Jetpack Compose Letter Spaced Persian Text

LetterSpacedPersianText.kt

@Composable
fun LetterSpacedPersianText(
    text: String,
    modifier: Modifier = Modifier,
    color: Color = Color.Unspecified,
    fontSize: TextUnit = 14.sp,
    fontStyle: FontStyle? = null,
    fontWeight: FontWeight? = null,
    fontFamily: FontFamily? = null,
    letterSpacing: TextUnit = TextUnit.Unspecified,
    textDecoration: TextDecoration? = null,
    textAlign: TextAlign? = null,
    lineHeight: TextUnit = TextUnit.Unspecified,
    overflow: TextOverflow = TextOverflow.Clip,
    softWrap: Boolean = true,
    maxLines: Int = Int.MAX_VALUE,
    onTextLayout: (TextLayoutResult) -> Unit = {},
    style: TextStyle = LocalTextStyle.current
) {
    val isPersian = remember { Regex("[ء-ی]") }
    val keshides = letterSpacing.value.toInt()
    val keshidesText = buildAnnotatedString { repeat(keshides) { append('ـ') } }
    val spacesText = buildAnnotatedString {
        repeat(keshides) {
            withStyle(style = SpanStyle(fontSize = fontSize.div(50 * letterSpacing.value))) {
                append(' ')
            }
        }
    }
    if (isPersian.containsMatchIn(text)) {
        if (text.length != 1) {
            val totalCursive = "ئبپتثجچحخسشصضطظعغفقکگلمنهی"
            val finalCursive = "أؤدذرزژو"
            val newText = buildAnnotatedString {
                var i = 0
                while (i < text.length) {
                    val current = text[i]
                    append(current)
                    val next = text.getOrNull(i + 1)
                    if (next != null) {
                        if (totalCursive.contains(current) && totalCursive.contains(next) ||
                            totalCursive.contains(current) && finalCursive.contains(next)
                        ) {
                            append(keshidesText)
                        }
                        if (current !in totalCursive && current !in finalCursive && next !in totalCursive && next !in finalCursive) {
                            append(spacesText)
                        }
                    }
                    i++
                }
            }
            Text(
                newText,
                modifier,
                color,
                fontSize,
                fontStyle,
                fontWeight,
                fontFamily,
                letterSpacing,
                textDecoration,
                textAlign,
                lineHeight,
                overflow,
                softWrap,
                maxLines,
                onTextLayout,
                style
            )
        } else {
            Text(
                text = text,
                modifier = modifier,
                color = color,
                fontSize = fontSize,
                fontStyle = fontStyle,
                fontWeight = fontWeight,
                fontFamily = fontFamily,
                letterSpacing = letterSpacing,
                textDecoration = textDecoration,
                textAlign = textAlign,
                lineHeight = lineHeight,
                overflow = overflow,
                softWrap = softWrap,
                maxLines = maxLines,
                onTextLayout = onTextLayout,
                style = style
            )
        }
    } else {
        Text(
            text = text,
            modifier = modifier,
            color = color,
            fontSize = fontSize,
            fontStyle = fontStyle,
            fontWeight = fontWeight,
            fontFamily = fontFamily,
            letterSpacing = letterSpacing,
            textDecoration = textDecoration,
            textAlign = textAlign,
            lineHeight = lineHeight,
            overflow = overflow,
            softWrap = softWrap,
            maxLines = maxLines,
            onTextLayout = onTextLayout,
            style = style
        )
    }
}