Chrome Plugin Development for WhatsApp Web

Hi,

I wound like to create a new Chrome plugin similar to the functionality we have in Joni, that enables sending WhatsApp messages from WhatsApp Web.
we should be able to download this plugin from chrome, so if there are any regulation in the code you need make sure it is being takening care of.

The plugin will communicate with external API to get the messages he needs to send.
the developer will only develop the call to the API. and get the message info.

If possible: the plugin will send every message we get into whatsApp web to webhook with the following
information: the message data, chat-id, from-number, to-number, chat-name, message, image, video.

the webhook url will have also contain a token at the end. the token will be given from the external api.
the plugin will need to make a request to the external API for token request. and use the token he gets from the api.
example:
https://www.domain-name/webhook/insert-message/1234-1234-1234-1234

please write me your developing plan on those requirements.
write me time estimation for the tasks.
write me your fixed price for this task.

i will only contact developers that posted what i am asking for.

Thank You
Ori