Reading SMS via website

It is necessary to display the last message received by SMS on the site.
To do this, we will use a virtual number and read incoming SMS through the API.

General concept:
Using php and JavaScript to make a button on the site "I sent the code"
A modal window opens and counts down for 20 seconds and the "Check Code" button appears
when you click check if there are new messages, if there are, check that the message begins with the word [Apple] and then display it to the user.
If not, we display the message "The message has not yet been received, wait for 10,9,8...." and again allow you to check through the button.
It is also important to make sessions in case 2 people try at the same time. That is, if someone has already clicked the "check code" button, then the next one will not be able to press it and will receive the message "Someone is already receiving the code, try in 10 minutes"


Modal windows need to be created using sweetalert2.github.io, there is just a window with a timer and everything else.
API to read SMS will use this https://zadarma.com/ru/support/api/#other_methods_sms

The main site uses a smarty template engine and php (most likely Slim Framework)

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