Secure image display module / website

I am looking for an extension/mod to a current website. I need a module that will allow me to let my clients securely access a particular days photo shoot. ~~~~~~~~~~~~~~~Admin Side~~~~~~~~~~~~ I want the facility where I can upload (batch upload preferable) upto 500 images per shoot. Each image I would need automatically watermarking, as so the images are never in a state where they can be displayed without the watermark. Each shoot there could be upto 50 individual clients that need a different username/password combination to access. Each shoot can be differentiated and selected by the date i.e. 15th September 2015 Each Client on the shoot should be given a unique number / id of thier shoot and password to access the images...possibly emailed/SMS to them? Need the ability to create / modify & delete shoots and clients from shoots. Prefer it to integrate with the custom CMS backend. Admin has the ability already to manage content on the website, i.e. adding links and text to Pages. Would like an easy click button that would add an icon of a calendar and the Shoot date and prepopulate the desired area of the client side view failing that a copy/paste of code would suffice. ~~~~~~~~~~~~~~Client Side ~~~~~~~~~~~~~~ Client will click on the Dated Icon created when the shoot is created and saved and then be prompted for thier client shoot id and password. They are then taken to a nice light box / image scroller with thumbnails below so they can view thier shots (All images watermarked). Each image will have a reference number (this will be the name of the image minus the extension) that will need to be displayed as a title on the image or above it. Would like it to sit well in the current theme.