<?php

class animal {
        private $years;
        private $bpd;
                        // Private - accessible ONLY from within the class
                        // So you can changes the internal structure
                        // later one - e.g. store in days (or years
                        // short of 37 ...

        protected $called;

                        // Protected - accessible within the class so that
                        // it can used internally within the class, and also
                        // from other classes that are derived from it, but
                        // not directly from outside the extended class tree

                        // Public - accessible from inside and out; needs to
                        // be maintained as a stable API in case customers of
                        // the class use it within their code

                        // Note - undeclared variables within an instance of an
                        // object in PHP default to being public, as do any which
                        // are declared with "var"

        function __construct($name,$age,$noise) {
                $this->called = $name;
                $this->years = $age;
                $this->bpd = $noise; }
        function getyears() {
                return $this->years; }
        function getbarks() {
                return $this->years * $this->bpd * 365; }
        function getname() {
                return $this->called; }

        function noisier($that) {
                $b1 = $this->getbarks();
                $b2 = $that->getbarks();
                if ($b1 < $b2) return $that;
                return $this;
                }

        function noisiest($choices) { // Static Method
                $sofar = $choices[0];
                foreach ($choices as $maybe) {
                        $sofar = $sofar->noisier($maybe);
                        }
                return $sofar;
                }

        function factory($about) { // Indirect constructor call
                $shards = explode(" ",$about);
                if ($shards[0] == "canine") {
                        return new dog($shards[1], $shards[2], $shards[3]);
                } else {
                        // etc
                }
        }
}

class dog extends animal { }

class sealion extends animal {
        function __construct($name,$age) {
                parent::__construct($name,$age,20); }}

class silentanimal extends animal {
        function __construct($name,$age) {
                parent::__construct($name,$age,0); }}

class giraffe extends silentanimal {}

class cat extends silentanimal {
        function getname() {
                return $this->called . " (a cat!)"; } }

# ------- main (test) code --------

/* The test code is off to one side like this so that it's only going to run when
the PHP file is called up, stand alone, from the command line. This way we can supply
and maintain a test harness / piece of example code in the same file that our
classes are maintained within. */

if ($_SERVER[SCRIPT_FILENAME] == __FILE__) {

// Setup a whole lot of objects in various ways for this test (in a live
// application, data would probably come from a file or database and be
// generated by a loop of calls to a factory method)

        $woof = new dog("Hamlet",8,2);
        $tall = new giraffe("Tiny",11);
        $yap = new dog("Gypsy",4,0.01);
        $pest = new dog("Chester",9,150);
        $miaow = new cat("Charlie",14);
        $pack = array($woof, $yap, $pest,
                animal::factory("canine Gnipper 1 4"),
                $geo = new sealion("George",6),
                new sealion("Ethel",8),
                $tall, $miaow);

        foreach ($pack as $mydaug) {
                $name = $mydaug->getname();
                $bsf = $mydaug->getbarks();
                print ("$name has barked $bsf times so far. ");
                print ("Age is " . $mydaug->getyears() . ".\n");
                }

// Noisier of $geo and $woof

/* 1. Compare in the app? Yuk, Yuk!
2. Write a function to compare? Yuk e.g. $bbb = noisier($geo,$woof);
3. Write a method to compare Yukfree ! e.g. $bbb = $geo->noisier($woof); */

        $bbb = $geo->noisier($woof);
        print ($bbb->getname() . " is a bit LOUDer\n");

        $ccc = animal::noisiest($pack);
        print ($ccc->getname() . " is a PAIN\n");

}

/*

munchkin:hound grahamellis$ php doggies.php
Hamlet has barked 5840 times so far. Age is 8.
Gypsy has barked 14.6 times so far. Age is 4.
Chester has barked 492750 times so far. Age is 9.
Gnipper has barked 1460 times so far. Age is 1.
George has barked 43800 times so far. Age is 6.
Ethel has barked 58400 times so far. Age is 8.
Tiny has barked 0 times so far. Age is 11.
Charlie (a cat!) has barked 0 times so far. Age is 14.
George is a bit LOUDer
Chester is a PAIN
munchkin:hound grahamellis$

*/

?>