There are two directories in which teieditor code can be found.

/var/www/drupal/sites/all/modules/teieditor: This directory contains 
that drupal module.

Files:

    teieditor.module:
    This file defines the permissions for the module as well as how to
    render the page and deal with ajax posts. There are two ajax posts
    the module deals with 'getTEI' which gets a TEI document  from
    fedora specified by the pid in the post url and returns it to the
    Javascript via a ajax post, and 'save' which receives the edited
    document from the javascript and validates it before saving the
    document back to fedora, it will not save the document if it doesn't
    pass validation.

    utils.php:
    This php file is filled with helper functions that allow
    teieditor.module to interact with fedora, perform riseachs, ect.
    There are functions within this file that rely on  the islandora
    module, if the islandora module was to change in some significant
    way it could break the editor.

    tei.js:
    Defines a the tei schema within javascript, this file defines the
    tei elements and attributes, and how they are supposed to work.
    There is also some work here on the tei model classes but I had to
    discard that work when I discovered the TEI documents in fedora were
    not valid by the model class standards, so there is a bit of a hack
    to keep users from inserting <forename> anywhere except within a
    <persName> tag.

    teieditor.js:
    Renders and controls the functionality of the editor, such as what
    the buttons do, it depends of the definitions within tei.js to
    function correctly. The nice thing about the seperation of the
    schema and editor is that you can add new tei elements or attributes
    to tei.js, and the editor will work perfectly well with the new
    tags, and elements.

    teieditor.css:
    Style for the editor.

    tei.css:
    Style for the tei elements, just the color backgrounds behind the
    tags really.

    teilite.rng:
    Used to validate the TEI document before saving.

    teieditor.info:
    Exposes the module to drupal, defines the name of the module who
    owns it excetera.

    Jquery folder: jquery 3.2 is kept in here, I don't use drupals
    version of jquery as its 3.0 or 3.1 and doesn't support some of the
    features the editor uses.

/usr/local/fedora/tomcat/webapps/teieditor: This directory contains the 
iframe needed to render the djatoka viewer, also included in this is a 
separate instance openlayers 2.7 and Jquery 3.2.

Files:

    teieditor_iframe.html:
    The html file that gets loaded into the editors iframe, this is
    where the page image gets rendered.

    jQuery 3.2:  folder contains  jQuery.

    Open Layers 2.7: folder contains open layers.