From 4c2630752f7367fff491a6ba53303e9102da7da0 Mon Sep 17 00:00:00 2001
From: tjpcc <tjp@ctrl-c.club>
Date: Sun, 15 Jan 2023 19:59:58 -0700
Subject: Completed markdown and HTML conversion.

---
 gemtext/mdconv/convert.go      | 104 ++++++++++++++++++++---------------------
 gemtext/mdconv/convert_test.go |   7 ++-
 2 files changed, 55 insertions(+), 56 deletions(-)

(limited to 'gemtext/mdconv')

diff --git a/gemtext/mdconv/convert.go b/gemtext/mdconv/convert.go
index 0c92f9f..9371d92 100644
--- a/gemtext/mdconv/convert.go
+++ b/gemtext/mdconv/convert.go
@@ -1,72 +1,72 @@
 package mdconv
 
 import (
-	"fmt"
 	"io"
 	"text/template"
 
 	"tildegit.org/tjp/gus/gemtext"
+	"tildegit.org/tjp/gus/gemtext/internal"
 )
 
+// Convert writes markdown to a writer from the provided gemtext document.
+//
+// Templates can be provided to override the output for different line types.
+// The templates supported are:
+//   - "header" is called before any lines and is passed the full Document.
+//   - "footer" is called after the lines and is passed the full Document.
+//   - "textline" is called once per line of text and is passed a gemtext.TextLine.
+//   - "linkline" is called once per link line and is passed a gemtext.LinkLine.
+//   - "preformattedtextlines" is called once for a block of preformatted text and is
+//     passed a slice of gemtext.PreformattedTextLines.
+//   - "heading1line" is called once per h1 line and is passed a gemtext.Heading1Line.
+//   - "heading2line" is called once per h2 line and is passed a gemtext.Heading2Line.
+//   - "heading3line" is called once per h3 line and is passed a gemtext.Heading3Line.
+//   - "listitemlines" is called once for a block of contiguous list item lines and
+//     is passed a slice of gemtext.ListItemLines.
+//   - "quoteline" is passed once per blockquote line and is passed a gemtext.QuoteLine.
+//
+// There exist default implementations of each of these templates, so the "overrides"
+// argument can be nil.
 func Convert(wr io.Writer, doc gemtext.Document, overrides *template.Template) error {
+	if err := internal.ValidateLinks(doc); err != nil {
+		return err
+	}
+
 	tmpl, err := baseTmpl.Clone()
 	if err != nil {
 		return err
 	}
 
-	if overrides != nil {
-		for _, override := range overrides.Templates() {
-			tmpl, err = tmpl.AddParseTree(override.Name(), override.Tree)
-			if err != nil {
-				return err
-			}
+	tmpl, err = internal.AddAllTemplates(tmpl, overrides)
+	if err != nil {
+		return err
+	}
+
+	for _, item := range internal.RenderItems(doc) {
+		if err := tmpl.ExecuteTemplate(wr, item.Template, item.Object); err != nil {
+			return err
 		}
 	}
 
-	return tmpl.ExecuteTemplate(wr, "mdconv", doc)
+	return nil
 }
 
-var baseTmpl = template.Must(template.New("mdconv").Parse(fmt.Sprintf((`
-{{block "header" .}}{{end -}}
-{{range . -}}
-{{if .Type | eq %d}}{{block "textline" . -}}
-	{{. -}}
-{{end -}}
-{{else if .Type | eq %d}}{{block "linkline" . -}}
-	=> [{{if eq .Label ""}}{{.URL}}{{else}}{{.Label}}{{end}}]({{.URL}})
-{{end -}}
-{{else if .Type | eq %d}}{{block "preformattoggleline" . -}}
-	` + "```" + `
-{{end -}}
-{{else if .Type | eq %d}}{{block "preformattedtextline" . -}}
-	{{. -}}
-{{end -}}
-{{else if .Type | eq %d}}{{block "heading1line" . -}}
-	# {{.Body}}
-{{end -}}
-{{else if .Type | eq %d}}{{block "heading2line" . -}}
-	## {{.Body}}
-{{end -}}
-{{else if .Type | eq %d}}{{block "heading3line" . -}}
-	### {{.Body}}
-{{end -}}
-{{else if .Type | eq %d}}{{block "listitemline" . -}}
-	* {{.Body}}
-{{end -}}
-{{else if .Type | eq %d}}{{block "quoteline" . -}}
-	> {{.Body}}
-{{end -}}
-{{end -}}
-{{end -}}
-{{block "footer" .}}{{end -}}
-`)[1:],
-	gemtext.LineTypeText,
-	gemtext.LineTypeLink,
-	gemtext.LineTypePreformatToggle,
-	gemtext.LineTypePreformattedText,
-	gemtext.LineTypeHeading1,
-	gemtext.LineTypeHeading2,
-	gemtext.LineTypeHeading3,
-	gemtext.LineTypeListItem,
-	gemtext.LineTypeQuote,
-)))
+var baseTmpl = template.Must(template.New("mdconv").Parse(`
+{{ define "header" }}{{ end }}
+{{ define "textline" }}{{ . }}{{ end }}
+{{ define "linkline" -}}
+	=> [{{ if eq .Label "" }}{{ .URL }}{{ else }}{{ .Label }}{{ end }}]({{ .URL }})
+{{ end }}
+{{ define "preformattedtextlines" }}` + "```\n" + `{{ range . }}{{ . }}{{ end }}` + "```\n" + `{{ end }}
+{{ define "heading1line" }}# {{ .Body }}
+{{ end }}
+{{ define "heading2line" }}## {{ .Body }}
+{{ end }}
+{{ define "heading3line" }}### {{ .Body }}
+{{ end }}
+{{ define "listitemlines" }}{{ range . }}* {{ .Body }}
+{{ end }}{{ end }}
+{{ define "quoteline" }}> {{ .Body }}
+{{ end }}
+{{ define "footer" }}{{ end }}
+`))
diff --git a/gemtext/mdconv/convert_test.go b/gemtext/mdconv/convert_test.go
index 6cde08b..010ddce 100644
--- a/gemtext/mdconv/convert_test.go
+++ b/gemtext/mdconv/convert_test.go
@@ -78,17 +78,16 @@ text:
 > quote:  this is a quote
 > quote:  -tjp
 text: 
-`[1:] + "pftoggle: ```\npf: doc := gemtext.Parse(req.Body)\npftoggle: ```\n"
+`[1:] + "```\npf: doc := gemtext.Parse(req.Body)\n```\n"
 
 	overrides := template.Must(template.New("overrides").Parse((`
 		{{define "textline"}}text: {{.}}{{end}}
 		{{define "linkline"}}=> link: [{{if eq .Label ""}}{{.URL}}{{else}}{{.Label}}{{end}}]({{.URL}})` + "\n" + `{{end}}
-		{{define "preformattoggleline"}}pftoggle: ` + "```\n" + `{{end}}
-		{{define "preformattedtextline"}}pf: {{.}}{{end}}
+		{{define "preformattedtextlines"}}` + "```\n" + `{{range . }}pf: {{.}}{{end}}` + "```\n" + `{{end}}
 		{{define "heading1line"}}# h1: {{.Body}}` + "\n" + `{{end}}
 		{{define "heading2line"}}## h2: {{.Body}}` + "\n" + `{{end}}
 		{{define "heading3line"}}### h3: {{.Body}}` + "\n" + `{{end}}
-		{{define "listitemline"}}* li: {{.Body}}` + "\n" + `{{end}}
+		{{define "listitemlines"}}{{range .}}* li: {{.Body}}` + "\n" + `{{end}}{{end}}
 		{{define "quoteline"}}> quote: {{.Body}}` + "\n" + `{{end}}
 		`)[1:]))
 
-- 
cgit v1.2.3