<?php

/**
 * 图片处理，生成缩略图和添加水印图片
 * Created by PhpStorm.
 * User: andy
 * Date: 17-1-3
 * Time: 上午11:55
 */
class Image
{
    //原图
    private $imgPath;   //图片地址
    private $width;     //图片宽度
    private $height;    //图片高度
    private $type;      //图片类型
    private $img;       //图片(图像流)

    //缩略图
    private $newImg;    //缩略图(图像流)
    private $newWidth;
    private $newHeight;

    //水印图路径
    private $waterMarkPath;

    //输出图像质量,jpg有效
    private $quality;

    /**
     * Image constructor.
     * @param string $imagePath 图片路径
     * @param string $markPath 水印图片路径
     * @param int $new_width 缩略图宽度
     * @param int $new_height 缩略图高度
     * @param int $quality JPG图片格输出质量
     */
    public function __construct(string $imagePath,
                                string $markPath = null,
                                int $new_width = null,
                                int $new_height = null,
                                int $quality = 75)
    {
        $this->imgPath = $_SERVER['DOCUMENT_ROOT'] . $imagePath;
        $this->waterMarkPath = $markPath;
        $this->newWidth = $new_width ? $new_width : $this->width;
        $this->newHeight = $new_height ? $new_height : $this->height;
        $this->quality = $quality ? $quality : 75;

        list($this->width, $this->height, $this->type) = getimagesize($this->imgPath);
        $this->img = $this->_loadImg($this->imgPath, $this->type);


        //生成缩略图
        $this->_thumb();
        //添加水印图片
        if (!em