did something

src/main/java/de/lunarakai/blockfox/commands/DeleteCommand.java

@@ -0,0 +1,4 @@
+package de.lunarakai.blockfox.commands;
+
+public class DeleteCommand {
+}

src/main/java/de/lunarakai/blockfox/common/BlockFoxDisplay.java

@@ -0,0 +1,55 @@
+package de.lunarakai.blockfox.common;
+
+import com.google.common.base.Preconditions;
+import de.lunarakai.blockfox.BlockFoxPlugin;
+import java.util.List;
+import java.util.UUID;
+import org.bukkit.Location;
+import org.bukkit.block.BlockFace;
+import org.bukkit.configuration.ConfigurationSection;
+import org.bukkit.entity.Player;
+
+public class BlockFoxDisplay {
+    private final BlockFoxPlugin plugin;
+    private final String name;
+    private final Location location;
+    private final Location centerLocation;
+    private final BlockFace orientation;
+    private DisplayStatus displayStatus = DisplayStatus.INACTIVE;
+    private BlockFoxDisplayMode blockFoxDisplayMode = BlockFoxDisplayMode.RSS_FEED;
+    private UUID[] textDisplays;
+    private Player currentPlayer;
+
+    public BlockFoxDisplay(BlockFoxPlugin plugin, ConfigurationSection displaySection) {
+        this.plugin = plugin;
+        this.name = Preconditions.checkNotNull(displaySection.getString("name"));
+        this.location = Preconditions.checkNotNull(displaySection.getLocation("location"));
+        this.textDisplays = new UUID[99]; // TODO
+
+        BlockFace orientation = BlockFace.NORTH;
+        try {
+            orientation = BlockFace.valueOf(displaySection.getString("orientation"));
+        } catch (IllegalArgumentException ignored) {
+
+        }
+        this.orientation = orientation;
+        this.centerLocation = location.clone().add(0.5, 0, 0.5);
+
+        String modeValue = displaySection.getString("mode");
+
+        switch(modeValue) {
+            case "fediverse": this.blockFoxDisplayMode = BlockFoxDisplayMode.FEDIVERSE_CLIENT; break;
+            default: this.blockFoxDisplayMode = BlockFoxDisplayMode.RSS_FEED;
+        }
+
+        List<String> list = displaySection.getStringList("textdisplays");
+        for(int i = 0; i < list.size(); i++) {
+            String textDisplay = list.get(i);
+            if(textDisplay != null) {
+                textDisplays[i] = UUID.fromString(textDisplay);
+            }
+        }
+    }
+
+
+}

src/main/java/de/lunarakai/blockfox/common/BlockFoxDisplayMode.java

@@ -0,0 +1,6 @@
+package de.lunarakai.blockfox.common;
+
+public enum BlockFoxDisplayMode {
+    RSS_FEED,
+    FEDIVERSE_CLIENT
+}

src/main/java/de/lunarakai/blockfox/common/DisplayList.java

@@ -1,4 +1,150 @@
 package de.lunarakai.blockfox.common;
 
+import de.lunarakai.blockfox.BlockFoxPlugin;
+import java.io.File;
+import java.io.IOException;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.UUID;
+import java.util.logging.Level;
+import org.bukkit.Location;
+import org.bukkit.block.Block;
+import org.bukkit.configuration.ConfigurationSection;
+import org.bukkit.configuration.InvalidConfigurationException;
+import org.bukkit.configuration.file.YamlConfiguration;
+import org.bukkit.entity.Player;
+
 public class DisplayList {
+    private static final String DISPLAY_LIST_FILENAME = "blockfox_displays.yml";
+    private final BlockFoxPlugin plugin;
+    private File displayListFile;
+
+    private final HashMap<String, BlockFoxDisplay> bfDisplays;
+    private final HashMap<UUID, BlockFoxDisplay> playerUsingBFDisplay;
+    private final HashMap<Location, BlockFoxDisplay> bfdisplayBlocks;
+    private final HashMap<UUID, BlockFoxDisplay> bfdisplayItemDisplays;
+    private final HashMap<BlockFoxDisplayMode, BlockFoxDisplay> bfDisplayMode;
+
+    public DisplayList(BlockFoxPlugin plugin) {
+        this.plugin = plugin;
+        this.bfDisplays = new HashMap<>();
+        this.bfdisplayBlocks = new HashMap<>();
+        this.playerUsingBFDisplay = new HashMap<>();
+        this.bfdisplayItemDisplays = new HashMap<>();
+        this.bfDisplayMode = new HashMap<>();
+        this.displayListFile = new File(plugin.getDataFolder(), DISPLAY_LIST_FILENAME);
+    }
+
+    public void load() {
+        bfDisplays.clear();
+        if(!this.displayListFile.exists()) {
+            return;
+        }
+
+        YamlConfiguration conf = new YamlConfiguration();
+        try {
+            conf.load(this.displayListFile);
+        } catch (IOException | InvalidConfigurationException e) {
+            plugin.getLogger().log(Level.SEVERE, "could not load display list file ", e);
+        }
+        ConfigurationSection displaysSection = conf.getConfigurationSection("displays");
+        if(displaysSection != null) {
+            for(String displayName : displaysSection.getKeys(false)) {
+                ConfigurationSection displaySection = displaysSection.getConfigurationSection(displayName);
+                if(displaySection != null) {
+                    BlockFoxDisplay blockFoxDisplay = new BlockFoxDisplay(plugin, displaySection);
+                    this.bfDisplays.put(blockFoxDisplay.getName(), blockFoxDisplay);
+                    setDisplayBlocks(blockFoxDisplay);
+                }
+            }
+        }
+    }
+
+    public void save() {
+        YamlConfiguration conf = new YamlConfiguration();
+        ConfigurationSection displaysSection = conf.createSection("displays");
+        int i = 0;
+        for(BlockFoxDisplay display : bfDisplays.values()) {
+            display.save(displaysSection.createSection(Integer.toString(i++)));
+        }
+        this.displayListFile.getParentFile().mkdirs();
+        try {
+            conf.save(this.displayListFile);
+        } catch (IOException e) {
+            plugin.getLogger().log(Level.SEVERE, "could not save display list file ", e);
+        }
+    }
+
+    private void setDisplayBlocks(BlockFoxDisplay blockFoxDisplay) {
+        for(Location loc : blockFoxDisplay.getBlocks()) {
+            bfdisplayBlocks.put(loc.clone(), blockFoxDisplay);
+        }
+        for(UUID uuid : blockFoxDisplay.getItemDisplays()) {
+            if(uuid != null) {
+                bfdisplayItemDisplays.put(uuid, blockFoxDisplay);
+            }
+        }
+    }
+
+    public BlockFoxDisplay getBlockFoxDisplay(String blockFoxDisplayName) {
+        return bfDisplays.get(blockFoxDisplayName);
+    }
+
+    public Collection<BlockFoxDisplay> getBlockFoxDisplays() {
+        return bfDisplays.values();
+    }
+
+    public void addBlockFoxDisplay(BlockFoxDisplay blockFoxDisplay) {
+        this.bfDisplays.put(blockFoxDisplay.getName(), blockFoxDisplay);
+        setDisplayBlocks(blockFoxDisplay);
+        save();
+    }
+
+    public boolean collidesWithBlockFoxDisplay(BlockFoxDisplay newBlockFoxDisplay) {
+        for(Location location : newBlockFoxDisplay.getBlocks()) {
+            if(bfdisplayBlocks.get(location) != null) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    public void setBlockFoxDisplayForPlayer(Player player, BlockFoxDisplay blockFoxDisplay) {
+        if(blockFoxDisplay != null) {
+            playerUsingBFDisplay.put(player.getUniqueId(), blockFoxDisplay);
+        } else {
+            playerUsingBFDisplay.remove(player.getUniqueId());
+        }
+    }
+
+    public BlockFoxDisplay getPlayerDisplay(Player player) {
+        return playerUsingBFDisplay.get(player.getUniqueId());
+    }
+
+    public BlockFoxDisplay getBFDisplayAtBlock(Block block) {
+        return bfdisplayBlocks.get(block.getLocation());
+    }
+
+    public BlockFoxDisplay getDisplayForItemDisplay(UUID id) {
+        return bfdisplayItemDisplays.get(id);
+    }
+
+    public void removeBlockFoxDisplay(BlockFoxDisplay blockFoxDisplay) {
+        if(blockFoxDisplay.hasPlayer()) {
+            plugin.getManager().quitDisplay(blockFoxDisplay.getCurrentPlayer(), true, true);
+        }
+
+        for(UUID uuid : arena.getItemDisplays()) {
+            if(uuid != null) {
+                bfdisplayItemDisplays.remove(uuid);
+            }
+        }
+        for(Location block : blockFoxDisplay.getBlocks()) {
+            bfdisplayBlocks.remove(block);
+        }
+        blockFoxDisplay.removeItemDisplay();
+
+        bfDisplays.remove(blockFoxDisplay.getName());
+        save();
+    }
 }