Fastestvpn_JetpackCompose/app/src/main/java/com/vpn/fastestvpnservice/navigation/CustomBottomBarTV.kt

package com.vpn.fastestvpnservice.navigation

import android.util.Log
import androidx.activity.ComponentActivity
import androidx.compose.foundation.background
import androidx.compose.foundation.clickable
import androidx.compose.foundation.focusable
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.Row
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.size
import androidx.compose.material.Surface
import androidx.compose.material3.Icon
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.Scaffold
import androidx.compose.runtime.Composable
import androidx.compose.runtime.LaunchedEffect
import androidx.compose.runtime.MutableState
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableIntStateOf
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.draw.alpha
import androidx.compose.ui.focus.FocusRequester
import androidx.compose.ui.focus.focusRequester
import androidx.compose.ui.focus.onFocusChanged
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.res.colorResource
import androidx.compose.ui.res.painterResource
import androidx.compose.ui.unit.dp
import androidx.navigation.NavGraph.Companion.findStartDestination
import androidx.navigation.NavHostController
import androidx.navigation.compose.currentBackStackEntryAsState
import androidx.navigation.compose.rememberNavController
import com.vpn.fastestvpnservice.R
import com.vpn.fastestvpnservice.sealedClass.BottomBarScreen

val screens = listOf(
    BottomBarScreen.Home,
    BottomBarScreen.Settings,
    BottomBarScreen.Help,
    BottomBarScreen.Account
)

var isHomeScreenPressed: MutableState<Boolean> = mutableStateOf(true)
var isSettingsScreenPressed: MutableState<Boolean> = mutableStateOf(false)
var isHelpScreenPressed: MutableState<Boolean> = mutableStateOf(false)
var isAccountScreenPressed: MutableState<Boolean> = mutableStateOf(false)

var selectedItemIndex: MutableState<Int> = mutableIntStateOf(0)

var isFirstItemPressed: MutableState<Boolean> = mutableStateOf(false)
var isSecondItemPressed: MutableState<Boolean> = mutableStateOf(false)
var isThirdItemPressed: MutableState<Boolean> = mutableStateOf(false)
var isFourthItemPressed: MutableState<Boolean> = mutableStateOf(false)

var isFirstItemFocused: MutableState<Boolean> = mutableStateOf(false)
var isSecondItemFocused: MutableState<Boolean> = mutableStateOf(false)
var isThirdItemFocused: MutableState<Boolean> = mutableStateOf(false)
var isFourthItemFocused: MutableState<Boolean> = mutableStateOf(false)

@Composable
fun CustomBottomBarTV(navHostController: NavHostController, activity: ComponentActivity) {
    val navController1 = rememberNavController()
    var isBottomBarVisible by remember { mutableStateOf(true) }
//    var selectedItemIndex by remember { mutableIntStateOf(0) }
    var focusRequestersList = remember { List(screens.size) { FocusRequester() } }

    navController1.addOnDestinationChangedListener { _,_,_ ->
        isBottomBarVisible = navController1.currentDestination?.route in listOf(
            screens[0].route, screens[1].route, screens[2].route, screens[3].route)
    }

    Scaffold (
        modifier = Modifier.fillMaxSize(),
        bottomBar = {
            if (isBottomBarVisible) {
                BottomBarNavTV(
                    navHostController = navController1,
                    screens = screens
                )
            }
        },
        content = { padding ->
            Box(modifier = Modifier.padding(padding)) {
                BottomBarNavGraphTV(
                    navHostController = navController1,
                    settingsNavHostController = navHostController,
                    activity
                )
            }
        }
    )
}

@Composable
fun BottomBarNavTV(
    navHostController: NavHostController,
    screens: List<BottomBarScreen>
) {
//    var isFirstItemFocused by remember { mutableStateOf(false) }
//    var isSecondItemFocused by remember { mutableStateOf(false) }
//    var isThirdItemFocused by remember { mutableStateOf(false) }
//    var isFourthItemFocused by remember { mutableStateOf(false) }

    val focusRequester1 = remember { FocusRequester() }
    val focusRequester2 = remember { FocusRequester() }
    val focusRequester3 = remember { FocusRequester() }
    val focusRequester4 = remember { FocusRequester() }

    var isClicked by remember { mutableStateOf(false) }
    val navBackStackEntry = navHostController.currentBackStackEntryAsState()
    var currentDestination = navBackStackEntry.value?.destination
    var screen: BottomBarScreen = BottomBarScreen.Home
    val topPadding = 5.dp

    when (selectedItemIndex.value) {
        0 -> {
            screen = BottomBarScreen.Home
        }
        1 -> {
            screen = BottomBarScreen.Settings
        }
        2 -> {
            screen = BottomBarScreen.Help
        }
        3 -> {
            screen = BottomBarScreen.Account
        }
    }

    if (isClicked) {
        Log.d("test_bottom_navbar",
            "Before:: currentDestination -> " + currentDestination?.route + " -> " + screen.route + " " + selectedItemIndex.value
        )
        if (currentDestination?.route != screen.route) {
            Log.d("test_bottom_navbar",
                "currentDestination -> " + currentDestination?.route
                        + "Screen Clicked -> " + screen.route
            )

            LaunchedEffect(Unit) {
                navHostController.navigate(screen.route)
                {
                    popUpTo(
                        navHostController.graph
                            .findStartDestination().id) {
                        saveState = true
                    }
                    launchSingleTop = true
                }
            }
        }
        isClicked = false
    }

    if (isFirstItemPressed.value) {
        LaunchedEffect(key1 = Unit) {
            focusRequester1.requestFocus()
        }
        isFirstItemPressed.value = false
    }
    if (isSecondItemPressed.value) {
        LaunchedEffect(key1 = Unit) {
            focusRequester2.requestFocus()
        }
        isSecondItemPressed.value = false
    }
    if (isThirdItemPressed.value) {
        LaunchedEffect(key1 = Unit) {
            focusRequester3.requestFocus()
        }
        isThirdItemPressed.value = false
    }
    if (isFourthItemPressed.value) {
        LaunchedEffect(key1 = Unit) {
            focusRequester4.requestFocus()
        }
        isFourthItemPressed.value = false
    }

    Box(
        modifier = Modifier
            .fillMaxWidth()
            .background(MaterialTheme.colorScheme.background),
        contentAlignment = Alignment.Center
    ) {
        val iconSize = 45.dp
        Row(
            modifier = Modifier
                .height(55.dp)
                .fillMaxWidth(fraction = 0.4f)
                .padding(horizontal = 0.dp)
                .background(MaterialTheme.colorScheme.background),
            horizontalArrangement = Arrangement.SpaceBetween,
            verticalAlignment = Alignment.CenterVertically
        ) {
            Surface(
                color = if (isFirstItemFocused.value) MaterialTheme.colorScheme.outline
                else MaterialTheme.colorScheme.background,
                modifier = Modifier
                    .focusRequester(focusRequester1)
                    .onFocusChanged {
                        Log.d("is_focused", "1st")
                        isFirstItemFocused.value = it.isFocused

                        if (it.isFocused) {
                            Log.d("is_focused", "1st if")
                            selectedItemIndex.value = 0
                            isClicked = true
                        }

                    }
                    .focusable()
                    .clickable {
                        isHomeScreenPressed.value = true
                    }
            ) {
                val color = if (selectedItemIndex.value == 0) colorResource(id = R.color.blue_text)
                else MaterialTheme.colorScheme.primary
                val alpha = if (selectedItemIndex.value == 0) 1f else 0.5f
                Icon(
                    painter = painterResource(id = screens[0].icon),
                    contentDescription = "Navigation Icon",
                    tint = color,
                    modifier = Modifier
                        .size(iconSize)
                        .padding(top = topPadding, bottom = 4.dp)
                        .alpha(alpha)
                )
            }
            Surface(
                color = if (isSecondItemFocused.value) MaterialTheme.colorScheme.outline
                else MaterialTheme.colorScheme.background,
                modifier = Modifier
                    .focusRequester(focusRequester2)
                    .onFocusChanged {
                        Log.d("is_focused", "2nd")
                        isSecondItemFocused.value = it.isFocused

                        if (it.isFocused) {
                            Log.d("is_focused", "2nd if")
                            selectedItemIndex.value = 1
                            isClicked = true
                        }

                    }
                    .focusable()
                    .clickable {
                        isSettingsScreenPressed.value = true
                    }
            ) {
                val color = if (selectedItemIndex.value == 1) colorResource(id = R.color.blue_text)
                else MaterialTheme.colorScheme.primary
                val alpha = if (selectedItemIndex.value == 1) 1f else 0.5f
                Icon(
                    painter = painterResource(id = screens[1].icon),
                    contentDescription = "Navigation Icon",
                    tint = color,
                    modifier = Modifier
                        .size(iconSize)
                        .padding(top = topPadding, bottom = 4.dp)
                        .alpha(alpha)
                )
            }
            Surface(
                color = if (isThirdItemFocused.value) MaterialTheme.colorScheme.outline
                else MaterialTheme.colorScheme.background,
                modifier = Modifier
                    .focusRequester(focusRequester3)
                    .onFocusChanged {
                        Log.d("is_focused", "3rd")
                        isThirdItemFocused.value = it.isFocused

                        if (it.isFocused) {
                            Log.d("is_focused", "3rd if")
                            selectedItemIndex.value = 2
                            isClicked = true
                        }

                    }
                    .focusable()
                    .clickable {
                        isHelpScreenPressed.value = true
                    }
            ) {
                val color = if (selectedItemIndex.value == 2) colorResource(id = R.color.blue_text)
                else MaterialTheme.colorScheme.primary
                val alpha = if (selectedItemIndex.value == 2) 1f else 0.5f
                Icon(
                    painter = painterResource(id = screens[2].icon),
                    contentDescription = "Navigation Icon",
                    tint = color,
                    modifier = Modifier
                        .size(iconSize)
                        .padding(top = topPadding, bottom = 4.dp)
                        .alpha(alpha)
                )
            }
            Surface(
                color = if (isFourthItemFocused.value) MaterialTheme.colorScheme.outline
                else MaterialTheme.colorScheme.background,
                modifier = Modifier
                    .focusRequester(focusRequester4)
                    .onFocusChanged {
                        Log.d("is_focused", "4th")
                        isFourthItemFocused.value = it.isFocused
                        if (it.isFocused) {
                            Log.d("is_focused", "4th if")
                            selectedItemIndex.value = 3
                            isClicked = true
                        }

                    }
                    .focusable()
                    .clickable {
                        isAccountScreenPressed.value = true
                    }
            ) {
                val color = if (selectedItemIndex.value == 3) colorResource(id = R.color.blue_text)
                else MaterialTheme.colorScheme.primary
                val alpha = if (selectedItemIndex.value == 3) 1f else 0.5f
                Icon(
                    painter = painterResource(id = screens[3].icon),
                    contentDescription = "Navigation Icon",
                    tint = color,
                    modifier = Modifier
                        .size(iconSize)
                        .padding(top = topPadding, bottom = 4.dp)
                        .alpha(alpha)
                )
            }
        }
    }
}