Added

• Folia support - the plugin now runs on Folia (marked folia-supported: true in plugin.yml). Folia's GlobalRegionScheduler is used automatically when detected at runtime; Paper/Spigot continue to use the Bukkit scheduler.
• compat/ package hierarchy - clean OOP abstraction layer:
  • compat.platform.PlatformDetector - detects Folia vs. Paper/Spigot at startup via RegionizedServer class presence.
  • compat.scheduler.SchedulerAdapter / TaskHandle - platform-agnostic scheduler interface (runTask, runTaskTimer, runTaskLater, runTaskAsync).
  • compat.scheduler.BukkitSchedulerAdapter - SchedulerAdapter backed by BukkitScheduler (Paper/Spigot).
  • compat.scheduler.FoliaSchedulerAdapter - SchedulerAdapter backed by GlobalRegionScheduler (Folia); only class-loaded when Folia is detected.
  • compat.scheduler.SchedulerAdapterFactory - chooses the correct adapter with graceful fallback if Folia classes are missing.
  • compat.version.ServerVersionUtil - canonical location for runtime Minecraft version detection (replaces util.ServerVersionUtil).
  • compat.material.MaterialCompat - canonical location for cross-version material resolution (replaces util.MaterialCompat).
• Startup platform log - PluginBootstrap now logs the active scheduler adapter class on enable (e.g. Scheduler: BukkitSchedulerAdapter).

Changed

• util.ServerVersionUtil and util.MaterialCompat are now @Deprecated delegation stubs that forward to their canonical compat.* counterparts; they will be removed in a future release.

• All internal scheduler usages (CountdownManager, FireworkShowManager, PatternScheduler, ChatInputListener, all listener.actions.* GUI action classes, SpigotIntegration, SpigotUpdateChecker) now go through SchedulerAdapter instead of Bukkit.getScheduler() / BukkitRunnable directly.

• Scoreboard API modernised - ScoreboardDisplay now delegates to compat.scoreboard.ScoreboardCompat. On Paper 1.20.3+ (Criteria.DUMMY available) the modern registerNewObjective(String, Criteria, Component) overload is used; older builds fall back to the legacy string overload. The deprecated Scoreboard.resetScores(String) calls are replaced by objective unregister/re-register via ScoreboardCompat.resetObjective.

• Title API modernised - TitleDisplay now delegates to compat.title.TitleCompat. On Paper 1.18+ the Adventure Player.showTitle(Title) / Player.clearTitle() APIs are preferred over the deprecated sendTitle(String...) / resetTitle(). TitleValidator now also accepts showTitle as a valid title capability. A Spigot/legacy string fallback is retained.

• Per-player notification targeting - NotificationBuilder.players(Collection<Player>) restricts a notification to specific players. EzCountdownApi.sendNotification(Notification, Collection<Player>) provides an inline alternative without building a Notification first.

• Countdown.isVisibleTo(Player) - centralises per-player visibility logic (permission gate + target-player set) in one method; all display handlers now use it instead of duplicated inline checks.

• CountdownBuilder.targetPlayers(Collection<Player>) - restrict a persistent countdown's display to specific players.

• Developer-friendly exception hierarchy - new com.skyblockexp.ezcountdown.api.exception package:

  • EzCountdownException - base unchecked exception; catch this for all EzCountdown API errors.
  • CountdownNotFoundException - thrown when referencing a countdown name that does not exist; carries getCountdownName().
  • DuplicateCountdownException - thrown when creating a countdown whose name already exists; carries getCountdownName().
  • InvalidConfigurationException - thrown by NotificationBuilder.build() and future builder validators when configuration is invalid; replaces the generic IllegalStateException.

• api-version bumped to 1.18 in plugin.yml; minimum supported Minecraft version is Paper/Spigot 1.18. Dialog display continues to require Paper 1.21.7+.

• Broadened Java compatibility - release JARs now target Java 17 bytecode (previously Java 21), so the plugin runs on Paper 1.18 - 1.20.4 (Java 17) as well as Paper 1.20.5+ (Java 21). The jdk21 Maven profile also targets Java 17 bytecode.

• ServerVersionUtil - new utility class (com.skyblockexp.ezcountdown.util.ServerVersionUtil) for runtime Minecraft version detection; enables future conditional feature gating without hard API dependencies.

• Startup guard - onEnable now logs the detected MC and Java version and disables the plugin with a clear error message if the server is too old (MC < 1.18 or Java < 17).

Changed

• All display handlers (ActionBarDisplay, TitleDisplay, ChatDisplay, BossBarDisplay, ScoreboardDisplay, DialogDisplay) use countdown.isVisibleTo(player) instead of duplicated inline permission checks.
• NotificationBuilder.build() now throws InvalidConfigurationException (a subclass of EzCountdownException) instead of a plain IllegalStateException.
• ScoreboardDisplay catch blocks now include NoSuchMethodError so the scoreboard falls back to chat if the String-criteria registerNewObjective overload is ever removed in a future Paper build.
• Project version bumped from 1.4.3 to 2.0.0.

Fixed

• DURATION countdown resets to full duration on /countdown reload - resumeRunningCountdowns() previously called handler.onStart(), which always sets targetInstant to now + fullDuration, discarding the target_epoch saved in storage. It now calls handler.ensureTarget() instead, which is a no-op when a target is already present. The same guard was added to the legacy fallback path for handler-less countdown types. End-commands that fired once before a reload will no longer fire again unexpectedly due to the countdown silently restarting.