<?php

namespace app\forms;

use yii\imagine\Image;

trait ImageTools
{
 /**
 * @param $fileUrl string 原始地址
 * @param $saveTo string 保存后的地址
 * @throws \Exception
 * 下载图片
 */
 public function downloadFile($fileUrl, $saveTo)
 {
 $in = fopen($fileUrl, "rb");
 if ($in === false) {
 throw new \Exception('发布失败,请检查站点目录是否有写入权限');
 }
 $out = fopen($saveTo, "wb");
 if ($out === false) {
 throw new \Exception('发布失败,请检查站点目录是否有写入权限');
 }
 while ($chunk = fread($in, 8192)) {
 fwrite($out, $chunk, 8192);
 }
 fclose($in);
 fclose($out);
 }

 /**
 * @param $url
 * @return mixed
 * @throws \Exception
 * 获取图片后缀
 */
 protected function getImageExtension($url)
 {
 if (!function_exists('getimagesize')) {
 throw new \Exception('getimagesize函数无法使用');
 }
 try {
 $imgInfo = getimagesize($url);
 if (!$imgInfo) {
 Error('无效的图片链接' . $url);
 }
 $arr = [
 1 => 'gif',
 2 => 'jpg',
 3 => 'png',
 ];
 if (!isset($arr[$imgInfo[2]])) {
 throw new \Exception('仅支持jpg、png格式的图片');
 }
 return $arr[$imgInfo[2]];
 } catch (\Exception $e) {
 Error($e->getMessage());
 }
 }

 /**
 * 图片压缩
 * @param $input
 * @param $output
 */
 private function zoomImage($input, $output)
 {
 Image::thumbnail($input, 80, 80,
 \Imagine\Image\ManipulatorInterface::THUMBNAIL_INSET)
 ->save($output,
 ['quality' => 80]);
 }

 private function base64EncodeImage($image_file)
 {
 if (!$image_file) {
 return '';
 }
 $cacheKey = 'LIVE_IMAGE_' . $image_file;
 $img = \Yii::$app->cache->get($cacheKey);
 if ($img) {
 return $img;
 }
 $content = file_get_contents($image_file);
 $type = getimagesize($image_file);//取得图片的大小,类型等
 switch ($type[2]) {//判读图片类型
 case 1:
 $img_type = "gif";
 break;
 case 2:
 $img_type = "jpg";
 break;
 case 3:
 $img_type = "png";
 break;
 }
 $temp = \Yii::$app->basePath . '/web/temp/';
 if (!is_dir($temp)) {
 mkdir($temp);
 }
 $imageName = 'live_' . md5($image_file) . '.' . $img_type;
 if (!file_exists($temp . $imageName)) {
 file_put_contents($temp . $imageName, $content);
 }
 $img = \Yii::$app->request->hostInfo . \Yii::$app->request->baseUrl . '/temp/' . $imageName;
 \Yii::$app->cache->set($cacheKey, $img, 60 * 60 * 24 * 7);
 return $img;
 }
}