<?php

/**
 * Declare an enumeration.
 * It can also contain an optional 'string' or 'int' value. This is called backed Enum.
 * Backed enums (if used) should match the following criteria:
 * - Declare the scalar type, whether string or int, in the Enum declaration.
 * - All cases have values.
 * - All cases contain the same scalar type, whether string or int.
 * - Each case has a unique value.
 */
enum UserRole: string {
    case ADMIN    = '1';
    case GUEST    = '2';
    case WRITER   = '3';
    case EDITOR   = '4';
}

/**
 * You can access a case by using
 * the '::' scope resolution operator.
 * And, to get the name of the enum case, you
 * can use the '->' followed by the attribute 'name'.
 */
echo UserRole::WRITER->name;

/**
 * To get the value of the enum case, you can
 * use the '->' followed by the attribute 'value'.
 */
echo UserRole::WRITER->value;

?>

<?php

/**
 * Initialize the Fiber.
 */
$fiber = new Fiber(function(): void {
    /**
     * Print some message from inside the Fiber.
     * Before the Fiber gets suspended.
     */
    echo "Welcome to Fiber!\n";
    /**
     * Suspend the Fiber.
     */
    Fiber::suspend();
    /**
     * Print some message from inside the Fiber.
     * After the Fiber gets resumed.
     */
    echo "Welcome back to Fiber!\n";
});

/**
 * Print a message before starting a Fiber.
 */
echo "Starting a Fiber\n";
/**
 * Start the Fiber.
 */
$fiber->start();
/**
 * Fiber has been suspened from the inside.
 * Print some message, and then resume the Fiber.
 */
echo "Fiber has been suspended\n";
echo "Resuming the Fiber\n";
/**
 * Resume the Fiber.
 */
$fiber->resume();
/**
 * End of the example.
 */
echo "Fiber completed execution\n";

?>

<?php

/**
 * Route Class
 */
class Route {

    /**
     * Constructor of the class
     * @return void
     */
    public function __construct() {

    }

    /**
     * Redirect To a Page
     * This function redirects to an URL specified by the user.
     * @method redirect()
     * @param string $url
     * @param integer $httpCode
     * @author Tara Prasad Routray <someemailaddress@example.com>
     * @access public
     * @return never
     */
    public static function redirect($url, $httpCode = 301): never {
        /**
         * Redirect to the URL specified.
         */
        header("Location: {$url}", true, $httpCode);
        die;
    }
}

Route::redirect('https://www.google.com');

?>

<?php

/**
 * User Class
 */
class User {
    /**
     * Declare a variable with readonly property.
     * @var $authUserID
     * @access public
     */
    public readonly int $authUserID;
    /**
     * Constructor of the class.
     * @param integer $userID
     * @return void
     */
    public function __construct($userID) {
        /**
         * Change the value of the property as specified.
         * Updating the value of readonly properties are
         * allowed only through the constructor.
         */
        $this->authUserID = $userID;
    }
    /**
     * Update Auth User ID
     * This function tries to update the readonly property (which is not allowed).
     * @method updateAuthUserID()
     * @param integer $userID
     * @author Tara Prasad Routray <someemailaddress@example.com>
     * @access public
     * @return void
     */
    public function updateAuthUserID($userID) {
        /**
         * Change the value of the property as specified.
         * Executing this function will throw the following error;
         * PHP Fatal error:  Uncaught Error: Cannot modify readonly property User::$authUserID
         */
        $this->authUserID = $userID;
    }
}
/**
 * Initialize the class and update the value of the readonly property.
 */
$user = new User(30);
/**
 * Print the readonly property value.
 * This will print 30.
 */
echo $user->authUserID;
/**
 * Call another function inside the class and try to update the class property.
 */
$user->updateAuthUserID(50);
/**
 * Print the readonly property value.
 */
echo $user->authUserID;

?>

<?php

/**
 * UserRole Class
 */
class UserRole {
    /**
     * Declare a final class constant with a value.
     */
    final public const ADMIN = '1';
}

/**
 * User Class extending the UserRole Class
 */
class User extends UserRole {
    /**
     * Declare another constant with the same name
     * as of the parent class to override the value.
     * 
     * Note: Overriding the value will throw the following error:
     * PHP Fatal error:  User::ADMIN cannot override final constant UserRole::ADMIN
     */
    public const ADMIN = '2';
}

?>

<?php

/**
 * Returns true for empty array.
 */
array_is_list([]);
/**
 * Returns true for sequential set of keys.
 */
array_is_list([1, 2, 3]);
/**
 * Returns true as the first key is zero, and keys are in sequential order.
 * It is same as [0 => 'apple', 1 => 2, 2 => 3]
 */
array_is_list(['apple', 2, 3]);
/**
 * Returns true as the first key is zero, and keys are in sequential order.
 * It is same as [0 => 'apple', 1 => 'scissor']
 */
array_is_list(['apple', 'orange']);
/**
 * Returns true as the first key is zero, and keys are in sequential order.
 * It is same as [0 => 'apple', 1 => 'scissor']
 */
array_is_list([0 => 'apple', 'orange']);
/**
 * Returns true as the first key is zero, and keys are in sequential order.
 */
array_is_list([0 => 'rock', 1 => 'scissor']);

?>

<?php

/**
 * Returns false as the first key does not start from zero.
 */
array_is_list([1 => 'apple', 'orange']);
/**
 * Returns false as the first key does not start from zero.
 */
array_is_list([1 => 'apple', 0 => 'orange']);
/**
 * Returns false as all keys are not integer.
 */
array_is_list([0 => 'apple', 'fruit' => 'orange']);
/**
 * Returns false as the keys are not in sequential order.
 */
array_is_list([0 => 'apple', 2 => 'orange']); 

?>

<?php

/**
 * Declare a variable and assign a filename.
 */
$fileName = 'notes.txt';
/**
 * Create the file with read and write permission.
 */
$file = fopen($fileName, 'w+');
/**
 * Add some text into the file.
 */
fwrite($file, 'Paragraph 1');
/**
 * Add a line break into the file.
 */
fwrite($file, "\r\n");
/**
 * Add some more text into the file.
 */
fwrite($file, 'Paragraph 2');
/**
 * You can use both the fsync() or fdatasync() functions 
 * to commit changs to disk.
 */
fsync($file); // or fdatasync($file).
/**
 * Close the open file pointer.
 */
fclose($file);

?>

<?php

/**
 * Declare an array
 */
$fruits1 = ['Jonathan Apples', 'Sapote'];
/**
 * Declare another array
 */
$fruits2 = ['Pomelo', 'Jackfruit'];
/**
 * Merge above two arrays using array unpacking.
 */
$unpackedFruits = [...$fruits1, ...$fruits2, ...['Red Delicious']];
/**
 * Print the above unpacked array.
 * This will print:
 * array(5) {
 * [0]=>
 * string(15) "Jonathan Apples"
 * [1]=>
 * string(6) "Sapote"
 * [2]=>
 * string(6) "Pomelo"
 * [3]=>
 * string(9) "Jackfruit"
 * [4]=>
 * string(13) "Red Delicious"
 * }
 */
var_dump($unpackedFruits);

?>

<?php

/**
 * Check if the user has submitted the form.
 */
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    /**
     * Print the $_FILES global variable. This will display the following:
     * array(1) {
     *   ["myfiles"]=> array(6) {
     *     ["name"]=> array(2) {
     *       [0]=> string(9) "image.png"
     *       [1]=> string(9) "image.png"
     *     }
     *     ["full_path"]=> array(2) {
     *       [0]=> string(25) "folder1/folder2/image.png"
     *       [1]=> string(25) "folder3/folder4/image.png"
     *     }
     *     ["tmp_name"]=> array(2) {
     *       [0]=> string(14) "/tmp/phpV1J3EM"
     *       [1]=> string(14) "/tmp/phpzBmAkT"
     *     }
     *     // ... + error, type, size
     *   }
     * }
     */
    var_dump($_FILES);
}

?>

<form action="" method="POST" enctype="multipart/form-data">
    <input name="myfiles[]" type="file" webkitdirectory multiple />
    <button type="submit">Submit</button>
</form>

<?php

/**
 * Define a default date format.
 */
$skeleton = "YYYY-MM-dd";
/**
 * Parse a time string (for today) according to a specified format.
 */
$today = \DateTimeImmutable::createFromFormat('Y-m-d', date('Y-m-d'));
/**
 * ===========================
 * PRINTING DATE IN USA FORMAT
 * ===========================
 * Initiate an instance for the IntlDatePatternGenerator class
 * and provide the locale information.
 * In the below example, I've used locale: en_US.
 */ 
$intlDatePatternGenerator = new \IntlDatePatternGenerator("en_US");
/**
 * Get the correct date format for the locale: en_US.
 * Following function "getBestPattern" will return:
 * MM/dd/YYYY
 */
$enUSDatePattern = $intlDatePatternGenerator->getBestPattern($skeleton);
/**
 * Use the "formatObject" function of IntlDateFormatter to print as per specified pattern.
 * This will print the following:
 * Date in en-US: 12/03/2021
 */
echo "Date in en-US: ". \IntlDateFormatter::formatObject($today, $enUSDatePattern, "en_US"). "\n";

/**
 * =============================
 * PRINTING DATE IN INDIA FORMAT
 * =============================
 * Initiate an instance for the IntlDatePatternGenerator class
 * and provide the locale information.
 * In the below example, I've used locale: en_IN.
 */
$intlDatePatternGenerator = new \IntlDatePatternGenerator("en_IN");
/**
 * Get the correct date format for the locale: en_IN.
 * Following function "getBestPattern" will return:
 * dd/MM/YYYY
 */
$enINDatePattern = $intlDatePatternGenerator->getBestPattern($skeleton);
/**
 * Use the "formatObject" function of IntlDateFormatter to print as per specified pattern.
 * This will print the following:
 * Date in en-IN: 03/12/2021
 */
echo "Date in en-IN: ". \IntlDateFormatter::formatObject($today, $enINDatePattern, "en_IN"). "\n";

?>