\ticky\captcha\drivergd

<?php

namespace ticky\captcha\driver;

use ticky\captcha\contract;
use ticky\config;
use ticky\session;

class gd extends contract {

    private $width; //验证码图片宽度，单位px
    private $height; //验证码图片高度，单位px
    private $length; // 验证码长度(个数)
    private $code; // 验证码内容
    private $name; //验证码名，用来区分不同用途
    private $expire; //验证码过期时间，单位秒
    private $disturb; //是否有干扰元素
    private $im;
    private static $error; //错误信息

    public function __construct($config) {
        if (!extension_loaded('gd')) {
            throw new exception('GD Error', 'GD extension not install');
        }
        $this->config = $config ? $config['gd'] : config::get('captcha', 'gd');
        $this->width = $this->config['width'];
        $this->height = $this->config['height'];
        $this->length = $this->config['length'];
        $this->disturb = $this->config['disturb'];
        $this->expire = $this->config['expire'];
        self::$error = [
            1000 => '验证码标识名为空',
            1005 => '要验证的验证码为空',
            1010 => '验证码不存在或已过期',
            1015 => '验证失败',
        ];
    }

    public function width($width) {
        $this->width = $width;
        return $this;
    }

    public function height($height) {
        $this->height = $height;
        return $this;
    }

    public function length($length) {
        $this->length = $length;
        return $this;
    }

    public function disturb($disturb = true) {
        $this->disturb = $disturb;
        return $this;
    }

    public function name($name) {
        if ($name) {
            $this->name = $name;
        }
        return $this;
    }

    public function expire($expire) {
        if (isset($expire)) {
            $this->expire = $expire;
        }
        return $this;
    }

    public function show($name) {
        if (isset($name)) {
            $this->name = $name;
        }
        if (!$this->name) {
            return ['code' => 1000, 'msg' => self::$error[1000]];
        }
        $this->createImg();
        if ($this->disturb) {
            $this->setDisturb();
        }
        $this->setCode();
        $this->output();
    }

    // 创建图片
    private function createImg() {
        $this->im = imagecreatetruecolor($this->width, $this->height);
        $bgColor = imagecolorallocate($this->im, 255, 255, 255);
        imagefill($this->im, 0, 0, $bgColor);
    }

    // 设置干扰元素
    private function setDisturb() {
        $area = ($this->width * $this->height) / 20;
        $num = ($area > 250) ? 250 : $area;
        // 加入点干扰
        for ($i = 0; $i < $num; $i++) {
            $color = imagecolorallocate($this->im, rand(0, 255), rand(0, 255), rand(0, 255));
            imagesetpixel($this->im, rand(1, $this->width - 2), rand(1, $this->height - 2), $color);
        }
        // 加入弧线
        for ($i = 0; $i <= 5; $i++) {
            $color = imagecolorallocate($this->im, rand(128, 255), rand(125, 255), rand(100, 255));
            imagearc($this->im, rand(0, $this->width), rand(0, $this->height), rand(30, 300), rand(20, 200), 50, 30, $color);
        }
    }

    // 设置验证码
    private function setCode() {
        $token = "23456789abcdefghijkmnpqrstuvwxyzABCDEFGHIJKMNPQRSTUVWXYZ";
        for ($i = 0; $i < $this->length; $i++) {
            $color = imagecolorallocate($this->im, rand(50, 250), rand(100, 250), rand(128, 250));
            $size = rand(floor($this->height / 5), floor($this->height / 3));
            $x = floor($this->width / $this->length) * $i + 5;
            $y = rand(0, $this->height - 20);
            $this->code .= $token{rand(0, strlen($token) - 1)};
            imagechar($this->im, $size, $x, $y, $this->code{$i}, $color);
        }
        session('verify_code_' . $this->name, $this->code, $this->expire);
    }

    // 验证是否正确
    public function check($name, $code) {
        if (!name) {
            return ['code' => 1000, 'msg' => self::$error[1000]];
        }
        $verifyCode = session('verify_code_' . $name);
        if (!$code) {
            return ['code' => 1005, 'msg' => self::$error[1005]];
        }
        if (!$verifyCode) {
            return ['code' => 1010, 'msg' => self::$error[1010]];
        }
        if (strtolower($code) != strtolower($verifyCode)) {
            return ['code' => 1015, 'msg' => self::$error[1015]];
        }
        return ['code' => 200, 'msg' => '验证通过'];
    }

    // 输出图片
    private function output() {
        if (imagetypes() & IMG_JPG) {
            header('Content-type:image/jpeg');
            imagejpeg($this->im);
        } elseif (imagetypes() & IMG_GIF) {
            header('Content-type: image/gif');
            imagegif($this->im);
        } elseif (imagetype() & IMG_PNG) {
            header('Content-type: image/png');
            imagepng($this->im);
        } else {
           die("Don't support image type!");
        }
        // 释放资源
        imagedestroy($this->im);
    }

}