gopher support.

Some of the contrib packages were originally built gemini-specific and
had to be refactored into generic core functionality and thin
protocol-specific wrappers for each of gemini and gopher.

1 files changed, 61 insertions, 0 deletions

diff --git a/gopher/gophermap/parse.go b/gopher/gophermap/parse.go
new file mode 100644
index 0000000..302aef0
--- /dev/null
+++ b/gopher/gophermap/parse.go
@@ -0,0 +1,61 @@
+package gophermap
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+
+	"tildegit.org/tjp/gus"
+	"tildegit.org/tjp/gus/gopher"
+)
+
+// Parse reads a gophermap document from a reader.
+func Parse(input io.Reader) (gopher.MapDocument, error) {
+	rdr := bufio.NewReader(input)
+	doc := gopher.MapDocument{}
+
+	num := 0
+	for {
+		num += 1
+		line, err := rdr.ReadBytes('\n')
+		isEOF := errors.Is(err, io.EOF)
+		if err != nil && !isEOF {
+			return nil, err
+		}
+
+		if len(line) > 2 && !bytes.Equal(line, []byte(".\r\n")) {
+			if line[len(line)-2] != '\r' || line[len(line)-1] != '\n' {
+				return nil, InvalidLine(num)
+			}
+
+			item := gopher.MapItem{Type: gus.Status(line[0])}
+
+			spl := bytes.Split(line[1:len(line)-2], []byte{'\t'})
+			if len(spl) != 4 {
+				return nil, InvalidLine(num)
+			}
+			item.Display = string(spl[0])
+			item.Selector = string(spl[1])
+			item.Hostname = string(spl[2])
+			item.Port = string(spl[3])
+
+			doc = append(doc, item)
+		}
+
+		if isEOF {
+			break
+		}
+	}
+
+	return doc, nil
+}
+
+// InvalidLine is returned from Parse when the reader contains a line which is invalid gophermap.
+type InvalidLine int
+
+// Error implements the error interface.
+func (il InvalidLine) Error() string {
+	return fmt.Sprintf("Invalid gophermap on line %d.", il)
+}