PHP Multiple input search to query mysql database - php

Question

I'm trying to query Mysql with a form with multiple input search but for some reason, in the end, nothing come out.
I'm using some code that I found here on stack - PHP Multiple input search
Here my html form
<form id="SearchFlightForm" method="post" action="searchresult.php" accept-charset='UTF-8'>
<div class="col-md-12 product-search-title">Search For Flights Deals </div>
<div class="col-md-12 search-col-padding">
<label class="radio-inline">
<input type="radio" name="inlineradiooptions" id="inlineRadio1" value="One Way"> One Way</label>
<label class="radio-inline">
<input type="radio" name="inlineradiooptions" id="inlineRadio2" value="Round Trip"> Round Trip</label>
</div>
<div class="clearfix"></div>
<div class="col-md-6 col-sm-6 search-col-padding">
<label>Leaving From</label>
<div class="input-group">
<input type="text" name="departure_city" class="form-control" required placeholder="E.g. London">
<span class="input-group-addon"><i class="fa fa-map-marker fa-fw"></i></span></div></div>
<div class="col-md-6 col-sm-6 search-col-padding">
<label>Leaving To</label>
<div class="input-group">
<input type="text" name="destination_city" class="form-control" required placeholder="E.g. New York">
<span class="input-group-addon"><i class="fa fa-map-marker fa-fw"></i></span></div></div>
<div class="clearfix"></div>
<div class="col-md-6 col-sm-6 search-col-padding">
<label>Departure</label>
<div class="input-group">
<input type="text" id="departure_date" name="departure_date" class="form-control" placeholder="DD/MM/YYYY">
<span class="input-group-addon"><i class="fa fa-calendar fa-fw"></i></span>
</div>
</div>
<div class="col-md-6 col-sm-6 search-col-padding">
<label>Return</label>
<div class="input-group">
<input type="text" id="return_date" class="form-control" name="return_date" placeholder="DD/MM/YYYY">
<span class="input-group-addon"><i class="fa fa-calendar fa-fw"></i></span>
</div>
</div>
<div class="clearfix"></div>
<div class="col-md-3 col-sm-3 search-col-padding">
<label>Adult</label><br>
<input id="adult_count" name="adult_count" value="1" class="form-control quantity-padding">
</div>
<div class="col-md-3 col-sm-3 search-col-padding">
<label>Child</label><br>
<input type="text" id="child_count" name="child_count" value="0" class="form-control quantity-padding">
</div>
<div class="col-md-3 col-sm-3 search-col-padding">
<label>Infants</label><br>
<select class="selectpicker" name="infants">
<option value="0">0</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
</select>
</div>
<div class="col-md-3 col-sm-3 search-col-padding">
<label>Class</label><br>
<select class="selectpicker" name="flightclass">
<option value="economy">Economy</option>
<option value="business">Business</option>
</select>
</div>
<div class="clearfix"></div>
<div class="col-md-12 search-col-padding">
<button type="submit" name="submit" id="submit" class="search-button btn transition-effect">Search Flights</button>
</div>
<div class="clearfix"></div>
</form>
Here the action file
<?php
// Process the search query
include('ligacaoBD.php');
if(isset($_POST['submit'])) {
// define the list of fields
$fields = array('id', 'inlineradiooptions', 'departure_city', 'destination_city',
'departure_date', 'return_date', 'adult_count', 'child_count', 'infants', 'flightclass');
$conditions = array();
}
// builds the query
$query = "SELECT id, airline_image, flight_class, departure_date, departure_time, departure_location, arrival_date, arrival_time, arrival_location, flight_stops, flight_duration FROM flight_details WHERE id=1";
// if there are conditions defined
if(count($conditions) > 0) {
// append the conditions
$query .= " WHERE " . implode (' AND ', $conditions); // you can change to 'OR', but I suggest to apply the filters cumulative
}
// loop through the defined fields
foreach($fields as $field){
// if the field is set and not empty
if(isset($_POST[$field]) && $_POST[$field] != '') {
// create a new condition while escaping the value inputed by the user (SQL Injection)
$conditions[] = "'$field' LIKE '%" . mysqli_real_escape_string($mysqli_link, $_POST[$field]) . "%'";
}
}
// if there are conditions defined
if(count($conditions) > 0) {
// append the conditions
$query .= " WHERE " . implode (' AND ', $conditions); // you can change to 'OR', but I suggest to apply the filters cumulative
}
$result = mysqli_query($mysqli_link, $query);
mysqli_close($mysqli_link);
if(isset($_POST['submit'])) {
while($row = mysqli_fetch_array($result)) {
$id = $row['id'];
$flight_image = $row['flight_image'];
$flight_class = $row['flight_class'];
$departure_date = $row['departure_date'];
$departure_time = $row['departure_time'];
$departure_location = $row['departure_location'];
$arrival_date = $row['arrival_date'];
$arrival_time = $row['arrival_time'];
$arrival_location = $row['arrival_location'];
$flight_stops = $row['flight_stops'];
$flight_duration = $row['flight_duration'];
echo "<b>id: $id</b><br> image: $flight_image<br>Class: $flightclass<br>departure_date: $departure_date<br>departure_time: $departure_time<br>departure_location: $departure_location<br>arrival_date: $arrival_date<br>arrival_time: $arrival_time<br>arrival_location: $arrival_location<br>flight_stops: $flight_stops<br>flight_duration: $flight_duration<hr><br>";
}
}
?>
Please could anyone give a hint of what I'm doing wrong.
thanks S.C