Bronchitis: This is the most likely diagnosis given the patient's symptoms of cough, fever, and recent onset of hemoptysis (streaks of blood). Bronchitis, especially in a smoker, can lead to inflammation and irritation of the bronchial tubes, which may cause bleeding.

Bronchiectasis: This condition involves the permanent enlargement of parts of the airways and can be a complication of chronic bronchitis or other infections. It could explain the patient's symptoms, especially if there's a history of recurrent infections or chronic cough.
Lung Cancer: Although less likely given the acute presentation, lung cancer is a significant concern in smokers and can cause cough, fever, and hemoptysis. However, the onset of symptoms over just a few days is less typical for cancer.

Pulmonary Embolism: This is a potentially life-threatening condition that can cause sudden onset of symptoms including cough, fever, and hemoptysis. Although less common, it's crucial to consider, especially in patients with risk factors for thromboembolism.
Tuberculosis (TB): TB can cause chronic cough, fever, and hemoptysis. It's essential to consider, especially if the patient has been exposed to TB or has risk factors such as immunocompromised status.

Goodpasture Syndrome: A rare autoimmune disease that can cause pulmonary hemorrhage, leading to hemoptysis, and renal failure. It's less likely but should be considered if other diagnoses are ruled out and there are suggestive findings like renal involvement.
Wegener's Granulomatosis (Granulomatosis with Polyangiitis): Another rare autoimmune condition that can affect the lungs and kidneys, causing symptoms similar to those presented. It's a diagnosis of exclusion and would require specific diagnostic testing.