package mods.betterfoliage.client.texture

import mods.betterfoliage.BetterFoliageMod
import mods.octarinecore.client.resource.*
import mods.octarinecore.stripStart
import net.minecraft.util.ResourceLocation
import java.awt.image.BufferedImage

/**
 * Generate round leaf textures from leaf block textures.
 * The base texture is tiled 2x2, then parts of it are made transparent by applying a mask to the alpha channel.
 *
 * Generator parameter _type_: Leaf type (configurable by user). Different leaf types may have their own alpha mask.
 *
 * @param[domain] Resource domain of generator
 */
class LeafGenerator(domain: String) : TextureGenerator(domain) {

    override fun generate(params: ParameterList): BufferedImage? {
        val target = targetResource(params)!!
        val leafType = params["type"] ?: "default"

        val handDrawnLoc = target.second.stripStart("textures/").stripStart("blocks/").let {
            ResourceLocation(BetterFoliageMod.DOMAIN, "${it.namespace}/textures/blocks/${it.path}")
        }
        resourceManager[handDrawnLoc]?.loadImage()?.let { return it }

        val baseTexture = resourceManager[target.second]?.loadImage() ?: return null
        val size = baseTexture.width
        val frames = baseTexture.height / size

        val maskTexture = (getLeafMask(leafType, size * 2) ?: getLeafMask("default", size * 2))?.loadImage()
        fun scale(i: Int) = i * maskTexture!!.width / (size * 2)

        val leafTexture = BufferedImage(size * 2, size * 2 * frames, BufferedImage.TYPE_4BYTE_ABGR)
        val graphics = leafTexture.createGraphics()

        // iterate all frames
        for (frame in 0 .. frames - 1) {
            val baseFrame = baseTexture.getSubimage(0, size * frame, size, size)
            val leafFrame = BufferedImage(size * 2, size * 2, BufferedImage.TYPE_4BYTE_ABGR)

            // tile leaf texture 2x2
            leafFrame.createGraphics().apply {
                drawImage(baseFrame, 0, 0, null)
                drawImage(baseFrame, 0, size, null)
                drawImage(baseFrame, size, 0, null)
                drawImage(baseFrame, size, size, null)
            }

            // overlay alpha mask
            if (target.first == ResourceType.COLOR && maskTexture != null) {
                for (x in 0 .. size * 2 - 1) for (y in 0 .. size * 2 - 1) {
                    val basePixel = leafFrame[x, y].toLong() and 0xFFFFFFFFL
                    val maskPixel = maskTexture[scale(x), scale(y)].toLong() and 0xFF000000L or 0xFFFFFFL
                    leafFrame[x, y] = (basePixel and maskPixel).toInt()
                }
            }

            // add to animated png
            graphics.drawImage(leafFrame, 0, size * frame * 2, null)
        }

        return leafTexture
    }

    /**
     * Get the alpha mask to use
     *
     * @param[type] Alpha mask type.
     * @param[maxSize] Preferred mask size.
     */
    fun getLeafMask(type: String, maxSize: Int) = getMultisizeTexture(maxSize) { size ->
        ResourceLocation(BetterFoliageMod.DOMAIN, "textures/blocks/leafmask_${size}_${type}.png")
    }

}