From 9a68591255747c82fd4ce99351bca6d43349cafa Mon Sep 17 00:00:00 2001
From: tjpcc <tjp@ctrl-c.club>
Date: Sun, 3 Sep 2023 19:58:18 -0600
Subject: implement gophernicus extensions for gophermaps

---
 gopher/gophermap/extended.go                       | 220 +++++++++++++++++++++
 gopher/gophermap/extended_test.go                  |  57 ++++++
 gopher/gophermap/listdir.go                        | 154 +++++++++++++++
 gopher/gophermap/parse.go                          |   4 +
 gopher/gophermap/testdata/customlist.gophermap     |  15 ++
 .../gophermap/testdata/customlist_output.gophermap |  12 ++
 gopher/gophermap/testdata/file1                    |   0
 gopher/gophermap/testdata/file2                    |   0
 gopher/gophermap/testdata/file3.executablething    |   0
 gopher/gophermap/testdata/file4                    |   0
 10 files changed, 462 insertions(+)
 create mode 100644 gopher/gophermap/extended.go
 create mode 100644 gopher/gophermap/extended_test.go
 create mode 100644 gopher/gophermap/listdir.go
 create mode 100644 gopher/gophermap/testdata/customlist.gophermap
 create mode 100644 gopher/gophermap/testdata/customlist_output.gophermap
 create mode 100644 gopher/gophermap/testdata/file1
 create mode 100644 gopher/gophermap/testdata/file2
 create mode 100644 gopher/gophermap/testdata/file3.executablething
 create mode 100644 gopher/gophermap/testdata/file4

(limited to 'gopher')

diff --git a/gopher/gophermap/extended.go b/gopher/gophermap/extended.go
new file mode 100644
index 0000000..d9fedd0
--- /dev/null
+++ b/gopher/gophermap/extended.go
@@ -0,0 +1,220 @@
+package gophermap
+
+import (
+	"bufio"
+	"errors"
+	"io"
+	"net/url"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"tildegit.org/tjp/sliderule/gopher"
+	"tildegit.org/tjp/sliderule/internal/types"
+)
+
+// ExtendedMapDocument is a gophermap doc with gophernicus's extensions
+//
+// These are documented at: gopher://gopher.gophernicus.org/0/docs/README.Gophermap
+type ExtendedMapDocument struct {
+	Lines    []gopher.MapItem
+	Location *url.URL
+}
+
+// ParseExtended parses a gophermap document including gophernicus extensions.
+func ParseExtended(input io.Reader, location *url.URL) (ExtendedMapDocument, error) {
+	rdr := bufio.NewReader(input)
+	doc := ExtendedMapDocument{Location: location}
+
+outer:
+	for num := 1; ; num += 1 {
+		line, err := rdr.ReadString('\n')
+		isEOF := errors.Is(err, io.EOF)
+		if err != nil && !isEOF {
+			return doc, err
+		}
+		line = strings.TrimRight(line, "\r\n")
+
+		if len(line) > 0 {
+			switch line[0] {
+
+			case '#':
+				doc.Lines = append(doc.Lines, gopher.MapItem{
+					Type:    CommentType,
+					Display: strings.TrimPrefix(line[1:], " "),
+				})
+				continue outer
+			case '!':
+				doc.Lines = append(doc.Lines, gopher.MapItem{
+					Type:    TitleType,
+					Display: line[1:],
+				})
+				continue outer
+			case '-':
+				doc.Lines = append(doc.Lines, gopher.MapItem{
+					Type:     HiddenType,
+					Selector: line[1:],
+				})
+				continue outer
+			case ':':
+				doc.Lines = append(doc.Lines, gopher.MapItem{
+					Type:    ExtensionType,
+					Display: line[1:],
+				})
+				continue outer
+			case '=':
+				doc.Lines = append(doc.Lines, gopher.MapItem{
+					Type:     InclusionType,
+					Selector: line[1:],
+				})
+				continue outer
+			}
+		}
+
+		switch line {
+		case "~":
+			doc.Lines = append(doc.Lines, gopher.MapItem{Type: UserListType})
+			continue outer
+		case "%":
+			doc.Lines = append(doc.Lines, gopher.MapItem{Type: VHostListType})
+			continue outer
+		case ".":
+			doc.Lines = append(doc.Lines, gopher.MapItem{Type: EndDocType})
+			break outer
+		case "*":
+			doc.Lines = append(doc.Lines, gopher.MapItem{Type: DirListType})
+			break outer
+		}
+
+		if !strings.Contains(line, "\t") {
+			doc.Lines = append(doc.Lines, gopher.MapItem{
+				Type:     gopher.InfoMessageType,
+				Display:  line,
+				Selector: location.Path,
+				Hostname: location.Hostname(),
+				Port:     location.Port(),
+			})
+			continue
+		}
+
+		item := gopher.MapItem{Type: types.Status(line[0])}
+
+		spl := strings.Split(line[1:], "\t")
+		if len(spl) != 4 {
+			return doc, InvalidLine(num)
+		}
+		item.Display = string(spl[0])
+		item.Selector = string(spl[1])
+		item.Hostname = string(spl[2])
+		item.Port = string(spl[3])
+		if _, err = strconv.Atoi(item.Port); err != nil {
+			return doc, InvalidLine(num)
+		}
+		doc.Lines = append(doc.Lines, item)
+
+		if isEOF {
+			break
+		}
+	}
+
+	return doc, nil
+}
+
+// Extensions to gopher types from Gophernicus.
+const (
+	// CommentType is omitted from generated compatible gophermaps.
+	CommentType types.Status = '#'
+
+	// TitleType defines the title of a gophermap document.
+	TitleType types.Status = '!'
+
+	// HiddenType hides a link from the generated compatible gophermap.
+	HiddenType types.Status = '-'
+
+	// ExtensionType defines the gopher type to use for files in the current directory with a given extension.
+	ExtensionType types.Status = ':'
+
+	// UserListType generates a list of users with valid ~/public_gopher directories.
+	UserListType types.Status = '~'
+
+	// VHostListType generates a listing of virtual hosts.
+	VHostListType types.Status = '%'
+
+	// InclusionType causes another gophermap to be included at this location.
+	InclusionType types.Status = '='
+
+	// DirListType stops parsing the current file and ends the generated gophermap with a listing of the current directory.
+	DirListType types.Status = '*'
+
+	// EndDocType ends the current gophermap file.
+	EndDocType types.Status = '.'
+)
+
+// Compatible builds a standards-compliant gophermap from the current extended menu.
+func (edoc ExtendedMapDocument) Compatible(cwd string) (gopher.MapDocument, string, error) {
+	doc := gopher.MapDocument{}
+
+	title := ""
+	hidden := map[string]struct{}{}
+	extensions := map[string]types.Status{}
+
+	for num, item := range edoc.Lines {
+		switch item.Type {
+		case CommentType:
+		case TitleType:
+			title = item.Display
+		case HiddenType:
+			hidden[item.Selector] = struct{}{}
+		case ExtensionType:
+			from, to, found := strings.Cut(item.Display, "=")
+			if !found {
+				return nil, "", InvalidLine(num)
+			}
+			extensions[from] = types.Status(to[0])
+		case UserListType: //TODO
+			return nil, "", errors.New("User listings '~' are not supported")
+		case VHostListType: //TODO
+			return nil, "", errors.New("Virtual host listings '%' are not supported")
+		case InclusionType:
+			location := filepath.Join(cwd, item.Selector)
+			subEdoc, err := openExtended(location, edoc.Location)
+			if err != nil {
+				return nil, "", err
+			}
+
+			lines, _, err := subEdoc.Compatible(filepath.Dir(location))
+			if err != nil {
+				return nil, "", err
+			}
+			doc = append(doc, lines...)
+		case DirListType:
+			dirlist, err := listDir(cwd, edoc.Location, hidden, extensions)
+			if err != nil {
+				return nil, "", err
+			}
+
+			doc = append(doc, dirlist...)
+
+			break
+		case EndDocType:
+			break
+		default:
+			doc = append(doc, item)
+		}
+	}
+
+	return doc, title, nil
+}
+
+func openExtended(path string, location *url.URL) (ExtendedMapDocument, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return ExtendedMapDocument{}, err
+	}
+	defer func() {
+		_ = file.Close()
+	}()
+
+	return ParseExtended(file, location)
+}
diff --git a/gopher/gophermap/extended_test.go b/gopher/gophermap/extended_test.go
new file mode 100644
index 0000000..e956df1
--- /dev/null
+++ b/gopher/gophermap/extended_test.go
@@ -0,0 +1,57 @@
+package gophermap
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/url"
+	"os"
+	"testing"
+)
+
+func TestExtendedDoc(t *testing.T) {
+	file, err := os.Open("testdata/customlist.gophermap")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	source := &bytes.Buffer{}
+	_, err = io.Copy(source, file)
+	_ = file.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	edoc, err := ParseExtended(source, &url.URL{
+		Scheme: "gopher",
+		Host:   "localhost.localdomain:70",
+		Path:   "/customlist.gophermap",
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	doc, _, err := edoc.Compatible("testdata")
+	if err != nil {
+		t.Fatal(err)
+	}
+	got := doc.String()
+
+	file, err = os.Open("testdata/customlist_output.gophermap")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	expected := &bytes.Buffer{}
+	_, err = io.Copy(expected, file)
+	_ = file.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if expected.String() != got {
+		fmt.Printf("expected:\n%s", expected.String())
+		fmt.Printf("got:\n%s", got)
+		t.Fatal("output mismatch")
+	}
+}
diff --git a/gopher/gophermap/listdir.go b/gopher/gophermap/listdir.go
new file mode 100644
index 0000000..8d66277
--- /dev/null
+++ b/gopher/gophermap/listdir.go
@@ -0,0 +1,154 @@
+package gophermap
+
+import (
+	"bufio"
+	"net/url"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+
+	"tildegit.org/tjp/sliderule/gopher"
+	"tildegit.org/tjp/sliderule/internal/types"
+)
+
+// ListDir builds a gopher menu representing the contents of a directory.
+func ListDir(dir string, location *url.URL) (gopher.MapDocument, error) {
+	return listDir(dir, location, nil, nil)
+}
+
+func listDir(dir string, location *url.URL, hidden map[string]struct{}, extensions map[string]types.Status) (gopher.MapDocument, error) {
+	contents, err := os.ReadDir(dir)
+	if err != nil {
+		return nil, err
+	}
+
+	doc := gopher.MapDocument{}
+
+	for _, entry := range contents {
+		name := entry.Name()
+
+		if _, ok := hidden[name]; ok || name == "gophermap" {
+			continue
+		}
+
+		var code types.Status
+
+		ext := strings.TrimPrefix(filepath.Ext(name), ".")
+		if entry.IsDir() {
+			code = gopher.MenuType
+		} else if c, ok := extensions[ext]; ok && ext != "" {
+			code = c
+		} else {
+			switch ext {
+			case "gophermap":
+				code = gopher.MenuType
+			case "exe", "bin", "out":
+				code = gopher.BinaryFileType
+			case "gif":
+				code = gopher.GifFileType
+			case "jpg", "jpeg", "tif", "tiff":
+				code = gopher.ImageFileType
+			case "bmp":
+				code = gopher.BitmapType
+			case "mp4", "mov", "avi", "wmv", "webm":
+				code = gopher.MovieFileType
+			case "pcm", "aiff", "mp3", "aac", "ogg", "wma", "flac", "alac":
+				code = gopher.SoundFileType
+			case "doc", "docx", "odt", "fodt":
+				code = gopher.DocumentType
+			case "html":
+				code = gopher.HTMLType
+			case "png":
+				code = gopher.PngImageFileType
+			case "rtf":
+				code = gopher.RtfDocumentType
+			case "wav":
+				code = gopher.WavSoundFileType
+			case "pdf":
+				code = gopher.PdfDocumentType
+			case "xml", "atom":
+				code = gopher.XmlDocumentType
+			default:
+				code = gopher.TextFileType
+			}
+		}
+
+		doc = append(doc, gopher.MapItem{
+			Type:     code,
+			Display:  displayName(dir, entry),
+			Selector: path.Join(path.Dir(location.Path), name),
+			Hostname: location.Hostname(),
+			Port:     location.Port(),
+		})
+	}
+
+	return doc, nil
+}
+
+func displayName(dir string, entry os.DirEntry) string {
+	fname := entry.Name()
+
+	// if is a gophermap, use !title or filename
+	if strings.HasSuffix(fname, ".gophermap") {
+		if title := gophermapTitle(dir, fname); title != "" {
+			return title
+		}
+		return fname
+	}
+
+	if entry.IsDir() {
+		if tag := tagTitle(dir, fname); tag != "" {
+			return tag
+		}
+
+		if title := gophermapTitle(dir, filepath.Join(fname, "gophermap")); title != "" {
+			return title
+		}
+	}
+
+	return fname
+}
+
+func gophermapTitle(dir, name string) string {
+	file, err := os.Open(filepath.Join(dir, name))
+	if err != nil {
+		return ""
+	}
+	defer func() {
+		_ = file.Close()
+	}()
+
+	rdr := bufio.NewReader(file)
+	line, err := rdr.ReadString('\n')
+	if err != nil {
+		return ""
+	}
+
+	if !strings.HasPrefix(line, "!") {
+		return ""
+	}
+	return strings.TrimRight(line[1:], "\r\n")
+}
+
+func tagTitle(parent, name string) string {
+	file, err := os.Open(filepath.Join(parent, name, "gophertag"))
+	if err != nil {
+		return ""
+	}
+	defer func() {
+		_ = file.Close()
+	}()
+
+	stat, err := file.Stat()
+	if err != nil || stat.IsDir() {
+		return ""
+	}
+
+	rdr := bufio.NewReader(file)
+	line, err := rdr.ReadString('\n')
+	if err != nil {
+		return ""
+	}
+	return strings.TrimRight(line, "\r\n")
+}
diff --git a/gopher/gophermap/parse.go b/gopher/gophermap/parse.go
index 3317514..04286bd 100644
--- a/gopher/gophermap/parse.go
+++ b/gopher/gophermap/parse.go
@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"strconv"
 
 	sr "tildegit.org/tjp/sliderule"
 	"tildegit.org/tjp/sliderule/gopher"
@@ -38,6 +39,9 @@ func Parse(input io.Reader) (gopher.MapDocument, error) {
 			item.Selector = string(spl[1])
 			item.Hostname = string(spl[2])
 			item.Port = string(spl[3])
+			if _, err = strconv.Atoi(item.Port); err != nil {
+				return nil, InvalidLine(num)
+			}
 
 			doc = append(doc, item)
 		}
diff --git a/gopher/gophermap/testdata/customlist.gophermap b/gopher/gophermap/testdata/customlist.gophermap
new file mode 100644
index 0000000..0d0c882
--- /dev/null
+++ b/gopher/gophermap/testdata/customlist.gophermap
@@ -0,0 +1,15 @@
+!This is the document title
+
+These should be info-message lines since they
+have no tab characters anywhere.
+
+# This is a comment!
+
+-file1
+-file2
+
+:executablething=9
+
+*
+
+this is unreachable
diff --git a/gopher/gophermap/testdata/customlist_output.gophermap b/gopher/gophermap/testdata/customlist_output.gophermap
new file mode 100644
index 0000000..1a96644
--- /dev/null
+++ b/gopher/gophermap/testdata/customlist_output.gophermap
@@ -0,0 +1,12 @@
+i	/customlist.gophermap	localhost.localdomain	70
+iThese should be info-message lines since they	/customlist.gophermap	localhost.localdomain	70
+ihave no tab characters anywhere.	/customlist.gophermap	localhost.localdomain	70
+i	/customlist.gophermap	localhost.localdomain	70
+i	/customlist.gophermap	localhost.localdomain	70
+i	/customlist.gophermap	localhost.localdomain	70
+i	/customlist.gophermap	localhost.localdomain	70
+1This is the document title	/customlist.gophermap	localhost.localdomain	70
+1customlist_output.gophermap	/customlist_output.gophermap	localhost.localdomain	70
+9file3.executablething	/file3.executablething	localhost.localdomain	70
+0file4	/file4	localhost.localdomain	70
+.
diff --git a/gopher/gophermap/testdata/file1 b/gopher/gophermap/testdata/file1
new file mode 100644
index 0000000..e69de29
diff --git a/gopher/gophermap/testdata/file2 b/gopher/gophermap/testdata/file2
new file mode 100644
index 0000000..e69de29
diff --git a/gopher/gophermap/testdata/file3.executablething b/gopher/gophermap/testdata/file3.executablething
new file mode 100644
index 0000000..e69de29
diff --git a/gopher/gophermap/testdata/file4 b/gopher/gophermap/testdata/file4
new file mode 100644
index 0000000..e69de29
-- 
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