<?php
/**
 * PHP Command Line Tools
 *
 * This source file is subject to the MIT license that is bundled
 * with this package in the file LICENSE.
 *
 * @author    James Logsdon <[email protected]>
 * @copyright 2010 James Logsdom (http://girsbrain.org)
 * @license   http://www.opensource.org/licenses/mit-license.php The MIT License
 */

namespace cli;

/**
 * A more complex type of Notifier, `Progress` Notifiers always have a maxim
 * value and generally show some form of percent complete or estimated time
 * to completion along with the standard Notifier displays.
 *
 * @see cli\Notify
 */
abstract class Progress extends \cli\Notify {
    protected $_total = 0;

    /**
     * Instantiates a Progress Notifier.
     *
     * @param string  $msg       The text to display next to the Notifier.
     * @param int     $total     The total number of ticks we will be performing.
     * @param int     $interval  The interval in milliseconds between updates.
     * @see cli\Progress::setTotal()
     */
    public function __construct($msg, $total, $interval = 100) {
        parent::__construct($msg, $interval);
        $this->setTotal($total);
    }

    /**
     * Set the max increments for this progress notifier.
     *
     * @param int  $total  The total number of times this indicator should be `tick`ed.
     * @throws \InvalidArgumentException  Thrown if the `$total` is less than 0.
     */
    public function setTotal($total) {
        $this->_total = (int)$total;

        if ($this->_total < 0) {
            throw new \InvalidArgumentException('Maximum value out of range, must be positive.');
        }
    }

    /**
     * Reset the progress state so the same instance can be used in multiple loops.
     */
    public function reset($total = null) {
        parent::reset();

        if ($total) {
            $this->setTotal($total);
        }
    }

    /**
     * Behaves in a similar manner to `cli\Notify::current()`, but the output
     * is padded to match the length of `cli\Progress::total()`.
     *
     * @return string  The formatted and padded tick count.
     * @see cli\Progress::total()
     */
    public function current() {
        $size = strlen($this->total());
        return str_pad(parent::current(), $size);
    }

    /**
     * Returns the formatted total expected ticks.
     *
     * @return string  The formatted total ticks.
     */
    public function total() {
        return number_format($this->_total);
    }

    /**
     * Calculates the estimated total time for the tick count to reach the
     * total ticks given.
     *
     * @return int  The estimated total number of seconds for all ticks to be
     *              completed. This is not the estimated time left, but total.
     * @see cli\Notify::speed()
     * @see cli\Notify::elapsed()
     */
    public function estimated() {
        $speed = $this->speed();
        if (!$speed || !$this->elapsed()) {
            return 0;
        }

        $estimated = round($this->_total / $speed);
        return $estimated;
    }

    /**
     * Forces the current tick count to the total ticks given at instatiation
     * time before passing on to `cli\Notify::finish()`.
     */
    public function finish() {
        $this->_current = $this->_total;
        parent::finish();
    }

    /**
     * Increments are tick counter by the given amount. If no amount is provided,
     * the ticker is incremented by 1.
     *
     * @param int  $increment  The amount to increment by.
     */
    public function increment($increment = 1) {
        $this->_current = min($this->_total, $this->_current + $increment);
    }

    /**
     * Calculate the percentage completed.
     *
     * @return float  The percent completed.
     */
    public function percent() {
        if ($this->_total == 0) {
            return 1;
        }

        return ($this->_current / $this->_total);
    }
}