From 490ae37c6deba83adadcab58f3c37756703d3ab7 Mon Sep 17 00:00:00 2001
From: Hein <hein@bitechsystems.co.za>
Date: Wed, 10 Dec 2025 11:48:03 +0200
Subject: [PATCH] Fixed bugs in extractTableAndColumn

---
 pkg/common/sql_helpers.go      | 40 ++++++++++++++++++++++++++-
 pkg/common/sql_helpers_test.go | 50 ++++++++++++++++++++++++++++++++++
 2 files changed, 89 insertions(+), 1 deletion(-)

diff --git a/pkg/common/sql_helpers.go b/pkg/common/sql_helpers.go
index e110750..8d62168 100644
--- a/pkg/common/sql_helpers.go
+++ b/pkg/common/sql_helpers.go
@@ -430,7 +430,45 @@ func extractTableAndColumn(cond string) (table string, column string) {
 	// Remove any quotes
 	columnRef = strings.Trim(columnRef, "`\"'")
 
-	// Check if it contains a dot (qualified reference)
+	// Check if there's a function call (contains opening parenthesis)
+	openParenIdx := strings.Index(columnRef, "(")
+
+	if openParenIdx >= 0 {
+		// There's a function call - find the FIRST dot after the opening paren
+		// This handles cases like: ifblnk(users.status, orders.status) - extracts users.status
+		dotIdx := strings.Index(columnRef[openParenIdx:], ".")
+		if dotIdx > 0 {
+			dotIdx += openParenIdx // Adjust to absolute position
+
+			// Extract table name (between paren and dot)
+			// Find the last opening paren before this dot
+			lastOpenParen := strings.LastIndex(columnRef[:dotIdx], "(")
+			table = columnRef[lastOpenParen+1 : dotIdx]
+
+			// Find the column name - it ends at comma, closing paren, whitespace, or end of string
+			columnStart := dotIdx + 1
+			columnEnd := len(columnRef)
+
+			for i := columnStart; i < len(columnRef); i++ {
+				ch := columnRef[i]
+				if ch == ',' || ch == ')' || ch == ' ' || ch == '\t' {
+					columnEnd = i
+					break
+				}
+			}
+
+			column = columnRef[columnStart:columnEnd]
+
+			// Remove quotes from table and column if present
+			table = strings.Trim(table, "`\"'")
+			column = strings.Trim(column, "`\"'")
+
+			return table, column
+		}
+	}
+
+	// No function call - check if it contains a dot (qualified reference)
+	// Use LastIndex to handle schema.table.column properly
 	if dotIdx := strings.LastIndex(columnRef, "."); dotIdx > 0 {
 		table = columnRef[:dotIdx]
 		column = columnRef[dotIdx+1:]
diff --git a/pkg/common/sql_helpers_test.go b/pkg/common/sql_helpers_test.go
index 0add7f1..2874c19 100644
--- a/pkg/common/sql_helpers_test.go
+++ b/pkg/common/sql_helpers_test.go
@@ -286,6 +286,48 @@ func TestExtractTableAndColumn(t *testing.T) {
 			expectedTable: "",
 			expectedCol:   "",
 		},
+		{
+			name:          "function call with table.column - ifblnk",
+			input:         "ifblnk(users.status,0) in (1,2,3,4)",
+			expectedTable: "users",
+			expectedCol:   "status",
+		},
+		{
+			name:          "function call with table.column - coalesce",
+			input:         "coalesce(users.age, 0) = 25",
+			expectedTable: "users",
+			expectedCol:   "age",
+		},
+		{
+			name:          "nested function calls",
+			input:         "upper(trim(users.name)) = 'JOHN'",
+			expectedTable: "users",
+			expectedCol:   "name",
+		},
+		{
+			name:          "function with multiple args and table.column",
+			input:         "substring(users.email, 1, 5) = 'admin'",
+			expectedTable: "users",
+			expectedCol:   "email",
+		},
+		{
+			name:          "cast function with table.column",
+			input:         "cast(orders.total as decimal) > 100",
+			expectedTable: "orders",
+			expectedCol:   "total",
+		},
+		{
+			name:          "complex nested functions",
+			input:         "coalesce(nullif(users.status, ''), 'default') = 'active'",
+			expectedTable: "users",
+			expectedCol:   "status",
+		},
+		{
+			name:          "function with multiple table.column refs (extracts first)",
+			input:         "greatest(users.created_at, users.updated_at) > '2024-01-01'",
+			expectedTable: "users",
+			expectedCol:   "created_at",
+		},
 	}
 
 	for _, tt := range tests {
@@ -352,6 +394,14 @@ func TestSanitizeWhereClauseWithPreloads(t *testing.T) {
 			},
 			expected: "users.status = 'active' AND Department.name = 'Engineering'",
 		},
+
+		{
+			name:      "Function Call with correct table prefix - unchanged",
+			where:     "ifblnk(users.status,0) in (1,2,3,4)",
+			tableName: "users",
+			options:   nil,
+			expected:  "ifblnk(users.status,0) in (1,2,3,4)",
+		},
 		{
 			name:      "no options provided - works as before",
 			where:     "wrong_table.status = 'active'",