Magento – Observer After save product

I have a Marketplace Module I want to send a mail after save Product

Controller.php

public function newpostAction()
{
    /**
     *  Check license key
     */
    Mage::helper('marketplace')->checkMarketplaceKey();
    /**
     *  Initilize customer and seller group id
     */
    $customerGroupId = $sellerGroupId = $customerStatus = '';
    Mage::app()->setCurrentStore(Mage_Core_Model_App::ADMIN_STORE_ID);
    $customerGroupId = Mage::getSingleton('customer/session')->getCustomerGroupId();
    $sellerGroupId = Mage::helper('marketplace')->getGroupId();
    $customerStatus = Mage::getSingleton('customer/session')->getCustomer()->getCustomerstatus();
    if (!$this->_getSession()->isLoggedIn() && $customerGroupId != $sellerGroupId) {
        Mage::getSingleton('core/session')->addError($this->__('You must have a Seller Account to access this page'));
        $this->_redirect('marketplace/seller/login');
        return;
    }
    /**
     *  Checking whether customer approved or not
     */
    if ($customerStatus != 1) {
        Mage::getSingleton('core/session')->addError($this->__('Admin Approval is required. Please wait until admin confirms your Seller Account'));
        $this->_redirect('marketplace/seller/login');
        return;
    }
    /**
     *  Initializing variables
     */
    $productNameTrim = $set = $setbase = $type = $store = $sellerId = '';
    /**
     *  Getting  product values
     */
    $type = $this->getRequest()->getPost('type');
    /**
     *  Attribute set
     */
    $set = $this->getRequest()->getPost('set');
    $setbase = $this->getRequest()->getPost('setbase');
    $store = $this->getRequest()->getPost('store');
    if (Mage::getSingleton('customer/session')->isLoggedIn()) {
        $sellerId = Mage::getSingleton('customer/session')->getCustomer()->getId();
    }
    /**
     *  Getting group id
     */
    $groupId = Mage::helper('marketplace')->getGroupId();
    /**
     *  Getting product data from product array
     */
    $productData = $this->getRequest()->getPost('product');

    $silkType = $productData['silktype'];

    /**
     *  Getting product categories from category_ids array
     */
    $categoryIds = $this->getRequest()->getPost('category_ids');
    if (!empty($productData['name']) && !empty($productData['description']) && isset($productData['price']) && isset($productData['stock_data']['qty']) && !empty($type)) {
        /**
         *  Initilize product weight
         */
        if ($type == 'simple') {
            if (!isset($productData['weight'])) {
                $productData['weight'] = 0;
            }
        }
        /**
         *  Assing product short description
         */
        if (!empty($productData['short_description'])) {
            $productData['short_description'] = $productData['short_description'];
        }
        /**
         *  Assign create at time
         */
        $createdAt = Mage::getModel('core/date')->gmtDate();

        /**
         *  Getting instance for catalog product collection
         */
        $product = Mage::getModel('catalog/product');
        /**
         *  Initialize product sku
         */

        if (isset($productData['sku'])) {
            $skuProductId = Mage::getModel('catalog/product')
                ->getIdBySku(trim($productData['sku']));
            if (!empty($skuProductId)) {
                /**
                 *  Error message redirect to create new product page
                 */
                Mage::getSingleton('core/session')->addError($this->__('SKU Not Available'));
                $this->_redirect('marketplace/product/new/');
                return;
            }
        }


        /**
         *  Initialize product attribute set id
         */
        if (!empty($set)) {
            $product->setAttributeSetId($set);
        } else {
            $sDefaultAttributeSetId = Mage::getSingleton('eav/config')
                ->getEntityType(Mage_Catalog_Model_Product::ENTITY)
                ->getDefaultAttributeSetId();
            $product->setAttributeSetId($sDefaultAttributeSetId);
        }

        /**
         *  Initialize product type
         */
        if (isset($type)) {
            $product->setTypeId($type);
        }


        /**
         *  Initialize product categories
         */
        if (isset($categoryIds)) {
            $product->setCategoryIds($categoryIds);
        }
        $product->setSilktype($silkType);

        /**
         *  Storing product data's to all store view
         */
        $product->setStoreId(0);

        /**
         *  Initialize product create at time
         */
        if (isset($createdAt)) {
            $product->setCreatedAt($createdAt);
        }
        /**
         *  Initialize seller id
         */
        if (isset($sellerId)) {
            $product->setSellerId($sellerId);
        }

        /**
         *  Initialize group id
         */
        if (isset($groupId)) {
            $product->setGroupId($groupId);
        }

        /**
         * Set is assign product
         */
        $product->setIsAssignProduct(0);

        $uploadsData = new Zend_File_Transfer_Adapter_Http();
        $filesDataArray = $uploadsData->getFileInfo();

        /**
         *  Checking whether image exist or not
         */
        if (!empty($filesDataArray)) {
            foreach ($filesDataArray as $key => $value) {
                /**
                 *  Initilize file name
                 */
                $filename = $key;

                if (substr($key, 0, 5) == 'image') {
                    if (isset($filesDataArray[$filename]['name']) && (file_exists($filesDataArray[$filename]['tmp_name']))) {
                        try {
                            $imagesPath[] = Mage::helper('marketplace/marketplace')->uploadImage($filename, $filesDataArray);
                        } catch (Exception $e) {
                            /**
                             *  Display error message for images upload
                             */
                            Mage::getSingleton('core/session')->addError($this->__($e->getMessage()));
                        }
                    }
                }
            }
        }

        /**
         *  Adding Product images
         */
        if (!empty($imagesPath)) {
            $product->setMediaGallery(array('images' => array(), 'values' => array()));
            foreach ($imagesPath as $value) {
                $product->addImageToMediaGallery($value, array('image', 'small_image', 'thumbnail'), false, false);
            }
        }


        /**
         *   Initialize dispatch event for product prepare
         */
        Mage::dispatchEvent(
            'catalog_product_prepare_save', array('product' => $product, 'request' => $this->getRequest())
        );

        /**
         *  Assign configurable product data
         */
        if ($type == 'configurable') {
            $attributeIds = $this->getRequest()->getPost('attributes');
            $isInStock = 1;
            if (isset($productData['stock_data']['is_in_stock'])) {
                $isInStock = $productData['stock_data']['is_in_stock'];
            }
            $productData['stock_data'] = array();
            if (count($attributeIds) >= 1) {
                $attributeIds = array_unique($attributeIds);
                $product->getTypeInstance()->setUsedProductAttributeIds($attributeIds);
                $configurableAttributesData = $product->getTypeInstance()->getConfigurableAttributesAsArray();
                $product->setCanSaveConfigurableAttributes(true);
                $product->setConfigurableAttributesData($configurableAttributesData);
                $product->setConfigurableProductsData(array());
            }
        }

        /**
         *  Adding data to product instanse
         */
        if (!empty($productData)) {
            $product->addData($productData);
        }
        /**
         *  Saving new product
         */
        try {
            $product->save();

            if ($type == 'configurable') {
                $stockItem = Mage::getModel('cataloginventory/stock_item');
                $stockItem->assignProduct($product);
                $stockItem->setData('stock_id', 1);
                if (isset($productData['stock_data']['qty'])) {
                    $stockItem->setData('qty', $productData['stock_data']['qty']);
                } else {
                    $stockItem->setData('qty', 0);
                }
                $stockItem->setData('use_config_min_qty', 1);
                $stockItem->setData('use_config_backorders', 1);
                $stockItem->setData('min_sale_qty', 1);
                $stockItem->setData('use_config_min_sale_qty', 1);
                $stockItem->setData('use_config_max_sale_qty', 1);
                $stockItem->setData('is_in_stock', $isInStock);
                $stockItem->setData('use_config_notify_stock_qty', 1);
                $stockItem->setData('manage_stock', 1);
                $stockItem->save();

                //This section is what was required.
                $stockStatus = Mage::getModel('cataloginventory/stock_status');
                $stockStatus->assignProduct($product);
                $stockStatus->saveProductStatus($product->getId(), 1);
            }

            $productId = $product->getId();

            /**
             * Load the product
             */
            $product = Mage::getModel('catalog/product')->load($productId);
            /**
             * Get all images
             */
            $mediaGallery = $product->getMediaGallery();
            /**
             * If there are images
             */
            if (isset($mediaGallery['images']) && !empty($store)) {
                /**
                 * Loop through the images
                 */
                $increment = 0;
                foreach ($mediaGallery['images'] as $image) {
                    /**
                     * Set the first image as the base image
                     */
                    if ($increment == $setbase) {
                        $product->setStoreId($store)
                            ->setImage($image['file'])
                            ->setSmallImage($image['file'])
                            ->setThumbnail($image['file']);

                        $product->save();
                    }
                    $increment++;
                    /**
                     * Stop
                     */

                }

            }

            /**
             *   Initialize product options
             */
            if (!empty($productData['options'])) {
                $product->setProductOptions($productData['options']);
                $product->setCanSaveCustomOptions(1);
                $product->save();
            }

            /**
             *  Checking whether image or not
             */
            if (!empty($imagesPath)) {
                foreach ($imagesPath as $deleteImage) {
                    /**
                     *  Checking whether image exist or not
                     */
                    if (file_exists($deleteImage)) {
                        /**
                         *  Delete images from temporary folder
                         */
                        unlink($deleteImage);
                    }
                }
            }

            /**
             *  Function for adding downloadable product sample and link data
             */
            $downloadProductId = $product->getId();
            if ($type == 'downloadable' && isset($downloadProductId) && isset($store)) {
                $this->addDownloadableProductData($downloadProductId, $store);
            }

            /**
             *  Success message redirect to manage product page
             */
            if (Mage::helper('marketplace')->getProductApproval() == 1) {
                Mage::getSingleton('core/session')->addSuccess($this->__('Your product is added successfully'));
                $mail = Mage::getModel('core/email');
                /*$mail = Mage::getModel('core/email');
                $mail->setToName('User');
                $mail->setToEmail('testmail98@gmail.com');
                $mail->setBody('Send Test mail to you.....');
                $mail->setSubject('Test Mail');
                $mail->setFromEmail('testmail@gmail.com');
                $mail->setFromName("Send Test mail to you.....");
                $mail->setType('html');// YOu can use Html or text as Mail format
                $mail->send(); */

                $sellerData = Mage::getSingleton('customer/session')->getCustomer();
                $sellerIdss = $sellerData->getId();
                $seller_mail = $sellerData->getEmail();

                $collectionss = Mage::getModel('followup/followup')->getCollection()
                    ->addFieldToFilter('seller_id', $sellerIdss)
                    ->addFieldToFilter('seller_email', $seller_mail);

                foreach ($collectionss as $item) {
                    $mycustomer_email = $item->getCustomerEmail();
                    $mycustomer_name = $item->getCustomerName();

                    $template_id = 'customer_update';
                    $email_to = $mycustomer_email;
                    $customer_name = $cus_name;
                    $email_template = Mage::getModel('core/email_template')->loadDefault($template_id);
                    $custom_variable = $mycustomer_name;
                    //$custom_variable1 = $cus_email;
                    $custom_variable1 = $this->getRequest()->getPost('store_name');
                    $email_template_variables = array(
                        'custom_variable' => $custom_variable,
                        'custom_variable1' => $custom_variable1);
                    //'custom_variable2' => $custom_variable2);
                    $sender_name = Mage::getStoreConfig(Mage_Core_Model_Store::XML_PATH_STORE_STORE_NAME);
                    $sender_email = Mage::getStoreConfig('trans_email/ident_general/email');
                    $email_template->setSenderName($sender_name);
                    $email_template->setSenderEmail($sender_email);
                    $email_template->send($email_to, $customer_name, $email_template_variables);

                }

                if (Mage::getStoreConfig('marketplace/product/addproductemailnotification') == 1) {
                    /**
                     *  Sending email for added new product
                     */
                    $templateId = (int)Mage::getStoreConfig('marketplace/product/addproductemailnotificationtemplate');
                    $adminEmailId = Mage::getStoreConfig('marketplace/marketplace/admin_email_id');
                    $toMailId = Mage::getStoreConfig("trans_email/ident_$adminEmailId/email");
                    $toName = Mage::getStoreConfig("trans_email/ident_$adminEmailId/name");

                    /**
                     *  Selecting template id
                     */
                    if ($templateId) {
                        $emailTemplate = Mage::getModel('core/email_template')->load($templateId);
                    } else {
                        $emailTemplate = Mage::getModel('core/email_template')
                            ->loadDefault('marketplace_product_addproductemailnotificationtemplate');
                    }
                    $customer = Mage::getModel('customer/customer')->load($sellerId);
                    $selleremail = $customer->getEmail();
                    $recipient = $toMailId;
                    $sellername = $customer->getName();
                    $productname = $product->getName();
                    $producturl = $product->getProductUrl();
                    $emailTemplate->setSenderName($sellername);
                    $emailTemplate->setSenderEmail($selleremail);
                    $emailTemplateVariables = (array('ownername' => $toName, 'sellername' => $sellername, 'selleremail' => $selleremail, 'productname' => $productname, 'producturl' => $producturl));
                    $emailTemplate->setDesignConfig(array('area' => 'frontend'));
                    $processedTemplate = $emailTemplate->getProcessedTemplate($emailTemplateVariables);
                    $emailTemplate->send($recipient, $sellername, $emailTemplateVariables);


                }
            } else {
                Mage::getSingleton('core/session')->addSuccess($this->__('Your product is awaiting moderation'));
                /*$mail = Mage::getModel('core/email');
                $mail->setToName('User');
                $mail->setToEmail('testmail98@gmail.com');
                $mail->setBody('Send Test mail to you.....');
                $mail->setSubject('Test Mail');
                $mail->setFromEmail('testmail@gmail.com');
                $mail->setFromName("Send Test mail to you.....");
                $mail->setType('html');// YOu can use Html or text as Mail format
                $mail->send(); */

                foreach ($collectionss as $item) {
                    $mycustomer_email = $item->getCustomerEmail();
                    $mycustomer_name = $item->getCustomerName();

                    $template_id = 'customer_update';
                    $email_to = $mycustomer_email;
                    $customer_name = $cus_name;
                    $email_template = Mage::getModel('core/email_template')->loadDefault($template_id);
                    $custom_variable = $mycustomer_name;
                    //$custom_variable1 = $cus_email;
                    $custom_variable1 = $this->getRequest()->getPost('store_name');
                    $email_template_variables = array(
                        'custom_variable' => $custom_variable,
                        'custom_variable1' => $custom_variable1);
                    //'custom_variable2' => $custom_variable2);
                    $sender_name = Mage::getStoreConfig(Mage_Core_Model_Store::XML_PATH_STORE_STORE_NAME);
                    $sender_email = Mage::getStoreConfig('trans_email/ident_general/email');
                    $email_template->setSenderName($sender_name);
                    $email_template->setSenderEmail($sender_email);
                    $email_template->send($email_to, $customer_name, $email_template_variables);

                }

                if (Mage::getStoreConfig('marketplace/product/addproductemailnotification') == 1) {
                    /**
                     *  Sending email for added new product
                     */
                    $templateId = (int)Mage::getStoreConfig('marketplace/product/addproductapprovalemailnotificationtemplate');
                    $adminEmailId = Mage::getStoreConfig('marketplace/marketplace/admin_email_id');
                    $toMailId = Mage::getStoreConfig("trans_email/ident_$adminEmailId/email");
                    $toName = Mage::getStoreConfig("trans_email/ident_$adminEmailId/name");

                    if ($templateId) {
                        $emailTemplate = Mage::getModel('core/email_template')->load($templateId);
                    } else {
                        $emailTemplate = Mage::getModel('core/email_template')
                            ->loadDefault('marketplace_product_addproductapprovalemailnotificationtemplate');
                    }
                    $customer = Mage::getModel('customer/customer')->load($sellerId);
                    $selleremail = $customer->getEmail();
                    $recipient = $toMailId;
                    $sellername = $customer->getName();
                    $productname = $product->getName();
                    $producturl = Mage::helper('adminhtml')->getUrl('adminhtml/catalog_product/edit', array('id' => $product->getId()));

                    $emailTemplate->setSenderName($sellername);
                    $emailTemplate->setSenderEmail($selleremail);
                    $emailTemplateVariables = (array('ownername' => $toName, 'sellername' => $sellername, 'selleremail' => $selleremail, 'productname' => $productname, 'producturl' => $producturl));
                    $emailTemplate->setDesignConfig(array('area' => 'frontend'));
                    $processedTemplate = $emailTemplate->getProcessedTemplate($emailTemplateVariables);
                    $emailTemplate->send($recipient, $sellername, $emailTemplateVariables);


                }
            }

            if ($type == 'configurable') {
                $this->_redirect('marketplace/product/configurable/', array('id' => $productId, 'set' => $set));
                return;
            }

            $this->_redirect('marketplace/product/manage/');
        } catch (Mage_Core_Exception $e) {
            /**
             *  Error message redirect to create new product page
             */
            Mage::getSingleton('core/session')->addError($this->__($e->getMessage()));
            $this->_redirect('marketplace/product/create/');
        } catch (Exception $e) {
            /**
             *  Error message redirect to create new product page
             */
            Mage::getSingleton('core/session')->addError($this->__($e->getMessage()));
            $this->_redirect('marketplace/product/create/');
        }
    } else {
        Mage::getSingleton('core/session')->addError($this->__('Please enter all required fields'));
        if ($type == 'configurable') {
            $this->_redirect('marketplace/product/selectattributes/', array('set' => $set));
            return;
        }
        $this->_redirect('marketplace/product/new');
    }
}    

config.xml

<catalog_product_save_after>
    <observers>
        <marketplace>
            <class>marketplace/observer</class>
            <method>sendme</method>
        </marketplace>
    </observers>
</catalog_product_save_after>

Observer.php

public function sendme($observer)
{
    $mail = Mage::getModel('core/email');
    $mail->setToName('User');
    $mail->setToEmail('testmail98@gmail.com');
    $mail->setBody('Send Test mail to you.....');
    $mail->setSubject('Test Mail');
    $mail->setFromEmail('testmail@gmail.com');
    $mail->setFromName("Send Test mail to you.....");
    $mail->setType('html');// YOu can use Html or text as Mail format
    $mail->send();
}

Error

SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry
'16958-1' for key
'UNQ_CATALOGINVENTORY_STOCK_ITEM_PRODUCT_ID_STOCK_ID', query was:
INSERT INTO cataloginventory_stock_item (product_id, stock_id,
qty, is_in_stock, low_stock_date, stock_status_changed_auto)
VALUES (?, ?, ?, ?, ?, ?)

is it right or Suggest me