Start implementing activity log feature

31 files changed, 903 insertions, 265 deletions

diff --git a/spark-bukkit/build.gradle b/spark-bukkit/build.gradle
index e8c6721..836e389 100644
--- a/spark-bukkit/build.gradle
+++ b/spark-bukkit/build.gradle
@@ -1,6 +1,8 @@
 dependencies {
     compile project(':spark-common')
-    compile 'net.kyori:text-adapter-bukkit:1.0.3'
+    compile('net.kyori:text-adapter-bukkit:1.0.3') {
+        exclude(module: 'text')
+    }
     compileOnly 'org.spigotmc:spigot-api:1.12.2-R0.1-SNAPSHOT'
 }
 
diff --git a/spark-bukkit/src/main/java/me/lucko/spark/bukkit/BukkitCommandSender.java b/spark-bukkit/src/main/java/me/lucko/spark/bukkit/BukkitCommandSender.java
new file mode 100644
index 0000000..dacea76
--- /dev/null
+++ b/spark-bukkit/src/main/java/me/lucko/spark/bukkit/BukkitCommandSender.java
@@ -0,0 +1,61 @@
+/*
+ * This file is part of spark.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package me.lucko.spark.bukkit;
+
+import me.lucko.spark.common.CommandSender;
+import net.kyori.text.Component;
+import net.kyori.text.adapter.bukkit.TextAdapter;
+
+public class BukkitCommandSender implements CommandSender {
+    private final org.bukkit.command.CommandSender sender;
+
+    public BukkitCommandSender(org.bukkit.command.CommandSender sender) {
+        this.sender = sender;
+    }
+
+    @Override
+    public String getName() {
+        return this.sender.getName();
+    }
+
+    @Override
+    public void sendMessage(Component message) {
+        TextAdapter.sendComponent(this.sender, message);
+    }
+
+    @Override
+    public boolean hasPermission(String permission) {
+        return this.sender.hasPermission(permission);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        BukkitCommandSender that = (BukkitCommandSender) o;
+        return this.sender.equals(that.sender);
+    }
+
+    @Override
+    public int hashCode() {
+        return this.sender.hashCode();
+    }
+}
diff --git a/spark-bukkit/src/main/java/me/lucko/spark/bukkit/SparkBukkitPlugin.java b/spark-bukkit/src/main/java/me/lucko/spark/bukkit/SparkBukkitPlugin.java
index 15c725d..ee85c70 100644
--- a/spark-bukkit/src/main/java/me/lucko/spark/bukkit/SparkBukkitPlugin.java
+++ b/spark-bukkit/src/main/java/me/lucko/spark/bukkit/SparkBukkitPlugin.java
@@ -20,29 +20,27 @@
 
 package me.lucko.spark.bukkit;
 
+import me.lucko.spark.common.CommandSender;
 import me.lucko.spark.common.SparkPlatform;
 import me.lucko.spark.common.SparkPlugin;
 import me.lucko.spark.common.command.CommandResponseHandler;
 import me.lucko.spark.common.monitor.tick.TpsCalculator;
 import me.lucko.spark.common.sampler.ThreadDumper;
 import me.lucko.spark.common.sampler.TickCounter;
-import net.kyori.text.Component;
 import net.kyori.text.TextComponent;
-import net.kyori.text.adapter.bukkit.TextAdapter;
 import org.bukkit.ChatColor;
 import org.bukkit.command.Command;
-import org.bukkit.command.CommandSender;
 import org.bukkit.plugin.java.JavaPlugin;
 
 import java.nio.file.Path;
-import java.util.Collections;
-import java.util.HashSet;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.Set;
+import java.util.stream.Collectors;
 
-public class SparkBukkitPlugin extends JavaPlugin implements SparkPlugin<CommandSender> {
+public class SparkBukkitPlugin extends JavaPlugin implements SparkPlugin {
 
-    private final SparkPlatform<CommandSender> platform = new SparkPlatform<>(this);
+    private final SparkPlatform platform = new SparkPlatform(this);
 
     @Override
     public void onEnable() {
@@ -56,7 +54,7 @@ public class SparkBukkitPlugin extends JavaPlugin implements SparkPlugin<Command
                     return true;
                 }
 
-                CommandResponseHandler<CommandSender> resp = new CommandResponseHandler<>(this.platform, sender);
+                CommandResponseHandler resp = new CommandResponseHandler(this.platform, new BukkitCommandSender(sender));
                 TpsCalculator tpsCalculator = this.platform.getTpsCalculator();
                 resp.replyPrefixed(TextComponent.of("TPS from last 5s, 10s, 1m, 5m, 15m:"));
                 resp.replyPrefixed(TextComponent.builder(" ").append(tpsCalculator.toFormattedComponent()).build());
@@ -71,22 +69,14 @@ public class SparkBukkitPlugin extends JavaPlugin implements SparkPlugin<Command
     }
 
     @Override
-    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
-        if (!sender.hasPermission("spark")) {
-            sender.sendMessage(ChatColor.RED + "You do not have permission to use this command.");
-            return true;
-        }
-
-        this.platform.executeCommand(sender, args);
+    public boolean onCommand(org.bukkit.command.CommandSender sender, Command command, String label, String[] args) {
+        this.platform.executeCommand(new BukkitCommandSender(sender), args);
         return true;
     }
 
     @Override
-    public List<String> onTabComplete(CommandSender sender, Command command, String alias, String[] args) {
-        if (!sender.hasPermission("spark")) {
-            return Collections.emptyList();
-        }
-        return this.platform.tabCompleteCommand(sender, args);
+    public List<String> onTabComplete(org.bukkit.command.CommandSender sender, Command command, String alias, String[] args) {
+        return this.platform.tabCompleteCommand(new BukkitCommandSender(sender), args);
     }
 
     @Override
@@ -106,15 +96,10 @@ public class SparkBukkitPlugin extends JavaPlugin implements SparkPlugin<Command
 
     @Override
     public Set<CommandSender> getSendersWithPermission(String permission) {
-        Set<CommandSender> senders = new HashSet<>(getServer().getOnlinePlayers());
+        List<org.bukkit.command.CommandSender> senders = new LinkedList<>(getServer().getOnlinePlayers());
         senders.removeIf(sender -> !sender.hasPermission(permission));
         senders.add(getServer().getConsoleSender());
-        return senders;
-    }
-
-    @Override
-    public void sendMessage(CommandSender sender, Component message) {
-        TextAdapter.sendComponent(sender, message);
+        return senders.stream().map(BukkitCommandSender::new).collect(Collectors.toSet());
     }
 
     @Override
diff --git a/spark-bungeecord/build.gradle b/spark-bungeecord/build.gradle
index 55dcb4e..5ee50d7 100644
--- a/spark-bungeecord/build.gradle
+++ b/spark-bungeecord/build.gradle
@@ -1,6 +1,8 @@
 dependencies {
     compile project(':spark-common')
-    compile 'net.kyori:text-adapter-bungeecord:1.0.3'
+    compile('net.kyori:text-adapter-bungeecord:1.0.3') {
+        exclude(module: 'text')
+    }
     compileOnly 'net.md-5:bungeecord-api:1.12-SNAPSHOT'
 }
 
diff --git a/spark-bungeecord/src/main/java/me/lucko/spark/bungeecord/BungeeCordCommandSender.java b/spark-bungeecord/src/main/java/me/lucko/spark/bungeecord/BungeeCordCommandSender.java
new file mode 100644
index 0000000..d3a831c
--- /dev/null
+++ b/spark-bungeecord/src/main/java/me/lucko/spark/bungeecord/BungeeCordCommandSender.java
@@ -0,0 +1,61 @@
+/*
+ * This file is part of spark.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package me.lucko.spark.bungeecord;
+
+import me.lucko.spark.common.CommandSender;
+import net.kyori.text.Component;
+import net.kyori.text.adapter.bungeecord.TextAdapter;
+
+public class BungeeCordCommandSender implements CommandSender {
+    private final net.md_5.bungee.api.CommandSender sender;
+
+    public BungeeCordCommandSender(net.md_5.bungee.api.CommandSender sender) {
+        this.sender = sender;
+    }
+
+    @Override
+    public String getName() {
+        return this.sender.getName();
+    }
+
+    @Override
+    public void sendMessage(Component message) {
+        TextAdapter.sendComponent(this.sender, message);
+    }
+
+    @Override
+    public boolean hasPermission(String permission) {
+        return this.sender.hasPermission(permission);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        BungeeCordCommandSender that = (BungeeCordCommandSender) o;
+        return this.sender.equals(that.sender);
+    }
+
+    @Override
+    public int hashCode() {
+        return this.sender.hashCode();
+    }
+}
diff --git a/spark-bungeecord/src/main/java/me/lucko/spark/bungeecord/SparkBungeeCordPlugin.java b/spark-bungeecord/src/main/java/me/lucko/spark/bungeecord/SparkBungeeCordPlugin.java
index ba2ee99..193ae06 100644
--- a/spark-bungeecord/src/main/java/me/lucko/spark/bungeecord/SparkBungeeCordPlugin.java
+++ b/spark-bungeecord/src/main/java/me/lucko/spark/bungeecord/SparkBungeeCordPlugin.java
@@ -20,27 +20,24 @@
 
 package me.lucko.spark.bungeecord;
 
+import me.lucko.spark.common.CommandSender;
 import me.lucko.spark.common.SparkPlatform;
 import me.lucko.spark.common.SparkPlugin;
 import me.lucko.spark.common.sampler.ThreadDumper;
 import me.lucko.spark.common.sampler.TickCounter;
-import net.kyori.text.Component;
-import net.kyori.text.adapter.bungeecord.TextAdapter;
-import net.md_5.bungee.api.ChatColor;
-import net.md_5.bungee.api.CommandSender;
-import net.md_5.bungee.api.chat.TextComponent;
 import net.md_5.bungee.api.plugin.Command;
 import net.md_5.bungee.api.plugin.Plugin;
 import net.md_5.bungee.api.plugin.TabExecutor;
 
 import java.nio.file.Path;
-import java.util.Collections;
-import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.List;
 import java.util.Set;
+import java.util.stream.Collectors;
 
-public class SparkBungeeCordPlugin extends Plugin implements SparkPlugin<CommandSender> {
+public class SparkBungeeCordPlugin extends Plugin implements SparkPlugin {
 
-    private final SparkPlatform<CommandSender> platform = new SparkPlatform<>(this);
+    private final SparkPlatform platform = new SparkPlatform(this);
 
     @Override
     public void onEnable() {
@@ -70,15 +67,10 @@ public class SparkBungeeCordPlugin extends Plugin implements SparkPlugin<Command
 
     @Override
     public Set<CommandSender> getSendersWithPermission(String permission) {
-        Set<CommandSender> senders = new HashSet<>(getProxy().getPlayers());
+        List<net.md_5.bungee.api.CommandSender> senders = new LinkedList<>(getProxy().getPlayers());
         senders.removeIf(sender -> !sender.hasPermission(permission));
         senders.add(getProxy().getConsole());
-        return senders;
-    }
-
-    @Override
-    public void sendMessage(CommandSender sender, Component message) {
-        TextAdapter.sendComponent(sender, message);
+        return senders.stream().map(BungeeCordCommandSender::new).collect(Collectors.toSet());
     }
 
     @Override
@@ -105,23 +97,13 @@ public class SparkBungeeCordPlugin extends Plugin implements SparkPlugin<Command
         }
 
         @Override
-        public void execute(CommandSender sender, String[] args) {
-            if (!sender.hasPermission("spark")) {
-                TextComponent msg = new TextComponent("You do not have permission to use this command.");
-                msg.setColor(ChatColor.RED);
-                sender.sendMessage(msg);
-                return;
-            }
-
-            this.plugin.platform.executeCommand(sender, args);
+        public void execute(net.md_5.bungee.api.CommandSender sender, String[] args) {
+            this.plugin.platform.executeCommand(new BungeeCordCommandSender(sender), args);
         }
 
         @Override
-        public Iterable<String> onTabComplete(CommandSender sender, String[] args) {
-            if (!sender.hasPermission("spark")) {
-                return Collections.emptyList();
-            }
-            return this.plugin.platform.tabCompleteCommand(sender, args);
+        public Iterable<String> onTabComplete(net.md_5.bungee.api.CommandSender sender, String[] args) {
+            return this.plugin.platform.tabCompleteCommand(new BungeeCordCommandSender(sender), args);
         }
     }
 }
diff --git a/spark-common/build.gradle b/spark-common/build.gradle
index a8b95c6..8a9ee16 100644
--- a/spark-common/build.gradle
+++ b/spark-common/build.gradle
@@ -1,7 +1,16 @@
 dependencies {
     compile 'com.squareup.okhttp3:okhttp:3.14.1'
     compile 'com.squareup.okio:okio:1.17.3'
-    compile 'net.kyori:text-api:2.0.0'
+    compile('net.kyori:text-api:2.0.0') {
+        exclude(module: 'checker-qual')
+    }
+    compile('net.kyori:text-serializer-gson:2.0.0') {
+        exclude(module: 'text-api')
+        exclude(module: 'gson')
+    }
+    compile('net.kyori:text-serializer-legacy:2.0.0') {
+        exclude(module: 'text-api')
+    }
     compileOnly 'com.google.code.gson:gson:2.7'
     compileOnly 'com.google.guava:guava:19.0'
 }
diff --git a/spark-common/src/main/java/me/lucko/spark/common/ActivityLog.java b/spark-common/src/main/java/me/lucko/spark/common/ActivityLog.java
new file mode 100644
index 0000000..4b5e942
--- /dev/null
+++ b/spark-common/src/main/java/me/lucko/spark/common/ActivityLog.java
@@ -0,0 +1,195 @@
+/*
+ * This file is part of spark.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package me.lucko.spark.common;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+import com.google.gson.JsonPrimitive;
+
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+
+public class ActivityLog {
+
+    private static final Gson GSON = new GsonBuilder().setPrettyPrinting().create();
+    private static final JsonParser PARSER = new JsonParser();
+
+    private final Path file;
+
+    private final List<Activity> log = new LinkedList<>();
+    private final Object[] mutex = new Object[0];
+
+    public ActivityLog(Path file) {
+        this.file = file;
+    }
+
+    public void addToLog(Activity activity) {
+        synchronized (this.mutex) {
+            this.log.add(activity);
+        }
+        save();
+    }
+
+    public List<Activity> getLog() {
+        synchronized (this.mutex) {
+            return new LinkedList<>(this.log);
+        }
+    }
+
+    public void save() {
+        JsonArray array = new JsonArray();
+        synchronized (this.mutex) {
+            for (Activity activity : this.log) {
+                if (!activity.shouldExpire()) {
+                    array.add(activity.serialize());
+                }
+            }
+        }
+
+        try {
+            Files.createDirectories(this.file.getParent());
+        } catch (IOException e) {
+            // ignore
+        }
+
+        try (BufferedWriter writer = Files.newBufferedWriter(this.file, StandardCharsets.UTF_8)) {
+            GSON.toJson(array, writer);
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public void load() {
+        if (!Files.exists(this.file)) {
+            synchronized (this.mutex) {
+                this.log.clear();
+                return;
+            }
+        }
+
+        JsonArray array;
+        try (BufferedReader reader = Files.newBufferedReader(this.file, StandardCharsets.UTF_8)) {
+            array = PARSER.parse(reader).getAsJsonArray();
+        } catch (IOException e) {
+            e.printStackTrace();
+            return;
+        }
+
+        boolean save = false;
+
+        synchronized (this.mutex) {
+            this.log.clear();
+            for (JsonElement element : array) {
+                try {
+                    Activity activity = Activity.deserialize(element);
+                    if (activity.shouldExpire()) {
+                        save = true;
+                    }
+                    this.log.add(activity);
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        if (save) {
+            try {
+                save();
+            } catch (Exception e) {
+                // ignore
+            }
+        }
+    }
+
+    public static final class Activity {
+        private final String user;
+        private final long time;
+        private final String type;
+        private final String url;
+
+        public Activity(String user, long time, String type, String url) {
+            this.user = user;
+            this.time = time;
+            this.type = type;
+            this.url = url;
+        }
+
+        public String getUser() {
+            return this.user;
+        }
+
+        public long getTime() {
+            return this.time;
+        }
+
+        public String getType() {
+            return this.type;
+        }
+
+        public String getUrl() {
+            return this.url;
+        }
+
+        public boolean shouldExpire() {
+            return (System.currentTimeMillis() - this.time) > TimeUnit.DAYS.toMillis(7);
+        }
+
+        public JsonObject serialize() {
+            JsonObject object = new JsonObject();
+
+            JsonObject user = new JsonObject();
+            user.add("name", new JsonPrimitive(this.user));
+            object.add("user", user);
+
+            object.add("time", new JsonPrimitive(this.time));
+            object.add("type", new JsonPrimitive(this.type));
+
+            JsonObject data = new JsonObject();
+            data.add("url", new JsonPrimitive(this.url));
+            object.add("data", data);
+
+            return object;
+        }
+
+        public static Activity deserialize(JsonElement element) {
+            JsonObject object = element.getAsJsonObject();
+
+            String user = object.get("user").getAsJsonObject().get("name").getAsJsonPrimitive().getAsString();
+            long time = object.get("time").getAsJsonPrimitive().getAsLong();
+            String type = object.get("type").getAsJsonPrimitive().getAsString();
+            String url = object.get("data").getAsJsonObject().get("url").getAsJsonPrimitive().getAsString();
+
+            return new Activity(user, time, type, url);
+        }
+    }
+
+}
diff --git a/spark-common/src/main/java/me/lucko/spark/common/CommandSender.java b/spark-common/src/main/java/me/lucko/spark/common/CommandSender.java
new file mode 100644
index 0000000..9d2ecc0
--- /dev/null
+++ b/spark-common/src/main/java/me/lucko/spark/common/CommandSender.java
@@ -0,0 +1,33 @@
+/*
+ * This file is part of spark.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package me.lucko.spark.common;
+
+import net.kyori.text.Component;
+
+public interface CommandSender {
+
+    String getName();
+
+    void sendMessage(Component message);
+
+    boolean hasPermission(String permission);
+
+}
diff --git a/spark-common/src/main/java/me/lucko/spark/common/SparkPlatform.java b/spark-common/src/main/java/me/lucko/spark/common/SparkPlatform.java
index 6b3eb21..d05d9e8 100644
--- a/spark-common/src/main/java/me/lucko/spark/common/SparkPlatform.java
+++ b/spark-common/src/main/java/me/lucko/spark/common/SparkPlatform.java
@@ -24,6 +24,7 @@ import com.google.common.collect.ImmutableList;
 import me.lucko.spark.common.command.Arguments;
 import me.lucko.spark.common.command.Command;
 import me.lucko.spark.common.command.CommandResponseHandler;
+import me.lucko.spark.common.command.modules.ActivityLogModule;
 import me.lucko.spark.common.command.modules.HealthModule;
 import me.lucko.spark.common.command.modules.MemoryModule;
 import me.lucko.spark.common.command.modules.SamplerModule;
@@ -35,6 +36,7 @@ import me.lucko.spark.common.sampler.TickCounter;
 import me.lucko.spark.common.util.BytebinClient;
 import net.kyori.text.Component;
 import net.kyori.text.TextComponent;
+import net.kyori.text.event.ClickEvent;
 import net.kyori.text.format.TextColor;
 import net.kyori.text.format.TextDecoration;
 import okhttp3.OkHttpClient;
@@ -47,10 +49,8 @@ import java.util.stream.Collectors;
 
 /**
  * Abstract spark implementation used by all platforms.
- *
- * @param <S> the sender (e.g. CommandSender) type used by the platform
  */
-public class SparkPlatform<S> {
+public class SparkPlatform {
 
     /** The URL of the viewer frontend */
     public static final String VIEWER_URL = "https://sparkprofiler.github.io/#";
@@ -59,22 +59,26 @@ public class SparkPlatform<S> {
     /** The bytebin instance used by the platform */
     public static final BytebinClient BYTEBIN_CLIENT = new BytebinClient(OK_HTTP_CLIENT, "https://bytebin.lucko.me/", "spark-plugin");
 
-    private final List<Command<S>> commands;
-    private final SparkPlugin<S> plugin;
-
+    private final SparkPlugin plugin;
+    private final List<Command> commands;
+    private final ActivityLog activityLog;
     private final TickCounter tickCounter;
     private final TpsCalculator tpsCalculator;
 
-    public SparkPlatform(SparkPlugin<S> plugin) {
+    public SparkPlatform(SparkPlugin plugin) {
         this.plugin = plugin;
 
-        ImmutableList.Builder<Command<S>> commandsBuilder = ImmutableList.builder();
-        new SamplerModule<S>().registerCommands(commandsBuilder::add);
-        new HealthModule<S>().registerCommands(commandsBuilder::add);
-        new TickMonitoringModule<S>().registerCommands(commandsBuilder::add);
-        new MemoryModule<S>().registerCommands(commandsBuilder::add);
+        ImmutableList.Builder<Command> commandsBuilder = ImmutableList.builder();
+        new SamplerModule().registerCommands(commandsBuilder::add);
+        new HealthModule().registerCommands(commandsBuilder::add);
+        new TickMonitoringModule().registerCommands(commandsBuilder::add);
+        new MemoryModule().registerCommands(commandsBuilder::add);
+        new ActivityLogModule().registerCommands(commandsBuilder::add);
         this.commands = commandsBuilder.build();
 
+        this.activityLog = new ActivityLog(plugin.getPluginFolder().resolve("activity.json"));
+        this.activityLog.load();
+
         this.tickCounter = plugin.createTickCounter();
         this.tpsCalculator = this.tickCounter != null ? new TpsCalculator() : null;
     }
@@ -92,10 +96,14 @@ public class SparkPlatform<S> {
         }
     }
 
-    public SparkPlugin<S> getPlugin() {
+    public SparkPlugin getPlugin() {
         return this.plugin;
     }
 
+    public ActivityLog getActivityLog() {
+        return this.activityLog;
+    }
+
     public TickCounter getTickCounter() {
         return this.tickCounter;
     }
@@ -104,17 +112,39 @@ public class SparkPlatform<S> {
         return this.tpsCalculator;
     }
 
-    public void executeCommand(S sender, String[] args) {
-        CommandResponseHandler<S> resp = new CommandResponseHandler<>(this, sender);
+    public void executeCommand(CommandSender sender, String[] args) {
+        CommandResponseHandler resp = new CommandResponseHandler(this, sender);
+
+        if (!sender.hasPermission("spark")) {
+            resp.replyPrefixed(TextComponent.of("You do not have permission to use this command.", TextColor.RED));
+            return;
+        }
+
         if (args.length == 0) {
-            sendUsage(resp);
+            resp.replyPrefixed(TextComponent.builder("")
+                    .append(TextComponent.of("spark", TextColor.WHITE))
+                    .append(Component.space())
+                    .append(TextComponent.of("v" + getPlugin().getVersion(), TextColor.GRAY))
+                    .build()
+            );
+            resp.replyPrefixed(TextComponent.builder("