check if number is on whatsapp

package main

import (
    "bytes"
    "encoding/json"
    "fmt"
    "net/http"
)

type checkContacts struct {
    Blocking    string   `json:"blocking"`
    Contacts    []string `json:"contacts"`
    ForceCheck  bool     `json:"force_check"`
}

type contactStatus struct {
    WAID    string `json:"wa_id"`
    Input   string `json:"input"`
    Status  string `json:"status"`
}

type checkContactsResponse struct {
    Contacts  []contactStatus  `json:"contacts"`
}

func checkNumberOnWhatsApp(apiURL string, apiToken string, phoneNumber string, blocking string) (bool, error) {
    data := &checkContacts{
        Blocking: blocking,
        Contacts: []string{phoneNumber},
        ForceCheck: false,
    }
    jsonValue, _ := json.Marshal(data)
    request, err := http.NewRequest("POST", apiURL, bytes.NewBuffer(jsonValue))
    if err != nil {
        return false, err
    }
    request.Header.Set("Authorization", "Bearer "+apiToken)
    request.Header.Set("Content-Type", "application/json")
    client := &http.Client{}
    response, err := client.Do(request)
    if err != nil {
        return false, err
    }
    defer response.Body.Close()

    var checkContactsResp checkContactsResponse
    json.NewDecoder(response.Body).Decode(&checkContactsResp)

    if len(checkContactsResp.Contacts)>0 {
        contact := checkContactsResp.Contacts[0]
        if contact.Status == "valid" {
            return true, nil
        }
    }
    return false, nil
}

func main() {
    apiURL := "https://api.whatsapp.com/v1/contacts"
    apiToken := "YOUR_API_TOKEN"
    phoneNumber := "1234567890"
    onWhatsApp, err := checkNumberOnWhatsApp(apiURL, apiToken, phoneNumber, "no_wait")
    if err != nil {
        fmt.Println(err)
        return
    }

    if onWhatsApp {
        fmt.Println(phoneNumber, "is on WhatsApp")
    } else {
        fmt.Println(phoneNumber, "is not on WhatsApp")
    }
}