add quests stage change event, for #266

stages don't have IDs for some painful reason

src/main/java/com/denizenscript/depenizen/bukkit/events/quests/PlayerQuestStageChangeScriptEvent.java

@@ -0,0 +1,79 @@
+package com.denizenscript.depenizen.bukkit.events.quests;
+
+import com.denizenscript.denizen.events.BukkitScriptEvent;
+import com.denizenscript.denizen.objects.PlayerTag;
+import com.denizenscript.denizen.utilities.implementation.BukkitScriptEntryData;
+import com.denizenscript.denizencore.objects.ObjectTag;
+import com.denizenscript.denizencore.objects.core.ElementTag;
+import com.denizenscript.denizencore.scripts.ScriptEntryData;
+import com.denizenscript.denizencore.utilities.CoreUtilities;
+import me.blackvein.quests.events.quester.QuesterPostChangeStageEvent;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.Listener;
+
+public class PlayerQuestStageChangeScriptEvent extends BukkitScriptEvent implements Listener {
+
+    // <--[event]
+    // @Events
+    // quests player changes quest stage
+    // quests player changes <quest> stage
+    //
+    // @Regex ^on quests player changes [^\s]+ stage$
+    //
+    // @Cancellable true
+    //
+    // @Triggers when a player changes stage in a quest from the Quests plugin. Note that stages don't have unique IDs.
+    //
+    // @Context
+    // <context.quest> returns the ID of the quest.
+    //
+    // @Plugin Depenizen, Quests
+    //
+    // -->
+
+    public PlayerQuestStageChangeScriptEvent() {
+        instance = this;
+    }
+
+    public static PlayerQuestStageChangeScriptEvent instance;
+    public QuesterPostChangeStageEvent event;
+
+    @Override
+    public boolean couldMatch(ScriptPath path) {
+        return path.eventLower.startsWith("quests player changes");
+    }
+
+    @Override
+    public boolean matches(ScriptPath path) {
+        String questName = path.eventArgLowerAt(3);
+        if (!questName.equals("quest") && !questName.equals(CoreUtilities.toLowerCase(event.getQuest().getId()))) {
+            return false;
+        }
+
+        return true;
+    }
+
+    @Override
+    public String getName() {
+        return "QuestsPlayerQuestStageChange";
+    }
+
+    @Override
+    public ScriptEntryData getScriptEntryData() {
+        return new BukkitScriptEntryData(new PlayerTag(event.getQuester().getOfflinePlayer()), null);
+    }
+
+    @Override
+    public ObjectTag getContext(String name) {
+        if (name.equals("quest")) {
+            return new ElementTag(event.getQuest().getId());
+        }
+        return super.getContext(name);
+    }
+
+    @EventHandler
+    public void onQuestEvent(QuesterPostChangeStageEvent event) {
+        this.event = event;
+        fire(event);
+    }
+}