A 36-year-old patient complains of suffocation attacks with predominantly problematic exhalation. The attacks occur up to 2-3 times a day and can be relieved by inhalation of β2-adrenomimetics. This condition lasts for 10 years already. Objectively, the chest is expanded, percussion detects a bandbox resonance over the lungs, auscultation detects harsh respiration with prolonged exhalation. Laboratory analysis of sputum detects numerous eosinophils, Charcot-Leyden crystals, and Curschmann spirals. What is the provisional diagnosis in this case?