Fixed: data validation in offline refuel create form

Updated:
- DashboardController now fetches latest refuel record only for the default vehicle
- VehicleController - first created vehicle is now set as default automatically
- Refuel model - latest_one() now accepts vehicle_id instead of user_id
- Dashboard view - improved handling when no vehicles or refuel records exist
- CSS styles - adjusted dashboard layout and global action padding

README.md

@@ -53,5 +53,13 @@ php -S localhost:8000 -t ./public
 4. Track your fuel consumption and spending through the dashboard.
 5. View detailed stats and graphs to analyze your driving habits.
 
+## Use case diagram
+![](.screenshots/usecase.png)
+## Data logical model
+![](.screenshots/dlm.png)
+
+## Class diagram
+![](.screenshots/class.png)
+
 ## License
 This project is licensed under GPL3.0 and later. More information is available in the `LICENSE` file.

TODO.md

@@ -7,17 +7,38 @@
 
 ## Core of the app
 - [ ] intro tutorial when no car exist or just dont show anything
-- [ ] change/set default car
+- [x] change/set default car
 - [ ] specific car view - charts, fuel records
 - [ ] remove/edit fuel record
 
 ## Until release
-- [ ] Sync offline data from locale storage
-- [ ] Include kilometer state of an car
+- [x] Sync offline data from locale storage
+- [x] Include kilometer state of an car
 - [ ] More charts
-  - [ ] Average fuel conusption
+  - [x] Average fuel conusption
   - [ ] Kilometer state
 - [ ] More cards
   - [ ] Average fuel conusption in last 30 days
   - [ ] Kilometer state in last 30 days`
 - [ ] Offline navigation between dashboard and offline form
+
+## What has to be done
+- [x] Vehicle delete
+- [ ] intro tutorial when no car exist or just dont show anything
+- [x] change/set default car
+- [x] hide errors
+
+## Nice to have
+- [ ] specific car view - charts, fuel records
+- [ ] remove/edit fuel record
+- [x] Include kilometer state of an car
+- [ ] More charts
+  - [x] Average fuel conusption
+  - [ ] Kilometer state
+- [ ] More cards
+  - [ ] Average fuel conusption in last 30 days
+  - [ ] Kilometer state in last 30 days`
+- [ ] Offline navigation between dashboard and offline form
+- [ ] Fix vehicle deletion - wrong redirect
+- [ ] Update diagrams in README.md
+

app/controllers/DashboardController.php

@@ -3,29 +3,25 @@ class DashboardController extends Controller {
     public function index() {
         $vehicle = new Vehicle();
         $vehicles = $vehicle->getVehiclesByUser($_SESSION['user']['id']);
-
-        $default_car = $vehicle->getDefaultVehicle($_SESSION['user']['id']);
+        $default_car = $vehicle->getDefaultVehicle($_SESSION['user']['id']) ?? null;
 
         $refuel = new Refuel();
         $data = [
             "date" => [],
             "price" => [],
+            "mileage" => [],
+            "liters" => []
         ];
-        $raw_data = $refuel->latest_data($default_car['id'], 5);
+        $raw_data = $default_car ? $refuel->latest_data($default_car['id'], 0) : [];
         foreach($raw_data as $one) {
             array_push($data['date'], date('d. m.', strtotime($one['created_at'])));
             array_push($data['price'], $one['price_per_liter']);
+            array_push($data['mileage'], $one['mileage']);
+            array_push($data['liters'], $one['liters']);
         }
 
-        $latest_record = [
-            'name',
-            'liters',
-            'price_per_liter',
-            'total_price',
-            'created_at'
-        ];
-
-        $latest_record = $refuel->latest_one($_SESSION['user']['id'])[0];
+        $latest_data = $default_car ? $refuel->latest_one($default_car['id']) : [];
+        $latest_record = !empty($latest_data) ? $latest_data[0] : null;
 
         $this->view('dashboard/index', [
             'title' => 'Dashboard',

app/controllers/RefuelController.php

@@ -18,6 +18,7 @@ class RefuelController extends Controller {
             $liters = $_POST['liters'] ?? '';
             $price_per_liter = $_POST['price_per_liter'] ?? '';
             $total_price = $_POST['total_price'] ?? '';
+            $mileage = $_POST['mileage'] ?? '';
             $note = $_POST['note'] ?? '';
 
             $validator = new Validator();
@@ -29,6 +30,7 @@ class RefuelController extends Controller {
             $validator->number('liters', $liters);
             $validator->number('price_per_liter', $price_per_liter);
             $validator->number('total_price', $total_price);
+            $validator->number('mileage', $mileage);
 
             if (round($liters * $price_per_liter, 2) != $total_price) {
                 $validator->setErrors(["total_price" => "Price calculation is wrong"]);
@@ -44,6 +46,7 @@ class RefuelController extends Controller {
                     'validationErrors' => $validator->errors() ?: [],
                     'vehicles' => $vehicles,
                     'title' => 'New refuel record',
+                    'status' => '400'
                 ]);
                 return;
             }
@@ -57,6 +60,7 @@ class RefuelController extends Controller {
                 'liters' => $liters,
                 'price_per_liter' => $price_per_liter,
                 'total_price' => $total_price,
+                'mileage' => $mileage,
             ]);
 
             if ($result === true) {

app/controllers/VehicleController.php

@@ -30,17 +30,21 @@ class VehicleController extends Controller {
             }
 
             $vehicle = new Vehicle();
+            $default_vehicle = $vehicle->getDefaultVehicle($_SESSION['user']['id']);
+            $is_default = $default_vehicle ? 0 : 1;
+
             $result = $vehicle->create([
                 'name' => $name,
                 'registration_plate' => strtoupper($registration_plate),
                 'fuel_type' => $fuel_type,
                 'note' => $note,
                 'user_id' => $_SESSION['user']['id'],
+                'is_default' => $is_default
             ]);
 
 
             if ($result === true) {
-                $this->redirect('/vehicles');
+                $this->redirect('/');
             } else {
                 $this->view('vehicles/create', ['title' => 'Create vehicle', 'error' => $result, 'validationErrors' => []] );
             }
@@ -56,7 +60,35 @@ class VehicleController extends Controller {
     }
 
     public function delete() {
-        // TODO: Delete vehicle (to be implemented later)
+        if(!$_SERVER['REQUEST_METHOD'] === 'POST') {
+            echo "Wrong method";
+            return;
+        }
+
+        // TODO: Validate the request
+        $vehicle_id = $_POST['vehicle_id'];
+
+        $vehicle = new Vehicle();
+        $result = $vehicle->delete($vehicle_id, $_SESSION['user']['id']);
+
+        if($result != true) {
+            echo "Something went wrong";
+            return;
+        }
+
+        header("Location: /vehicles");
+    }
+
+    public function setDefault() {
+        $vehicle = new Vehicle();
+        // TODO: Validate the request
+        $result = $vehicle->setDefaultVehicle($_POST['vehicle_id'], $_SESSION['user']['id']);
+        if($result != true) {
+            echo "Something went wrong";
+            return;
+        }
+
+        header("Location: /");
     }
 
     public function api_get() {

app/models/Refuel.php

@@ -10,12 +10,12 @@ class Refuel {
     public function create($data) {
         try{
             $stmt = $this->db->prepare("
-                INSERT INTO refueling_records (user_id, vehicle_id, fuel_type, note, liters, price_per_liter, total_price, created_at)
-                VALUES (?, ?, ?, ?, ?, ?, ?, NOW())
+                INSERT INTO refueling_records (user_id, vehicle_id, fuel_type, note, liters, price_per_liter, total_price, mileage, created_at)
+                VALUES (?, ?, ?, ?, ?, ?, ?, ?, NOW())
             ");
 
             $stmt->bind_param(
-                "iissddd",
+                "iissdddi",
                 $data['user_id'],
                 $data['vehicle_id'],
                 $data['fuel_type'],
@@ -23,6 +23,7 @@ class Refuel {
                 $data['liters'],
                 $data['price_per_liter'],
                 $data['total_price'],
+                $data['mileage'],
             );
 
             if ($stmt->execute()) {
@@ -37,15 +38,24 @@ class Refuel {
 
     public function latest_data($vehicle_id, $record_count) {
         try {
-            $stmt = $this->db->prepare("
-                SELECT `liters`, `price_per_liter`, `total_price`, `created_at`
+            $sql = "
+                SELECT `liters`, `price_per_liter`, `total_price`, `mileage`, `created_at`
                 FROM `refueling_records`
                 WHERE `vehicle_id` = ?
-                ORDER BY created_at DESC
-                LIMIT ?;
-            ");
+                ORDER BY created_at DESC";
+
+            if ($record_count > 0) {
+                $sql .= " LIMIT ?";
+            }
+
+            $stmt = $this->db->prepare($sql);
+
+            if ($record_count > 0) {
+                $stmt->bind_param("ii", $vehicle_id, $record_count);
+            } else {
+                $stmt->bind_param("i", $vehicle_id);
+            }
 
-            $stmt->bind_param("ii", $vehicle_id, $record_count);
             if ($stmt->execute()) {
                 $result = $stmt->get_result();
                 $data = $result->fetch_all(MYSQLI_ASSOC);
@@ -59,24 +69,35 @@ class Refuel {
         }
     }
 
-    public function latest_one($user_id, $record_count = 1) {
+    public function latest_one($vehicle_id, $record_count = 1) {
         try {
-            $stmt = $this->db->prepare("
+            $sql = "
                 SELECT 
                     `r`.`vehicle_id`, 
                     `v`.`name` AS `vehicle_name`, 
                     `r`.`liters`, 
                     `r`.`price_per_liter`, 
                     `r`.`total_price`, 
+                    `r`.`mileage`, 
+                    `r`.`note`, 
                     `r`.`created_at`
                 FROM `refueling_records` AS `r`
                 JOIN `vehicles` AS `v` ON `r`.`vehicle_id` = `v`.`id`
-                WHERE `r`.`user_id` = ?
-                ORDER BY `r`.`created_at` DESC
-                LIMIT ?;
-            ");
+                WHERE `r`.`vehicle_id` = ?
+                ORDER BY `r`.`created_at` DESC";
+
+            if ($record_count > 0) {
+                $sql .= " LIMIT ?";
+            }
+
+            $stmt = $this->db->prepare($sql);
+
+            if ($record_count > 0) {
+                $stmt->bind_param("ii", $vehicle_id, $record_count);
+            } else {
+                $stmt->bind_param("i", $vehicle_id);
+            }
 
-            $stmt->bind_param("ii", $user_id, $record_count);
             if ($stmt->execute()) {
                 $result = $stmt->get_result();
                 $data = $result->fetch_all(MYSQLI_ASSOC);

app/models/User.php

@@ -29,7 +29,7 @@ class User {
 
         $hashedPassword = password_hash($password, PASSWORD_BCRYPT);
 
-        $stmt = $this->db->prepare("INSERT INTO users (username, email, password, points, created_at) VALUES (?, ?, ?, 0, NOW())");
+        $stmt = $this->db->prepare("INSERT INTO users (username, email, password, created_at) VALUES (?, ?, ?, NOW())");
         $stmt->bind_param("sss", $username, $email, $hashedPassword);
 
         if ($stmt->execute()) {

app/models/Vehicle.php

@@ -10,17 +10,18 @@ class Vehicle {
     public function create($data) {
         try{
             $stmt = $this->db->prepare("
-                INSERT INTO vehicles (user_id, name, registration_plate, fuel_type, note, created_at)
-                VALUES (?, ?, ?, ?, ?, NOW())
+                INSERT INTO vehicles (user_id, name, registration_plate, fuel_type, note, is_default, created_at)
+                VALUES (?, ?, ?, ?, ?, ?, NOW())
             ");
 
             $stmt->bind_param(
-                "issss",
+                "issssi",
                 $data['user_id'],
                 $data['name'],
                 $data['registration_plate'],
                 $data['fuel_type'],
                 $data['note'],
+                $data['is_default'],
             );
 
             if ($stmt->execute()) {
@@ -34,7 +35,7 @@ class Vehicle {
     }
 
     public function getVehiclesByUser($user_id) {
-        $stmt = $this->db->prepare("SELECT id, name, registration_plate, fuel_type, note, created_at FROM vehicles WHERE user_id = ?");
+        $stmt = $this->db->prepare("SELECT id, name, registration_plate, fuel_type, note, is_default, created_at FROM vehicles WHERE user_id = ?");
         $stmt->bind_param("i", $user_id);
         $stmt->execute();
         $result = $stmt->get_result();
@@ -60,4 +61,61 @@ class Vehicle {
 
         return $result->fetch_assoc();
     }
+
+    public function setDefaultVehicle($vehicle_id, $user_id) {
+        try {
+            $this->db->begin_transaction();
+
+            $stmt = $this->db->prepare("
+                UPDATE `vehicles` 
+                SET `is_default` = 0 
+                WHERE `user_id` = ? AND `is_default` = 1
+            ");
+            $stmt->bind_param("i", $user_id);
+            $stmt->execute();
+            $stmt->close();
+
+            $stmt = $this->db->prepare("
+                UPDATE `vehicles` 
+                SET `is_default` = 1 
+                WHERE `id` = ? AND `user_id` = ?
+            ");
+            $stmt->bind_param("ii", $vehicle_id, $user_id);
+
+            if ($stmt->execute()) {
+                $this->db->commit();
+                return true;
+            } else {
+                $this->db->rollback();
+                return "Error: " . $stmt->error;
+            }
+        } catch (mysqli_sql_exception $e) {
+            $this->db->rollback();
+            return $e->getMessage();
+        }
+    }
+
+    public function delete($vehicle_id, $user_id) {
+        try {
+            $stmt = $this->db->prepare("SELECT id FROM vehicles WHERE id = ? AND user_id = ?");
+            $stmt->bind_param("ii", $vehicle_id, $user_id);
+            $stmt->execute();
+            $result = $stmt->get_result();
+
+            if ($result->num_rows === 0) {
+                return "Error: Unauthorized action or vehicle not found.";
+            }
+
+            $stmt = $this->db->prepare("DELETE FROM vehicles WHERE id = ?");
+            $stmt->bind_param("i", $vehicle_id);
+
+            if ($stmt->execute()) {
+                return true;
+            } else {
+                return "Error: " . $stmt->error;
+            }
+        } catch (mysqli_sql_exception $e) {
+            return $e->getMessage();
+        }
+    }
 }

app/views/dashboard/index.php

@@ -5,8 +5,15 @@
 
 <section class="dashboard">
     <h1>Welcome, <?= htmlspecialchars($_SESSION['user']['username']) ?>!</h1>
+    <?php if(!isset($data['default_car'])): ?>
+    
+    <div id="intro">
+        <a href="/vehicles/create">Create your first vehicle</a>
+    </div>
+    <?php elseif (isset($data['latest_record'])): ?>
+
     <div id="actions">
-        <a href="/refuel/create" class="btn-green">Add new refuel record!</a>
+        <a href="/refuel/create" class="btn-green">Add new refuel record</a>
         <a href="/vehicles" class="btn-primary">List all vehicles</a>
         <a class="btn-warning" id="btn-offline-add">Add new offline refuel record</a>
     </div>
@@ -23,6 +30,12 @@
                 <p><?= $data['latest_record']['price_per_liter'] ?>,-/liter</p>
                 <b>Total price:</b>
                 <p><?= $data['latest_record']['total_price'] ?>,-</p>
+                <b>Mileage:</b>
+                <p><?= $data['latest_record']['mileage'] ?> km</p>
+                <?php if (isset($data['latest_record']['note'])): ?>
+                <b>Note:</b>
+                <p><?= $data['latest_record']['note'] ?></p>
+                <?php endif; ?>
             </div>
         </section>
 
@@ -45,7 +58,25 @@
             <p><?= $data['default_car']['name'] . " | " . $data['default_car']['registration_plate']?></p>
             <canvas id="chart-gas-price"></canvas>
         </section>
+
+        <section class="card history-graph">
+            <h2>Average fuel consumption</h2>
+            <hr>
+            <p><?= $data['default_car']['name'] . " | " . $data['default_car']['registration_plate']?></p>
+            <b id="avg-fl-cnsmp"></b>
+        </section>
     </div>
+    <?php else: ?>
+    <div id="actions">
+        <a href="/refuel/create" class="btn-green">Add new refuel record</a>
+        <a href="/vehicles" class="btn-primary">List all vehicles</a>
+        <a class="btn-warning" id="btn-offline-add">Add new offline refuel record</a>
+    </div>
+    <div class="alert-warning">
+        <p>Default vehicle <b><i><?= $data['default_car']['name'] ?></i></b> doesn't have any refuel record yet.</p>
+        <p>Select another vehicle or create first refuel record.</p>
+    </div>
+    <?php endif; ?>
 </section>
 <script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
 <script>
@@ -64,4 +95,29 @@
         },
     });
 </script>
+
+<script>
+	const data2 = <?= json_encode($data['date_price_data']); ?>;
+	let cnt_ltr = 0;
+    let last_ltr = 0;
+    let last_km = 0;
+	let first_km = 0;
+
+	for (let i = 0; i < data2['liters'].length; i++) {
+		if(i === 0) {
+			first_km = data2['mileage'][i]
+			continue; // skip bcs were expecting that this was first full tank refuel so this is base value
+		}
+		cnt_ltr += data2['liters'][i]
+        last_ltr = data2['liters'][i]
+        last_km = data2['mileage'][i]
+	}
+
+    // cnt_ltr -= last_ltr // this would be used if we would track consumption from 0km
+	last_km -= first_km
+
+    document.querySelector("#avg-fl-cnsmp").textContent =
+		(cnt_ltr/last_km*100).toFixed(1) + " l/100km";
+</script>
+
 <script defer src="/js/offline-records.js"></script>

app/views/refuel/create.php

@@ -52,6 +52,12 @@
             <small class="error"><?= $this->get('validationErrors')['total_price'] ?></small>
         <?php endif; ?>
 
+        <label for="mileage">Mileage</label>
+        <input type="number" name="mileage" id="mileage" min="0" step="1" value="<?= htmlspecialchars($_POST['mileage'] ?? '0') ?>">
+        <?php if (isset($this->get('validationErrors')['mileage'])): ?>
+            <small class="error"><?= $this->get('validationErrors')['mileage'] ?></small>
+        <?php endif; ?>
+
         <label for="note">Note</label>
         <input type="text" name="note" id="note" value="<?= htmlspecialchars($_POST['note'] ?? '') ?>">
         <?php if (isset($this->get('validationErrors')['note'])): ?>

app/views/vehicles/index.php

@@ -4,7 +4,7 @@
         <p>No vehicles yet. <a href="/vehicles/create">Add your first vehicle</a>.</p>
     <?php else: ?>
         <div class="btn-wrapper">
-            <a href="/vehicles/create" class="btn-green">Add new vehicle!</a>
+            <a href="/vehicles/create" class="btn-green">Add new vehicle</a>
         </div>
         <div class="vehicle-wrapper">
         <?php foreach ($this->get('vehicles') as $vehicle): ?>
@@ -13,9 +13,21 @@
                 <p><?= htmlspecialchars($vehicle['registration_plate']) ?></p>
                 <p><?= htmlspecialchars($vehicle['fuel_type']) ?></p>
                 <p><?= htmlspecialchars($vehicle['note'] ?? "") ?></p>
-                <div class="actions">
-                    <a href="/vehicles/edit?id=<?= $vehicle['id'] ?>">Edit</a>
-                    <a href="/vehicles/delete?id=<?= $vehicle['id'] ?>" onclick="return confirm('Are you sure you want to delete this habit?')">Delete</a>
+
+                <div class="vehicle-actions">
+                    <br>
+                    <form method="POST" action="/vehicles/delete">
+                        <input type="number" name="vehicle_id" value="<?= $vehicle['id'] ?>" style="display: none">
+                        <input type="submit" value="Delete vehicle" class="btn-danger">
+                    </form>
+
+                    <?php if(!$vehicle['is_default']): ?>
+                    <br>
+                    <form method="POST" action="/vehicles/default">
+                        <input type="number" name="vehicle_id" value="<?= $vehicle['id'] ?>" style="display: none">
+                        <input type="submit" value="Set as default" class="btn-primary">
+                    </form>
+                    <?php endif; ?>
                 </div>
             </div>
         <?php endforeach; ?>

core/Database.php

@@ -63,7 +63,6 @@ class Database {
             username VARCHAR(50) NOT NULL,
             email VARCHAR(100) NOT NULL UNIQUE,
             password VARCHAR(255) NOT NULL,
-            points INT DEFAULT 0,
             created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
         ) ENGINE=InnoDB;";
 
@@ -99,6 +98,7 @@ class Database {
                 liters DOUBLE(10, 2) NOT NULL,
                 price_per_liter DOUBLE(10, 2) NOT NULL,
                 total_price DOUBLE(10, 2) NOT NULL,
+                mileage INT UNSIGNED NULL,
                 created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
                 FOREIGN KEY (vehicle_id) REFERENCES vehicles(id) ON DELETE CASCADE,
                 FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE

core/View.php

@@ -7,6 +7,11 @@ class View
         // Store the data 
         $this->data = $data;
 
+        // check for status code in data
+        if(isset($this->data['status'])){
+            http_response_code($this->data['status']);
+        }
+
         // Capture the view content
         ob_start();
         require_once views . $view . '.php';

docker-compose.yaml

@@ -6,6 +6,10 @@ services:
       MARIADB_ROOT_PASSWORD: root
     ports:
       - 3306:3306
+    volumes:
+      - fuelstats_mariadb_data:/var/lib/mysql
+    networks:
+      - fuelstats-network
     profiles: ["prod", "dev"]
 
   phpmyadmin:
@@ -15,6 +19,11 @@ services:
       - 8080:80
     environment:
       - PMA_ARBITRARY=1
+      - PMA_HOST=mariadb
+    depends_on:
+      - mariadb
+    networks:
+      - fuelstats-network
     profiles: ["dev"]
 
   fuelstats:
@@ -28,4 +37,13 @@ services:
     depends_on:
       - mariadb
     restart: on-failure:2
+    networks:
+      - fuelstats-network
     profiles: ["prod"]
+
+networks:
+  fuelstats-network:
+    driver: bridge
+
+volumes:
+  fuelstats_mariadb_data:

public/css/dashboard.css

@@ -9,7 +9,6 @@
   flex-wrap: wrap;
   gap: 1rem;
   justify-content: center;
-  margin-top: 2rem;
 }
 
 .card {

public/css/global.css

@@ -52,3 +52,8 @@ h1 {
 	background-color: var(--clr-warning-muted);
 	border: var(--borderWidth-thin) solid var(--clr-border-danger);
 }
+
+#actions {
+	padding-top: 1rem;
+	padding-bottom: 2rem;
+}

public/css/vehicles.css

@@ -27,3 +27,10 @@
 	align-items: center;
 	margin-bottom: 1rem;
 }
+
+.vehicle-actions {
+	display: flex;
+	flex-direction: row;
+	gap: .5rem;
+	margin-top: 1rem;
+}

public/index.php

@@ -46,7 +46,8 @@ $router->group('/vehicles', ['RequireAuth'], function ($router) {
     $router->add('', 'VehicleController@index');
     $router->add('/create', 'VehicleController@create');
     $router->add('/edit/{id}', 'VehicleController@edit');
-    $router->add('/delete/{id}', 'VehicleController@delete');
+    $router->add('/delete', 'VehicleController@delete');
+    $router->add('/default', 'VehicleController@setDefault');
 });
 
 $router->group('/refuel', ['RequireAuth'], function ($router) {

public/js/offline-records.js

@@ -45,11 +45,15 @@ setInterval(async () => {
 				showDashboard();
 			});
 		}
+	}
 
-		if (localStorage.getItem("refuelOfflineData")) {
-			btnOffline.textContent = "Sync data";
-			btnOffline.setAttribute("disabled", "disabled");
-		}
+	if (localStorage.getItem("refuelOfflineData")) {
+		Array.from(divActions.children).forEach(
+			(el) => (el.style.display = "none"),
+		);
+		btnOffline.style.display = "block";
+		btnOffline.textContent = "Sync data";
+		btnOffline.setAttribute("disabled", "disabled");
 	}
 
 	if (isOnline && !visible) {
@@ -107,7 +111,18 @@ btnOffline.addEventListener("click", async (e) => {
 			});
 
 			if (!res.ok) {
-				throw new Error(`Server error: ${res.statusText}`);
+				if (res.status == 400) {
+					const html = await res.text();
+
+					document.open();
+					document.write(html);
+					document.close();
+
+					localStorage.removeItem("refuelOfflineData");
+					return;
+				} else {
+					throw new Error(`Server error: ${res.statusText}`);
+				}
 			}
 
 			localStorage.removeItem("refuelOfflineData");
@@ -150,11 +165,6 @@ btnOffline.addEventListener("click", async (e) => {
     </div>
     <section class="form">
         <h1 class="header-form">Create offline record</h1>
-        <!-- <?php if ($this->get('error')): ?> -->
-        <!--     <div class="error" style="color: red; margin-bottom: 1rem;"> -->
-        <!--         <?= htmlspecialchars($this->get('error')) ?> -->
-        <!--     </div> -->
-        <!-- <?php endif; ?> -->
         <form id="offline_refuel_add">
             <label for="vehicle">Vehicle</label>
             <select name="vehicle" id="vehicle">
@@ -164,13 +174,7 @@ btnOffline.addEventListener("click", async (e) => {
 									`<option value="${el.id}">${el.name} | ${el.registration_plate}</option>`,
 							)
 							.join("")}
-            <!-- <?php foreach ($this->get('vehicles') as $vehicle): ?> -->
-            <!--     <option value="<?= $vehicle['id'] ?>"><?= $vehicle['name'] . " | " . $vehicle['registration_plate'] ?></option> -->
-            <!-- <?php endforeach; ?> -->
             </select>
-            <!-- <?php if (isset($this->get('validationErrors')['vehicle'])): ?> -->
-            <!--     <small class="error"><?= $this->get('validationErrors')['vehicle'] ?></small> -->
-            <!-- <?php endif; ?> -->
 
             <label for="fuel_type">Fuel type</label>
             <select name="fuel_type" id="fuel_type">
@@ -182,39 +186,67 @@ btnOffline.addEventListener("click", async (e) => {
                 <option value="Premium Gasoline 98">Premium Gasoline 98</option>
                 <option value="Other">Other</option>
             </select>
-            <!-- <?php if (isset($this->get('validationErrors')['fuel_type'])): ?> -->
-            <!--     <small class="error"><?= $this->get('validationErrors')['fuel_type'] ?></small> -->
-            <!-- <?php endif; ?> -->
 
             <label for="liters">Liters</label>
             <input type="number" name="liters" id="liters" min="0" step=".01" value="0.0">
-            <!-- <?php if (isset($this->get('validationErrors')['liters'])): ?> -->
-            <!--     <small class="error"><?= $this->get('validationErrors')['liters'] ?></small> -->
-            <!-- <?php endif; ?> -->
+            <!-- <small class="error"><?= $this->get('validationErrors')['liters'] ?></small> -->
 
             <label for="price_per_liter">Price per liter</label>
             <input type="number" name="price_per_liter" id="price_per_liter" min="0" step=".01" value="0.0">
-            <!-- <?php if (isset($this->get('validationErrors')['price_per_liter'])): ?> -->
-            <!--     <small class="error"><?= $this->get('validationErrors')['price_per_liter'] ?></small> -->
-            <!-- <?php endif; ?> -->
+            <!-- <small class="error"><?= $this->get('validationErrors')['price_per_liter'] ?></small> -->
 
             <label for="total_price">Total price</label>
             <input type="number" name="total_price" id="total_price" min="0" step=".01" value="0.0">
-            <!-- <?php if (isset($this->get('validationErrors')['total_price'])): ?> -->
-            <!--     <small class="error"><?= $this->get('validationErrors')['total_price'] ?></small> -->
-            <!-- <?php endif; ?> -->
+            <!-- <small class="error"><?= $this->get('validationErrors')['total_price'] ?></small> -->
+
+        		<label for="mileage">Mileage</label>
+        		<input type="number" name="mileage" id="mileage" min="0" step="1" value="0">
+         		<!-- <small class="error"><?= $this->get('validationErrors')['mileage'] ?></small> -->
 
             <label for="note">Note</label>
             <input type="text" name="note" id="note">
-            <!-- <?php if (isset($this->get('validationErrors')['note'])): ?> -->
-            <!--     <small class="error"><?= $this->get('validationErrors')['note'] ?></small> -->
-            <!-- <?php endif; ?> -->
+            <!-- <small class="error"><?= $this->get('validationErrors')['note'] ?></small> -->
 
             <input type="submit" id="btn-offline-submit" value="Create fuel record">
         </form>
     </section>
   `;
 	document.querySelector("main").appendChild(offline);
+
+	const inp_lit = document.querySelector("input#liters");
+	const inp_ppl = document.querySelector("input#price_per_liter");
+	const inp_tot = document.querySelector("input#total_price");
+
+	const rnd = (num) => Math.round((num + Number.EPSILON) * 100) / 100;
+
+	function calculate() {
+		let liters = Number(inp_lit.value);
+		let price_per_liter = Number(inp_ppl.value);
+		let total_price = Number(inp_tot.value);
+
+		if (price_per_liter > 0 && liters > 0) {
+			total_price = rnd(liters * price_per_liter);
+		}
+
+		if (price_per_liter > 0 && total_price > 0) {
+			liters = rnd(total_price / price_per_liter);
+		}
+
+		if (liters > 0 && total_price > 0) {
+			price_per_liter = rnd(total_price / liters);
+		}
+
+		inp_lit.value = liters;
+		inp_ppl.value = price_per_liter;
+		inp_tot.value = total_price;
+	}
+
+	[inp_lit, inp_ppl, inp_tot].forEach((inp) => {
+		inp.addEventListener("change", () => {
+			calculate();
+		});
+	});
+
 	const btnSubmit = document.querySelector("#btn-offline-submit");
 	btnSubmit.addEventListener("click", (e) => {
 		e.preventDefault();
@@ -229,6 +261,7 @@ btnOffline.addEventListener("click", async (e) => {
 			total_price: document.querySelector(
 				"form#offline_refuel_add #total_price",
 			).value,
+			mileage: document.querySelector("form#offline_refuel_add #mileage").value,
 			note: document.querySelector("form#offline_refuel_add #note").value,
 		};