package com.radiola.ui.navigation

import androidx.compose.animation.AnimatedVisibility
import androidx.compose.animation.animateColorAsState
import androidx.compose.animation.core.tween
import androidx.compose.animation.expandHorizontally
import androidx.compose.animation.fadeIn
import androidx.compose.animation.fadeOut
import androidx.compose.animation.shrinkHorizontally
import androidx.compose.foundation.background
import androidx.compose.foundation.border
import androidx.compose.foundation.clickable
import androidx.compose.foundation.interaction.MutableInteractionSource
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.Spacer
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.width
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material3.Icon
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.remember
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
import androidx.compose.ui.unit.dp
import androidx.navigation.NavController
import androidx.navigation.compose.currentBackStackEntryAsState
import com.radiola.ui.theme.Motion
import com.radiola.ui.theme.RadiolaTheme

@Composable
fun BottomNavBar(navController: NavController) {
    val colors = RadiolaTheme.colors
    val currentRoute = navController.currentBackStackEntryAsState().value?.destination?.route
    // Обращаемся к объектам напрямую: companion-список NavDestinations.items
    // при холодном старте может содержать null (порядок инициализации Kotlin).
    val items = listOf(
        NavDestinations.Stations,
        NavDestinations.Favorites,
        NavDestinations.History,
        NavDestinations.Recordings,
        NavDestinations.Settings
    )

    Row(
        modifier = Modifier
            .fillMaxWidth()
            .padding(start = 16.dp, end = 16.dp, top = 8.dp, bottom = 16.dp)
            .clip(RoundedCornerShape(36.dp))
            .background(colors.surface2)
            .border(1.dp, colors.border, RoundedCornerShape(36.dp))
            .height(62.dp)
            .padding(6.dp),
        horizontalArrangement = Arrangement.spacedBy(4.dp),
        verticalAlignment = Alignment.CenterVertically
    ) {
        items.forEach { destination ->
            val selected = currentRoute == destination.route
            PillTab(
                label = destination.labelRes,
                icon = destination.icon,
                selected = selected,
                modifier = Modifier.weight(if (selected) 1.9f else 1f),
                onClick = {
                    if (currentRoute != destination.route) {
                        navController.navigate(destination.route) {
                            popUpTo(navController.graph.startDestinationId) { saveState = true }
                            launchSingleTop = true
                            restoreState = true
                        }
                    }
                }
            )
        }
    }
}

@Composable
private fun PillTab(
    label: String,
    icon: androidx.compose.ui.graphics.vector.ImageVector,
    selected: Boolean,
    onClick: () -> Unit,
    modifier: Modifier = Modifier
) {
    val colors = RadiolaTheme.colors
    val bg by animateColorAsState(
        targetValue = if (selected) colors.accent else androidx.compose.ui.graphics.Color.Transparent,
        animationSpec = tween(Motion.Medium),
        label = "tabBg"
    )
    val content by animateColorAsState(
        targetValue = if (selected) colors.bgBase else colors.textSecondary,
        animationSpec = tween(Motion.Medium),
        label = "tabFg"
    )
    Row(
        modifier = modifier
            .fillMaxWidth()
            .height(50.dp)
            .clip(RoundedCornerShape(26.dp))
            .background(bg)
            .clickable(
                interactionSource = remember { MutableInteractionSource() },
                indication = null,
                onClick = onClick
            ),
        horizontalArrangement = Arrangement.Center,
        verticalAlignment = Alignment.CenterVertically
    ) {
        Icon(
            imageVector = icon,
            contentDescription = label,
            tint = content,
            modifier = Modifier.height(18.dp).width(18.dp)
        )
        AnimatedVisibility(
            visible = selected,
            enter = fadeIn(tween(Motion.Medium)) + expandHorizontally(tween(Motion.Medium)),
            exit = fadeOut(tween(Motion.Fast)) + shrinkHorizontally(tween(Motion.Fast))
        ) {
            Row(verticalAlignment = Alignment.CenterVertically) {
                Spacer(Modifier.width(8.dp))
                Text(
                    text = label.uppercase(),
                    color = content,
                    style = androidx.compose.material3.MaterialTheme.typography.labelSmall,
                    maxLines = 1
                )
            }
        }
    }
}