electrons.php

<?php
// electrons and stuff go here
$electrons = [
	'H'  => ['block' => 's'],
	'He' => ['block' => 's'],
	'Li' => ['block' => 's'],
	'Be' => ['block' => 's'],
	'B'  => ['block' => 'p'],
	'C'  => ['block' => 'p'],
	'N'  => ['block' => 'p'],
	'O'  => ['block' => 'p'],
	'F'  => ['block' => 'p'],
	'Ne' => ['block' => 'p'],
	'Na' => ['block' => 's'], 
	'Mg' => ['block' => 's'],
	'Al' => ['block' => 'p'],
	'Si' => ['block' => 'p'],
	'P'  => ['block' => 'p'],
	'S'  => ['block' => 'p'],
	'Cl' => ['block' => 'p'],
	'Ar' => ['block' => 'p'],
	'K'  => ['block' => 's'],
	'Ca' => ['block' => 's'],
	'Sc' => ['block' => 'd'],
	'Ti' => ['block' => 'd'],
	'V'  => ['block' => 'd'],
	'Cr' => ['block' => 'd'],
	'Mn' => ['block' => 'd'],
	'Fe' => ['block' => 'd'],
	'Co' => ['block' => 'd'],
	'Ni' => ['block' => 'd'],
	'Cu' => ['block' => 'd'],
	'Zn' => ['block' => 'd'],
	'Ga' => ['block' => 'p'],
	'Ge' => ['block' => 'p'],
	'As' => ['block' => 'p'],
	'Se' => ['block' => 'p'],
	'Br' => ['block' => 'p'],
	'Kr' => ['block' => 'p'],
	'Rb' => ['block' => 's'],
	'Sr' => ['block' => 's'],
	'Y'  => ['block' => 'd'],
	'Zr' => ['block' => 'd'],
	'Nb' => ['block' => 'd'],
	'Mo' => ['block' => 'd'],
	'Tc' => ['block' => 'd'],
	'Ru' => ['block' => 'd'],
	'Rh' => ['block' => 'd'], 
	'Pd' => ['block' => 'd'],
	'Ag' => ['block' => 'd'],
	'Cd' => ['block' => 'd'],
	'In' => ['block' => 'p'],
	'Sn' => ['block' => 'p'],
	'Sb' => ['block' => 'p'],
	'Te' => ['block' => 'p'],
	'I'  => ['block' => 'p'],
	'Xe' => ['block' => 'p'],
	'Cs' => ['block' => 's'],
	'Ba' => ['block' => 's'],
	'La' => ['block' => 'f'],
	'Ce' => ['block' => 'f'],
	'Pr' => ['block' => 'f'],
	'Nd' => ['block' => 'f'],
	'Pm' => ['block' => 'f'],
	'Sm' => ['block' => 'f'],
	'Eu' => ['block' => 'f'],
	'Gd' => ['block' => 'f'],
	'Tb' => ['block' => 'f'],
	'Dy' => ['block' => 'f'],
	'Ho' => ['block' => 'f'],
	'Er' => ['block' => 'f'],
	'Tm' => ['block' => 'f'],
	'Yb' => ['block' => 'f'],
	'Lu' => ['block' => 'd'],
	'Hf' => ['block' => 'd'],
	'Ta' => ['block' => 'd'],
	'W'  => ['block' => 'd'],
	'Re' => ['block' => 'd'],
	'Os' => ['block' => 'd'],
	'Ir' => ['block' => 'd'],
	'Pt' => ['block' => 'd'],
	'Au' => ['block' => 'd'],
	'Hg' => ['block' => 'd'],
	'Tl' => ['block' => 'p'],
	'Pb' => ['block' => 'p'],
	'Bi' => ['block' => 'p'],
	'Po' => ['block' => 'p'],
	'At' => ['block' => 'p'],
	'Rn' => ['block' => 'p'],
	'Fr' => ['block' => 's'],
	'Ra' => ['block' => 's'],
	'Ac' => ['block' => 'f'],
	'Th' => ['block' => 'f'],
	'Pa' => ['block' => 'f'],
	'U'  => ['block' => 'f'],
	'Np' => ['block' => 'f'],
	'Pu' => ['block' => 'f'],
	'Am' => ['block' => 'f'],
	'Cm' => ['block' => 'f'],
	'Bk' => ['block' => 'f'],
	'Cf' => ['block' => 'f'],
	'Es' => ['block' => 'f'],
	'Fm' => ['block' => 'f'],
	'Md' => ['block' => 'f'],
	'No' => ['block' => 'f'],
	'Lr' => ['block' => 'd'],
	'Rf' => ['block' => 'd'],
	'Db' => ['block' => 'd'],
	'Sg' => ['block' => 'd'],
	'Bh' => ['block' => 'd'],
	'Hs' => ['block' => 'd'],
	'Mt' => ['block' => 'd'],
	'Ds' => ['block' => 'd'],
	'Rg' => ['block' => 'd'],
	'Cn' => ['block' => 'd'],
	'Nh' => ['block' => 'p'],
	'Fl'  => ['block' => 'p'],
	'Mc' => ['block' => 'p'],
	'Lv'  => ['block' => 'p'],
	'Ts' => ['block' => 'p'],
	'Og' => ['block' => 'p']
];

function electron_config($element_number, $shortened = false) {
	// Check for exceptions
	$exceptions = [
		24 => '1s2 2s2 2p6 3s2 3p6 4s1 3d5',
		29 => '1s2 2s2 2p6 3s2 3p6 4s1 3d10',
		41 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d4',
		42 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d5',
		44 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d7',
		45 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d8',
		46 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 4d10',
		47 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d10',
		57 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 5d1',
		58 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f1 5d1',
		64 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f7 5d1',
		78 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s1 4f14 5d9',
		79 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s1 4f14 5d10',
		89 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 6d1',
		90 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 6d2',
		91 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f2 6d1',
		92 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f3 6d1',
		93 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f4 6d1',
		96 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f7 6d1',
		103 => '1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 7p1'
	];
	if(array_key_exists($element_number, $exceptions)) {
		$notation_exception = $exceptions[$element_number];
	}
	
	$orbital_capacity = [
		's' => 2,
		'p' => 6,
		'd' => 10,
		'f' => 14
	];
	
	$notation_order = [
		'1s', '2s', '2p', '3s', '3p',
		'4s', '3d', '4p', '5s',	'4d',
		'5p', '6s', '4f', '5d', '6p',
		'7s', '5f', '6d', '7p', '8s',
	];
	
	$electrons = $element_number;
	$notation = '';
	
	foreach($notation_order as $orbital) {
		$orbital_type = substr($orbital, -1);
		$orbital_value = 0;
		while($electrons > 0 && $orbital_value < $orbital_capacity[$orbital_type]) {
			$orbital_value++;
			$electrons--;
		}
		$notation .= $orbital . $orbital_value;
		if($electrons === 0) {
			break;
		} else {
			$notation .= ' ';
		}
	}
	
	if(isset($notation_exception)) {
		$notation = $notation_exception;
	}
	
	// Optionally shorten the notation
	$noble_gases = [
		'He' => 2,
		'Ne' => 10,
		'Ar' => 18,
		'Kr' => 36,
		'Xe' => 54,
		'Rn' => 86,
	];
	
	if($shortened) {
		foreach(array_reverse($noble_gases) as $key => $gas) {
			if($element_number > $gas) {
				$replace_notation = electron_config($gas, false, 0);
				$shortened_notation = '[' . $key . ']';
				return str_replace($replace_notation, $shortened_notation, $notation);
			}
		}
	}
	
	return $notation;
}