Is it a good idea to invest in a crashed currency in hopes for a long term rebound?

With the current state of the Iranian Rial, and government protest, I was thinking about a possibility of a better future in Iran and what that would look like economicly.

Assuming the country does turn democratic, at least some semblance of it, and rejoins the global market, doesnt Iran have everything a nation could need to become economically well off? Natural recourses, large working age population, situated in the best location or act as a land route for trade and pipelines. Im wondering if something similar to how Germany rebound post great depression.

So if I do invest in the iranian in the Iranian Rial and the economy rebounds (and I am thinking 10 – 20 years not just overnight) wouldnt that be a great overtunity? How does a currency rebound? What happens if they switch to a new currency? Would it just be better to invest into Iranian business after governmental change? (Assuming it happens)