/* =========================================================
   AJAX SAVE TRAINING
========================================================= */

add_action('wp_ajax_gmrtc_save_training', 'gmrtc_save_training');
function gmrtc_save_training() {

    check_ajax_referer('gmrtc_secure_nonce', 'nonce');

    if ( ! current_user_can('manage_options') ) {
        wp_send_json_error(array('message' => 'Unauthorized.'));
    }

    global $wpdb;

    $table = $wpdb->prefix . 'gmrtc_trn_db';

    $allowed_status = array(
        'Template',
        'Listed',
        'Private',
        'Started',
        'Finished',
        'Cancelled'
    );

    $trn_status = sanitize_text_field($_POST['trn_status']);

    if ( ! in_array($trn_status, $allowed_status) ) {
        wp_send_json_error(array('message' => 'Invalid Training Status.'));
    }

    $data = array(
        'trn_id' => sanitize_text_field($_POST['trn_id']),
        'trn_status' => $trn_status,
        'trn_title' => sanitize_text_field($_POST['trn_title']),
        'trn_company' => sanitize_text_field($_POST['trn_company']),
        'trn_lang' => sanitize_text_field($_POST['trn_lang']),
        'trn_class' => sanitize_text_field($_POST['trn_class']),
        'trn_expertise' => sanitize_text_field($_POST['trn_expertise']),
        'trn_posterlink' => esc_url_raw($_POST['trn_posterlink']),
        'trn_venue' => sanitize_text_field($_POST['trn_venue']),
        'trn_slogan' => sanitize_text_field($_POST['trn_slogan']),
        'trn_outcomes' => wp_kses_post($_POST['trn_outcomes']),
        'trn_explanation' => wp_kses_post($_POST['trn_explanation']),
        'trn_startdate' => sanitize_text_field($_POST['trn_startdate']),
        'trn_enddate' => sanitize_text_field($_POST['trn_enddate']),
        'trn_duration' => intval($_POST['trn_duration']),
        'trn_listingdate' => sanitize_text_field($_POST['trn_listingdate']),
        'trn_discenddate' => sanitize_text_field($_POST['trn_discenddate']),
        'trn_discountrat' => floatval($_POST['trn_discountrat']),
        'trn_fee_usd' => floatval($_POST['trn_fee_usd']),
        'trn_fee_try' => floatval($_POST['trn_fee_try']),
        'trn_quota' => intval($_POST['trn_quota']),
        'trn_validity' => intval($_POST['trn_validity']),
        'trn_inst_id1' => sanitize_text_field($_POST['trn_inst_id1']),
        'trn_inst_id2' => sanitize_text_field($_POST['trn_inst_id2']),
        'cert_bg_attendance' => esc_url_raw($_POST['cert_bg_attendance']),
        'cert_bg_bronze' => esc_url_raw($_POST['cert_bg_bronze']),
        'cert_bg_silver' => esc_url_raw($_POST['cert_bg_silver']),
        'cert_bg_gold' => esc_url_raw($_POST['cert_bg_gold']),
        'cert_text_attendance' => wp_kses_post($_POST['cert_text_attendance']),
        'cert_text_bronze' => wp_kses_post($_POST['cert_text_bronze']),
        'cert_text_silver' => wp_kses_post($_POST['cert_text_silver']),
        'cert_text_gold' => wp_kses_post($_POST['cert_text_gold']),
        'trn_canceldate' => sanitize_text_field($_POST['trn_canceldate']),
        'trn_cancelreason' => sanitize_text_field($_POST['trn_cancelreason']),
        'updated_at' => current_time('mysql')
    );

    $db_id = intval($_POST['db_id']);

    if ( empty($db_id) ) {

        $data['created_at'] = current_time('mysql');
        $data['ip_address'] = $_SERVER['REMOTE_ADDR'];

        $exists = $wpdb->get_var(
            $wpdb->prepare(
                "SELECT COUNT(*) FROM $table WHERE trn_id = %s",
                $data['trn_id']
            )
        );

        if ( $exists ) {
            wp_send_json_error(array('message' => 'Training ID already exists.'));
        }

        $insert = $wpdb->insert($table, $data);

        if ( ! $insert ) {
            wp_send_json_error(array('message' => 'Database insert failed.'));
        }

        wp_send_json_success(array(
            'message' => 'Training created successfully.'
        ));

    } else {

        $update = $wpdb->update(
            $table,
            $data,
            array('id' => $db_id)
        );

        if ( $update === false ) {
            wp_send_json_error(array('message' => 'Database update failed.'));
        }

        wp_send_json_success(array(
            'message' => 'Training updated successfully.'
        ));
    }
}

/* =========================================================
   AJAX SAVE PARTICIPANT
========================================================= */

add_action('wp_ajax_gmrtc_save_participant', 'gmrtc_save_participant');
function gmrtc_save_participant() {

    check_ajax_referer('gmrtc_secure_nonce', 'nonce');

    if ( ! current_user_can('manage_options') ) {
        wp_send_json_error(array('message' => 'Unauthorized.'));
    }

    global $wpdb;

    $allowed = array(
        'Awaiting Attendance',
        'Participated',
        'Certified',
        'Removed',
        'Cancelled'
    );

    $participant_status = sanitize_text_field($_POST['participant_status']);

    if ( ! in_array($participant_status, $allowed) ) {
        wp_send_json_error(array('message' => 'Invalid Participant Status.'));
    }

    $updated = $wpdb->update(
        $wpdb->prefix . 'gmrtc_ptcp_db',
        array(
            'participant_status' => $participant_status,
            'updated_at' => current_time('mysql')
        ),
        array(
            'id' => intval($_POST['db_id'])
        )
    );

    if ( $updated === false ) {
        wp_send_json_error(array('message' => 'Participant update failed.'));
    }

    wp_send_json_success(array(
        'message' => 'Participant updated successfully.'
    ));
}

/* =========================================================
   AJAX DELETE RECORD
========================================================= */

add_action('wp_ajax_gmrtc_delete_record', 'gmrtc_delete_record');
function gmrtc_delete_record() {

    check_ajax_referer('gmrtc_secure_nonce', 'nonce');

    if ( ! current_user_can('manage_options') ) {
        wp_send_json_error(array('message' => 'Unauthorized.'));
    }

    global $wpdb;

    $db_id = intval($_POST['db_id']);
    $table_type = sanitize_text_field($_POST['table_type']);

    $allowed = array(
        'trn_db',
        'preg_db',
        'ptcp_db',
        'cert_db'
    );

    if ( ! in_array($table_type, $allowed) ) {
        wp_send_json_error(array('message' => 'Invalid table.'));
    }

    $table = $wpdb->prefix . 'gmrtc_' . $table_type;

    $deleted = $wpdb->delete(
        $table,
        array('id' => $db_id)
    );

    if ( ! $deleted ) {
        wp_send_json_error(array('message' => 'Delete failed.'));
    }

    wp_send_json_success(array(
        'message' => 'Record archived successfully.'
    ));
}

/* =========================================================
   AJAX APPROVE PREREGISTRATION
========================================================= */

add_action('wp_ajax_gmrtc_approve_preg', 'gmrtc_approve_preg');
function gmrtc_approve_preg() {

    check_ajax_referer('gmrtc_secure_nonce', 'nonce');

    if ( ! current_user_can('manage_options') ) {
        wp_send_json_error(array('message' => 'Unauthorized.'));
    }

    global $wpdb;

    $preg_table = $wpdb->prefix . 'gmrtc_preg_db';
    $ptcp_table = $wpdb->prefix . 'gmrtc_ptcp_db';

    $db_id = intval($_POST['db_id']);

    $record = $wpdb->get_row(
        $wpdb->prepare(
            "SELECT * FROM $preg_table WHERE id = %d",
            $db_id
        )
    );

    if ( ! $record ) {
        wp_send_json_error(array('message' => 'Record not found.'));
    }

    $insert = $wpdb->insert(
        $ptcp_table,
        array(
            'ptcp_id' => $record->ptcp_id,
            'participant_status' => 'Awaiting Attendance',
            'trn_id' => $record->trn_id,
            'trn_title' => $record->trn_title,
            'ptcp_name' => $record->ptcp_name,
            'ptcp_surname' => $record->ptcp_surname,
            'ptcp_email' => $record->ptcp_email,
            'ptcp_tel' => $record->ptcp_tel,
            'ptcp_address' => $record->ptcp_address,
            'ptcp_province' => $record->ptcp_province,
            'ptcp_country' => $record->ptcp_country,
            'ptcp_bill_type' => $record->ptcp_bill_type,
            'ptcp_tax_office' => $record->ptcp_tax_office,
            'ptcp_nat_id' => $record->ptcp_nat_id,
            'ptcp_organization' => $record->ptcp_organization,
            'ptcp_jobtitle' => $record->ptcp_jobtitle,
            'accepted_at' => current_time('mysql'),
            'created_at' => current_time('mysql'),
            'updated_at' => current_time('mysql')
        )
    );

    if ( ! $insert ) {
        wp_send_json_error(array('message' => 'Transfer failed.'));
    }

    $wpdb->update(
        $preg_table,
        array(
            'ptcp_status' => 'Approved',
            'updated_at' => current_time('mysql')
        ),
        array(
            'id' => $db_id
        )
    );

    wp_send_json_success(array(
        'message' => 'Participant transferred successfully.'
    ));
}

/* =========================================================
   AJAX REJECT PREREGISTRATION
========================================================= */

add_action('wp_ajax_gmrtc_reject_preg', 'gmrtc_reject_preg');
function gmrtc_reject_preg() {

    check_ajax_referer('gmrtc_secure_nonce', 'nonce');

    if ( ! current_user_can('manage_options') ) {
        wp_send_json_error(array('message' => 'Unauthorized.'));
    }

    global $wpdb;

    $updated = $wpdb->update(
        $wpdb->prefix . 'gmrtc_preg_db',
        array(
            'ptcp_status' => 'Rejected',
            'updated_at' => current_time('mysql')
        ),
        array(
            'id' => intval($_POST['db_id'])
        )
    );

    if ( $updated === false ) {
        wp_send_json_error(array('message' => 'Reject failed.'));
    }

    wp_send_json_success(array(
        'message' => 'Preregistration rejected.'
    ));
}

/* =========================================================
   CERTIFICATE SAVE SYSTEM
========================================================= */

add_action('wp_ajax_gmrtc_save_certification', 'gmrtc_save_certification');
function gmrtc_save_certification() {

    check_ajax_referer('gmrtc_secure_nonce', 'nonce');

    if ( ! current_user_can('manage_options') ) {
        wp_send_json_error(array('message' => 'Unauthorized.'));
    }

    global $wpdb;

    $cert_table = $wpdb->prefix . 'gmrtc_cert_db';
    $ptcp_table = $wpdb->prefix . 'gmrtc_ptcp_db';

    $db_id = intval($_POST['db_id']);

    $grade = floatval($_POST['certification_grade']);

    if($grade < 0) $grade = 0;
    if($grade > 100) $grade = 100;

    $level = sanitize_text_field($_POST['achieved_level']);

    $allowed_levels = array(
        'Participant',
        'Bronze',
        'Silver',
        'Gold'
    );

    if(!in_array($level, $allowed_levels)){
        $level = 'Participant';
    }

    if(empty($db_id)){

        do {

            $cert_no = 'CERT-' . mt_rand(10000000,99999999);

            $exists = $wpdb->get_var(
                $wpdb->prepare(
                    "SELECT COUNT(*) FROM $cert_table WHERE cert_no = %s",
                    $cert_no
                )
            );

        } while($exists);

    } else {

        $existing = $wpdb->get_row(
            $wpdb->prepare(
                "SELECT * FROM $cert_table WHERE id = %d",
                $db_id
            )
        );

        $cert_no = $existing->cert_no;

    }

    $verify_token = wp_generate_password(64,false,false);

    $data = array(

        'cert_no' => $cert_no,

        'ptcp_id' => sanitize_text_field($_POST['ptcp_id']),
        'trn_id' => sanitize_text_field($_POST['trn_id']),

        'ptcp_test1weight' => floatval($_POST['ptcp_test1weight']),
        'ptcp_test1grade' => floatval($_POST['ptcp_test1grade']),

        'ptcp_test2weight' => floatval($_POST['ptcp_test2weight']),
        'ptcp_test2grade' => floatval($_POST['ptcp_test2grade']),

        'ptcp_test3weight' => floatval($_POST['ptcp_test3weight']),
        'ptcp_test3grade' => floatval($_POST['ptcp_test3grade']),

        'ptcp_bonus1pts' => floatval($_POST['ptcp_bonus1pts']),
        'ptcp_bonus2pts' => floatval($_POST['ptcp_bonus2pts']),
        'ptcp_bonus3pts' => floatval($_POST['ptcp_bonus3pts']),

        'certification_grade' => $grade,
        'achieved_level' => $level,

        'issue_date' => sanitize_text_field($_POST['issue_date']),
        'valid_until' => sanitize_text_field($_POST['valid_until']),

        'cert_status' => sanitize_text_field($_POST['cert_status']),

        'verify_token' => $verify_token,

        'updated_at' => current_time('mysql')

    );

    if(empty($db_id)){

        $data['created_at'] = current_time('mysql');

        $insert = $wpdb->insert($cert_table,$data);

        if(!$insert){

            wp_send_json_error(array(
                'message' => 'Certificate insert failed.'
            ));

        }

    } else {

        $update = $wpdb->update(
            $cert_table,
            $data,
            array(
                'id' => $db_id
            )
        );

        if($update === false){

            wp_send_json_error(array(
                'message' => 'Certificate update failed.'
            ));

        }

    }

    $wpdb->update(
        $ptcp_table,
        array(
            'participant_status' => 'Certified',
            'updated_at' => current_time('mysql')
        ),
        array(
            'ptcp_id' => sanitize_text_field($_POST['ptcp_id'])
        )
    );

    wp_send_json_success(array(
        'message' => 'Certification saved successfully.',
        'cert_no' => $cert_no
    ));

}

/* =========================================================
   GENERATE PDF + QR
========================================================= */

add_action('wp_ajax_gmrtc_generate_pdf', 'gmrtc_generate_pdf');
function gmrtc_generate_pdf() {

    check_ajax_referer('gmrtc_secure_nonce', 'nonce');

    if ( ! current_user_can('manage_options') ) {
        wp_send_json_error(array('message' => 'Unauthorized.'));
    }

    global $wpdb;

    require_once get_stylesheet_directory() . '/gmrtc-system/tcpdf/tcpdf.php';

    $db_id = intval($_POST['db_id']);

    $cert = $wpdb->get_row(
        $wpdb->prepare(
            "SELECT * FROM {$wpdb->prefix}gmrtc_cert_db WHERE id = %d",
            $db_id
        )
    );

    if(!$cert){

        wp_send_json_error(array(
            'message' => 'Certificate record not found.'
        ));

    }

    $participant = $wpdb->get_row(
        $wpdb->prepare(
            "SELECT * FROM {$wpdb->prefix}gmrtc_ptcp_db WHERE ptcp_id = %s",
            $cert->ptcp_id
        )
    );

    $training = $wpdb->get_row(
        $wpdb->prepare(
            "SELECT * FROM {$wpdb->prefix}gmrtc_trn_db WHERE trn_id = %s",
            $cert->trn_id
        )
    );

    if(!$participant || !$training){

        wp_send_json_error(array(
            'message' => 'Participant or Training missing.'
        ));

    }

    $pdf = new TCPDF('L','mm','A4',true,'UTF-8',false);

    $pdf->SetCreator('GMRTC');
    $pdf->SetAuthor('GMRTC');
    $pdf->SetTitle($cert->cert_no);

    $pdf->setPrintHeader(false);
    $pdf->setPrintFooter(false);

    $pdf->SetMargins(0,0,0);

    $pdf->AddPage();

    $bg = '';

    if($cert->achieved_level === 'Gold'){
        $bg = $training->cert_bg_gold;
        $text_template = $training->cert_text_gold;
    }

    elseif($cert->achieved_level === 'Silver'){
        $bg = $training->cert_bg_silver;
        $text_template = $training->cert_text_silver;
    }

    elseif($cert->achieved_level === 'Bronze'){
        $bg = $training->cert_bg_bronze;
        $text_template = $training->cert_text_bronze;
    }

    else{
        $bg = $training->cert_bg_attendance;
        $text_template = $training->cert_text_attendance;
    }

    if(!empty($bg)){

        $pdf->Image($bg,0,0,297,210,'','','',false,300);

    }

    $full_name = $participant->ptcp_name . ' ' . $participant->ptcp_surname;

    $verify_url = add_query_arg(array(
        'verify_cert' => $cert->verify_token
    ), home_url('/'));

    $text_template = str_replace(
        array(
            '{FULLNAME}',
            '{TRAINING}',
            '{GRADE}',
            '{LEVEL}',
            '{CERTNO}'
        ),
        array(
            $full_name,
            $training->trn_title,
            $cert->certification_grade,
            $cert->achieved_level,
            $cert->cert_no
        ),
        $text_template
    );

    $pdf->SetFont('helvetica','',18);

    $pdf->SetTextColor(20,20,20);

    $pdf->SetXY(25,80);

    $pdf->MultiCell(
        245,
        10,
        $text_template,
        0,
        'C',
        false,
        1
    );

    $pdf->write2DBarcode(
        $verify_url,
        'QRCODE,H',
        240,
        150,
        35,
        35
    );

    $pdf->SetFont('helvetica','',9);

    $pdf->SetXY(200,190);

    $pdf->Cell(
        80,
        5,
        $cert->cert_no,
        0,
        0,
        'R'
    );

    $upload_dir = wp_upload_dir();

    $cert_dir = $upload_dir['basedir'] . '/gmrtc-certificates';

    if(!file_exists($cert_dir)){

        wp_mkdir_p($cert_dir);

    }

    $filename = sanitize_file_name($cert->cert_no . '.pdf');

    $filepath = $cert_dir . '/' . $filename;

    $fileurl = $upload_dir['baseurl'] . '/gmrtc-certificates/' . $filename;

    $pdf->Output($filepath,'F');

    $wpdb->update(
        $wpdb->prefix . 'gmrtc_cert_db',
        array(
            'pdf_url' => $fileurl,
            'updated_at' => current_time('mysql')
        ),
        array(
            'id' => $db_id
        )
    );

    wp_send_json_success(array(
        'message' => 'Certificate generated successfully.',
        'pdf_url' => $fileurl
    ));

}

/* =========================================================
   CERTIFICATE VERIFY PAGE
========================================================= */

add_action('init','gmrtc_certificate_verify_router');

function gmrtc_certificate_verify_router(){

    if(!isset($_GET['verify_cert'])){
        return;
    }

    global $wpdb;

    $token = sanitize_text_field($_GET['verify_cert']);

    $cert = $wpdb->get_row(
        $wpdb->prepare(
            "SELECT * FROM {$wpdb->prefix}gmrtc_cert_db WHERE verify_token = %s",
            $token
        )
    );

    if(!$cert){

        wp_die('Certificate not found.');

    }

    $month_key = 'gmrtc_cert_views_' . md5($cert->cert_no . date('Ym'));

    $views = intval(get_transient($month_key));

    if($views >= 50){

        wp_die('Monthly certificate display limit exceeded.');

    }

    set_transient(
        $month_key,
        ($views + 1),
        MONTH_IN_SECONDS
    );

    if(empty($cert->pdf_url)){

        wp_die('Certificate PDF missing.');

    }

    wp_redirect($cert->pdf_url);

    exit;

}