move ExternalPointer to nip73 and write nip27.Parse() that gets all the parts of the text including URLs, Nostr URIs and just raw text.

nip22/nip22.go

@@ -1,6 +1,9 @@
 package nip22
 
-import "github.com/nbd-wtf/go-nostr"
+import (
+	"github.com/nbd-wtf/go-nostr"
+	"github.com/nbd-wtf/go-nostr/nip73"
+)
 
 func GetThreadRoot(tags nostr.Tags) nostr.Pointer {
 	for _, tag := range tags {
@@ -15,7 +18,7 @@ func GetThreadRoot(tags nostr.Tags) nostr.Pointer {
 			ep, _ := nostr.EntityPointerFromTag(tag)
 			return ep
 		case "I":
-			ep, _ := nostr.ExternalPointerFromTag(tag)
+			ep, _ := nip73.ExternalPointerFromTag(tag)
 			return ep
 		}
 	}
@@ -35,7 +38,7 @@ func GetImmediateParent(tags nostr.Tags) nostr.Pointer {
 			ep, _ := nostr.EntityPointerFromTag(tag)
 			return ep
 		case "i":
-			ep, _ := nostr.ExternalPointerFromTag(tag)
+			ep, _ := nip73.ExternalPointerFromTag(tag)
 			return ep
 		}
 	}

nip27/blocks.go

@@ -0,0 +1,152 @@
+package nip27
+
+import (
+	"iter"
+	"net/url"
+	"regexp"
+	"strings"
+
+	"github.com/nbd-wtf/go-nostr"
+	"github.com/nbd-wtf/go-nostr/nip19"
+	"github.com/nbd-wtf/go-nostr/nip73"
+)
+
+type Block struct {
+	Text    string
+	Start   int
+	Pointer nostr.Pointer
+}
+
+var (
+	noCharacter    = regexp.MustCompile(`(?m)\W`)
+	noURLCharacter = regexp.MustCompile(`(?m)\W |\W$|$|,| `)
+)
+
+func Parse(content string) iter.Seq[Block] {
+	return func(yield func(Block) bool) {
+		max := len(content)
+		index := 0
+		prevIndex := 0
+
+		for index < max {
+			pu := strings.IndexRune(content[index:], ':')
+			if pu == -1 {
+				// reached end
+				break
+			}
+			u := pu + index
+
+			switch {
+			case u >= 5 && content[u-5:u] == "nostr" && u+60 < max:
+				m := noCharacter.FindStringIndex(content[u+60:])
+				end := max
+				if m != nil {
+					end = u + 60 + m[0]
+				}
+
+				prefix, data, err := nip19.Decode(content[u+1 : end])
+				if err != nil {
+					// ignore this, not a valid nostr uri
+					index = u + 1
+					continue
+				}
+
+				var pointer nostr.Pointer
+				switch prefix {
+				case "npub":
+					pointer = nostr.ProfilePointer{PublicKey: data.(string)}
+				case "nprofile", "nevent", "naddr":
+					pointer = data.(nostr.Pointer)
+				case "note", "nsec":
+					fallthrough // I'm so cool
+				default:
+					// ignore this, treat it as not a valid uri
+					index = end + 1
+					continue
+				}
+
+				if prevIndex != u-5 {
+					if !yield(Block{Text: content[prevIndex : u-5], Start: prevIndex}) {
+						return
+					}
+				}
+
+				if !yield(Block{Pointer: pointer, Text: content[u-5 : end], Start: u - 5}) {
+					return
+				}
+
+				index = end
+				prevIndex = index
+				continue
+			case (u >= 5 && content[u-5:u] == "https") || (u >= 4 && content[u-4:u] == "http"):
+				m := noURLCharacter.FindStringIndex(content[u+4:])
+				end := max
+				if m != nil {
+					end = u + 4 + m[0]
+				}
+				prefixLen := 4
+				if content[u-1] == 's' {
+					prefixLen = 5
+				}
+				parsed, err := url.Parse(content[u-prefixLen : end])
+				if err != nil || !strings.Contains(parsed.Host, ".") {
+					// ignore this, not a valid url
+					index = end + 1
+					continue
+				}
+
+				if prevIndex != u-prefixLen {
+					if !yield(Block{Text: content[prevIndex : u-prefixLen], Start: prevIndex}) {
+						return
+					}
+				}
+
+				if !yield(Block{Pointer: nip73.ExternalPointer{Thing: content[u-prefixLen : end]}, Text: content[u-prefixLen : end], Start: u - prefixLen}) {
+					return
+				}
+
+				index = end
+				prevIndex = index
+				continue
+			case (u >= 3 && content[u-3:u] == "wss") || (u >= 2 && content[u-2:u] == "ws"):
+				m := noURLCharacter.FindStringIndex(content[u+4:])
+				end := max
+				if m != nil {
+					end = u + 4 + m[0]
+				}
+				prefixLen := 2
+				if content[u-1] == 's' {
+					prefixLen = 3
+				}
+				parsed, err := url.Parse(content[u-prefixLen : end])
+				if err != nil || !strings.Contains(parsed.Host, ".") {
+					// ignore this, not a valid url
+					index = end + 1
+					continue
+				}
+
+				if prevIndex != u-prefixLen {
+					if !yield(Block{Text: content[prevIndex : u-prefixLen], Start: prevIndex}) {
+						return
+					}
+				}
+
+				if !yield(Block{Pointer: nip73.ExternalPointer{Thing: content[u-prefixLen : end]}, Text: content[u-prefixLen : end], Start: u - prefixLen}) {
+					return
+				}
+
+				index = end
+				prevIndex = index
+				continue
+			default:
+				// ignore this, it is nothing
+				index = u + 1
+				continue
+			}
+		}
+
+		if prevIndex != max {
+			yield(Block{Text: content[prevIndex:], Start: prevIndex})
+		}
+	}
+}

nip27/blocks_test.go

@@ -0,0 +1,50 @@
+package nip27
+
+import (
+	"fmt"
+	"slices"
+	"testing"
+
+	"github.com/nbd-wtf/go-nostr"
+	"github.com/nbd-wtf/go-nostr/nip73"
+	"github.com/stretchr/testify/require"
+)
+
+func TestParse(t *testing.T) {
+	for i, tc := range []struct {
+		content  string
+		expected []Block
+	}{
+		{
+			"hello, nostr:nprofile1qqsvc6ulagpn7kwrcwdqgp797xl7usumqa6s3kgcelwq6m75x8fe8yc5usxdg wrote nostr:nevent1qqsvc6ulagpn7kwrcwdqgp797xl7usumqa6s3kgcelwq6m75x8fe8ychxp5v4!",
+			[]Block{
+				{Text: "hello, ", Start: 0},
+				{Text: "nostr:nprofile1qqsvc6ulagpn7kwrcwdqgp797xl7usumqa6s3kgcelwq6m75x8fe8yc5usxdg", Start: 7, Pointer: nostr.ProfilePointer{PublicKey: "cc6b9fea033f59c3c39a0407c5f1bfee439b077508d918cfdc0d6fd431d39393"}},
+				{Text: " wrote ", Start: 83},
+				{Text: "nostr:nevent1qqsvc6ulagpn7kwrcwdqgp797xl7usumqa6s3kgcelwq6m75x8fe8ychxp5v4", Start: 90, Pointer: nostr.EventPointer{ID: "cc6b9fea033f59c3c39a0407c5f1bfee439b077508d918cfdc0d6fd431d39393"}},
+				{Text: "!", Start: 164},
+			},
+		},
+		{
+			`:wss://oa.ao; this was a relay and now here's a video -> https://videos.com/video.mp4! and some music: http://music.com/song.mp3
+and a regular link: https://regular.com/page?ok=true. and now a broken link: https://kjxkxk and a broken nostr ref: nostr:nevent1qqsr0f9w78uyy09qwmjt0kv63j4l7sxahq33725lqyyp79whlfjurwspz4mhxue69uhh56nzv34hxcfwv9ehw6nyddhq0ag9xg and a fake nostr ref: nostr:llll ok but finally https://ok.com!`,
+			[]Block{
+				{Text: ":", Start: 0},
+				{Text: "wss://oa.ao", Start: 1, Pointer: nip73.ExternalPointer{Thing: "wss://oa.ao"}},
+				{Text: "; this was a relay and now here's a video -> ", Start: 12},
+				{Text: "https://videos.com/video.mp4", Start: 57, Pointer: nip73.ExternalPointer{Thing: "https://videos.com/video.mp4"}},
+				{Text: "! and some music: ", Start: 85},
+				{Text: "http://music.com/song.mp3", Start: 103, Pointer: nip73.ExternalPointer{Thing: "http://music.com/song.mp3"}},
+				{Text: "\nand a regular link: ", Start: 128},
+				{Text: "https://regular.com/page?ok=true", Start: 149, Pointer: nip73.ExternalPointer{Thing: "https://regular.com/page?ok=true"}},
+				{Text: ". and now a broken link: https://kjxkxk and a broken nostr ref: nostr:nevent1qqsr0f9w78uyy09qwmjt0kv63j4l7sxahq33725lqyyp79whlfjurwspz4mhxue69uhh56nzv34hxcfwv9ehw6nyddhq0ag9xg and a fake nostr ref: nostr:llll ok but finally ", Start: 181},
+				{Text: "https://ok.com", Start: 405, Pointer: nip73.ExternalPointer{Thing: "https://ok.com"}},
+				{Text: "!", Start: 419},
+			},
+		},
+	} {
+		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
+			require.Equal(t, tc.expected, slices.Collect(Parse(tc.content)))
+		})
+	}
+}

nip27/references.go

@@ -17,6 +17,7 @@ type Reference struct {
 
 var mentionRegex = regexp.MustCompile(`\bnostr:((note|npub|naddr|nevent|nprofile)1\w+)\b`)
 
+// Deprecated: this is useless, use Parse() isntead (but the semantics is different)
 func ParseReferences(evt nostr.Event) iter.Seq[Reference] {
 	return func(yield func(Reference) bool) {
 		for _, ref := range mentionRegex.FindAllStringSubmatchIndex(evt.Content, -1) {

nip73/pointer.go

@@ -0,0 +1,23 @@
+package nip73
+
+import "github.com/nbd-wtf/go-nostr"
+
+var _ nostr.Pointer = (*ExternalPointer)(nil)
+
+// ExternalPointer represents a pointer to a URL or something else.
+type ExternalPointer struct {
+	Thing string
+}
+
+// ExternalPointerFromTag creates a ExternalPointer from an "i" tag
+func ExternalPointerFromTag(refTag nostr.Tag) (ExternalPointer, error) {
+	return ExternalPointer{refTag[1]}, nil
+}
+
+func (ep ExternalPointer) MatchesEvent(_ nostr.Event) bool { return false }
+func (ep ExternalPointer) AsTagReference() string          { return ep.Thing }
+func (ep ExternalPointer) AsFilter() nostr.Filter          { return nostr.Filter{} }
+
+func (ep ExternalPointer) AsTag() nostr.Tag {
+	return nostr.Tag{"i", ep.Thing}
+}

pointers.go

@@ -26,7 +26,6 @@ var (
 	_ Pointer = (*ProfilePointer)(nil)
 	_ Pointer = (*EventPointer)(nil)
 	_ Pointer = (*EntityPointer)(nil)
-	_ Pointer = (*ExternalPointer)(nil)
 )
 
 // ProfilePointer represents a pointer to a Nostr profile.
@@ -174,21 +173,3 @@ func (ep EntityPointer) AsTag() Tag {
 	}
 	return Tag{"a", ep.AsTagReference()}
 }
-
-// ExternalPointer represents a pointer to a Nostr profile.
-type ExternalPointer struct {
-	Thing string
-}
-
-// ExternalPointerFromTag creates a ExternalPointer from an "i" tag
-func ExternalPointerFromTag(refTag Tag) (ExternalPointer, error) {
-	return ExternalPointer{refTag[1]}, nil
-}
-
-func (ep ExternalPointer) MatchesEvent(_ Event) bool { return false }
-func (ep ExternalPointer) AsTagReference() string    { return ep.Thing }
-func (ep ExternalPointer) AsFilter() Filter          { return Filter{} }
-
-func (ep ExternalPointer) AsTag() Tag {
-	return Tag{"i", ep.Thing}
-}