0.29.1原版

internal/markdown/parser/mention.go

@@ -0,0 +1,87 @@
+package parser
+
+import (
+	"unicode"
+	"unicode/utf8"
+
+	gast "github.com/yuin/goldmark/ast"
+	"github.com/yuin/goldmark/parser"
+	"github.com/yuin/goldmark/text"
+
+	mast "github.com/usememos/memos/internal/markdown/ast"
+)
+
+const (
+	// MaxMentionLength matches the username token length accepted by the API.
+	MaxMentionLength = 32
+)
+
+type mentionParser struct{}
+
+// NewMentionParser creates a new inline parser for @mention syntax.
+func NewMentionParser() parser.InlineParser {
+	return &mentionParser{}
+}
+
+// Trigger returns the characters that trigger this parser.
+func (*mentionParser) Trigger() []byte {
+	return []byte{'@'}
+}
+
+func isValidMentionRune(r rune) bool {
+	return unicode.IsLetter(r) || unicode.IsNumber(r) || r == '-'
+}
+
+func isMentionBoundary(r rune) bool {
+	return unicode.IsSpace(r) || unicode.IsPunct(r) || unicode.IsSymbol(r)
+}
+
+// Parse parses @mention syntax while avoiding email-address matches.
+func (*mentionParser) Parse(_ gast.Node, block text.Reader, _ parser.Context) gast.Node {
+	line, _ := block.PeekLine()
+	if len(line) == 0 || line[0] != '@' {
+		return nil
+	}
+
+	prev := block.PrecendingCharacter()
+	if prev != '\n' && !isMentionBoundary(prev) {
+		return nil
+	}
+
+	start := 1
+	pos := start
+	runeCount := 0
+	hasLetterOrNumber := false
+
+	for pos < len(line) {
+		r, size := utf8.DecodeRune(line[pos:])
+		if r == utf8.RuneError && size == 1 {
+			break
+		}
+		if !isValidMentionRune(r) {
+			break
+		}
+		if unicode.IsLetter(r) || unicode.IsNumber(r) {
+			hasLetterOrNumber = true
+		}
+		runeCount++
+		if runeCount > MaxMentionLength {
+			break
+		}
+		pos += size
+	}
+
+	if pos <= start || !hasLetterOrNumber {
+		return nil
+	}
+
+	username := line[start:pos]
+	usernameCopy := make([]byte, len(username))
+	copy(usernameCopy, username)
+
+	block.Advance(pos)
+
+	return &mast.MentionNode{
+		Username: usernameCopy,
+	}
+}