<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006~2016 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------

namespace think\template\driver;

use think\Exception;

class File
{
    /**
     * 写入编译缓存
     * @string $cacheFile 缓存的文件名
     * @string $content 缓存的内容
     * @return void|array
     */
    public function write($cacheFile, $content)
    {
        // 检测模板目录
        $dir = dirname($cacheFile);
        if (!is_dir($dir)) {
            mkdir($dir, 0777, true);
        }
        // 生成模板缓存文件
        if (false === file_put_contents($cacheFile, $content)) {
            throw new Exception('cache write error :' . $cacheFile, 11602);
        }
    }

    /**
     * 读取编译编译
     * @string $cacheFile 缓存的文件名
     * @array $vars 变量数组
     * @boolean $isReturn 是否返回内容
     * @return void|array
     */
    public function read($cacheFile, $vars = [], $isReturn = false)
    {
        if (!empty($vars) && is_array($vars)) {
            // 模板阵列变量分解成为独立变量
            extract($vars, EXTR_OVERWRITE);
        }
        if ($isReturn) {
            //载入模版缓存文件
            include $cacheFile;
        } else {
            return include $cacheFile;
        }
    }

    /**
     * 检查编译缓存是否有效
     * @array $template 用到的模板更新时间列表
     * @string $cacheFile 缓存的文件名
     * @int $cacheTime 缓存时间
     * @return boolean
     */
    public function check($files, $cacheFile, $cacheTime)
    {
        foreach($files as $time => $path) {
            if (is_file($path) && filemtime($path) > $time) {
                // 模板文件如果有更新则缓存需要更新
                return false;
            }
        }
        if (0 != $cacheTime && time() > filemtime($cacheFile) + $cacheTime) {
            // 缓存是否在有效期
            return false;
        }
        return true;
    }
}