This is a famously beautiful arrangement of a Catalan folk song, by Romantic Era guitarist/composer Miguel Llobet. He wrote/arranged a set of 13 such songs, and this is probably the most famous one, frequently played as an encore.
One of the most lovely special touches in this piece is the use of harmonics for the echo-like repeat of the melody, which happens twice. In the video, This takes some practice! I gave you a close-up view of the right hand while it plays the harmonics section.