The stock market has been rough in 2022. The S&P 500 (^GSPC -0.22%) and Nasdaq Composite (^IXIC -0.52%) market indexes had posted gains of more than 20% in 2021. Those gains were erased in the first half of this year, however, turning into a 14% rout for the more volatile Nasdaq index:

^SPX Chart

^SPX data by YCharts.

This adverse market action makes many investors nervous. Nobody wants to catch a falling knife, after all. However, the broad market retreat also uncovers fantastic buying opportunities when high-quality companies and struggling also-rans are tagged with the same massive discounts.

That's where you'll find media-streaming technology expert Roku (ROKU 1.91%) right now. Market makers have concluded that Roku's best days are behind it, resulting in a 60% share-price drop in 2022 and a 79% discount on a 52-week basis. But Roku's long-term growth story is just getting started, and this senseless correction is actually a great buying opportunity.

A massive (and growing) target market

Roku founder and CEO Anthony Wood likes to set ambitious goals. In the long run, he expects all TV viewing to eventually move from cable, satellite, and broadcast channels to digital-streaming services. Where viewers are going, advertising dollars will follow.

His company is already a leading provider of user-friendly streaming solutions in North America, with the longest track record in the industry. That pole-position market share is expanding, quarter by quarter. Everyone else is playing catch-up.

The company's primary target market is enormous, and Roku has a head start. And that's not all: Roku's international presence is minuscule so far, leaving a metric ton of unexplored market space with roughly 5.5 billion TV viewers worldwide.

Remember, all of these TV watchers should eventually move over to the media-streaming market. Furthermore, the company is expanding its product portfolio to include its own brand of original content, video-based advertising services, and more.

Roku's stock shouldn't be this cheap

ROKU Revenue (TTM) Chart

ROKU Revenue (TTM) data by YCharts.

Given Roku's tremendous market ambition and soaring revenue growth, I see a market-crunching opportunity in the suddenly affordable share price. The company is already generating robust free cash flow, and the balance sheet is pristine, with $2.2 billion of cash reserves and just $89 million in long-term debt. This rock-solid financial platform will help Roku achieve those lofty growth targets as the media-streaming industry evolves.

You can get all of this at a fraction of the share price seen a year ago. So in my eyes, Roku is the closest thing to a sure long-term winner, and it's kind of silly not to take advantage of this buying opportunity right now.