package link.roadio.riff.player.storage

import android.icu.lang.UCharacter
import android.icu.text.BreakIterator
import android.icu.text.Normalizer2
import java.util.Locale

internal fun normalizedPlaylistName(name: String): String {
    val trimmed = name.trim()
    require(trimmed.isNotEmpty() && graphemeCount(trimmed) <= PlayerStateStore.MAX_STRING_LENGTH)
    return UCharacter.foldCase(Normalizer2.getNFKCInstance().normalize(trimmed), true)
}

internal fun graphemeCount(value: String): Int =
    BreakIterator.getCharacterInstance(Locale.ROOT).let {
        it.setText(value)
        var count = 0
        while (it.next() !=
            BreakIterator.DONE
        ) {
            count++
        }
        count
    }

internal fun bookCollectionName(title: String): String {
    val source = title.trim().ifBlank { "Book" }
    val prefix = "Bookmarks for "
    val iterator = BreakIterator.getCharacterInstance(Locale.ROOT).apply { setText(source) }
    var end = 0
    repeat(PlayerStateStore.MAX_STRING_LENGTH - graphemeCount(prefix)) {
        val next = iterator.next()
        if (next ==
            BreakIterator.DONE
        ) {
            return prefix + source
        }
        end = next
    }
    return prefix + source.substring(0, end).trimEnd()
}