A 35-year-Old man presents with daily headache. He describes two attacks per day over the last 3 weeks. Each attack lasts about an hour and awakens him from sleep. The patient has noticed associated tearingand reddening of the right eye as well as nasal stuffness. The pain's deep, excruciating, and limiting to the right side of the head. The neurological examination is normal. What is the most likely diagnosis?

Harrison's principles of internal medicine 17th edition . *Cluster headache is associated with ipsilateral symptoms of cranial parasympathetic autonomic activation:conjunctival injection or lacrimation ,rhinorrhea or nasal congestion ,cranial sympathetic dysfunction such as ptosis *Pain is deep,retroorbital ,excruciating in intensity nonfluctuating and explosive *Atleast one of the daily attack of pain recurs at about the same hour each day for the duration of a cluster bout. *Onset is nocturnal in about 50%patients and men are effected three times more than women . Ref Harrison20th edition pg 2245