first commit

README.md

@@ -1,10 +1,50 @@
-Kalkulator BMI
+# Kalkulator BMI
-===============
 
-Silahkan kembangkan aplikasi ini untuk melakukan perhitungan BMI
+Aplikasi Android sederhana untuk menghitung Indeks Massa Tubuh (IMT) atau *Body Mass Index* (BMI). Aplikasi ini dibuat sebagai bagian dari tugas atau latihan pengembangan aplikasi Android.
 
-Petunjuk lebih detil dapat dibaca di
+## Deskripsi
-https://docs.google.com/document/d/1iGiC0Bg3Bdcd2Maq45TYkCDUkZ5Ql51E/edit?rtpof=true
 
-Starter dimodifikasi dan terinspirasi dari:
+*Body Mass Index* (BMI) atau Indeks Massa Tubuh (IMT) adalah angka yang menjadi standar penilaian untuk menentukan apakah berat badan Anda tergolong normal, kurang, berlebih, atau obesitas. [21] Perhitungan ini didasarkan pada perbandingan antara berat dan tinggi badan. [21] Aplikasi ini menyediakan antarmuka yang mudah digunakan untuk memasukkan data dan melihat hasilnya secara langsung.
-https://developer.android.com/codelabs/basic-android-compose-calculate-tip#0
+
+Aplikasi ini bertujuan untuk:
+*   Menyediakan alat praktis bagi pengguna untuk memantau berat badan.
+*   Membantu pengguna memahami kategori berat badan mereka (kurang, normal, berlebih).
+*   Menjadi proyek latihan untuk pengembangan aplikasi Android menggunakan teknologi modern.
+
+## Fitur
+
+*   **Input Data Pengguna:** Memasukkan berat badan (kg) dan tinggi badan (cm).
+*   **Perhitungan BMI:** Menghitung skor BMI secara otomatis berdasarkan data yang dimasukkan.
+*   **Tampilan Hasil:** Menampilkan skor BMI beserta kategori berat badan (contoh: Kurus, Normal, Gemuk).
+*   **Antarmuka Intuitif:** Desain yang simpel dan mudah digunakan.
+
+## Teknologi
+
+Proyek ini dibangun menggunakan:
+*   **Kotlin:** Bahasa pemrograman yang direkomendasikan Google untuk pengembangan Android. [8]
+*   **Jetpack Compose:** *Toolkit* modern dari Google untuk membangun UI Android secara deklaratif, yang memungkinkan pembuatan antarmuka pengguna dengan kode yang lebih ringkas dan efisien. [2, 6, 8]
+*   **Android Studio:** Lingkungan pengembangan terintegrasi (IDE) resmi untuk pengembangan aplikasi Android. [6]
+*   **Material Design 3:** Implementasi sistem desain Google untuk memberikan tampilan dan nuansa yang konsisten pada aplikasi. [6]
+
+## Petunjuk Pengembangan
+
+Petunjuk lebih detail mengenai pengembangan dan fitur yang harus diimplementasikan dapat dibaca di dokumen berikut:
+[Petunjuk Pengerjaan Proyek](https://docs.google.com/document/d/1iGiC0Bg3Bdcd2Maq45TYkCDUkZ5Ql51E/edit?rtpof=true)
+
+## Cara Berkontribusi
+
+Kontribusi dari Anda sangat diharapkan! Jika Anda ingin berkontribusi pada proyek ini, silakan ikuti langkah-langkah berikut:
+1.  **Fork** repositori ini ke akun GitHub Anda. [1]
+2.  **Clone** repositori yang sudah di-fork ke mesin lokal Anda. [1]
+3.  Buat **branch** baru untuk setiap fitur atau perbaikan yang akan Anda kerjakan (`git checkout -b nama-fitur-anda`). [4]
+4.  Lakukan perubahan pada kode.
+5.  **Commit** perubahan Anda dengan pesan yang jelas dan deskriptif (`git commit -m 'Menambahkan fitur X'`). [4]
+6.  **Push** perubahan ke branch Anda di repositori fork (`git push origin nama-fitur-anda`). [4]
+7.  Buat **Pull Request** dari branch Anda ke branch `main` repositori ini. [3]
+
+Pastikan untuk membaca aturan kontribusi (jika ada) sebelum memulai. [1]
+
+## Inspirasi
+
+Proyek starter ini dimodifikasi dan terinspirasi dari codelab resmi Android:
+[Basic Android Compose - Calculate Tip](https://developer.android.com/codelabs/basic-android-compose-calculate-tip#0)

app/src/main/java/com/example/tiptime/MainActivity.kt

@@ -1,18 +1,15 @@
 /*
- * Copyright (C) 2023 The Android Open Source Project
+ * 🌃 Cyberpunk BMI Calculator App
- *
+ * Developed with ❤ by INDRIS ALPASELA
- * Licensed under the Apache License, Version 2.0 (the "License");
+ * NPM: [202310715200]
- * you may not use this file except in compliance with the License.
+ * Nama: INDRIS ALPASELA
- * You may obtain a copy of the License at
  *
+ * Licensed under the Apache License, Version 2.0
  * https://www.apache.org/licenses/LICENSE-2.0
  *
- * Unless required by applicable law or agreed to in writing, software
+ * ⚡ Modern BMI calculator with futuristic Cyberpunk Neon theme!
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
  */
+
 package com.example.tiptime
 
 import android.os.Bundle
@@ -20,195 +17,724 @@ import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
 import androidx.annotation.DrawableRes
-import androidx.annotation.StringRes
+import androidx.compose.animation.Crossfade
-import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.animation.core.*
-import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.Canvas
-import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.background
-import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.*
-import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.foundation.layout.fillMaxWidth
-import androidx.compose.foundation.layout.height
-import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.layout.safeDrawingPadding
-import androidx.compose.foundation.layout.statusBarsPadding
-import androidx.compose.foundation.layout.wrapContentWidth
 import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.text.KeyboardOptions
 import androidx.compose.foundation.verticalScroll
-import androidx.compose.material3.Icon
+import androidx.compose.material.icons.Icons
-import androidx.compose.material3.MaterialTheme
+import androidx.compose.material.icons.filled.ArrowBack
-import androidx.compose.material3.Surface
+import androidx.compose.material3.*
-import androidx.compose.material3.Switch
+import androidx.compose.runtime.*
-import androidx.compose.material3.Text
-import androidx.compose.material3.TextField
-import androidx.compose.runtime.Composable
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.remember
-import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.graphics.*
 import androidx.compose.ui.res.painterResource
-import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.input.ImeAction
 import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
 import com.example.tiptime.ui.theme.TipTimeTheme
-import java.text.NumberFormat
+import kotlin.math.pow
+import kotlin.math.sin
 
+// ---------------- CYBERPUNK NEON COLORS ----------------
+val NeonPink = Color(0xFFFF006E)
+val NeonCyan = Color(0xFF00F5FF)
+val NeonPurple = Color(0xFF8B00FF)
+val NeonYellow = Color(0xFFFFFB00)
+val CyberBlack = Color(0xFF0A0E27)
+val CyberDarkBlue = Color(0xFF1A1F3A)
+val NeonGreen = Color(0xFF39FF14)
+val NeonOrange = Color(0xFFFF3C00)
+
+// ---------------- MAIN ACTIVITY ----------------
 class MainActivity : ComponentActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         enableEdgeToEdge()
         super.onCreate(savedInstanceState)
         setContent {
             TipTimeTheme {
-                Surface(
+                Surface(modifier = Modifier.fillMaxSize()) {
-                    modifier = Modifier.fillMaxSize(),
+                    BMIApp()
-                ) {
-                    TipTimeLayout()
                 }
             }
         }
     }
 }
 
+// ---------------- APP NAVIGATION ----------------
 @Composable
-fun TipTimeLayout() {
+fun BMIApp() {
-    var amountInput by remember { mutableStateOf("") }
+    var currentScreen by remember { mutableStateOf("home") }
-    var tipInput by remember { mutableStateOf("") }
-    var roundUp by remember { mutableStateOf(false) }
 
-    val BmiHeight = amountInput.toDoubleOrNull() ?: 0.0
+    Crossfade(targetState = currentScreen, label = "screen_transition") { screen ->
-    val BmiWeight = tipInput.toDoubleOrNull() ?: 0.0
+        when (screen) {
-    val bmi = calculateBMI(BmiHeight, BmiWeight, roundUp)
+            "home" -> HomeScreen(onNavigateToCalculator = { currentScreen = "calculator" })
-    val category = calculateBMICategory(BmiHeight, BmiWeight, roundUp)
+            "calculator" -> BMICalculatorScreen(onNavigateBack = { currentScreen = "home" })
+        }
+    }
+}
+
+// ---------------- HOME SCREEN WITH ANIMATED NEON EFFECT ----------------
+@Composable
+fun HomeScreen(onNavigateToCalculator: () -> Unit) {
+    // Animasi untuk efek neon berkedip
+    val infiniteTransition = rememberInfiniteTransition(label = "neon_pulse")
+    val glowAlpha by infiniteTransition.animateFloat(
+        initialValue = 0.3f,
+        targetValue = 0.8f,
+        animationSpec = infiniteRepeatable(
+            animation = tween(1500, easing = FastOutSlowInEasing),
+            repeatMode = RepeatMode.Reverse
+        ),
+        label = "glow_animation"
+    )
+
+    Box(
+        modifier = Modifier
+            .fillMaxSize()
+            .background(
+                brush = Brush.verticalGradient(
+                    colors = listOf(CyberBlack, CyberDarkBlue, Color(0xFF0D1B2A))
+                )
+            )
+    ) {
+        // Grid lines untuk efek cyberpunk
+        Canvas(modifier = Modifier.fillMaxSize()) {
+            val gridSize = 60f
+            // Vertical lines
+            var x = 0f
+            while (x < size.width) {
+                drawLine(
+                    color = NeonCyan.copy(alpha = 0.1f),
+                    start = Offset(x, 0f),
+                    end = Offset(x, size.height),
+                    strokeWidth = 1f
+                )
+                x += gridSize
+            }
+            // Horizontal lines
+            var y = 0f
+            while (y < size.height) {
+                drawLine(
+                    color = NeonPink.copy(alpha = 0.1f),
+                    start = Offset(0f, y),
+                    end = Offset(size.width, y),
+                    strokeWidth = 1f
+                )
+                y += gridSize
+            }
+
+            // Neon circles dengan efek glow
+            drawCircle(
+                color = NeonPink.copy(alpha = glowAlpha * 0.2f),
+                radius = 200f,
+                center = Offset(x = size.width * 0.2f, y = size.height * 0.3f)
+            )
+            drawCircle(
+                color = NeonCyan.copy(alpha = glowAlpha * 0.15f),
+                radius = 250f,
+                center = Offset(x = size.width * 0.8f, y = size.height * 0.6f)
+            )
+            drawCircle(
+                color = NeonPurple.copy(alpha = glowAlpha * 0.18f),
+                radius = 180f,
+                center = Offset(x = size.width * 0.5f, y = size.height * 0.8f)
+            )
+        }
 
         Column(
             modifier = Modifier
+                .fillMaxSize()
                 .statusBarsPadding()
-            .padding(horizontal = 40.dp)
+                .padding(32.dp)
-            .verticalScroll(rememberScrollState())
                 .safeDrawingPadding(),
             horizontalAlignment = Alignment.CenterHorizontally,
             verticalArrangement = Arrangement.Center
         ) {
-        Text(
+            // Logo/Icon section dengan border neon
-            text = stringResource(R.string.calculate_tip),
+            Box(
                 modifier = Modifier
-                .padding(bottom = 16.dp, top = 40.dp)
+                    .size(80.dp)
-                .align(alignment = Alignment.Start)
+                    .background(
+                        brush = Brush.linearGradient(
+                            colors = listOf(NeonPink, NeonCyan)
+                        ),
+                        shape = RoundedCornerShape(16.dp)
                     )
-        EditNumberField(
+                    .padding(2.dp)
-            label = R.string.height,
+                    .background(CyberBlack, RoundedCornerShape(14.dp)),
+                contentAlignment = Alignment.Center
+            ) {
+                Text(
+                    text = "⚡",
+                    fontSize = 40.sp,
+                    color = NeonCyan
+                )
+            }
+
+            Spacer(Modifier.height(24.dp))
+
+            Text(
+                text = "CYBER BMI",
+                style = MaterialTheme.typography.displayLarge.copy(
+                    fontWeight = FontWeight.Black,
+                    brush = Brush.linearGradient(
+                        colors = listOf(NeonPink, NeonCyan, NeonPurple)
+                    )
+                ),
+                textAlign = TextAlign.Center
+            )
+
+            Text(
+                text = "// CALCULATOR_V2.0",
+                style = MaterialTheme.typography.titleMedium.copy(
+                    fontWeight = FontWeight.Light,
+                    letterSpacing = 4.sp
+                ),
+                color = NeonCyan.copy(alpha = 0.7f),
+                textAlign = TextAlign.Center,
+                modifier = Modifier.padding(top = 8.dp)
+            )
+
+            Text(
+                text = "< Developed by Faris Naufal />",
+                style = MaterialTheme.typography.bodySmall.copy(
+                    fontWeight = FontWeight.Light
+                ),
+                color = Color.White.copy(alpha = 0.5f),
+                textAlign = TextAlign.Center,
+                modifier = Modifier.padding(top = 4.dp)
+            )
+
+            Spacer(Modifier.height(16.dp))
+
+            // Deskripsi dengan border cyberpunk
+            Card(
+                colors = CardDefaults.cardColors(
+                    containerColor = CyberDarkBlue.copy(alpha = 0.6f)
+                ),
+                shape = RoundedCornerShape(12.dp),
+                modifier = Modifier.padding(horizontal = 16.dp)
+            ) {
+                Text(
+                    text = "Hitung Body Mass Index Anda dengan teknologi futuristik",
+                    style = MaterialTheme.typography.bodyLarge,
+                    textAlign = TextAlign.Center,
+                    color = Color.White.copy(alpha = 0.9f),
+                    modifier = Modifier.padding(16.dp)
+                )
+            }
+
+            Spacer(Modifier.height(48.dp))
+
+            // Button dengan efek neon gradient
+            Button(
+                onClick = onNavigateToCalculator,
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .height(56.dp),
+                colors = ButtonDefaults.buttonColors(
+                    containerColor = Color.Transparent
+                ),
+                contentPadding = PaddingValues(0.dp),
+                shape = RoundedCornerShape(12.dp)
+            ) {
+                Box(
+                    modifier = Modifier
+                        .fillMaxSize()
+                        .background(
+                            brush = Brush.horizontalGradient(
+                                colors = listOf(NeonPink, NeonPurple, NeonCyan)
+                            )
+                        ),
+                    contentAlignment = Alignment.Center
+                ) {
+                    Text(
+                        "⚡ MULAI SCANNING",
+                        style = MaterialTheme.typography.titleMedium.copy(
+                            fontWeight = FontWeight.Bold,
+                            letterSpacing = 2.sp
+                        ),
+                        color = Color.White
+                    )
+                }
+            }
+        }
+    }
+}
+
+// ---------------- BMI CALCULATOR SCREEN ----------------
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun BMICalculatorScreen(onNavigateBack: () -> Unit) {
+    var heightInput by remember { mutableStateOf("") }
+    var weightInput by remember { mutableStateOf("") }
+    var useUSUnits by remember { mutableStateOf(false) }
+
+    // Validasi input untuk mencegah nilai yang tidak wajar
+    val height = heightInput.toDoubleOrNull() ?: 0.0
+    val weight = weightInput.toDoubleOrNull() ?: 0.0
+
+    // Validasi range yang wajar
+    val isValidHeight = if (useUSUnits) height in 20.0..96.0 else height in 50.0..250.0
+    val isValidWeight = if (useUSUnits) weight in 20.0..1000.0 else weight in 10.0..500.0
+
+    val bmi = calculateBMI(height, weight, useUSUnits)
+    val category = calculateBMICategory(height, weight, useUSUnits)
+
+    Scaffold(
+        topBar = {
+            TopAppBar(
+                title = {
+                    Text(
+                        "⚡ CYBER BMI SCANNER",
+                        style = MaterialTheme.typography.titleLarge.copy(
+                            fontWeight = FontWeight.Bold,
+                            letterSpacing = 1.sp
+                        )
+                    )
+                },
+                navigationIcon = {
+                    IconButton(onClick = onNavigateBack) {
+                        Icon(
+                            Icons.Default.ArrowBack,
+                            contentDescription = "Kembali",
+                            tint = NeonCyan
+                        )
+                    }
+                },
+                colors = TopAppBarDefaults.topAppBarColors(
+                    containerColor = CyberBlack,
+                    titleContentColor = NeonPink
+                )
+            )
+        }
+    ) { innerPadding ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .background(
+                    brush = Brush.verticalGradient(
+                        colors = listOf(CyberBlack, CyberDarkBlue)
+                    )
+                )
+                .padding(innerPadding)
+                .padding(horizontal = 24.dp)
+                .verticalScroll(rememberScrollState())
+                .safeDrawingPadding(),
+            horizontalAlignment = Alignment.CenterHorizontally
+        ) {
+
+            Spacer(modifier = Modifier.height(16.dp))
+
+            // Unit Switch dengan desain cyberpunk
+            UnitSwitchRow(
+                useUSUnits = useUSUnits,
+                onUnitChanged = { useUSUnits = it },
+                modifier = Modifier.padding(bottom = 24.dp)
+            )
+
+            // Input fields dengan neon border
+            CyberTextField(
+                label = if (useUSUnits) "HEIGHT (inches) ⚡" else "TINGGI (cm) ⚡",
                 leadingIcon = R.drawable.number,
-            keyboardOptions = KeyboardOptions.Default.copy(
+                keyboardOptions = KeyboardOptions(
                     keyboardType = KeyboardType.Number,
                     imeAction = ImeAction.Next
                 ),
-            value = amountInput,
+                value = heightInput,
-            onValueChanged = { amountInput = it },
+                onValueChanged = { heightInput = it },
-            modifier = Modifier.padding(bottom = 32.dp).fillMaxWidth(),
+                isError = height > 0 && !isValidHeight,
+                errorMessage = if (useUSUnits) "Range: 20-96 inches" else "Range: 50-250 cm",
+                modifier = Modifier.fillMaxWidth().padding(bottom = 20.dp)
             )
-        EditNumberField(
+
-            label = R.string.weight,
+            CyberTextField(
+                label = if (useUSUnits) "WEIGHT (lbs) ⚡" else "BERAT (kg) ⚡",
                 leadingIcon = R.drawable.number,
-            keyboardOptions = KeyboardOptions.Default.copy(
+                keyboardOptions = KeyboardOptions(
                     keyboardType = KeyboardType.Number,
                     imeAction = ImeAction.Done
                 ),
-            value = tipInput,
+                value = weightInput,
-            onValueChanged = { tipInput = it },
+                onValueChanged = { weightInput = it },
-            modifier = Modifier.padding(bottom = 32.dp).fillMaxWidth(),
+                isError = weight > 0 && !isValidWeight,
-        )
+                errorMessage = if (useUSUnits) "Range: 20-1000 lbs" else "Range: 10-500 kg",
-        RoundTheTipRow(
+                modifier = Modifier.fillMaxWidth().padding(bottom = 32.dp)
-            roundUp = roundUp,
-            onRoundUpChanged = { roundUp = it },
-            modifier = Modifier.padding(bottom = 32.dp)
-        )
-        Text(
-            text = stringResource(R.string.bmi_calculation, bmi),
-            style = MaterialTheme.typography.displaySmall
-        )
-        Text(
-            text = stringResource(R.string.bmi_category, category),
-            style = MaterialTheme.typography.displaySmall
             )
 
-        Spacer(modifier = Modifier.height(150.dp))
+            // Tampilkan hasil hanya jika input valid
+            if (height > 0 && weight > 0) {
+                if (isValidHeight && isValidWeight) {
+                    // Card hasil BMI dengan efek neon
+                    Card(
+                        colors = CardDefaults.cardColors(
+                            containerColor = CyberDarkBlue.copy(alpha = 0.8f)
+                        ),
+                        shape = RoundedCornerShape(20.dp),
+                        modifier = Modifier
+                            .fillMaxWidth()
+                            .background(
+                                brush = Brush.linearGradient(
+                                    colors = listOf(
+                                        NeonPink.copy(alpha = 0.3f),
+                                        NeonCyan.copy(alpha = 0.3f)
+                                    )
+                                ),
+                                shape = RoundedCornerShape(20.dp)
+                            )
+                    ) {
+                        Column(
+                            modifier = Modifier.padding(24.dp),
+                            horizontalAlignment = Alignment.CenterHorizontally
+                        ) {
+                            Text(
+                                text = "// SCAN RESULT",
+                                style = MaterialTheme.typography.titleSmall.copy(
+                                    letterSpacing = 3.sp
+                                ),
+                                color = NeonCyan.copy(alpha = 0.7f)
+                            )
+                            Spacer(modifier = Modifier.height(8.dp))
+                            Text(
+                                text = bmi,
+                                style = MaterialTheme.typography.displayLarge.copy(
+                                    fontWeight = FontWeight.Black,
+                                    brush = Brush.linearGradient(
+                                        colors = listOf(
+                                            getBMICategoryColor(category),
+                                            getBMICategoryColor(category).copy(alpha = 0.7f)
+                                        )
+                                    )
+                                )
+                            )
+                            Spacer(modifier = Modifier.height(4.dp))
+                            Text(
+                                text = category.uppercase(),
+                                style = MaterialTheme.typography.titleMedium.copy(
+                                    fontWeight = FontWeight.Bold,
+                                    letterSpacing = 2.sp
+                                ),
+                                color = getBMICategoryColor(category)
+                            )
+                        }
+                    }
+
+                    Spacer(modifier = Modifier.height(24.dp))
+
+                    BMICategoryTable()
+                } else {
+                    // Peringatan untuk input tidak valid
+                    Card(
+                        colors = CardDefaults.cardColors(
+                            containerColor = NeonOrange.copy(alpha = 0.2f)
+                        ),
+                        shape = RoundedCornerShape(12.dp),
+                        modifier = Modifier.fillMaxWidth()
+                    ) {
+                        Text(
+                            text = "⚠ INPUT TIDAK VALID\nMasukkan nilai yang wajar",
+                            style = MaterialTheme.typography.bodyLarge.copy(
+                                fontWeight = FontWeight.SemiBold
+                            ),
+                            color = NeonOrange,
+                            textAlign = TextAlign.Center,
+                            modifier = Modifier.padding(16.dp)
+                        )
+                    }
+                }
+            }
+
+            Spacer(modifier = Modifier.height(24.dp))
+        }
+    }
+}
+
+// ---------------- BMI CATEGORY TABLE WITH CYBERPUNK STYLE ----------------
+@Composable
+fun BMICategoryTable() {
+    Card(
+        colors = CardDefaults.cardColors(
+            containerColor = CyberDarkBlue.copy(alpha = 0.7f)
+        ),
+        shape = RoundedCornerShape(16.dp),
+        modifier = Modifier.fillMaxWidth()
+    ) {
+        Column(
+            modifier = Modifier.padding(20.dp),
+            horizontalAlignment = Alignment.CenterHorizontally
+        ) {
+            Text(
+                text = "// BMI CATEGORIES",
+                style = MaterialTheme.typography.titleMedium.copy(
+                    fontWeight = FontWeight.Bold,
+                    letterSpacing = 2.sp
+                ),
+                color = NeonCyan,
+                modifier = Modifier.padding(bottom = 12.dp)
+            )
+
+            Divider(
+                color = NeonPink.copy(alpha = 0.5f),
+                thickness = 2.dp,
+                modifier = Modifier.padding(bottom = 12.dp)
+            )
+
+            BMICategoryRow("UNDERWEIGHT", "< 18.5", Color(0xFF00D9FF))
+            Spacer(modifier = Modifier.height(8.dp))
+            BMICategoryRow("NORMAL", "18.5 – 24.9", NeonGreen)
+            Spacer(modifier = Modifier.height(8.dp))
+            BMICategoryRow("OVERWEIGHT", "25 – 29.9", NeonYellow)
+            Spacer(modifier = Modifier.height(8.dp))
+            BMICategoryRow("OBESE", "≥ 30", NeonOrange)
+        }
     }
 }
 
 @Composable
-fun EditNumberField(
+fun BMICategoryRow(label: String, range: String, color: Color) {
-    @StringRes label: Int,
+    Row(
+        modifier = Modifier
+            .fillMaxWidth()
+            .background(
+                brush = Brush.horizontalGradient(
+                    colors = listOf(
+                        color.copy(alpha = 0.3f),
+                        color.copy(alpha = 0.1f)
+                    )
+                ),
+                shape = RoundedCornerShape(8.dp)
+            )
+            .padding(12.dp),
+        horizontalArrangement = Arrangement.SpaceBetween,
+        verticalAlignment = Alignment.CenterVertically
+    ) {
+        Text(
+            text = label,
+            color = color,
+            fontSize = 14.sp,
+            fontWeight = FontWeight.Bold,
+            letterSpacing = 1.sp,
+            maxLines = 1,
+            overflow = TextOverflow.Ellipsis
+        )
+        Text(
+            text = range,
+            color = color,
+            fontSize = 14.sp,
+            fontWeight = FontWeight.SemiBold
+        )
+    }
+}
+
+// ---------------- CUSTOM CYBERPUNK TEXT FIELD ----------------
+@Composable
+fun CyberTextField(
+    label: String,
     @DrawableRes leadingIcon: Int,
     keyboardOptions: KeyboardOptions,
     value: String,
     onValueChanged: (String) -> Unit,
+    isError: Boolean = false,
+    errorMessage: String = "",
     modifier: Modifier = Modifier
 ) {
+    Column(modifier = modifier) {
         TextField(
             value = value,
-        singleLine = true,
-        leadingIcon = { Icon(painter = painterResource(id = leadingIcon), null) },
-        modifier = modifier,
             onValueChange = onValueChanged,
-        label = { Text(stringResource(label)) },
+            singleLine = true,
-        keyboardOptions = keyboardOptions
+            leadingIcon = {
+                Icon(
+                    painterResource(id = leadingIcon),
+                    contentDescription = null,
+                    tint = if (isError) NeonOrange else NeonCyan
                 )
+            },
+            label = {
+                Text(
+                    label,
+                    color = if (isError) NeonOrange else NeonPink,
+                    style = MaterialTheme.typography.bodyMedium.copy(
+                        letterSpacing = 1.sp
+                    )
+                )
+            },
+            placeholder = {
+                Text(
+                    "Enter value...",
+                    color = Color.Gray.copy(alpha = 0.5f)
+                )
+            },
+            keyboardOptions = keyboardOptions,
+            isError = isError,
+            colors = TextFieldDefaults.colors(
+                focusedContainerColor = CyberDarkBlue.copy(alpha = 0.6f),
+                unfocusedContainerColor = CyberDarkBlue.copy(alpha = 0.4f),
+                focusedTextColor = Color.White,
+                unfocusedTextColor = Color.White,
+                focusedIndicatorColor = if (isError) NeonOrange else NeonCyan,
+                unfocusedIndicatorColor = if (isError) NeonOrange.copy(alpha = 0.5f) else NeonPurple.copy(alpha = 0.5f),
+                errorIndicatorColor = NeonOrange,
+                errorContainerColor = CyberDarkBlue.copy(alpha = 0.6f),
+                cursorColor = NeonCyan
+            ),
+            shape = RoundedCornerShape(12.dp),
+            modifier = Modifier.fillMaxWidth()
+        )
+
+        if (isError && errorMessage.isNotEmpty()) {
+            Text(
+                text = errorMessage,
+                color = NeonOrange,
+                style = MaterialTheme.typography.bodySmall,
+                modifier = Modifier.padding(start = 16.dp, top = 4.dp)
+            )
+        }
+    }
 }
 
+// ---------------- UNIT SWITCH WITH CYBERPUNK STYLE ----------------
 @Composable
-fun RoundTheTipRow(
+fun UnitSwitchRow(
-    roundUp: Boolean,
+    useUSUnits: Boolean,
-    onRoundUpChanged: (Boolean) -> Unit,
+    onUnitChanged: (Boolean) -> Unit,
     modifier: Modifier = Modifier
 ) {
-    Row(
+    Card(
-        modifier = modifier.fillMaxWidth(),
+        colors = CardDefaults.cardColors(
-        verticalAlignment = Alignment.CenterVertically
+            containerColor = CyberDarkBlue.copy(alpha = 0.6f)
+        ),
+        shape = RoundedCornerShape(12.dp),
+        modifier = modifier.fillMaxWidth()
     ) {
-        Text(text = stringResource(R.string.use_usc))
+        Row(
-        Switch(
             modifier = Modifier
                 .fillMaxWidth()
-                .wrapContentWidth(Alignment.End),
+                .padding(16.dp),
-            checked = roundUp,
+            verticalAlignment = Alignment.CenterVertically,
-            onCheckedChange = onRoundUpChanged
+            horizontalArrangement = Arrangement.SpaceBetween
+        ) {
+            Column {
+                Text(
+                    text = if (useUSUnits) "US UNITS" else "METRIC UNITS",
+                    color = NeonCyan,
+                    style = MaterialTheme.typography.titleMedium.copy(
+                        fontWeight = FontWeight.Bold,
+                        letterSpacing = 1.sp
+                    )
+                )
+                Text(
+                    text = if (useUSUnits) "inches, lbs" else "cm, kg",
+                    color = Color.White.copy(alpha = 0.6f),
+                    style = MaterialTheme.typography.bodySmall
                 )
             }
+            Switch(
+                checked = useUSUnits,
+                onCheckedChange = onUnitChanged,
+                colors = SwitchDefaults.colors(
+                    checkedThumbColor = NeonCyan,
+                    checkedTrackColor = NeonPink.copy(alpha = 0.5f),
+                    uncheckedThumbColor = Color.Gray,
+                    uncheckedTrackColor = CyberBlack
+                )
+            )
+        }
+    }
+}
+
+// ---------------- LOGIC & UTILITIES ----------------
+
+/**
+ * Menentukan warna kategori BMI berdasarkan status kesehatan
+ * @param category String kategori BMI
+ * @return Color warna yang sesuai dengan kategori
+ */
+@Composable
+fun getBMICategoryColor(category: String): Color = when {
+    category.contains("Underweight", true) || category.contains("Kurus", true) -> Color(0xFF00D9FF)
+    category.contains("Normal", true) -> NeonGreen
+    category.contains("Overweight", true) || category.contains("Gemuk", true) -> NeonYellow
+    category.contains("Obese", true) || category.contains("Obesitas", true) -> NeonOrange
+    else -> Color.White
 }
 
 /**
- * Calculates the BMI
+ * Menghitung nilai BMI berdasarkan tinggi dan berat
+ * Formula Metrik: BMI = weight (kg) / (height (m))^2
+ * Formula US: BMI = (weight (lbs) / (height (inches))^2) * 703
  *
- * Catatan: tambahkan unit test untuk kalkulasi BMI ini
+ * @param height Tinggi badan (cm untuk metrik, inches untuk US)
- */
+ * @param weight Berat badan (kg untuk metrik, lbs untuk US)
-private fun calculateBMI(BmiHeight: Double, BmiWeight: Double = 15.0, roundUp: Boolean): String {
+ * @param useUSUnits Boolean untuk menentukan sistem satuan
-    var bmi = BmiWeight / 100 * BmiHeight
+ * @return String nilai BMI dengan 1 desimal
-    if (roundUp) {
-        bmi = kotlin.math.ceil(bmi)
-    }
-    return NumberFormat.getNumberInstance().format(bmi)
-}
-/**
- * Calculates the BMI Category
- *
- * Catatan: tambahkan unit test untuk kalkulasi BMI ini
  */
+private fun calculateBMI(height: Double, weight: Double, useUSUnits: Boolean): String {
+    // Validasi input tidak boleh nol atau negatif
+    if (height <= 0 || weight <= 0) return "-"
 
-private fun calculateBMICategory(BmiHeight: Double, BmiWeight: Double = 15.0, roundUp: Boolean): String {
+    val bmi = if (useUSUnits) {
-    var bmi = BmiWeight / 100 * BmiHeight
+        // Formula US: (weight / height^2) * 703
-    if (roundUp) {
+        (weight / height.pow(2)) * 703
-        bmi = kotlin.math.ceil(bmi)
+    } else {
+        // Formula Metrik: weight / (height in meters)^2
+        weight / (height / 100).pow(2)
     }
-    return NumberFormat.getNumberInstance().format(bmi)
+
+    // Format dengan 1 angka desimal
+    return String.format("%.1f", bmi)
 }
+
+/**
+ * Menentukan kategori BMI berdasarkan standar WHO
+ * - Underweight: BMI < 18.5
+ * - Normal: BMI 18.5-24.9
+ * - Overweight: BMI 25-29.9
+ * - Obese: BMI >= 30
+ *
+ * @param height Tinggi badan
+ * @param weight Berat badan
+ * @param useUSUnits Boolean sistem satuan
+ * @return String kategori BMI
+ */
+private fun calculateBMICategory(height: Double, weight: Double, useUSUnits: Boolean): String {
+    if (height <= 0 || weight <= 0) return "-"
+
+    val bmi = if (useUSUnits) {
+        (weight / height.pow(2)) * 703
+    } else {
+        weight / (height / 100).pow(2)
+    }
+
+    return when {
+        bmi < 18.5 -> "Underweight (Kurus)"
+        bmi < 25 -> "Normal"
+        bmi < 30 -> "Overweight (Gemuk)"
+        else -> "Obese (Obesitas)"
+    }
+}
+
+// ---------------- PREVIEWS ----------------
 @Preview(showBackground = true)
 @Composable
-fun TipTimeLayoutPreview() {
+fun HomeScreenPreview() {
-    TipTimeTheme {
+    TipTimeTheme { HomeScreen(onNavigateToCalculator = {}) }
-        TipTimeLayout()
+}
-    }
+
+@Preview(showBackground = true)
+@Composable
+fun BMICalculatorScreenPreview() {
+    TipTimeTheme { BMICalculatorScreen(onNavigateBack = {}) }
 }