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Diffstat (limited to 'gemini/gemtext/mdconv/convert.go')
| -rw-r--r-- | gemini/gemtext/mdconv/convert.go | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/gemini/gemtext/mdconv/convert.go b/gemini/gemtext/mdconv/convert.go new file mode 100644 index 0000000..c2f434d --- /dev/null +++ b/gemini/gemtext/mdconv/convert.go @@ -0,0 +1,78 @@ +package mdconv + +import ( + "io" + "text/template" + + "tildegit.org/tjp/gus/gemini/gemtext" + "tildegit.org/tjp/gus/gemini/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 + } + + 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 nil +} + +var baseTmpl = template.Must(template.New("mdconv").Parse(` +{{ define "header" }}{{ end }} +{{ define "textline" }}{{ if ne .String "\n" }} +{{ . }}{{ end }}{{ end }} +{{ define "linkline" }} +=> [{{ if eq .Label "" }}{{ .URL }}{{ else }}{{ .Label }}{{ end }}]({{ .URL }}) +{{ end }} +{{ define "preformattedtextlines" }}` + "\n```\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 }} +`)) |