Convert HTML to VT100 terminal codes, to print colored and styled messages.

Create a directory for your application, cd to it, and issue:

composer require jeremiah-shaulov/html-to-vt100

<?php

require_once 'vendor/autoload.php';
use Vt100\Vt100;

// to output
echo Vt100::from_html('aaa<b style="color:magenta">BBB</b>ccc<br>');

// to error log
error_log(Vt100::from_html('aaa<b style="color:magenta">BBB</b>ccc<br>'));

CLI applications can echo messages to terminal. Web applications can write them to error log, or to a custom log file, and then view it with

less -r filename.log

The written file can be then converted to HTML and presented in browser:

<?php

require_once 'vendor/autoload.php';
use Vt100\Vt100;

$FILENAME = '/tmp/myapp.log';

// 1. Write some messages to file
file_put_contents($FILENAME, Vt100::from_html("<b>IMPORTANT</b> message<br>"));
file_put_contents($FILENAME, Vt100::from_html("<i style='color:blue'>Notice</i> message<br>"), FILE_APPEND);
file_put_contents($FILENAME, Vt100::from_html("<b style='color:yellow; background-color:black'>Warning</b> message<br>"), FILE_APPEND);

// 2. Read and present to browser
echo Vt100::to_html(file_get_contents($FILENAME));

Limited subset of HTML is supported:

• <br>
• <b>bold</b>
• <i>italic</i>
• <u>underlined</u>
• <blink>blink</blink> - Most modern terminals don't support this.
• <em>inverse fg/bg</em>
• <span style="color: magenta"> - Produces classic escape codes for black, red, green, yellow, blue, magenta, cyan and white. For other HTML colors - nonclassic.
• <span style="color: #AABBCC"> - Produces nonclassic escape codes.
• <span style="background-color: magenta">
• <span style="background-color: #AABBCC">
• <b>bold <span style="font-weight: normal">normal</span></b>
• <i>italic <span style="font-style: normal">normal</span></i>
• <u>underlined <span style="text-decoration: none">normal</span></u>
• <font color=blue>blue</font>

Namespace Vt100 contains one class called Vt100 with 2 static functions:

public static function from_html($str); // Converts HTML to VT100 escape codes.

public static function to_html($str); // Converts VT100 escape codes produced by from_html() back to HTML.