package moe.nea.ledger

import net.minecraft.event.ClickEvent
import net.minecraft.event.HoverEvent
import net.minecraft.util.ChatComponentText
import net.minecraft.util.ChatStyle
import net.minecraft.util.EnumChatFormatting
import net.minecraft.util.IChatComponent
import java.time.Instant
import java.time.LocalDateTime
import java.time.ZoneId
import java.time.format.DateTimeFormatter
import java.time.format.DateTimeFormatterBuilder
import java.time.temporal.ChronoField
import java.util.regex.Matcher
import java.util.regex.Pattern

// language=regexp
val SHORT_NUMBER_PATTERN = "[0-9]+(?:,[0-9]+)*(?:\\.[0-9]+)?[kKmMbB]?"

// language=regexp
val ROMAN_NUMBER_PATTERN = "[IVXLCDM]+"

val romanNumbers = mapOf(
	'I' to 1,
	'V' to 5,
	'X' to 10,
	'L' to 50,
	'C' to 100,
	'D' to 500,
	'M' to 1000
)

fun parseRomanNumber(string: String): Int {
	var smallestSeenSoFar = Int.MAX_VALUE
	var lastSeenOfSmallest = 0
	var amount = 0
	for (c in string) {
		val cV = romanNumbers[c]!!
		if (cV == smallestSeenSoFar) {
			lastSeenOfSmallest++
			amount += cV
		} else if (cV < smallestSeenSoFar) {
			smallestSeenSoFar = cV
			amount += cV
			lastSeenOfSmallest = 1
		} else {
			amount -= lastSeenOfSmallest * smallestSeenSoFar * 2
			smallestSeenSoFar = cV
			amount += cV
			lastSeenOfSmallest = 1
		}
	}
	return amount
}

val siScalars = mapOf(
	'k' to 1_000.0,
	'K' to 1_000.0,
	'm' to 1_000_000.0,
	'M' to 1_000_000.0,
	'b' to 1_000_000_000.0,
	'B' to 1_000_000_000.0,
)

fun parseShortNumber(string: String): Double {
	var k = string.replace(",", "")
	val scalar = k.last()
	var scalarMultiplier = siScalars[scalar]
	if (scalarMultiplier == null) {
		scalarMultiplier = 1.0
	} else {
		k = k.dropLast(1)
	}
	return k.toDouble() * scalarMultiplier
}

fun Pattern.matches(string: String): Boolean = matcher(string).matches()
inline fun <T> Pattern.useMatcher(string: String, block: Matcher.() -> T): T? =
	matcher(string).takeIf { it.matches() }?.let(block)

fun <T> String.ifDropLast(suffix: String, block: (String) -> T): T? {
	if (endsWith(suffix)) {
		return block(dropLast(suffix.length))
	}
	return null
}

fun String.unformattedString(): String = replace("§.".toRegex(), "")

val timeFormat: DateTimeFormatter = DateTimeFormatterBuilder()
	.appendValue(ChronoField.DAY_OF_MONTH, 2)
	.appendLiteral(".")
	.appendValue(ChronoField.MONTH_OF_YEAR, 2)
	.appendLiteral(".")
	.appendValue(ChronoField.YEAR, 4)
	.appendLiteral(" ")
	.appendValue(ChronoField.HOUR_OF_DAY, 2)
	.appendLiteral(":")
	.appendValue(ChronoField.MINUTE_OF_HOUR, 2)
	.appendLiteral(":")
	.appendValue(ChronoField.SECOND_OF_MINUTE, 2)
	.toFormatter()

fun Instant.formatChat(): IChatComponent {
	val text = ChatComponentText(
		LocalDateTime.ofInstant(this, ZoneId.systemDefault()).format(timeFormat)
	)
	text.setChatStyle(
		ChatStyle()
			.setChatClickEvent(
				ClickEvent(ClickEvent.Action.OPEN_URL, "https://time.is/${this.epochSecond}"))
			.setChatHoverEvent(
				HoverEvent(HoverEvent.Action.SHOW_TEXT, ChatComponentText("Click to show on time.is")))
			.setColor(EnumChatFormatting.AQUA))
	return text
}