textbinding.kt

sealed class TextRes {
	abstract val resId: Int

	data class Regular(
		override val resId: Int
	) : TextRes() {

		override fun equals(other: Any?): Boolean {
			if (this === other) return true
			if (other !is Regular) return false
			if (resId != other.resId) return false
			return true
		}

		override fun hashCode(): Int {
			return resId
		}
	}

	class Quantity(
		override val resId: Int,
		val quantity: Int,
		vararg values: Any?
	) : TextRes() {
		val args = values

		override fun equals(other: Any?): Boolean {
			if (this === other) return true
			if (other !is Quantity) return false
			if (resId != other.resId) return false
			if (quantity != other.quantity) return false
			if (!args.contentEquals(other.args)) return false

			return true
		}

		override fun hashCode(): Int {
			var result = resId
			result = 31 * result + quantity
			result = 31 * result + args.contentHashCode()
			return result
		}
	}


	class Formatted(
		override val resId: Int,
		vararg values: Any?
	) : TextRes() {
		val args = values

		override fun equals(other: Any?): Boolean {
			if (this === other) return true
			if (other !is Formatted) return false
			if (resId != other.resId) return false
			if (!args.contentEquals(other.args)) return false

			return true
		}

		override fun hashCode(): Int {
			var result = resId
			result = 31 * result + args.contentHashCode()
			return result
		}
	}
}

@SuppressWarnings("SpreadOperator", "NestedBlockDepth")
@BindingAdapter("textRes")
fun TextView.setTextRes(stringRes: TextRes?) {
	val newText = when (stringRes) {
		is TextRes.Regular -> context.getString(stringRes.resId)
		is TextRes.Formatted -> context.getString(stringRes.resId, *stringRes.args)
		is TextRes.Quantity -> context.resources.getQuantityString(stringRes.resId, stringRes.quantity, *stringRes.args)
		null -> ""
	}
	val oldText = text

	// save layout passes, should apply to all other
	if (haveContentsChanged(newText, oldText)) {
		text = newText
	}
}

@BindingAdapter("textRes")
fun TextView.setTextRes(stringRes: Int?) {
	val newText = if (stringRes != null && stringRes != 0) context.getString(stringRes) else ""
	val oldText = text

	// save layout passes, should apply to all other
	if (haveContentsChanged(newText, oldText)) {
		text = newText
	}
}

@BindingAdapter(value = ["spannableText", "links"], requireAll = true)
fun TextView.setSpannableLinks(spannable: String, links: HashMap<Int, () -> Unit>) {
	val span = SpannableStringBuilder(spannable)

	for ((link, callback) in links) {
		val customSpan = CustomClickableSpan(context, callback, currentTextColor)
		val linkSpan = resources.getString(link)
		val startLink = spannable.indexOf(linkSpan)
		val endLink = startLink + linkSpan.length

		if (startLink >= 0) span.setSpan(customSpan, startLink, endLink, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE)
	}

	text = span
}

@SuppressWarnings("ReturnCount")
private fun haveContentsChanged(str1: CharSequence?, str2: CharSequence?): Boolean {
	if (str1 == null != (str2 == null)) {
		return true
	} else if (str1 == null) {
		return false
	}
	val length = str1.length
	if (length != str2!!.length) {
		return true
	}
	for (i in 0 until length) {
		if (str1[i] != str2[i]) {
			return true
		}
	}
	return false
}