package com.peachpasswords.ui.components

import androidx.compose.animation.animateColorAsState
import androidx.compose.foundation.layout.Row
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableIntStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Shadow
import androidx.compose.ui.text.TextStyle
import androidx.compose.ui.text.font.FontStyle
import androidx.compose.ui.unit.sp
import com.peachpasswords.ui.theme.LocalPeachAccent
import com.peachpasswords.ui.theme.LocalReduceMotion
import com.peachpasswords.ui.theme.peachColors
import com.peachpasswords.ui.theme.PeachType
import kotlinx.coroutines.delay
import androidx.compose.runtime.LaunchedEffect
import kotlin.random.Random

private const val RUNE_COUNT = 9

/**
 * A faint row of PeachScript runes (Private Use Area glyphs). Mirrors the
 * browser LockRuneCanvas: ~13sp, text at 12% opacity, and one rune periodically
 * picks up the accent color with a soft glow before fading back.
 */
@Composable
fun LockRuneString(modifier: Modifier = Modifier) {
    val accent = LocalPeachAccent.current
    val reduceMotion = LocalReduceMotion.current
    val runes = remember {
        (0 until RUNE_COUNT).map { (0xE000 + Random.nextInt(256)).toChar().toString() }
    }
    var glowIdx by remember { mutableIntStateOf(-1) }

    if (!reduceMotion) {
        LaunchedEffect(Unit) {
            while (true) {
                delay(1500L + Random.nextLong(3000))
                glowIdx = Random.nextInt(RUNE_COUNT)
                delay(2000L + Random.nextLong(1500))
                glowIdx = -1
            }
        }
    }

    Row(modifier = modifier) {
        runes.forEachIndexed { idx, ch ->
            val glowing = idx == glowIdx
            val color by animateColorAsState(
                targetValue = if (glowing) accent else peachColors.T0.copy(alpha = 0.12f),
                label = "rune-glow",
            )
            Text(
                text = ch,
                color = color,
                style = TextStyle(
                    fontFamily = PeachType.Script,
                    fontStyle = FontStyle.Normal,
                    fontSize = 13.sp,
                    shadow = if (glowing) Shadow(color = accent, blurRadius = 12f) else null,
                ),
            )
        }
    }
}