feat: implement gomark parsers

plugin/gomark/parser/horizontal_rule.go

@@ -0,0 +1,39 @@
+package parser
+
+import (
+	"github.com/usememos/memos/plugin/gomark/ast"
+	"github.com/usememos/memos/plugin/gomark/parser/tokenizer"
+)
+
+type HorizontalRuleParser struct{}
+
+func NewHorizontalRuleParser() *HorizontalRuleParser {
+	return &HorizontalRuleParser{}
+}
+
+func (*HorizontalRuleParser) Match(tokens []*tokenizer.Token) (int, bool) {
+	if len(tokens) < 3 {
+		return 0, false
+	}
+	if tokens[0].Type != tokens[1].Type || tokens[0].Type != tokens[2].Type || tokens[1].Type != tokens[2].Type {
+		return 0, false
+	}
+	if tokens[0].Type != tokenizer.Dash && tokens[0].Type != tokenizer.Underline && tokens[0].Type != tokenizer.Asterisk {
+		return 0, false
+	}
+	if len(tokens) > 3 && tokens[3].Type != tokenizer.Newline {
+		return 0, false
+	}
+	return 3, true
+}
+
+func (p *HorizontalRuleParser) Parse(tokens []*tokenizer.Token) ast.Node {
+	size, ok := p.Match(tokens)
+	if size == 0 || !ok {
+		return nil
+	}
+
+	return &ast.HorizontalRule{
+		Symbol: tokens[0].Type,
+	}
+}