package com.craigvg.lichun_android.ui.components.feedback

import androidx.compose.animation.core.Animatable
import androidx.compose.animation.core.tween
import androidx.compose.foundation.background
import androidx.compose.foundation.border
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material3.Text
import androidx.compose.runtime.*
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.alpha
import androidx.compose.ui.draw.clip
import androidx.compose.ui.draw.scale
import androidx.compose.ui.graphics.graphicsLayer
import androidx.compose.ui.unit.dp
import androidx.hilt.navigation.compose.hiltViewModel
import androidx.lifecycle.compose.collectAsStateWithLifecycle
import com.craigvg.lichun_android.domain.models.StatDelta
import com.craigvg.lichun_android.ui.theme.AppColors
import com.craigvg.lichun_android.ui.theme.AppSpacing
import com.craigvg.lichun_android.ui.theme.AppTypography
import com.craigvg.lichun_android.viewmodel.GameStateViewModel
import kotlinx.coroutines.delay

/**
 * Tier 3 polish: transient floating "+5 ⚡" / "-3 💰" chips that rise and fade
 * near the top of the screen when a lightweight "u" update changes a tracked
 * resource. Makes gains and losses feel earned.
 *
 * Android parity with iOS FloatingDeltaView / FloatingDeltaOverlay (T014). The
 * overlay observes [GameStateViewModel.statDeltas] and prunes each delta after it
 * finishes animating.
 */
@Composable
fun FloatingDeltaOverlay(
    gameStateViewModel: GameStateViewModel = hiltViewModel(),
    modifier: Modifier = Modifier
) {
    val deltas by gameStateViewModel.statDeltas.collectAsStateWithLifecycle()

    Box(modifier = modifier.fillMaxSize()) {
        Row(
            modifier = Modifier
                .align(Alignment.TopEnd)
                .padding(top = AppSpacing.xs, end = AppSpacing.md),
            horizontalArrangement = Arrangement.spacedBy(AppSpacing.xs)
        ) {
            deltas.forEach { delta ->
                key(delta.id) {
                    FloatingDeltaChip(
                        delta = delta,
                        onFinished = { gameStateViewModel.pruneStatDelta(delta.id) }
                    )
                }
            }
        }
    }
}

@Composable
private fun FloatingDeltaChip(delta: StatDelta, onFinished: () -> Unit) {
    val rise = remember { Animatable(0f) }
    val opacity = remember { Animatable(0f) }
    val scale = remember { Animatable(0.7f) }

    LaunchedEffect(delta.id) {
        // Pop in.
        opacity.animateTo(1f, tween(180))
        scale.animateTo(1f, tween(220))
        // Rise + linger.
        rise.animateTo(-36f, tween(1400))
        delay(200)
        opacity.animateTo(0f, tween(400))
        onFinished()
    }

    Row(
        modifier = Modifier
            .graphicsLayer { translationY = rise.value }
            .alpha(opacity.value)
            .scale(scale.value)
            .clip(RoundedCornerShape(AppSpacing.pillCornerRadius))
            .background(AppColors.surfaceElevated.copy(alpha = 0.92f))
            .border(1.dp, delta.kind.tint.copy(alpha = 0.35f), RoundedCornerShape(AppSpacing.pillCornerRadius))
            .padding(horizontal = AppSpacing.sm, vertical = AppSpacing.xxs),
        verticalAlignment = Alignment.CenterVertically
    ) {
        Text(delta.kind.emoji, style = AppTypography.caption)
        Spacer(Modifier.width(4.dp))
        Text(
            delta.label,
            style = AppTypography.captionBold,
            color = if (delta.amount > 0) delta.kind.tint else AppColors.error
        )
    }
}