Add new AutoStartTimer using timer framework.

This commit only adds the new timer, but doesn't put it into use.

src/com/garbagemule/MobArena/util/timer/AutoStartTimer.java

@@ -0,0 +1,145 @@
+package com.garbagemule.MobArena.util.timer;
+
+import org.bukkit.entity.Player;
+
+import static com.garbagemule.MobArena.util.timer.Common.*;
+import com.garbagemule.MobArena.Messenger;
+import com.garbagemule.MobArena.Msg;
+import com.garbagemule.MobArena.framework.Arena;
+
+/**
+ * The AutoStartTimer is a self-contained CountdownTimer (i.e. it is its own
+ * callback), which force starts an arena (if the right conditions are met)
+ * when it finishes.
+ * <p>
+ * The timer is preprogrammed with a series of tick interval triggers, such
+ * that the timer only ticks when the time remaining matches one of these
+ * triggers. When the timer ticks, the lobby players are informed about the
+ * time remaining, and when the timer finishes, the arena is started. If the
+ * {@code display-timer-as-level} flag is set, the timer will tick once per
+ * second, updating the player levels.
+ * <p>
+ * The timer realizes a type of Null Object pattern if the duration of the
+ * timer (i.e. the value of the auto-start-timer setting) is 0, where calling
+ * the timer's methods does nothing.
+ */
+public class AutoStartTimer extends CountdownTimer implements TimerCallback {
+    private Arena arena;
+    private TimerCallback internalCallback;
+
+    /**
+     * Create an AutoStartTimer for the given arena.
+     * <p>
+     * The duration is determined from the {@code auto-start-timer} arena
+     * setting. If the setting is non-positive, the timer acts as a Null
+     * Object, allowing it to be safely used for arenas that do not have
+     * an auto-start-timer.
+     *
+     * @param arena the arena the timer is responsible for
+     */
+    public AutoStartTimer(Arena arena) {
+        super(arena.getPlugin());
+        super.setCallback(this);
+
+        this.arena = arena;
+
+        // Set the duration
+        long duration = arena.getSettings().getInt("auto-start-timer", 0) * 20l;
+        setDuration(Math.max(0l, duration));
+
+        // Choose level- or chat-callback
+        boolean level = arena.getSettings().getBoolean("display-timer-as-level", false);
+        internalCallback = level ? new LevelCallback() : new ChatCallback();
+    }
+
+    @Override
+    public synchronized void start() {
+        // Don't start if the arena doesn't actually have a timer
+        if (super.getDuration() > 0) {
+            super.start();
+        }
+    }
+
+    @Override
+    public void onStart() {
+        internalCallback.onStart();
+    }
+
+    @Override
+    public void onStop() {
+        internalCallback.onStop();
+    }
+
+    @Override
+    public void onTick() {
+        // TODO: Remove this if no one reports issues
+        if (arena.isRunning() || arena.getPlayersInLobby().isEmpty()) {
+            Messenger.severe("AUTO START TIMER WAS NOT STOPPED!");
+            Messenger.severe("  Please make a ticket and inform me about this at:");
+            Messenger.severe("  http://dev.bukkit.org/bukkit-plugins/mobarena/tickets/");
+            stop();
+            return;
+        }
+        internalCallback.onTick();
+    }
+
+    @Override
+    public void onFinish() {
+        arena.forceStart();
+    }
+
+    /**
+     * The LevelCallback is used for arenas that display the countdown as
+     * the player level, i.e. {@code display-timer-as-level: true}.
+     */
+    private class LevelCallback extends TimerCallbackAdapter {
+        public void onStart() {
+            setInterval(20);
+        }
+
+        public void onTick() {
+            int remaining = toSeconds(getRemaining());
+
+            for (Player p : arena.getPlayersInLobby()) {
+                p.setLevel(remaining);
+            }
+        }
+    }
+
+    /**
+     * The ChatCallback is used for arenas that announce the countdown in
+     * the chat periodically, i.e. {@code display-timer-as-level: false}.
+     */
+    private class ChatCallback extends TimerCallbackAdapter {
+        private int[] triggers = {30, 10, 5, 4, 3, 2, 1};
+        private int index = 0;
+
+        @Override
+        public void onStart() {
+            long duration = getDuration();
+
+            for (index = 0; index < triggers.length; index++) {
+                long trigger = toTicks(triggers[index]);
+                if (trigger < duration) {
+                    setInterval(duration - trigger);
+                    break;
+                }
+            }
+        }
+
+        @Override
+        public void onTick() {
+            // Announce remaining seconds
+            long ticks  = getRemaining();
+            int seconds = toSeconds(ticks);
+            Messenger.announce(arena, Msg.ARENA_AUTO_START, String.valueOf(seconds));
+
+            // Calculate the new interval
+            index++;
+            if (index < triggers.length) {
+                long trigger = toTicks(triggers[index]);
+                setInterval(ticks - trigger);
+            }
+        }
+    }
+}

src/com/garbagemule/MobArena/util/timer/ChatCallback.java

@@ -0,0 +1,61 @@
+package com.garbagemule.MobArena.util.timer;
+
+import com.garbagemule.MobArena.Messenger;
+import com.garbagemule.MobArena.Msg;
+import com.garbagemule.MobArena.framework.Arena;
+
+import static com.garbagemule.MobArena.util.timer.Common.toSeconds;
+import static com.garbagemule.MobArena.util.timer.Common.toTicks;
+
+/**
+ * The ChatCallback will periodically announce a message to all players in an
+ * arena, based on the tick interval triggers provided in the constructor.
+ * <p>
+ * The primary purpose of the class is to encapsulate the logic needed by e.g.
+ * the {@link AutoStartTimer}, when {@code display-timer-as-level: false}.
+ */
+public class ChatCallback extends TimerCallbackAdapter {
+    private Arena arena;
+    private Msg msg;
+    private CountdownTimer timer;
+
+    private int[] triggers;
+    private int index;
+
+    public ChatCallback(Arena arena, Msg msg, CountdownTimer timer, int[] triggers) {
+        this.arena = arena;
+        this.msg   = msg;
+        this.timer = timer;
+
+        this.triggers = triggers;
+        this.index = 0;
+    }
+
+    @Override
+    public void onStart() {
+        long duration = timer.getDuration();
+
+        for (index = 0; index < triggers.length; index++) {
+            long trigger = toTicks(triggers[index]);
+            if (trigger < duration) {
+                timer.setInterval(duration - trigger);
+                break;
+            }
+        }
+    }
+
+    @Override
+    public void onTick() {
+        // Announce remaining seconds
+        long ticks  = timer.getRemaining();
+        int seconds = toSeconds(ticks);
+        Messenger.announce(arena, msg, String.valueOf(seconds));
+
+        // Calculate the new interval
+        index++;
+        if (index < triggers.length) {
+            long trigger = toTicks(triggers[index]);
+            timer.setInterval(ticks - trigger);
+        }
+    }
+}

src/com/garbagemule/MobArena/util/timer/LevelCallback.java

@@ -0,0 +1,35 @@
+package com.garbagemule.MobArena.util.timer;
+
+import static com.garbagemule.MobArena.util.timer.Common.*;
+
+import com.garbagemule.MobArena.framework.Arena;
+import org.bukkit.entity.Player;
+
+/**
+ * The LevelCallback will display the countdown timer as the player level for
+ * all lobby players every second.
+ * <p>
+ * The primary purpose of the class is to encapsulate the logic needed by e.g.
+ * the {@link AutoStartTimer}, when {@code display-timer-as-level: true}.
+ */
+public class LevelCallback extends TimerCallbackAdapter {
+    private Arena arena;
+    private CountdownTimer timer;
+
+    public LevelCallback(Arena arena, CountdownTimer timer) {
+        this.arena = arena;
+        this.timer = timer;
+    }
+
+    public void onStart() {
+        timer.setInterval(20);
+    }
+
+    public void onTick() {
+        int remaining = toSeconds(timer.getRemaining());
+
+        for (Player p : arena.getPlayersInLobby()) {
+            p.setLevel(remaining);
+        }
+    }
+}