<?php
defined('BASEPATH') OR exit('No direct script access allowed');
require_once APPPATH . 'controllers/api/BaseController.php';

/**
 * Notes:生成验证码
 * Created on: 2022/8/29 17:15
 * Created by: dengbw
 */
class Captcha extends BaseController
{
    private $redis;

    public function __construct()
    {
        parent::__construct();
        $this->redis = &load_cache('redis');
    }

    public function index_get()
    {
        $this->load->library('MyCaptcha');
        $myCaptcha = new MyCaptcha();
        $re = $myCaptcha->create(5, ['width' => 16, 'height' => 20, 'pnum' => 50, 'base64' => 1]);
        $code_key = $this->generateSign();
        $this->redis->save($code_key, $re['text'], 5 * 60);
        $data = ['base64' => $re['base64'], 'code_key' => $code_key];
        $this->return_response($data);
    }

    function generateSign()
    {
        $sign = md5(mt_rand() . 'mycaptchamarket');
        // 拼接上签名作为 Redis 的 key
        $key = 'code_' . $sign;
        if ($this->redis->exists($key)) {
            // 如果生成的 Sign 已存在，就进行递归，直到生成出一个不存在的。
            return $this->generateSign();
        }
        return $key;
    }

}