Add Advancements API

src/main/kotlin/io/github/dockyardmc/advancement/Advancement.kt

@@ -0,0 +1,188 @@
+package io.github.dockyardmc.advancement
+
+import cz.lukynka.bindables.BindableList
+import io.github.dockyardmc.events.EventPool
+import io.github.dockyardmc.events.PlayerLeaveEvent
+import io.github.dockyardmc.extentions.writeString
+import io.github.dockyardmc.extentions.writeStringArray
+import io.github.dockyardmc.extentions.writeTextComponent
+import io.github.dockyardmc.extentions.writeVarInt
+import io.github.dockyardmc.item.ItemStack
+import io.github.dockyardmc.player.Player
+import io.github.dockyardmc.protocol.NetworkWritable
+import io.github.dockyardmc.protocol.writeOptional
+import io.github.dockyardmc.registry.Items
+import io.github.dockyardmc.utils.Disposable
+import io.github.dockyardmc.utils.Viewable
+import io.netty.buffer.ByteBuf
+import kotlin.properties.Delegates
+
+class Advancement(
+    id: String,
+    parent: Advancement?,
+
+    title: String,
+    description: String,
+    icon: ItemStack,
+    frame: AdvancementFrame,
+    showToast: Boolean,
+    isHidden: Boolean,
+    background: String?,
+    x: Float,
+    y: Float,
+
+    requirements: List<List<String>>,
+) : NetworkWritable, Viewable(), Disposable {
+
+    var id by Delegates.observable(id) { _, _, _ -> update() }
+    var parent by Delegates.observable(parent) { _, _, _ -> update() }
+    val requirements = BindableList(requirements)
+
+    var title by Delegates.observable(title) { _, _, _ -> update() }
+    var description by Delegates.observable(description) { _, _, _ -> update() }
+    var icon by Delegates.observable(icon) { _, _, _ -> update() }
+    var frame by Delegates.observable(frame) { _, _, _ -> update() }
+    var showToast by Delegates.observable(showToast) { _, _, _ -> update() }
+    var isHidden by Delegates.observable(isHidden) { _, _, _ -> update() }
+    var background by Delegates.observable(background) { _, _, _ -> update() }
+    var x by Delegates.observable(x) { _, _, _ -> update() }
+    var y by Delegates.observable(y) { _, _, _ -> update() }
+
+    private val innerChildren = mutableListOf<Advancement>()
+    val children
+        get() = synchronized(innerChildren) {
+            innerChildren.toList()
+        }
+
+    override var autoViewable: Boolean = false
+
+    private val eventPool = EventPool()
+
+    init {
+        if (icon.material == Items.AIR) throw IllegalArgumentException("advancement icon can't be air")
+
+        parent?.innerChildren?.let {
+            synchronized(it) {
+                it.add(this)
+            }
+        }
+
+        this.requirements.listUpdated { update() }
+
+        eventPool.on<PlayerLeaveEvent> { event ->
+            removeViewer(event.player)
+        }
+    }
+
+    fun update() {
+        viewers.forEach { player ->
+            player.advancementTracker.onAdvancementRemoved(this)
+            player.advancementTracker.onAdvancementAdded(this)
+        }
+
+        children.forEach(Advancement::update)
+    }
+
+    override fun write(buffer: ByteBuf) {
+        buffer.writeOptional(parent?.id, ByteBuf::writeString)
+
+        // advancement display is present
+        buffer.writeBoolean(true)
+
+        buffer.writeTextComponent(title)
+        buffer.writeTextComponent(description)
+        icon.write(buffer)
+        buffer.writeVarInt(frame.ordinal)
+        buffer.writeInt(getFlags())
+        background?.let(buffer::writeString)
+        buffer.writeFloat(x)
+        buffer.writeFloat(y)
+
+        buffer.writeVarInt(requirements.size)
+        requirements.values.forEach(buffer::writeStringArray)
+
+        buffer.writeBoolean(false) // that's 'Sends telemetry' field
+    }
+
+    /**
+     * Adds the player as a viewer to this advancement
+     * and all parents, all the way to root
+     */
+    override fun addViewer(player: Player) {
+        if (viewers.contains(player)) return
+
+        // parents first
+        this.parent?.addViewer(player)
+
+        player.advancementTracker.onAdvancementAdded(this)
+        viewers.add(player)
+    }
+
+    /**
+     * Adds the player as a viewer
+     * to this advancement and ALL children
+     * recursively
+     */
+    fun addAll(player: Player) {
+        addViewer(player)
+
+        children.forEach { child ->
+            child.addAll(player)
+        }
+    }
+
+    /**
+     * Removes the player-viewer from this advancement
+     * and all children
+     */
+    override fun removeViewer(player: Player) {
+        if (!viewers.contains(player)) return
+
+        // children first
+        synchronized(this.innerChildren) {
+            this.innerChildren.forEach { child ->
+                child.removeViewer(player)
+            }
+        }
+
+        player.advancementTracker.onAdvancementRemoved(this)
+        viewers.remove(player)
+    }
+
+    fun getFlags(): Int {
+        var flags = 0x0
+        if (background != null) {
+            flags = flags or HAS_BACKGROUND_TEXTURE
+        }
+        if (showToast) {
+            flags = flags or SHOW_TOAST
+        }
+        if (isHidden) {
+            flags = flags or HIDDEN
+        }
+        return flags
+    }
+
+    companion object {
+        const val HAS_BACKGROUND_TEXTURE = 0x01
+        const val SHOW_TOAST = 0x02
+        const val HIDDEN = 0x04
+    }
+
+    /**
+     * Deletes this advancement and its children
+     */
+    override fun dispose() {
+        this.parent?.innerChildren?.remove(this)
+
+        while (viewers.isNotEmpty()) {
+            removeViewer(viewers.first())
+        }
+
+        while (innerChildren.isNotEmpty()) {
+            innerChildren.removeFirstOrNull()?.parent = null
+        }
+
+        this.parent = null
+    }
+}

src/main/kotlin/io/github/dockyardmc/advancement/AdvancementBuilder.kt

@@ -0,0 +1,113 @@
+package io.github.dockyardmc.advancement
+
+import io.github.dockyardmc.item.ItemStack
+import io.github.dockyardmc.maths.vectors.Vector2f
+import io.github.dockyardmc.registry.Items
+import io.github.dockyardmc.registry.registries.Item
+import io.github.dockyardmc.registry.registries.RegistryBlock
+
+/**
+ * Build the [Advancement]
+ */
+class AdvancementBuilder(val id: String) {
+    var parent: Advancement? = null
+    val requirements = mutableListOf<List<String>>()
+
+    var title: String = ""
+    var description: String = ""
+    var icon: ItemStack = Items.PAPER.toItemStack()
+    var frame: AdvancementFrame = AdvancementFrame.TASK
+    var showToast: Boolean = true
+    var isHidden: Boolean = false
+    var background: String? = null
+
+    var x: Float = 0f
+    var y: Float = 0f
+
+    fun withParent(parent: Advancement) {
+        this.parent = parent
+    }
+
+    fun withTitle(title: String) {
+        this.title = title
+    }
+
+    fun withDescription(description: String) {
+        this.description = description
+    }
+
+    fun withIcon(icon: ItemStack) {
+        this.icon = icon
+    }
+
+    fun withIcon(icon: Item) {
+        this.icon = icon.toItemStack()
+    }
+
+    fun withFrame(frame: AdvancementFrame) {
+        this.frame = frame
+    }
+
+    fun useToast(showToast: Boolean) {
+        this.showToast = showToast
+    }
+
+    fun withHidden(isHidden: Boolean) {
+        this.isHidden = isHidden
+    }
+
+    /**
+     * @param background path to a texture in minecraft resource pack
+     *
+     * Some examples:
+     * - `minecraft:textures/item/stick.png`
+     * - `minecraft:textures/block/netherrack.png`
+     * - `minecraft:textures/gui/book.png` (looks bad but works)
+     */
+    fun withBackground(background: String?) {
+        this.background = background
+    }
+
+    fun withBackground(block: RegistryBlock) {
+        val blockId = block.identifier.removePrefix("minecraft:")
+
+        // this is how it should be in 1.21.5
+        // "block/$blockId"
+        this.background = "minecraft:textures/block/$blockId.png"
+    }
+
+    fun withBackground(background: Item) {
+        val id = background.identifier.removePrefix("minecraft:")
+        this.background = "minecraft:textures/item/$id.png"
+    }
+
+    fun withPosition(x: Float, y: Float) {
+        this.x = x
+        this.y = y
+    }
+
+    fun withPosition(vec: Vector2f) {
+        this.x = vec.x
+        this.y = vec.y
+    }
+
+    fun withRequirement(req: String) {
+        this.requirements += listOf(req)
+    }
+
+    fun withRequirementsAnyOf(requirements: List<String>) {
+        this.requirements += requirements
+    }
+
+    fun build(): Advancement {
+        return Advancement(
+            id, parent, title, description, icon, frame, showToast, isHidden, background, x, y, requirements
+        )
+    }
+}
+
+fun advancement(id: String, builder: AdvancementBuilder.() -> Unit): Advancement {
+    val adv = AdvancementBuilder(id)
+    builder.invoke(adv)
+    return adv.build()
+}

src/main/kotlin/io/github/dockyardmc/advancement/AdvancementFrame.kt

@@ -0,0 +1,7 @@
+package io.github.dockyardmc.advancement
+
+enum class AdvancementFrame {
+    TASK,
+    CHALLENGE,
+    GOAL;
+}