package moe.nea.firmament.features.inventory.storageoverlay

import me.shedaniel.math.Point
import me.shedaniel.math.Rectangle
import net.minecraft.client.gui.DrawContext
import net.minecraft.client.gui.screen.Screen
import net.minecraft.screen.slot.Slot
import net.minecraft.text.Text
import net.minecraft.util.Identifier
import moe.nea.firmament.util.MC
import moe.nea.firmament.util.assertTrueOr

class StorageOverlayScreen : Screen(Text.literal("")) {

	companion object {
		val PLAYER_WIDTH = 184
		val PLAYER_HEIGHT = 91
		val PLAYER_Y_INSET = 3
		val SLOT_SIZE = 18
		val PADDING = 10
		val PAGE_WIDTH = SLOT_SIZE * 9
		val HOTBAR_X = 12
		val HOTBAR_Y = 67
		val MAIN_INVENTORY_Y = 9
		val SCROLL_BAR_WIDTH = 8
		val SCROLL_BAR_HEIGHT = 16
	}

	var isExiting: Boolean = false
	var scroll: Float = 0F
	var pageWidthCount = StorageOverlay.TConfig.columns

	inner class Measurements {
		val innerScrollPanelWidth = PAGE_WIDTH * pageWidthCount + (pageWidthCount - 1) * PADDING
		val overviewWidth = innerScrollPanelWidth + 3 * PADDING + SCROLL_BAR_WIDTH
		val x = width / 2 - overviewWidth / 2
		val overviewHeight = minOf(3 * 18 * 6, height - PLAYER_HEIGHT - minOf(80, height / 10))
		val innerScrollPanelHeight = overviewHeight - PADDING * 2
		val y = height / 2 - (overviewHeight + PLAYER_HEIGHT) / 2
		val playerX = width / 2 - PLAYER_WIDTH / 2
		val playerY = y + overviewHeight - PLAYER_Y_INSET
		val totalWidth = overviewWidth
		val totalHeight = overviewHeight - PLAYER_Y_INSET + PLAYER_HEIGHT
	}

	var measurements = Measurements()

	var lastRenderedInnerHeight = 0
	public override fun init() {
		super.init()
		pageWidthCount = StorageOverlay.TConfig.columns
			.coerceAtMost((width - PADDING) / (PAGE_WIDTH + PADDING))
			.coerceAtLeast(1)
		measurements = Measurements()
		scroll = scroll.coerceAtMost(getMaxScroll()).coerceAtLeast(0F)
	}

	override fun mouseScrolled(
		mouseX: Double,
		mouseY: Double,
		horizontalAmount: Double,
		verticalAmount: Double
	): Boolean {
		scroll = (scroll + StorageOverlay.adjustScrollSpeed(verticalAmount)).toFloat()
			.coerceAtMost(getMaxScroll())
			.coerceAtLeast(0F)
		return true
	}

	fun getMaxScroll() = lastRenderedInnerHeight.toFloat() - getScrollPanelInner().height

	val playerInventorySprite = Identifier.of("firmament:storageoverlay/player_inventory")
	val upperBackgroundSprite = Identifier.of("firmament:storageoverlay/upper_background")
	val slotRowSprite = Identifier.of("firmament:storageoverlay/storage_row")
	val scrollbarBackground = Identifier.of("firmament:storageoverlay/scroll_bar_background")
	val scrollbarKnob = Identifier.of("firmament:storageoverlay/scroll_bar_knob")

	override fun close() {
		isExiting = true
		super.close()
	}

	override fun render(context: DrawContext, mouseX: Int, mouseY: Int, delta: Float) {
		super.render(context, mouseX, mouseY, delta)
		drawBackgrounds(context)
		drawPages(context, mouseX, mouseY, delta, null, null, Point())
		drawScrollBar(context)
		drawPlayerInventory(context, mouseX, mouseY, delta)
	}

	fun getScrollbarPercentage(): Float {
		return scroll / getMaxScroll()
	}

	fun drawScrollBar(context: DrawContext) {
		val sbRect = getScrollBarRect()
		context.drawGuiTexture(
			scrollbarBackground,
			sbRect.minX, sbRect.minY,
			sbRect.width, sbRect.height,
		)
		context.drawGuiTexture(
			scrollbarKnob,
			sbRect.minX, sbRect.minY + (getScrollbarPercentage() * (sbRect.height - SCROLL_BAR_HEIGHT)).toInt(),
			SCROLL_BAR_WIDTH, SCROLL_BAR_HEIGHT
		)
	}

	fun drawBackgrounds(context: DrawContext) {
		context.drawGuiTexture(upperBackgroundSprite,
		                       measurements.x,
		                       measurements.y,
		                       0,
		                       measurements.overviewWidth,
		                       measurements.overviewHeight)
		context.drawGuiTexture(playerInventorySprite,
		                       measurements.playerX,
		                       measurements.playerY,
		                       0,
		                       PLAYER_WIDTH,
		                       PLAYER_HEIGHT)
	}

	fun getPlayerInventorySlotPosition(int: Int): Pair<Int, Int> {
		if (int < 9) {
			return Pair(measurements.playerX + int * SLOT_SIZE + HOTBAR_X, HOTBAR_Y + measurements.playerY)
		}
		return Pair(
			measurements.playerX + (int % 9) * SLOT_SIZE + HOTBAR_X,
			measurements.playerY + (int / 9 - 1) * SLOT_SIZE + MAIN_INVENTORY_Y
		)
	}

	fun drawPlayerInventory(context: DrawContext, mouseX: Int, mouseY: Int, delta: Float) {
		val items = MC.player?.inventory?.main ?: return
		items.withIndex().forEach { (index, item) ->
			val (x, y) = getPlayerInventorySlotPosition(index)
			context.drawItem(item, x, y, 0)
			context.drawItemInSlot(textRenderer, item, x, y)
		}
	}

	fun getScrollBarRect(): Rectangle {
		return Rectangle(measurements.x + PADDING + measurements.innerScrollPanelWidth + PADDING,
		                 measurements.y + PADDING,
		                 SCROLL_BAR_WIDTH,
		                 measurements.innerScrollPanelHeight)
	}

	fun getScrollPanelInner(): Rectangle {
		return Rectangle(measurements.x + PADDING,
		                 measurements.y + PADDING,
		                 measurements.innerScrollPanelWidth,
		                 measurements.innerScrollPanelHeight)
	}

	fun createScissors(context: DrawContext) {
		val rect = getScrollPanelInner()
		context.enableScissor(
			rect.minX, rect.minY,
			rect.maxX, rect.maxY
		)
	}

	fun drawPages(
		context: DrawContext, mouseX: Int, mouseY: Int, delta: Float,
		excluding: StoragePageSlot?,
		slots: List<Slot>?,
		slotOffset: Point
	) {
		createScissors(context)
		val data = StorageOverlay.Data.data ?: StorageData()
		layoutedForEach(data) { rect, page, inventory ->
			drawPage(context,
			         rect.x,
			         rect.y,
			         page, inventory,
			         if (excluding == page) slots else null,
			         slotOffset
			)
		}
		context.disableScissor()
	}

	var knobGrabbed = false

	override fun mouseClicked(mouseX: Double, mouseY: Double, button: Int): Boolean {
		return mouseClicked(mouseX, mouseY, button, null)
	}

	override fun mouseReleased(mouseX: Double, mouseY: Double, button: Int): Boolean {
		if (knobGrabbed) {
			knobGrabbed = false
			return true
		}
		return super.mouseReleased(mouseX, mouseY, button)
	}

	override fun mouseDragged(mouseX: Double, mouseY: Double, button: Int, deltaX: Double, deltaY: Double): Boolean {
		if (knobGrabbed) {
			val sbRect = getScrollBarRect()
			val percentage = (mouseY - sbRect.getY()) / sbRect.getHeight()
			scroll = (getMaxScroll() * percentage).toFloat()
			mouseScrolled(0.0, 0.0, 0.0, 0.0)
			return true
		}
		return super.mouseDragged(mouseX, mouseY, button, deltaX, deltaY)
	}

	fun mouseClicked(mouseX: Double, mouseY: Double, button: Int, activePage: StoragePageSlot?): Boolean {
		if (getScrollPanelInner().contains(mouseX, mouseY)) {
			val data = StorageOverlay.Data.data ?: StorageData()
			layoutedForEach(data) { rect, page, _ ->
				if (rect.contains(mouseX, mouseY) && activePage != page && button == 0) {
					page.navigateTo()
					return true
				}
			}
			return false
		}
		val sbRect = getScrollBarRect()
		if (sbRect.contains(mouseX, mouseY)) {
			val percentage = (mouseY - sbRect.getY()) / sbRect.getHeight()
			scroll = (getMaxScroll() * percentage).toFloat()
			mouseScrolled(0.0, 0.0, 0.0, 0.0)
			knobGrabbed = true
			return true
		}
		return false
	}

	private inline fun layoutedForEach(
		data: StorageData,
		func: (
			rectangle: Rectangle,
			page: StoragePageSlot, inventory: StorageData.StorageInventory,
		) -> Unit
	) {
		var yOffset = -scroll.toInt()
		var xOffset = 0
		var maxHeight = 0
		for ((page, inventory) in data.storageInventories.entries) {
			val currentHeight = inventory.inventory?.let { it.rows * SLOT_SIZE + 4 + textRenderer.fontHeight }
				?: 18
			maxHeight = maxOf(maxHeight, currentHeight)
			val rect = Rectangle(
				measurements.x + PADDING + (PAGE_WIDTH + PADDING) * xOffset,
				yOffset + measurements.y + PADDING,
				PAGE_WIDTH,
				currentHeight
			)
			func(rect, page, inventory)
			xOffset++
			if (xOffset >= pageWidthCount) {
				yOffset += maxHeight
				xOffset = 0
				maxHeight = 0
			}
		}
		lastRenderedInnerHeight = maxHeight + yOffset + scroll.toInt()
	}

	fun drawPage(
		context: DrawContext,
		x: Int,
		y: Int,
		page: StoragePageSlot,
		inventory: StorageData.StorageInventory,
		slots: List<Slot>?,
		slotOffset: Point,
	): Int {
		val inv = inventory.inventory
		if (inv == null) {
			context.drawGuiTexture(upperBackgroundSprite, x, y, PAGE_WIDTH, 18)
			context.drawText(textRenderer,
			                 Text.literal("TODO: open this page"),
			                 x + 4,
			                 y + 4,
			                 -1,
			                 true)
			return 18
		}
		assertTrueOr(slots == null || slots.size == inv.stacks.size) { return 0 }
		val name = page.defaultName()
		context.drawText(textRenderer, Text.literal(name), x + 4, y + 2,
		                 if (slots == null) 0xFFFFFFFF.toInt() else 0xFFFFFF00.toInt(), true)
		context.drawGuiTexture(slotRowSprite, x, y + 4 + textRenderer.fontHeight, PAGE_WIDTH, inv.rows * SLOT_SIZE)
		inv.stacks.forEachIndexed { index, stack ->
			val slotX = (index % 9) * SLOT_SIZE + x + 1
			val slotY = (index / 9) * SLOT_SIZE + y + 4 + textRenderer.fontHeight + 1
			if (slots == null) {
				context.drawItem(stack, slotX, slotY)
				context.drawItemInSlot(textRenderer, stack, slotX, slotY)
			} else {
				val slot = slots[index]
				slot.x = slotX - slotOffset.x
				slot.y = slotY - slotOffset.y
			}
		}
		return inv.rows * SLOT_SIZE + 4 + textRenderer.fontHeight
	}

	fun getBounds(): List<Rectangle> {
		return listOf(
			Rectangle(measurements.x,
			          measurements.y,
			          measurements.overviewWidth,
			          measurements.overviewHeight),
			Rectangle(measurements.playerX,
			          measurements.playerY,
			          PLAYER_WIDTH,
			          PLAYER_HEIGHT))
	}
}