// GroceryItemsFromFile Example
// Source code file: MainActivity.kt
package it372.ssmith.groceryitemsfromfile
import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.activity.enableEdgeToEdge
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.rememberScrollState
import androidx.compose.foundation.verticalScroll
import androidx.compose.material3.Button
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.platform.LocalContext
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)
        enableEdgeToEdge()
        setContent {
            MainLayout()
        }
    }
}

@Composable
fun MainLayout( ) {

    // Keep track of the Text content.
    var textContent = remember { mutableStateOf("")  }

    // A Column needs a variable to keep track
    // of the scroll state.
    var scrollState = rememberScrollState( )

    Column(modifier = Modifier.padding(40.dp)
        .verticalScroll(scrollState)
        .fillMaxSize( )) {

        var grocList = mutableListOf<GroceryItem>( )
        val context = LocalContext.current
        val inputStream = context.resources.
            openRawResource(R.raw.groc)
        inputStream.bufferedReader( ).useLines {
            it.forEach {
                var fields = it.split(',')
                var desc = fields[0]
                var code = fields[1].toInt( )
                var price = fields[2].toDouble( )
                var grocItem = GroceryItem(desc, code, price)
                grocList.add(grocItem)
            }
        }
        Button(onClick = {
            var output = ""
            for(v in grocList) {
                output += "Description: ${v.description}\n" +
                    "Code: ${v.code}\n" +
                    "Price: ${v.price}\n\n"
            }
            textContent.value = output;
        }) {
            Text(text = "Show Grocery Items")
        }

        Text(text = textContent.value, modifier = Modifier
            .padding(40.dp),
            fontSize = 25.sp)
    }
}

@Preview(showBackground = true)
@Composable
fun GreetingPreview() {
    MainLayout( )
}