp3": func(files []string) (result []string) {
+		for _, file := range files {
+			if !strings.HasSuffix(file, ".mp3") {
+				result = append(result, file)
+			}
+		}
+		return
+	},
+
+	"mimetype": func(file string) (string, error) {
+		switch filepath.Ext(file) {
+		case ".mp3":
+			return "audio/mpeg", nil
+		case ".m4a":
+			return "audio/mp4", nil
+		case ".ogg":
+			return "audio/ogg", nil
+		case ".opus":
+			return "audio/opus", nil
+		default:
+			return "", errors.New("do not know MIME type for " + filepath.Ext(file))
+		}
+	},
 }

main.go

@@ -36,7 +36,7 @@ func fail(msg string, args ...interface{}) {
 	if len(args) > 0 {
 		msg = fmt.Sprintf(msg, args...)
 	}
-	fmt.Fprintln(os.Stderr, "ERROR: ", msg)
+	fmt.Fprintln(os.Stderr, "ERROR: "+msg)
 	os.Exit(1)
 }
 

news.xml.gotpl

@@ -0,0 +1,23 @@
+<!DOCTYPE item SYSTEM "https://www.c3d2.de/dtd/c3d2web.dtd">
+<item title="pentaradio24: {{ .Title }}" date="{{ now }}" author="{{ .AuthorNames }}">
+  <image title="(((pentaradio))">../pentaradio.png</image>
+  <p>{{ .Description }}</p>
+  <p>Shownotes:</p>
+  <ul>
+    <li><link href="https://ftp.c3d2.de/pentaradio/shownotes/shownotes-pentaradio-{{ printf "%04d-%02d-%02d" .Year .Month .Day }}.txt">Shownotes als Textdatei</link></li>
+    <li><link href="https://codimd.c3d2.de/pentaradio-{{ printf "%04d-%02d" .Year .Month }}">Shownotes als Webseite</link></li>
+  </ul>
+  <resource size="{{ filesize (onlymp3 .AudioFileNames) }}"
+            type="{{ mimetype (onlymp3 .AudioFileNames) }}"
+            url="https://ftp.c3d2.de/pentaradio/{{ onlymp3 .AudioFileNames }}"
+            title="pentaradio24 vom 22. März 2022">
+    {{- range (exceptmp3 .AudioFileNames) }}
+    <alternative size="{{ filesize . }}" type="{{ mimetype . }}" url="https://ftp.c3d2.de/pentaradio/{{ . }}"/>
+    {{- end }}
+    <chapters xmlns="https://podlove.de/simple-chapters">
+      {{- range .ChapterMarks }}
+      <chapter start="{{ .StartTime }}" title="{{ .Title }}" {{- if .URL }} href="{{ .URL }}" {{- end }} />
+      {{- end }}
+    </chapters>
+  </resource>
+</item>

scan.go

@@ -24,6 +24,7 @@ type ScanResult struct {
 	AudioFileNames []string
 	//parts extracted from the shownotes
 	Title       string
+	AuthorNames string
 	Description string
 	//parts extracted from the chaptermarks
 	ChapterMarks []ChapterMark
@@ -98,6 +99,7 @@ func (scan *ScanResult) ParseShownotes() {
 	shownotesRx := regexp.MustCompile(
 		fmt.Sprintf(`^# %s\n`, expectedTitle) + //header line
 			`# Titel: "(.*)"\n\n` + //episode title
+			`Mit (.*)\.\n\n` + //author names
 			`((?s:.*?))\n\n##\s`, //short description (everything up until the first <h2>)
 	)
 	match := shownotesRx.FindStringSubmatch(string(buf))
@@ -106,7 +108,8 @@ func (scan *ScanResult) ParseShownotes() {
 	}
 
 	scan.Title = match[1]
-	scan.Description = match[2]
+	scan.AuthorNames = match[2]
+	scan.Description = match[3]
 }
 
 func (scan ScanResult) ChapterMarksFile() string {