Merge pull request #70 from flytegg/gui-builder

GUI Builder

README.md

@@ -266,6 +266,58 @@ repeat(5, 10, TimeUnit.SECONDS, true) {
 
 > Twilight `repeat` conflicting with Kotlin's `repeat`? As an alternative, you can use `repeatingTask`. 
 
+### GUI Builder
+Creating GUI's can be an incredibly long and tedious process, however, in Twilight we offer a clean and efficient way to build GUIs.
+
+Here's an example of a simple, bog-standard GUI:
+```kotlin
+val basicGui = gui(Component.text("Click the apple!"), 9) {
+    set(4, ItemStack(Material.APPLE)) {
+        isCancelled = true
+        viewer.sendMessage(Component.text("This is an apple!"))
+    }
+}
+player.openInventory(basicGui)
+```
+As you can see, setting the click event logic has never been easier. You can reference the player at any time using `viewer`.
+
+Here's an example of a gui implementing the pattern feature, making it much easier to visualise:
+```kotlin
+val complexGui = gui {
+    pattern(
+        "#########",
+        "#   S   #",
+        "#########"
+    )
+
+    set('S', ItemStack(Material.PLAYER_HEAD).apply {
+        val meta = itemMeta as SkullMeta
+        meta.displayName(Component.text("${viewer.name}'s Head!"))
+        meta.owningPlayer = viewer
+        itemMeta = meta
+    }) {
+        isCancelled = true
+        viewer.sendMessage(Component.text("Ouch!", NamedTextColor.RED))
+    }
+
+    set('#', ItemStack(Material.LIGHT_GRAY_STAINED_GLASS_PANE).apply {
+        val meta = itemMeta
+        meta.displayName(Component.empty())
+        itemMeta = meta
+    }) { isCancelled = true }
+}
+player.openInventory(complexGui)
+```
+You can, of course, also implement GUIs for other inventory types:
+```kotlin
+val dropperGui = gui(Component.text("Title"), 9, InventoryType.DROPPER) {
+    // You can also set multiple indexes at once
+    set(listOf(1, 3, 4, 5, 7), ItemStack(Material.GRAY_STAINED_GLASS_PANE))
+}
+player.openInventory(dropperGui)
+```
+To open the gui, simply do `Player#openInventory(GUI)` like shown in the examples.
+
 ## Databases
 ### MongoDB
 Currently we have support for MongoDB. To configure it, you can take one of two routes:

src/main/kotlin/gg/flyte/twilight/gui/GUI.kt

@@ -0,0 +1,79 @@
+package gg.flyte.twilight.gui
+
+import gg.flyte.twilight.event.event
+import net.kyori.adventure.text.Component
+import org.bukkit.Bukkit
+import org.bukkit.entity.Player
+import org.bukkit.event.inventory.InventoryClickEvent
+import org.bukkit.event.inventory.InventoryType
+import org.bukkit.inventory.ItemStack
+
+inline fun gui(
+    title: Component = Component.text("Custom GUI"),
+    size: Int = 27,
+    type: InventoryType = InventoryType.CHEST,
+    noinline context: GUI.() -> Unit
+): GUI {
+    return GUI(title, size, type, context)
+}
+
+class GUI(val title: Component, val size: Int, val type: InventoryType, val context: GUI.() -> Unit) {
+
+    private val inventory = when (type) {
+        InventoryType.CHEST -> Bukkit.createInventory(null, size, title)
+        else -> Bukkit.createInventory(null, type, title)
+    }
+
+    private val keySlot = mutableMapOf<Char, MutableList<Int>>()
+    private val slotAction = mutableMapOf<Int, InventoryClickEvent.() -> Unit>()
+
+    lateinit var viewer: Player
+
+    private val clickEvent = event<InventoryClickEvent> {
+        if (inventory != this@GUI.inventory) return@event
+        slotAction[slot]?.invoke(this)
+    }
+
+    fun pattern(vararg pattern: String) {
+        for ((index, value) in pattern.joinToString("").withIndex()) {
+            keySlot.getOrPut(value) { mutableListOf() }.add(index)
+        }
+    }
+
+    @JvmName("setSlot")
+    fun set(slot: Int, item: ItemStack, action: InventoryClickEvent.() -> Unit = {}) {
+        inventory.setItem(slot, item)
+        slotAction[slot] = action
+    }
+
+    @JvmName("setSlots")
+    fun set(indexes: Collection<Int>, item: ItemStack, action: InventoryClickEvent.() -> Unit = {}) {
+        indexes.forEach { set(it, item, action) }
+    }
+
+    @JvmName("setKey")
+    fun set(key: Char, item: ItemStack, action: InventoryClickEvent.() -> Unit = {}) {
+        keySlot[key]?.forEach { set(it, item, action) }
+    }
+
+    @JvmName("setKeys")
+    fun set(keys: Collection<Char>, item: ItemStack, action: InventoryClickEvent.() -> Unit = {}) {
+        keys.forEach { set(it, item, action) }
+    }
+
+    private fun remove() {
+        keySlot.clear()
+        slotAction.clear()
+        inventory.clear()
+        clickEvent.unregister()
+    }
+
+    companion object {
+        fun Player.openInventory(gui: GUI) {
+            gui.viewer = this
+            gui.context.invoke(gui)
+            openInventory(gui.inventory)
+        }
+    }
+
+}