refactor gophermap template handling and add markdown conversion

1 files changed, 153 insertions, 0 deletions

diff --git a/gopher/gophermap/internal/templates.go b/gopher/gophermap/internal/templates.go
new file mode 100644
index 0000000..cc8ba14
--- /dev/null
+++ b/gopher/gophermap/internal/templates.go
@@ -0,0 +1,153 @@
+package internal
+
+import (
+	"bytes"
+	"text/template"
+	htemplate "html/template"
+	"strings"
+
+	"tildegit.org/tjp/sliderule/gopher"
+	"tildegit.org/tjp/sliderule/internal/types"
+)
+
+type renderItem struct {
+	Template string
+	Object   any
+}
+
+type renderRef struct {
+	Type     types.Status
+	Display  string
+	Selector htemplate.URL
+	Hostname string
+	Port     string
+}
+
+func simplifyLinks(items []renderItem, currentHost, currentPort string) {
+	for i, item := range items {
+		if item.Template != "link" && item.Template != "image" {
+			continue
+		}
+
+		m := item.Object.(renderRef)
+		if m.Hostname == currentHost && m.Port == currentPort {
+			m.Hostname = ""
+			m.Port = ""
+			m.Selector = htemplate.URL(strings.TrimPrefix(string(m.Selector), "URL:"))
+			items[i].Object = m
+		}
+	}
+}
+
+func AddOverrides(base *template.Template, overrides *template.Template) (*template.Template, error) {
+	if overrides == nil {
+		return base, nil
+	}
+
+	tmpl := base
+	var err error
+	for _, override := range overrides.Templates() {
+		tmpl, err = tmpl.AddParseTree(override.Name(), override.Tree)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return tmpl, nil
+}
+
+func AddHTMLOverrides(base *htemplate.Template, overrides *htemplate.Template) (*htemplate.Template, error) {
+	if overrides == nil {
+		return base, nil
+	}
+
+	tmpl := base
+	var err error
+	for _, override := range overrides.Templates() {
+		tmpl, err = tmpl.AddParseTree(override.Name(), override.Tree)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return tmpl, nil
+}
+
+func refItem(item gopher.MapItem) renderRef {
+	return renderRef{
+		Type:     item.Type,
+		Display:  item.Display,
+		Selector: htemplate.URL(item.Selector),
+		Hostname: item.Hostname,
+		Port:     item.Port,
+	}
+}
+
+func RenderItems(doc gopher.MapDocument) []renderItem {
+	out := make([]renderItem, 0, len(doc))
+	out = append(out, renderItem{
+		Template: "header",
+		Object:   doc,
+	})
+	inMsg := false
+	msg := &bytes.Buffer{}
+	var currentHost, currentPort string
+
+	for _, mapItem := range doc {
+		switch mapItem.Type {
+		case gopher.InfoMessageType:
+			if inMsg {
+				_, _ = msg.WriteString("\n")
+			} else {
+				msg.Reset()
+			}
+			_, _ = msg.WriteString(mapItem.Display)
+			inMsg = true
+
+			if currentHost == "" {
+				currentHost = mapItem.Hostname
+			}
+			if currentPort == "" {
+				currentPort = mapItem.Port
+			}
+		case gopher.GifFileType, gopher.ImageFileType, gopher.BitmapType, gopher.PngImageFileType:
+			if inMsg {
+				out = append(out, renderItem{
+					Template: "message",
+					Object:   msg.String(),
+				})
+				inMsg = false
+			}
+			out = append(out, renderItem{
+				Template: "image",
+				Object:   refItem(mapItem),
+			})
+		default:
+			if inMsg {
+				out = append(out, renderItem{
+					Template: "message",
+					Object:   msg.String(),
+				})
+				inMsg = false
+			}
+			out = append(out, renderItem{
+				Template: "link",
+				Object:   refItem(mapItem),
+			})
+		}
+	}
+
+	if inMsg {
+		out = append(out, renderItem{
+			Template: "message",
+			Object:   msg.String(),
+		})
+	}
+
+	simplifyLinks(out, currentHost, currentPort)
+
+	return append(out, renderItem{
+		Template: "footer",
+		Object:   doc,
+	})
+}