init.php

<?php
class Fever extends Plugin
{
    private $host;

    public function about()
    {
        return array(2.3,
            "Emulates the Fever API for Tiny Tiny RSS",
            "DigitalDJ, mestrode, murphy, eric-pierce, HenryQW");
    }

    public function init($host)
    {
        $this->host = $host;
        
        $host->add_hook($host::HOOK_PREFS_TAB, $this);
    }
    
    /* plugins/main/init.php hook_prefs_tab */

    public function hook_prefs_tab($args)
    {
        if ($args != "prefPrefs") {
            return;
        }


        print "<div dojoType=\"dijit.layout.AccordionPane\" 
			title=\"<i class='material-icons'>extension</i> ".__('Fever Emulation')."\">";


        print "<h3>" . __("Fever Emulation") . "</h3>";

        print "<p>" . __("Since the Fever API uses a different authentication mechanism to Tiny Tiny RSS, you must set a separate password to login. This password may be the same as your Tiny Tiny RSS password.") . "</p>";

        print "<p>" . __("Set a password to login with Fever:") . "</p>";
        
        print "<p><b>" . __("WARNING: The Fever API uses an UNSECURE unsalted MD5 hash. Consider the use of a disposable application-specific password and use HTTPS.") . "</b></p>";

        print "<form dojoType=\"dijit.form.Form\">";

        print "<script type=\"dojo/method\" event=\"onSubmit\" args=\"evt\">
            evt.preventDefault();
            if (this.validate()) {
                new Ajax.Request('backend.php', {
                    parameters: dojo.objectToQuery(this.getValues()),
                    onComplete: function(transport) {
                        Notify.msg(transport.responseText);
                    }
                });
                //this.reset();
            }
            </script>";
            
        print_hidden("op", "pluginhandler");
        print_hidden("method", "save");
        print_hidden("plugin", "fever");

        print "<input dojoType=\"dijit.form.ValidationTextBox\" required=\"1\" type=\"password\" name=\"password\" />";
        print_button("submit", __("Set Password"), "class='alt-primary'");
        print "</form>";

        print "<p>" . __("To login with the Fever API, set your server details in your favourite RSS application to: ") . get_self_url_prefix() . "/plugins/fever/" . "</p>";
        print "<p>" . __("Additional details can be found at ") . "<a href=\"http://www.feedafever.com/api\" target=\"_blank\">https://feedafever.com/api</a></p>";

        print "<p>" . __("Note: Due to the limitations of the API and some RSS clients (for example, Reeder on iOS), some features are unavailable: \"Special\" Feeds (Published / Tags / Labels / Fresh / Recent), Nested Categories (hierarchy is flattened)") . "</p>";

        print "</div>";
    }

    public function save()
    {
        if (isset($_POST["password"]) && isset($_SESSION["uid"])) {
            $sth = $this->pdo->prepare("SELECT login FROM ttrss_users WHERE id = ?");
            $sth->execute([clean($_SESSION["uid"])]);
            if ($line = $sth->fetch()) {
                $password = md5($line["login"] . ":" . $_POST["password"]);
                $this->host->set($this, "password", $password);
                echo __("Password saved.");
            }
        }
    }
    
    public function api_version()
    {
        return 2;
    }
}