cannot open photoshop file

A quick Google search "Photoshop unexpected end-of-file encountered" turned up several possible solutions from special software to trying to open the file in Illustrator. Bottom line: you have a damaged file and without a backup or Mac's Time Machine the chances of recovering the file are slim and the causes vary. I know the following advice is after the fact but in the future consider, as you work on file,  now and then save the file with a number sequence, such as: filename_1, filename_2, etc.

Hi laxmish.shetty,

You may try resetting the Photoshop preferences back to defaults and check if that helps.

Refer: Preferences in Photoshop

Regards,

Mohit