2 files changed, 157 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)
+}
diff --git a/gopher/gophermap/parse_test.go b/gopher/gophermap/parse_test.go
new file mode 100644
index 0000000..0e5c09e
--- /dev/null
+++ b/gopher/gophermap/parse_test.go
@@ -0,0 +1,96 @@
+package gophermap_test
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"tildegit.org/tjp/gus/gopher"
+	"tildegit.org/tjp/gus/gopher/gophermap"
+)
+
+func TestParse(t *testing.T) {
+	tests := []struct {
+		doc   string
+		lines gopher.MapDocument
+	}{
+		{
+			doc: `
+iI am informational text		localhost	70
+icontinued on this line		localhost	70
+i		localhost	70
+0this is my text file	/file.txt	localhost	70
+i		localhost	70
+1here's a sub-menu	/sub/	localhost	70
+.
+`[1:],
+			lines: gopher.MapDocument{
+				gopher.MapItem{
+					Type:     gopher.InfoMessageType,
+					Display:  "I am informational text",
+					Selector: "",
+					Hostname: "localhost",
+					Port:     "70",
+				},
+				gopher.MapItem{
+					Type:     gopher.InfoMessageType,
+					Display:  "continued on this line",
+					Selector: "",
+					Hostname: "localhost",
+					Port:     "70",
+				},
+				gopher.MapItem{
+					Type:     gopher.InfoMessageType,
+					Display:  "",
+					Selector: "",
+					Hostname: "localhost",
+					Port:     "70",
+				},
+				gopher.MapItem{
+					Type:     gopher.TextFileType,
+					Display:  "this is my text file",
+					Selector: "/file.txt",
+					Hostname: "localhost",
+					Port:     "70",
+				},
+				gopher.MapItem{
+					Type:     gopher.InfoMessageType,
+					Display:  "",
+					Selector: "",
+					Hostname: "localhost",
+					Port:     "70",
+				},
+				gopher.MapItem{
+					Type:     gopher.MenuType,
+					Display:  "here's a sub-menu",
+					Selector: "/sub/",
+					Hostname: "localhost",
+					Port:     "70",
+				},
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.lines[0].Display, func(t *testing.T) {
+			text := strings.ReplaceAll(test.doc, "\n", "\r\n")
+			doc, err := gophermap.Parse(bytes.NewBufferString(text))
+			require.Nil(t, err)
+
+			if assert.Equal(t, len(test.lines), len(doc)) {
+				for i, line := range doc {
+					expect := test.lines[i]
+
+					assert.Equal(t, expect.Type, line.Type)
+					assert.Equal(t, expect.Display, line.Display)
+					assert.Equal(t, expect.Selector, line.Selector)
+					assert.Equal(t, expect.Hostname, line.Hostname)
+					assert.Equal(t, expect.Port, line.Port)
+				}
+			}
+		})
+	}
+}