package moe.nea.firmament.features.chat

import io.ktor.client.request.get
import io.ktor.client.statement.bodyAsChannel
import io.ktor.utils.io.jvm.javaio.toInputStream
import java.net.URL
import java.util.Collections
import moe.nea.jarvis.api.Point
import kotlinx.coroutines.Deferred
import kotlinx.coroutines.ExperimentalCoroutinesApi
import kotlinx.coroutines.async
import kotlin.math.min
import net.minecraft.client.gui.screen.ChatScreen
import net.minecraft.client.texture.NativeImage
import net.minecraft.client.texture.NativeImageBackedTexture
import net.minecraft.text.ClickEvent
import net.minecraft.text.HoverEvent
import net.minecraft.text.Style
import net.minecraft.text.Text
import net.minecraft.util.Formatting
import net.minecraft.util.Identifier
import moe.nea.firmament.Firmament
import moe.nea.firmament.annotations.Subscribe
import moe.nea.firmament.events.ModifyChatEvent
import moe.nea.firmament.events.ScreenRenderPostEvent
import moe.nea.firmament.features.FirmamentFeature
import moe.nea.firmament.gui.config.ManagedConfig
import moe.nea.firmament.util.MC
import moe.nea.firmament.util.transformEachRecursively
import moe.nea.firmament.util.unformattedString

object ChatLinks : FirmamentFeature {
    override val identifier: String
        get() = "chat-links"

    object TConfig : ManagedConfig(identifier) {
        val enableLinks by toggle("links-enabled") { true }
        val imageEnabled by toggle("image-enabled") { true }
        val allowAllHosts by toggle("allow-all-hosts") { false }
        val allowedHosts by string("allowed-hosts") { "cdn.discordapp.com,media.discordapp.com,media.discordapp.net,i.imgur.com" }
        val actualAllowedHosts get() = allowedHosts.split(",").map { it.trim() }
        val position by position("position", 16 * 20, 9 * 20) { Point(0.0, 0.0) }
    }

    private fun isHostAllowed(host: String) =
        TConfig.allowAllHosts || TConfig.actualAllowedHosts.any { it.equals(host, ignoreCase = true) }

    private fun isUrlAllowed(url: String) = isHostAllowed(url.removePrefix("https://").substringBefore("/"))

    override val config get() = TConfig
    val urlRegex = "https://[^. ]+\\.[^ ]+(\\.?( |$))".toRegex()

    data class Image(
        val texture: Identifier,
        val width: Int,
        val height: Int,
    )

    val imageCache: MutableMap<String, Deferred<Image?>> =
        Collections.synchronizedMap(mutableMapOf<String, Deferred<Image?>>())

    private fun tryCacheUrl(url: String) {
        if (!isUrlAllowed(url)) {
            return
        }
        if (url in imageCache) {
            return
        }
        imageCache[url] = Firmament.coroutineScope.async {
            try {
                val response = Firmament.httpClient.get(URL(url))
                if (response.status.value == 200) {
                    val inputStream = response.bodyAsChannel().toInputStream(Firmament.globalJob)
                    val image = NativeImage.read(inputStream)
                    val texture = MC.textureManager.registerDynamicTexture(
                        "dynamic_image_preview",
                        NativeImageBackedTexture(image)
                    )
                    Image(texture, image.width, image.height)
                } else
                    null
            } catch (exc: Exception) {
                exc.printStackTrace()
                null
            }
        }
    }

    val imageExtensions = listOf("jpg", "png", "gif", "jpeg")
    fun isImageUrl(url: String): Boolean {
        return (url.substringAfterLast('.').lowercase() in imageExtensions)
    }

    @Subscribe
    @OptIn(ExperimentalCoroutinesApi::class)
    fun onRender(it: ScreenRenderPostEvent) {
        if (!TConfig.imageEnabled) return
        if (it.screen !is ChatScreen) return
        val hoveredComponent =
            MC.inGameHud.chatHud.getTextStyleAt(it.mouseX.toDouble(), it.mouseY.toDouble()) ?: return
        val hoverEvent = hoveredComponent.hoverEvent ?: return
        val value = hoverEvent.getValue(HoverEvent.Action.SHOW_TEXT) ?: return
        val url = urlRegex.matchEntire(value.unformattedString)?.groupValues?.get(0) ?: return
        if (!isImageUrl(url)) return
        val imageFuture = imageCache[url] ?: return
        if (!imageFuture.isCompleted) return
        val image = imageFuture.getCompleted() ?: return
        it.drawContext.matrices.push()
        val pos = TConfig.position
        pos.applyTransformations(it.drawContext.matrices)
        val scale = min(1F, min((9 * 20F) / image.height, (16 * 20F) / image.width))
        it.drawContext.matrices.scale(scale, scale, 1F)
        it.drawContext.drawTexture(
            image.texture,
            0,
            0,
            1F,
            1F,
            image.width,
            image.height,
            image.width,
            image.height,
        )
        it.drawContext.matrices.pop()
    }

    @Subscribe
    fun onModifyChat(it: ModifyChatEvent) {
        if (!TConfig.enableLinks) return
        it.replaceWith = it.replaceWith.transformEachRecursively { child ->
            val text = child.string
            if ("://" !in text) return@transformEachRecursively child
            val s = Text.empty().setStyle(child.style)
            var index = 0
            while (index < text.length) {
                val nextMatch = urlRegex.find(text, index)
                if (nextMatch == null) {
                    s.append(Text.literal(text.substring(index, text.length)))
                    break
                }
                val range = nextMatch.groups[0]!!.range
                val url = nextMatch.groupValues[0]
                s.append(Text.literal(text.substring(index, range.first)))
                s.append(
                    Text.literal(url).setStyle(
                        Style.EMPTY.withUnderline(true).withColor(
                            Formatting.AQUA
                        ).withHoverEvent(HoverEvent(HoverEvent.Action.SHOW_TEXT, Text.literal(url)))
                            .withClickEvent(ClickEvent(ClickEvent.Action.OPEN_URL, url))
                    )
                )
                if (isImageUrl(url))
                    tryCacheUrl(url)
                index = range.last + 1
            }
            s
        }
    }
}