feat: Add basic ViewModel with name generation

app/src/main/java/cz/eman/android/interview/MainActivity.kt

@@ -3,19 +3,27 @@ package cz.eman.android.interview
 import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
+import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.WindowInsets
 import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.navigationBars
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.windowInsetsPadding
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.material3.Button
+import androidx.compose.material3.HorizontalDivider
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.text.style.TextAlign
 import androidx.core.view.WindowCompat
+import cz.eman.android.interview.repository.Repository
 
 class MainActivity : ComponentActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
@@ -37,16 +45,47 @@ class MainActivity : ComponentActivity() {
                                 .fillMaxSize()
                                 .padding(paddingValues)
                         ) {
-                            Text(
-                                modifier = Modifier.fillMaxSize(),
-                                textAlign = TextAlign.Center,
-                                color = Color.Blue,
-                                text = "Hello eMan candidate",
-                            )
+                            content(MainViewModel(Repository())) // DI will be done in next MR
                         }
                     }
                 )
             }
         }
     }
 }
+
+@Composable
+private fun content(
+    viewModel: MainViewModel,
+) {
+    Column {
+        Text(
+            modifier = Modifier.fillMaxWidth(),
+            textAlign = TextAlign.Center,
+            color = Color.Blue,
+            text = "Hello eMan candidate",
+        )
+
+        val data = viewModel.state.collectAsState()
+
+        Button(
+            onClick = {
+                viewModel.onClick()
+            }
+        ) {
+            Text(text = "Generate names with length ${data.value.number+1}")
+        }
+
+        Column {
+            data.value.names.forEachIndexed { index, name ->
+                Text(
+                    text = name
+                )
+
+                if (index < data.value.names.lastIndex) {
+                    HorizontalDivider()
+                }
+            }
+        }
+    }
+}

app/src/main/java/cz/eman/android/interview/MainViewModel.kt

@@ -0,0 +1,25 @@
+package cz.eman.android.interview
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import cz.eman.android.interview.repository.Repository
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.launch
+
+data class MainState(
+    val number: Int = 0,
+    val names: MutableList<String> = mutableListOf()
+)
+
+class MainViewModel(
+    private val repository: Repository
+): ViewModel() {
+    val state = MutableStateFlow(MainState())
+
+    fun onClick() {
+        viewModelScope.launch {
+            state.value = state.value.copy(number = state.value.number + 1)
+            state.value.names.apply { add("Name ${repository.getRandomName(state.value.number)}") }
+        }
+    }
+}

app/src/main/java/cz/eman/android/interview/repository/Repository.kt

@@ -0,0 +1,13 @@
+package cz.eman.android.interview.repository
+
+class Repository {
+    private fun getRandomString(length: Int) : String {
+        val allowedChars = ('A'..'Z') + ('a'..'z') + ('0'..'9')
+        return (1..length)
+            .map { allowedChars.random() }
+            .joinToString("")
+    }
+
+    fun getRandomName(length: Int) = getRandomString(
+        length)
+}