What's up with Greece?

After 6 months in power and numerous of negotiations, it seems that Tsipras has given in to the demands of the Troika. What happens next is still uncertain. Although the prime minister of Greece has given into their demands, he still has to get this deal swallowed by his communist (Syriza) party members. It's likely that this will be an uphill battle though. The whole existence of Syriza was based on ending austerity and setting the terms for future bailouts. He will have to convince his party, and the people of Greece, that the terms under the bailout agreement are far better than defaulting on their debt.
If the Greek parliament votes down the bailout terms, is where the economics comes in.
The first thing that would happen is the European Central Bank (ECB) will cut off all emergency liquidity needs to the Greek Banks. This will exacerbate the bank runs that are already happening and pretty much guarantee a financial crises.
To fight this problem the Greek government would have to rescue the banks themselves, but the Greek Central Bank cant print Euros. The only alternative would be to go back to the old Greek currency of Drachma and handle their own monetary policy.
If they're smart they won't do that. As JP Koening wrote here, switching back to the drachma suddenly would lead to hysteresis. Why would any firm company in Greece want to accept Greek drachmas, that would certainly be devalued by the hot potato money printing the government would need to do to pay their obligations, when they could have strong Euros backed by credible institutions.
What comes next is beyond anybody knowledge, but the combination of rampant inflation, two currencies circulating, and high interest rates that greece had with the drachma would be a nightmare for anyone living there.
The deal reached is far from perfect, and may even hurt the Greek economy. But it's a trade off that might be well worth it in the long run.