package email

import (
	"scd_check_tools/conf"
	"scd_check_tools/logger"
	"encoding/json"
	"errors"
	"fmt"
	"io/ioutil"
	"os"
	"strconv"
	"strings"

	"gopkg.in/gomail.v2"
)

var EmailConfig = new(emailConfig)

//邮件配置
type emailConfig struct {
	Enable       bool   //是否启动邮件
	SmtpHost     string `json:"smtp_host"`
	SmtpPort     string `json:"smtp_port"`
	Username     string `json:"send_email"`    //发送邮件邮箱
	SendNickname string `json:"send_nickname"` //发送者名称
	AuthCode     string `json:"auth_code"`     //发送授权码。需要在邮件平台上生成
}

func (c *emailConfig) Load() {
	cnffile := "conf/email.cnf"
	logger.Logger.Println("加载Email配置文件:" + cnffile)
	fileHanlder, err := os.Open(cnffile)
	if err != nil {
		logger.Logger.Println("未发现邮件配置：conf/email.cnf")
		return
	}
	txt, err := ioutil.ReadAll(fileHanlder)
	if err != nil {
		logger.Logger.Error(err)
		return
	}
	defer fileHanlder.Close()
	txtStr := string(txt)
	if txtStr == "" {
		logger.Logger.Error(errors.New("邮件配置文件conf/email.cnf内容不正确"))
		return
	}
	err = json.Unmarshal(txt, &EmailConfig)
	if err != nil {
		logger.Logger.Error(err)
		return
	}
	if EmailConfig.SmtpHost == "" {
		logger.Logger.Error(errors.New("邮件配置文件conf/email.cnf内容不正确：smtp_host为空！"))
		return
	}
	if EmailConfig.SmtpPort == "" {
		logger.Logger.Error(errors.New("邮件配置文件conf/email.cnf内容不正确：smtp_port为空！"))
		return
	}
	_, err = strconv.Atoi(EmailConfig.SmtpPort)
	if err != nil {
		logger.Logger.Error(errors.New("邮件配置文件conf/email.cnf内容不正确：smtp_port不是正确的端口号！"))
		return
	}
	if EmailConfig.Username == "" {
		logger.Logger.Error(errors.New("邮件配置文件conf/email.cnf内容不正确：send_email为空！"))
		return
	}
	if EmailConfig.AuthCode == "" {
		logger.Logger.Error(errors.New("邮件配置文件conf/email.cnf内容不正确：auth_code为空！"))
		return
	}
	if EmailConfig.SendNickname == "" {
		EmailConfig.SendNickname = conf.GlobalConfig["appname"]
	}
	EmailConfig.Enable = true
	logger.Logger.Debug(fmt.Sprintf("邮件配置文件加载完成：%+v", EmailConfig))
}

//邮件发送对象。
//暂不支持附件发送
type Send struct {
	//接收邮箱
	ToEmail string
	//抄送邮箱列表
	CcEmails []string
	//邮件标题
	Subject string
	//邮件正文内容
	Content string
}

//邮件发送
func (c *Send) To() error {
	return c.SendEmail(c.ToEmail, c.Subject, c.Content, c.CcEmails)
}

//邮件发送
func (c *Send) SendEmail(toEmail, subject, content string, cc ...[]string) error {
	if !EmailConfig.Enable {
		return nil
	}
	if toEmail == "" {
		return errors.New("接收邮箱不能为空！")
	}
	if subject == "" {
		subject = "无标题"
	}
	if content == "" {
		return errors.New("邮件内容不能为空！")
	}
	s := gomail.NewMessage()
	s.SetHeader("From", s.FormatAddress(EmailConfig.Username, EmailConfig.SendNickname))
	s.SetHeader("To", toEmail)
	s.SetHeader("Subject", subject)
	if len(cc) > 0 {
		s.SetHeader("Cc", strings.Join(cc[0], ","))
	}
	//附件
	//s.Attach("")
	s.SetBody("text/html", content)
	port, _ := strconv.Atoi(EmailConfig.SmtpPort)
	s1 := gomail.NewDialer(EmailConfig.SmtpHost, port, EmailConfig.Username, EmailConfig.AuthCode)
	err := s1.DialAndSend(s)
	if err != nil {
		return err
	}
	return nil
}