/**
 * HelloComposeApp — minimal single-Activity Compose app.
 * Demonstrates: Activity -> setContent -> MaterialTheme -> Scaffold -> Composable.
 */

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.layout.*
import androidx.compose.material3.*
import androidx.compose.runtime.*
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.text.font.FontWeight
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.sp

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            MaterialTheme {
                Surface(color = MaterialTheme.colorScheme.background) {
                    HelloComposeApp()
                }
            }
        }
    }
}

@OptIn(ExperimentalMaterial3Api::class)
@Composable
fun HelloComposeApp() {
    Scaffold(topBar = { TopAppBar(title = { Text("Hello Compose") }) }) { padding ->
        Column(
            modifier = Modifier.fillMaxSize().padding(padding).padding(24.dp),
            horizontalAlignment = Alignment.CenterHorizontally,
            verticalArrangement = Arrangement.Center
        ) {
            Text("Welcome to SUZA", fontSize = 28.sp, fontWeight = FontWeight.Bold)
            Spacer(Modifier.height(8.dp))
            Text("Mobile Application Development", fontSize = 16.sp)
            Spacer(Modifier.height(24.dp))
            Greeting("Android")
        }
    }
}

@Composable
fun Greeting(name: String) {
    Text(text = "Hello, $name!", fontSize = 20.sp)
}

@Preview(showBackground = true)
@Composable
fun HelloPreview() { HelloComposeApp() }