EventManager.java

package net.aufdemrand.denizen.events;

import net.aufdemrand.denizen.events.bukkit.ScriptReloadEvent;
import net.aufdemrand.denizen.events.core.*;
import net.aufdemrand.denizen.objects.aH;
import net.aufdemrand.denizen.objects.dNPC;
import net.aufdemrand.denizen.objects.dObject;
import net.aufdemrand.denizen.objects.dPlayer;
import net.aufdemrand.denizen.scripts.ScriptBuilder;
import net.aufdemrand.denizen.scripts.ScriptEntry;
import net.aufdemrand.denizen.scripts.commands.core.DetermineCommand;
import net.aufdemrand.denizen.scripts.containers.core.WorldScriptContainer;
import net.aufdemrand.denizen.scripts.queues.ScriptQueue;
import net.aufdemrand.denizen.scripts.queues.core.InstantQueue;
import net.aufdemrand.denizen.utilities.DenizenAPI;
import net.aufdemrand.denizen.utilities.debugging.dB;
import org.bukkit.Bukkit;
import org.bukkit.command.CommandMap;
import org.bukkit.command.PluginCommand;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.plugin.Plugin;
import org.bukkit.plugin.SimplePluginManager;

import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;

public class EventManager implements Listener {


    public EventManager() {
        DenizenAPI.getCurrentInstance().getServer().getPluginManager()
                .registerEvents(this, DenizenAPI.getCurrentInstance());
    }


    ///////////////////
    //  MAPS
    ////////////


    // Map for keeping the WorldScriptContainers
    public static Map<String, WorldScriptContainer> world_scripts =
            new ConcurrentHashMap<String, WorldScriptContainer>(8, 0.9f, 1);

    // Map for keeping the names of events
    public static Map<String, List<WorldScriptContainer>> events =
            new HashMap<String, List<WorldScriptContainer>>();

    // Map for keeping track of registered smart_events
    public static Set<SmartEvent> smart_events = new HashSet<SmartEvent>();



    //////////////////
    // PERFORMANCE
    ///////////


    @EventHandler
    public void scanWorldEvents(ScriptReloadEvent event) {
        // Build a Map of scripts keyed by 'world events name'.

        // Loop through each world script
        for (WorldScriptContainer script : world_scripts.values()) {
            if (script == null) continue;

            // ...and through each event inside the script.
            if (script.contains("EVENTS"))
                for (String eventName : script.getConfigurationSection("EVENTS").getKeys(false)) {
                    List<WorldScriptContainer> list;
                    if (events.containsKey(eventName))
                        list = events.get(eventName);
                    else
                        list = new ArrayList<WorldScriptContainer>();
                    list.add(script);
                    events.put(eventName, list);
                }
        }
        // dB.echoApproval("Built events map: " + events);

        // Breakdown all SmartEvents (if still being used, they will reinitialize next)
        for (SmartEvent smartEvent : smart_events)
                smartEvent.breakDown();

        // Pass these along to each SmartEvent so they can determine whether they can be enabled or not
        for (SmartEvent smartEvent : smart_events) {
            // If it should initialize, run _initialize!
            if (smartEvent.shouldInitialize(events.keySet()))
                smartEvent._initialize();

        }

        // TODO: Register any custom commands found with Bukkit

    }

    private Plugin plugin = DenizenAPI.getCurrentInstance();

    public void registerCommand(String... aliases) {
        PluginCommand command = getCommand(aliases[0], plugin);

        command.setAliases(Arrays.asList(aliases));
        getCommandMap().register(plugin.getDescription().getName(), command);
    }

    private static PluginCommand getCommand(String name, Plugin plugin) {
        PluginCommand command = null;

        try {
            Constructor<PluginCommand> c = PluginCommand.class.getDeclaredConstructor(String.class, Plugin.class);
            c.setAccessible(true);

            command = c.newInstance(name, plugin);
        } catch (Exception e) {
            dB.echoError(e);
        }

        return command;
    }

    private static CommandMap getCommandMap() {
        CommandMap commandMap = null;

        try {
            if (Bukkit.getPluginManager() instanceof SimplePluginManager) {
                Field f = SimplePluginManager.class.getDeclaredField("commandMap");
                f.setAccessible(true);

                commandMap = (CommandMap) f.get(Bukkit.getPluginManager());
            }
        } catch (NoSuchFieldException e) {
            dB.echoError(e);
        } catch (SecurityException e) {
            dB.echoError(e);
        } catch (IllegalArgumentException e) {
            dB.echoError(e);
        } catch (IllegalAccessException e) {
            dB.echoError(e);
        }

        return commandMap;
    }


    public static List<String> trimEvents(List<String> original) {
        List<String> event = new ArrayList<String>();
        event.addAll(original);
        List<String> parsed = new ArrayList<String>();

        if (dB.showEventsTrimming) dB.echoApproval("Trimming world events '" + event.toString() + '\'');

        // Remove any duplicate event names
        for (int i = 0; i < event.size(); i++) {
            for (int x = 0; x < event.size(); x++) {
                if (i != x && event.get(i).equalsIgnoreCase(event.get(x))) {
                    event.remove(i);
                    i--;
                    break;
                }
            }
        }

        // Create a new list, only containing events that have existing scripts
        for (String e : event)
            if (events.containsKey("ON " + e.toUpperCase()))
                parsed.add(e);

        return parsed;
    }



    ///////////////////
    //  COMPATIBILITY
    //////////////


    public static String doEvents(List<String> eventNames, dNPC npc, Player player, Map<String, dObject> context,
                                  boolean usesIdentifiers) {

        // If a list of events uses identifiers, also add those events to the list
        // with their identifiers stripped
        return doEvents(usesIdentifiers ? addAlternates(eventNames)
                : eventNames,
                npc, player, context);
    }


    public static List<String> addAlternates(List<String> events) {

        // Strip object identifiers from world event names and add the results
        // to the original list of world event names without any duplicates

        Set<String> newEvents = new HashSet<String>();

        for (String event : events) {
            if (event.matches(".*?[a-z]{1,2}@[\\w ]+")) {
                newEvents.add(event.replaceAll("[a-z]{1,2}@", ""));
            }
        }

        List<String> finalEvents = new ArrayList<String>();
        finalEvents.addAll(events);
        finalEvents.addAll(newEvents);
        return finalEvents;
    }



    ///////////////////
    //  MECHANICS
    ///////////////


    public static String doEvents(List<String> eventNames, dNPC npc, Player player, Map<String, dObject> context) {

        String determination = "none";

        // Trim again to catch events that don't trim internally.
        eventNames = trimEvents(eventNames);

        for (String eventName : eventNames) {

            if (events.containsKey("ON " + eventName.toUpperCase()))

                for (WorldScriptContainer script : events.get("ON " + eventName.toUpperCase())) {

                    if (script == null) continue;

                    // Fetch script from Event
                    //
                    // Note: a "new dPlayer(null)" will not be null itself,
                    //       so keep a ternary operator here
                    List<ScriptEntry> entries = script.getEntries
                            (player != null ? new dPlayer(player) : null,
                                    npc, "events.on " + eventName);

                    if (entries.isEmpty()) continue;

                    dB.report(script, "Event",
                            aH.debugObj("Type", "on " + eventName)
                                    + script.getAsScriptArg().debug()
                                    + (npc != null ? aH.debugObj("NPC", npc.toString()) : "")
                                    + (player != null ? aH.debugObj("Player", player.getName()) : "")
                                    + (context != null ? aH.debugObj("Context", context.toString()) : ""));

                    dB.echoDebug(script, dB.DebugElement.Header, "Building event 'ON " + eventName.toUpperCase()
                            + "' for " + script.getName());

                    // Create new ID -- this is what we will look for when determining an outcome
                    long id = DetermineCommand.getNewId();

                    // Add the reqId to each of the entries for the determine command
                    ScriptBuilder.addObjectToEntries(entries, "ReqId", id);

                    // Add entries and context to the queue
                    ScriptQueue queue = InstantQueue.getQueue(null).addEntries(entries);

                    if (context != null) {
                        for (Map.Entry<String, dObject> entry : context.entrySet()) {
                            queue.addContext(entry.getKey(), entry.getValue());
                        }
                    }

                    // Start the queue!
                    queue.start();

                    // Check the determination
                    if (DetermineCommand.hasOutcome(id))
                        determination =  DetermineCommand.getOutcome(id);
                }
        }

        return determination;
    }



    ////////////////////
    //  REGISTRATION
    //////////////


    public void registerCoreMembers() {
        // Register all the 'Core' SmartEvents. This is called by Denizen's onEnable().
        registerSmartEvent(new EntitySpawnSmartEvent());
        registerSmartEvent(new CuboidEnterExitSmartEvent());
        registerSmartEvent(new PlayerJumpSmartEvent());
    }


    public static void registerSmartEvent(SmartEvent event) {
        // Seems simple enough
        if (event != null)
            smart_events.add(event);
    }


}