From 3ca7852eb2e2ec53e09e09db0e593bd0e7c82121 Mon Sep 17 00:00:00 2001
From: Mauricio Massa <mmassa2137@outlook.com>
Date: Fri, 3 Jan 2025 16:50:55 -0500
Subject: [PATCH] add support for ltm rules

---
 ast/ast.go          | 17 +++++++++++++++++
 parser/parser.go    | 34 +++++++++++++++++++++++++++++-----
 test-data/ltm.irule |  9 +++++++++
 token/token.go      |  4 ++++
 4 files changed, 59 insertions(+), 5 deletions(-)
 create mode 100644 test-data/ltm.irule

diff --git a/ast/ast.go b/ast/ast.go
index a6cbdaf..6a6d468 100644
--- a/ast/ast.go
+++ b/ast/ast.go
@@ -752,3 +752,20 @@ func (ns *NodeStatement) TokenLiteral() string { return ns.Token.Literal }
 func (ns *NodeStatement) String() string {
 	return fmt.Sprintf("node %s %s", ns.IPAddress, ns.Port)
 }
+
+type LtmRule struct {
+	Token token.Token
+	Name  *Identifier
+	Body  *BlockStatement
+}
+
+func (lr *LtmRule) statementNode()       {}
+func (lr *LtmRule) TokenLiteral() string { return lr.Token.Literal }
+func (lr *LtmRule) String() string {
+	var out bytes.Buffer
+	out.WriteString("ltm rule ")
+	out.WriteString(lr.Name.String())
+	out.WriteString(" ")
+	out.WriteString(lr.Body.String())
+	return out.String()
+}
diff --git a/parser/parser.go b/parser/parser.go
index ad0c3fa..383a3e6 100644
--- a/parser/parser.go
+++ b/parser/parser.go
@@ -286,6 +286,8 @@ func (p *Parser) parseStatement() ast.Statement {
 		stmt = p.parseBlockStatement()
 	case token.SWITCH:
 		stmt = p.parseSwitchStatement()
+	case token.LTM:
+		stmt = p.parseLtmRule()
 	default:
 		stmt = p.parseExpressionStatement()
 	}
@@ -2188,15 +2190,37 @@ func (p *Parser) parseNodeStatement() ast.Expression {
 	}
 	nodeStmt.IPAddress = p.curToken.Literal
 
-	// Expect the next token to be a port number
-	if !p.expectPeek(token.NUMBER) {
-		return nil
+	// Expect the next token to be a port number, but don't require it
+	if p.peekTokenIs(token.NUMBER) {
+		p.nextToken()
+		nodeStmt.Port = p.curToken.Literal
 	}
-	nodeStmt.Port = p.curToken.Literal
 
 	if config.DebugMode {
-		fmt.Printf("DEBUG: parseNodeStatement End\n")
+		fmt.Printf("DEBUG: parseNodeStatement End - IP: %s, Port: %s\n", nodeStmt.IPAddress, nodeStmt.Port)
 	}
 
 	return nodeStmt
 }
+
+func (p *Parser) parseLtmRule() ast.Statement {
+	stmt := &ast.LtmRule{Token: p.curToken}
+
+	if !p.expectPeek(token.RULE) {
+		return nil
+	}
+
+	if !p.expectPeek(token.IDENT) {
+		return nil
+	}
+
+	stmt.Name = &ast.Identifier{Token: p.curToken, Value: p.curToken.Literal}
+
+	if !p.expectPeek(token.LBRACE) {
+		return nil
+	}
+
+	stmt.Body = p.parseBlockStatement()
+
+	return stmt
+}
diff --git a/test-data/ltm.irule b/test-data/ltm.irule
new file mode 100644
index 0000000..f1a04a4
--- /dev/null
+++ b/test-data/ltm.irule
@@ -0,0 +1,9 @@
+ltm rule redirect_rule {
+  when HTTP_REQUEST {
+    if {[string tolower [HTTP::host]] eq "test.com" } {
+      node 192.168.191.5
+    }
+    elseif {[string tolower [HTTP::host]] eq "test2.com"}{
+      node 192.168.191.6
+    }}
+}
diff --git a/token/token.go b/token/token.go
index 5467856..0647aa7 100644
--- a/token/token.go
+++ b/token/token.go
@@ -169,6 +169,8 @@ const (
 	MATCH       = "match"
 	MATCHES     = "matches"
 	CLASS       = "class"
+	LTM         = "ltm"
+	RULE        = "rule"
 
 	// Additional control structures
 	SWITCH  = "switch"
@@ -209,6 +211,8 @@ var keywords = map[string]TokenType{
 	"class":       CLASS,
 	"foreach":     FOREACH,
 	"in":          IN,
+	"ltm":         LTM,
+	"rule":        RULE,
 
 	// F5 Event Contexts
 	"HTTP_REQUEST":        HTTP_REQUEST,