working basic navigation and marks

1 files changed, 201 insertions, 0 deletions

diff --git a/handlers.go b/handlers.go
new file mode 100644
index 0000000..587af68
--- /dev/null
+++ b/handlers.go
@@ -0,0 +1,201 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"mime"
+	"net/url"
+	"strings"
+
+	"tildegit.org/tjp/sliderule"
+	"tildegit.org/tjp/sliderule/gemini"
+	"tildegit.org/tjp/sliderule/gemini/gemtext"
+	"tildegit.org/tjp/sliderule/gopher"
+	"tildegit.org/tjp/sliderule/gopher/gophermap"
+)
+
+func docType(u *url.URL, response *sliderule.Response) string {
+	_, gopherType := gopherURL(u)
+	switch gopherType {
+	case gopher.MenuType:
+		return "text/x-gophermap"
+	case gopher.TextFileType, gopher.ErrorType, gopher.InfoMessageType:
+		return "text/plain"
+	case gopher.MacBinHexType,
+		gopher.DosBinType,
+		gopher.BinaryFileType,
+		gopher.ImageFileType,
+		gopher.MovieFileType,
+		gopher.SoundFileType,
+		gopher.DocumentType:
+		return "application/octet-stream"
+	case gopher.UuencodedType:
+		return "text/x-uuencode"
+	case gopher.GifFileType:
+		return "image/gif"
+	case gopher.BitmapType:
+		return "image/bmp"
+	case gopher.PngImageFileType:
+		return "image/png"
+	case gopher.HTMLType:
+		return "text/html"
+	case gopher.RtfDocumentType:
+		return "application/rtf"
+	case gopher.WavSoundFileType:
+		return "audio/wav"
+	case gopher.PdfDocumentType:
+		return "application/pdf"
+	case gopher.XmlDocumentType:
+		return "application/xml"
+	}
+
+	if u.Scheme == "gemini" {
+		if response.Status == gemini.StatusSuccess {
+			mtype, _, err := mime.ParseMediaType(response.Meta.(string))
+			if err == nil {
+				return mtype
+			}
+		}
+	}
+
+	return "text/plain"
+}
+
+func parseDoc(doctype string, body []byte, conf *Config) (string, []Link, error) {
+	switch doctype {
+	case "text/x-gophermap":
+		return parseGophermapDoc(body, conf.SoftWrap)
+	case "text/gemini":
+		return parseGemtextDoc(body, conf.SoftWrap)
+	}
+
+	return string(body), nil, nil
+}
+
+func parseGophermapDoc(body []byte, softWrap int) (string, []Link, error) {
+	var b strings.Builder
+	var l []Link
+	mapdoc, err := gophermap.Parse(bytes.NewBuffer(body))
+	if err != nil {
+		return "", nil, err
+	}
+
+	i := 0
+	for _, item := range mapdoc {
+		switch item.Type {
+		case gopher.InfoMessageType:
+			for _, line := range fold(item.Display, softWrap) {
+				if _, err := b.WriteString("      " + line + "\n"); err != nil {
+					return "", nil, err
+				}
+			}
+		default:
+			l = append(l, Link{
+				Text:   item.Display,
+				Target: fmtGopherURL(item.Type, item.Selector, item.Hostname, item.Port),
+			})
+			if _, err := b.WriteString(fmt.Sprintf("[%d]%s %s\n", i, linkSpaces(i), item.Display)); err != nil {
+				return "", nil, err
+			}
+			i += 1
+		}
+	}
+
+	return b.String(), l, nil
+}
+
+func parseGemtextDoc(body []byte, softWrap int) (string, []Link, error) {
+	var b strings.Builder
+	var l []Link
+	gemdoc, err := gemtext.Parse(bytes.NewBuffer(body))
+	if err != nil {
+		return "", nil, err
+	}
+
+	i := 0
+	for _, item := range gemdoc {
+		switch item.Type() {
+		case gemtext.LineTypeLink:
+			ll := item.(gemtext.LinkLine)
+			u, err := url.Parse(ll.URL())
+			if err != nil {
+				return "", nil, err
+			}
+			l = append(l, Link{
+				Text:   ll.Label(),
+				Target: u,
+			})
+			if _, err := b.WriteString(fmt.Sprintf("[%d]%s %s\n", i, linkSpaces(i), ll.Label())); err != nil {
+				return "", nil, err
+			}
+			i += 1
+		default:
+			for _, line := range fold(item.String(), softWrap) {
+				if _, err := b.WriteString("      " + line + "\n"); err != nil {
+					return "", nil, err
+				}
+			}
+		}
+	}
+
+	return b.String(), l, nil
+}
+
+func fold(line string, width int) []string {
+	rs := []rune(strings.TrimSuffix(line, "\n"))
+	if len(rs) == 0 {
+		return []string{""}
+	}
+
+	var b []string
+outer:
+	for len(rs) > 0 {
+		if len(rs) <= width {
+			b = append(b, string(rs))
+			break
+		}
+
+		w := width
+		for rs[w] != ' ' && w > 0 {
+			w -= 1
+		}
+		if w == 0 {
+			for i := width + 1; i < len(rs); i += 1 {
+				if rs[i] == ' ' {
+					b = append(b, string(rs[:i]))
+					rs = rs[i+1:]
+					continue outer
+				}
+			}
+			b = append(b, string(rs))
+			break outer
+		}
+
+		b = append(b, string(rs[:w]))
+		rs = rs[w+1:]
+	}
+
+	return b
+}
+
+func fmtGopherURL(itemtype sliderule.Status, selector, hostname, port string) *url.URL {
+	if port != "70" {
+		hostname += ":" + port
+	}
+	return &url.URL{
+		Scheme: "gopher",
+		Host:   hostname,
+		Path:   "/" + string(byte(itemtype)) + selector,
+	}
+}
+
+func linkSpaces(i int) string {
+	switch {
+	case i < 10:
+		return "  "
+	case i < 100:
+		return " "
+	default:
+		return ""
+	}
+}