From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Mon, 23 Nov 2020 12:58:16 -0800
Subject: [PATCH] Added PlayerLecternPageChangeEvent


diff --git a/src/main/java/io/papermc/paper/event/player/PlayerLecternPageChangeEvent.java b/src/main/java/io/papermc/paper/event/player/PlayerLecternPageChangeEvent.java
new file mode 100644
index 0000000000000000000000000000000000000000..6126182db48dab1286924f9642fb259087efabb3
--- /dev/null
+++ b/src/main/java/io/papermc/paper/event/player/PlayerLecternPageChangeEvent.java
@@ -0,0 +1,113 @@
+package io.papermc.paper.event.player;
+
+import org.bukkit.block.Lectern;
+import org.bukkit.entity.Player;
+import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.player.PlayerEvent;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.NullMarked;
+
+@NullMarked
+public class PlayerLecternPageChangeEvent extends PlayerEvent implements Cancellable {
+
+    private static final HandlerList HANDLER_LIST = new HandlerList();
+
+    private final Lectern lectern;
+    private final ItemStack book;
+    private final PageChangeDirection pageChangeDirection;
+    private final int oldPage;
+    private int newPage;
+
+    private boolean cancelled;
+
+    @ApiStatus.Internal
+    public PlayerLecternPageChangeEvent(final Player player, final Lectern lectern, final ItemStack book, final PageChangeDirection pageChangeDirection, final int oldPage, final int newPage) {
+        super(player);
+        this.lectern = lectern;
+        this.book = book;
+        this.pageChangeDirection = pageChangeDirection;
+        this.oldPage = oldPage;
+        this.newPage = newPage;
+    }
+
+    /**
+     * Gets the lectern involved.
+     *
+     * @return the Lectern
+     */
+    public Lectern getLectern() {
+        return this.lectern;
+    }
+
+    /**
+     * Gets the current ItemStack on the lectern.
+     *
+     * @return the ItemStack on the Lectern
+     */
+    public ItemStack getBook() {
+        return this.book;
+    }
+
+    /**
+     * Gets the page change direction. This is essentially returns which button the player clicked, left or right.
+     *
+     * @return the page change direction
+     */
+    public PageChangeDirection getPageChangeDirection() {
+        return this.pageChangeDirection;
+    }
+
+    /**
+     * Gets the page changed from. <i>Pages are 0-indexed.</i>
+     *
+     * @return the page changed from
+     */
+    public int getOldPage() {
+        return this.oldPage;
+    }
+
+    /**
+     * Gets the page changed to. <i>Pages are 0-indexed.</i>
+     *
+     * @return the page changed to
+     */
+    public int getNewPage() {
+        return this.newPage;
+    }
+
+    /**
+     * Sets the page changed to. <i>Pages are 0-indexed.</i>
+     * Page indices that are greater than the number of pages will show the last page.
+     *
+     * @param newPage the new paged changed to
+     */
+    public void setNewPage(final int newPage) {
+        this.newPage = newPage;
+    }
+
+    @Override
+    public boolean isCancelled() {
+        return this.cancelled;
+    }
+
+    @Override
+    public void setCancelled(final boolean cancel) {
+        this.cancelled = cancel;
+    }
+
+    @Override
+    public HandlerList getHandlers() {
+        return HANDLER_LIST;
+    }
+
+    public static HandlerList getHandlerList() {
+        return HANDLER_LIST;
+    }
+
+    public enum PageChangeDirection {
+        LEFT,
+        RIGHT,
+    }
+}