<?php
/**
 * @link http://www.yiiframework.com/
 * @copyright Copyright (c) 2008 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

namespace yii\debug\models\timeline;

use yii\base\Object;
use yii\debug\panels\TimelinePanel;

/**
 * Svg is used to draw a graph using SVG
 *
 * @author Dmitriy Bashkarev <dmitriy@bashkarev.com>
 * @since 2.0.8
 */
class Svg extends Object
{
    /**
     * @var int Max X coordinate
     */
    public $x = 1920;
    /**
     * @var int Max Y coordinate
     */
    public $y = 40;
    /**
     * @var string Stroke color
     */
    public $stroke = '#1e6823';
    /**
     * @var array Listen messages panels
     */
    public $listenMessages = ['log', 'profiling'];
    /**
     * @var array Color indicators svg graph.
     */
    public $gradient = [
        10 => '#d6e685',
        60 => '#8cc665',
        90 => '#44a340',
        100 => '#1e6823'
    ];
    /**
     * @var string Svg template
     */
    public $template = '<svg width="{x}" height="{y}" viewBox="0 0 {x} {y}" preserveAspectRatio="none"><defs>{linearGradient}</defs><g><polygon points="{polygon}" fill="url(#gradient)"/><polyline points="{polyline}" fill="none" stroke="{stroke}" stroke-width="1"/></g></svg>';

    /**
     * ```php
     * [
     *  [x, y]
     * ]
     * ```
     * @var array Each point is define by a X and a Y coordinate.
     */
    protected $points = [];
    /**
     * @var TimelinePanel
     */
    protected $panel;


    /**
     * @inheritdoc
     */
    public function __construct(TimelinePanel $panel, $config = [])
    {
        parent::__construct($config);
        $this->panel = $panel;
        foreach ($this->listenMessages as $panel) {
            if (isset($this->panel->module->panels[$panel]->data['messages'])) {
                $this->addPoints($this->panel->module->panels[$panel]->data['messages']);
            }
        }
    }

    /**
     * @return string
     */
    public function __toString()
    {
        if ($this->points === []) {
            return '';
        }

        return strtr($this->template, [
            '{x}' => $this->x,
            '{y}' => $this->y,
            '{stroke}' => $this->stroke,
            '{polygon}' => $this->polygon(),
            '{polyline}' => $this->polyline(),
            '{linearGradient}' => $this->linearGradient()
        ]);
    }

    /**
     * @return bool Has points
     */
    public function hasPoints()
    {
        return ($this->points !== []);
    }

    /**
     * @param array $messages log messages. See [[Logger::messages]] for the structure
     * @return int added points
     */
    protected function addPoints($messages)
    {
        $hasPoints = $this->hasPoints();

        $memory = $this->panel->memory / 100; // 1 percent memory
        $yOne = $this->y / 100; // 1 percent Y coordinate
        $xOne = $this->panel->duration / $this->x; // 1 percent X coordinate

        $i = 0;
        foreach ($messages as $message) {
            if (empty($message[5])) {
                break;
            }
            ++$i;
            $this->points[] = [
                ($message[3] * 1000 - $this->panel->start) / $xOne,
                $this->y - ($message[5] / $memory * $yOne),
            ];
        }

        if ($hasPoints && $i) {
            usort($this->points, function ($a, $b) {
                return ($a[0] < $b[0]) ? -1 : 1;
            });
        }
        return $i;
    }

    /**
     * @return string Points attribute for polygon path
     */
    protected function polygon()
    {
        $str = "0,$this->y ";
        foreach ($this->points as $point) {
            list($x, $y) = $point;
            $str .= "{$x},{$y} ";
        }
        $str .= $this->x - 0.001 . ",{$y} {$this->x},{$this->y}";
        return $str;
    }

    /**
     * @return string Points attribute for polyline path
     */
    protected function polyline()
    {
        $str = "0,$this->y ";
        foreach ($this->points as $point) {
            list($x, $y) = $point;
            $str .= "{$x},{$y} ";
        }
        $str .= "$this->x,{$y}";
        return $str;
    }

    /**
     * @return string
     */
    protected function linearGradient()
    {
        $gradient = '<linearGradient id="gradient" x1="0" x2="0" y1="1" y2="0">';
        foreach ($this->gradient as $percent => $color) {
            $gradient .= '<stop offset="' . $percent . '%" stop-color="' . $color . '"></stop>';
        }
        return $gradient . '</linearGradient>';
    }

}