<?php
/**
 * name:API核心类
 * update:2020/12
 * author:xiaoz<xiaoz93@outlook.com>
 * blog:xiaoz.me
 */
class Api {
    protected $db;
    public function __construct($db){
        $this->db = $db;
        //返回json类型
        header('Content-Type:application/json; charset=utf-8');
    }
    /**
     * name:创建分类目录
     */
    public function add_category($token,$name,$property = 0,$weight = 0,$description = ''){
        $this->auth($token);
        $data = [
            'name'          =>  $name,
            'add_time'      =>  time(),
            'weight'        =>  $weight,
            'property'      =>  $property,
            'description'   =>  $description
        ];
        //插入分类目录
        $this->db->insert("on_categorys",$data);
        //返回ID
        $id = $this->db->id();
        //如果id为空（NULL），说明插入失败了，姑且认为是name重复导致
        if( empty($id) ){
            $this->err_msg(-1000,'Categorie already exist!');
        }
        else{
            //成功并返回json格式
            $data = [
                'code'      =>  0,
                'id'        =>  intval($id)
            ];
            exit(json_encode($data));
        }
        
    }
    /**
     * 修改分类目录
     * 
     */
    public function edit_category($token,$id,$name,$property = 0,$weight = 0,$description = ''){
        $this->auth($token);
        //如果id为空
        if( empty($id) ){
            $this->err_msg(-1003,'The category ID cannot be empty!');
        }
        //如果分类名为空
        elseif( empty($name) ){
            $this->err_msg(-1004,'The category name cannot be empty!');
        }
        //更新数据库
        else{
            $data = [
                'name'          =>  $name,
                'up_time'      =>  time(),
                'weight'        =>  $weight,
                'property'      =>  $property,
                'description'   =>  $description
            ];
            $re = $this->db->update('on_categorys',$data,[ 'id' => $id]);
            //var_dump( $this->db->log() );
            //获取影响行数
            $row = $re->rowCount();
            if($row) {
                $data = [
                    'code'  =>  0,
                    'msg'   =>  'successful'
                ];
                exit(json_encode($data));
            }
            else{
                $this->err_msg(-1005,'The category name already exists!');
            }
        }
    }
    /**
     * 删除分类目录
     */
    public function del_category($token,$id) {
        //验证授权
        $this->auth($token);
        //如果id为空
        if( empty($id) ){
            $this->err_msg(-1003,'The category ID cannot be empty!');
        }
        //如果分类目录下存在数据
        $count = $this->db->count("on_links", [
            "fid" => $id
        ]);
        //如果分类目录下存在数据，则不允许删除
        if($count > 0) {
            $this->err_msg(-1006,'The category is not empty and cannot be deleted!');
        }
        else{
            $data = $this->db->delete('on_categorys',[ 'id' => $id] );
            //返回影响行数
            $row = $data->rowCount();
            if($row) {
                $data = [
                    'code'  =>  0,
                    'msg'   =>  'successful'
                ];
                exit(json_encode($data));
            }
            else{
                $this->err_msg(-1007,'The category delete failed!');
            }
        }
    }
    
    /**
     * name:返回错误（json）
     * 
     */
    protected function err_msg($code,$err_msg){
        $data = [
            'code'      =>  $code,
            'err_msg'   =>  $err_msg
        ];
        //返回json类型
        header('Content-Type:application/json; charset=utf-8');
        exit(json_encode($data));
    }
    /**
     * name:验证方法
     */
    protected function auth($token){
        //计算正确的token：用户名 + TOKEN
        $token_yes = md5(USER.TOKEN);
        //如果token为空，则验证cookie
        if(empty($token)) {
            if( !$this->is_login() ) {
                $this->err_msg(-1002,'Authorization failure!');
            }
        }
        else if($token != $token_yes){
            $this->err_msg(-1002,'Authorization failure!');
        }
        else{
            return true;
        }
    }
    /**
     * name:添加链接
     */
    public function add_link($token,$fid,$title,$url,$description = '',$weight = 0,$property = 0){
        $this->auth($token);
        $fid = intval($fid);
        //检测链接是否合法
        $this->check_link($fid,$title,$url);
        //合并数据
        $data = [
            'fid'           =>  $fid,
            'title'         =>  $title,
            'url'           =>  $url,
            'description'   =>  $description,
            'add_time'      =>  time(),
            'weight'        =>  $weight,
            'property'      =>  $property
        ];
        //插入数据库
        $re = $this->db->insert('on_links',$data);
        //返回影响行数
        $row = $re->rowCount();
        //如果为真
        if( $row ){
            $id = $this->db->id();
            $data = [
                'code'      =>  0,
                'id'        =>  $id
            ];
            exit(json_encode($data));
        }
        //如果插入失败
        else{
            $this->err_msg(-1011,'The URL already exists!');
        }
    }
    /**
     * name:修改链接
     */
    public function edit_link($token,$id,$fid,$title,$url,$description = '',$weight = 0,$property = 0){
        $this->auth($token);
        $fid = intval($fid);
        //检测链接是否合法
        $this->check_link($fid,$title,$url);
        //查询ID是否存在
        $count = $this->db->count('on_links',[ 'id' => $id]);
        //如果id不存在
        if( (empty($id)) || ($count == false) ) {
            $this->err_msg(-1010,'link id not exists!');
        }
        //合并数据
        $data = [
            'fid'           =>  $fid,
            'title'         =>  $title,
            'url'           =>  $url,
            'description'   =>  $description,
            'up_time'       =>  time(),
            'weight'        =>  $weight,
            'property'      =>  $property
        ];
        //插入数据库
        $re = $this->db->update('on_links',$data,[ 'id' => $id]);
        //返回影响行数
        $row = $re->rowCount();
        //如果为真
        if( $row ){
            $id = $this->db->id();
            $data = [
                'code'      =>  0,
                'msg'        =>  'successful'
            ];
            exit(json_encode($data));
        }
        //如果插入失败
        else{
            $this->err_msg(-1011,'The URL already exists!');
        }
    }
    /**
     * 删除链接
     */
    public function del_link($token,$id){
        //验证token是否合法
        $this->auth($token);
        //查询ID是否存在
        $count = $this->db->count('on_links',[ 'id' => $id]);
        //如果id不存在
        if( (empty($id)) || ($count == false) ) {
            $this->err_msg(-1010,'link id not exists!');
        }
        else{
            $re = $this->db->delete('on_links',[ 'id' =>  $id] );
            if($re) {
                $data = [
                    'code'  =>  0,
                    'msg'   =>  'successful'
                ];
                exit(json_encode($data));
            }
            else{
                $this->err_msg(-1010,'link id not exists!');
            }
        }
    }
    /**
     * 验证链接合法性
     */
    protected function check_link($fid,$title,$url){
        //如果父及（分类）ID不存在
        if( empty($fid )) {
            $this->err_msg(-1007,'The category id(fid) not exist!');
        }
        //如果父及ID不存在数据库中
        //验证分类目录是否存在
        $count = $this->db->count("on_categorys", [
            "id" => $fid
        ]);
        if ( empty($count) ){
            $this->err_msg(-1007,'The category not exist!');
        }
        //如果链接标题为空
        if( empty($title) ){
            $this->err_msg(-1008,'The title cannot be empty!');
        }
        //链接不能为空
        if( empty($url) ){
            $this->err_msg(-1009,'URL cannot be empty!');
        }
        //链接不合法
        if( !filter_var($url, FILTER_VALIDATE_URL) ) {
            $this->err_msg(-1010,'URL is not valid!');
        }
        return true;
    }
    /**
     * 查询分类目录
     */
    public function category_list($page,$limit){
        $offset = ($page - 1) * $limit;
        //如果成功登录，则查询所有
        if( $this->is_login() ){
            $sql = "SELECT * FROM on_categorys ORDER BY weight DESC,id DESC LIMIT {$limit} OFFSET {$offset}";
        }
        else{
            $sql = "SELECT * FROM on_categorys WHERE property = 0 ORDER BY weight DESC,id DESC LIMIT {$limit} OFFSET {$offset}";
        }
        //统计总数
        $count = $this->db->count('on_categorys','*');
        //原生查询
        $datas = $this->db->query($sql)->fetchAll();
        $datas = [
            'code'      =>  0,
            'msg'       =>  '',
            'count'     =>  $count,
            'data'      =>  $datas
        ];
        exit(json_encode($datas));
    }
    /**
     * 查询链接
     */
    public function link_list($page,$limit,$token = ''){
        $offset = ($page - 1) * $limit;
        //如果成功登录，但token为空
        if( ($this->is_login()) && (empty($token)) ){
            //统计总数
            $count = $this->db->count('on_links','*');
            $sql = "SELECT *,(SELECT name FROM on_categorys WHERE id = on_links.fid) AS category_name FROM on_links ORDER BY weight DESC,id DESC LIMIT {$limit} OFFSET {$offset}";
        }
        
        //如果token验证通过
        elseif( (!empty($token)) && ($this->auth($token)) ) {
            //统计总数
            $count = $this->db->count('on_links','*');
            $sql = "SELECT *,(SELECT name FROM on_categorys WHERE id = on_links.fid) AS category_name FROM on_links ORDER BY weight DESC,id DESC LIMIT {$limit} OFFSET {$offset}";
        }
        else{
            //统计总数
            $count = $this->db->count('on_links','*',[ 'property'   =>  0 ]);
            $sql = "SELECT *,(SELECT name FROM on_categorys WHERE id = on_links.fid) AS category_name FROM on_links WHERE property = 0 ORDER BY weight DESC,id DESC LIMIT {$limit} OFFSET {$offset}";
        }
       
        //原生查询
        $datas = $this->db->query($sql)->fetchAll();
        $datas = [
            'code'      =>  0,
            'msg'       =>  '',
            'count'     =>  $count,
            'data'      =>  $datas
        ];
        exit(json_encode($datas));
    }
    /**
     * 验证是否登录
     */
    protected function is_login(){
        $key = md5(USER.PASSWORD.$this->getIP().'onenav');
        //获取session
        $session = $_COOKIE['key'];
        //如果已经成功登录
        if($session == $key) {
            return true;
        }
        else{
            return false;
        }
    }
    /**
     * 获取链接信息
     */
    public function get_link_info($token,$url){
        $this->auth($token);
        //检查链接是否合法
        //链接不合法
        if( !filter_var($url, FILTER_VALIDATE_URL) ) {
            $this->err_msg(-1010,'URL is not valid!');
        }
        //获取网站标题
        $c = curl_init(); 
        curl_setopt($c, CURLOPT_URL, $url); 
        curl_setopt($c, CURLOPT_RETURNTRANSFER, 1); 
        curl_setopt($c, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($c, CURLOPT_SSL_VERIFYHOST, false);
        //设置超时时间
        curl_setopt($c , CURLOPT_TIMEOUT, 10);
        $data = curl_exec($c); 
        curl_close($c); 
        $pos = strpos($data,'utf-8'); 
        if($pos===false){$data = iconv("gbk","utf-8",$data);} 
        preg_match("/<title>(.*)<\/title>/i",$data, $title); 
        
        $link['title'] =  $title[1]; 

        //获取网站描述
        $tags = get_meta_tags($url);
        $link['description'] = $tags['description'];
        
        $data = [
            'code'      =>  0,
            'data'      =>  $link
        ];
        exit(json_encode($data));
    }
    /**
     * 获取IP
     */
    //获取访客IP
    protected function getIP() { 
    if (getenv('HTTP_CLIENT_IP')) { 
    $ip = getenv('HTTP_CLIENT_IP'); 
    } 
    elseif (getenv('HTTP_X_FORWARDED_FOR')) { 
        $ip = getenv('HTTP_X_FORWARDED_FOR'); 
    } 
        elseif (getenv('HTTP_X_FORWARDED')) { 
        $ip = getenv('HTTP_X_FORWARDED'); 
    } 
    elseif (getenv('HTTP_FORWARDED_FOR')) { 
    $ip = getenv('HTTP_FORWARDED_FOR'); 
    } 
    elseif (getenv('HTTP_FORWARDED')) { 
    $ip = getenv('HTTP_FORWARDED'); 
    } 
    else { 
        $ip = $_SERVER['REMOTE_ADDR']; 
    } 
        return $ip; 
    } 

    //
}