But: — I recognize this as a Persian sentence typed in English letters using a Persian keyboard layout (so the English letters shown correspond to Persian keys pressed).

Let me break it down:

Decoding (reverse mapping from English letters to Persian keystrokes then reading Persian):

This string appears to be a keyboard shift cipher (e.g., each letter is shifted to a neighboring key on a standard Persian (Farsi) or English keyboard layout).

So: "danlwd fylm" = "فیلم دانلود" = film download? Check: d=د, a=ا, n=ن, l=ل, w=و, d=د = دانلود = download. fylm = فیلم = film.