<?php

class Company_SocialCoupons_InstagramController extends Mage_Core_Controller_Front_Action
{
    public function followAction() {

       $status = Mage::helper('socialcoupons/instagram')->postFollow();

       if ($status == 'follows') {

            // 1. ADD DATA TO MY DATABASE using my custom model
            //    - Ex. Mage::getModel('socialcoupons/instagram')->setInstagramId(*IGID*), etc.
            // 2. CREATE COUPON
            // 3. EMAIL COUPON TO CUSTOMER
       }
}

class Company_SocialCoupons_Helper_Instagram extends Mage_Core_Helper_Abstract
{

public function getfollow() {

    $accessToken = $this->getAccessToken();
    $relationshipsUrl = 'https://api.instagram.com/v1/users/' . $this->getUserId() . '/relationship?access_token=' . $accessToken;

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $relationshipsUrl);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array('Accept: application/json'));
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    $jsonData = curl_exec($ch);
    curl_close($ch);

    $response = json_decode($jsonData, true);
    $status = $response['data']['outgoing_status'];
    return $status;
}

public function generateAccessToken($code) {

    // exchange code for access token
    $accessTokenUrl = 'https://api.instagram.com/oauth/access_token';
    $data = array(
        'client_id'     => $this->getClientId(),
        'client_secret' => $this->getClientSecret(),
        'code'          => $code,
        'grant_type'    => 'authorization_code',
        'redirect_uri'  => $this->getRedirectUri()
    );

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $accessTokenUrl);
    curl_setopt($ch, CURLOPT_POST, count($data));
    curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($data));
    curl_setopt($ch, CURLOPT_HTTPHEADER, array('Accept: application/json'));
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    $jsonData = curl_exec($ch);
    curl_close($ch);

    $response = json_decode($jsonData, true);

    if (isset($response['error_type'])) { // no error

        Mage::getSingleton('core/session')->unsInstagramAccessToken();
        Mage::getSingleton('core/session')->addError($response['error_message']);
        return $this->_redirect('*/*/authorize');
    }

    $accessToken = $response['access_token'];
    $id          = $response['user']['id'];
    $username    = $response['user']['username'];

    Mage::getSingleton('core/session')->setInstagramAccessToken($accessToken);

    return array(
        'id'       => $id,
        'username' => $username
    );
}