A 36-year-old G3 P1 pregnant woman at 34 weeks gestation presents with sudden-onset vaginal bleeding, severe abdominal pain, and uterine tenderness. Her history is significant for preeclampsia in her first pregnancy and chronic hypertension. She smokes one pack of cigarettes a day and uses cocaine occasionally. On examination, the uterus is firm and rigid on examination, and fetal heart rate monitoring shows distress. What is the most likely diagnosis?