package feishu

import (
	"crypto/hmac"
	"crypto/sha256"
	"encoding/base64"
	"encoding/json"
	"fmt"
	"time"
)

type SecretMethod struct {
	WhileIpMethod
	secret string
}

func (m *SecretMethod) Init(hook, secret string) {
	m.hook, m.secret = hook, secret
}

func (m *SecretMethod) sign(timestamp int64) (string, error) {
	//timestamp + key 做sha256, 再进行base64 encode
	stringToSign := fmt.Sprintf("%v", timestamp) + "\n" + m.secret
	var data []byte
	h := hmac.New(sha256.New, []byte(stringToSign))
	_, err := h.Write(data)
	if err != nil {
		return "", err
	}
	signature := base64.StdEncoding.EncodeToString(h.Sum(nil))
	return signature, nil
}

func (m *SecretMethod) getBody(val map[string]interface{}) ([]byte, error) {
	tm := time.Now().Unix()
	sign, err := m.sign(tm)
	if err != nil {
		return nil, err
	}
	val["timestamp"] = fmt.Sprintf("%d", tm)
	val["sign"] = sign
	return json.Marshal(val)
}

func (m *SecretMethod) SendSimpleMsg(content string) (bool, error) {
	body, err := m.getBody(getSimpleMsg(content))
	if err != nil {
		return false, err
	}
	return post(m.hook, body)
}

func (m *SecretMethod) SendRichMsg(title string, content RichContent) (bool, error) {
	body, err := m.getBody(getRichMsg(title, content))
	if err != nil {
		return false, err
	}
	return post(m.hook, body)
}