1 files changed, 43 insertions, 0 deletions
diff --git a/internal/llm/logging.go b/internal/llm/logging.go
new file mode 100644
index 0000000..a6a6e51
--- /dev/null
+++ b/internal/llm/logging.go
@@ -0,0 +1,43 @@
+package llm
+
+import (
+    "fmt"
+    "log"
+)
+
+// ANSI color utilities shared across LLM providers.
+const (
+    AnsiBgBlack = "\x1b[40m"
+    AnsiGrey    = "\x1b[90m"
+    AnsiCyan    = "\x1b[36m"
+    AnsiGreen   = "\x1b[32m"
+    AnsiRed     = "\x1b[31m"
+    AnsiReset   = "\x1b[0m"
+)
+
+// AnsiBase is the default style: black background + grey foreground.
+const AnsiBase = AnsiBgBlack + AnsiGrey
+
+// LogPrintf wraps a formatted message with a base style and prints with a prefix.
+func LogPrintf(logger *log.Logger, prefix, format string, args ...any) {
+    if logger == nil {
+        return
+    }
+    msg := fmt.Sprintf(format, args...)
+    logger.Print(AnsiBase + prefix + msg + AnsiReset)
+}
+
+// Logging configuration for previews (shared)
+var logPreviewLimit int // 0 means unlimited
+
+// SetLogPreviewLimit sets the maximum number of characters to log for
+// request/response previews. Set to 0 for unlimited.
+func SetLogPreviewLimit(n int) { logPreviewLimit = n }
+
+func previewForLog(s string) string {
+    if logPreviewLimit > 0 {
+        return trimPreview(s, logPreviewLimit)
+    }
+    return s
+}
+