From d0ddaf0b581e083a1f615d6509f1af907a5ce82c Mon Sep 17 00:00:00 2001
From: Alexandros Theodotou <alex@zrythm.org>
Date: Thu, 23 Apr 2026 12:53:42 +0900
Subject: [PATCH] Add clap_host_preset_load support to Host base class

---
 include/clap/helpers/host.hh  | 24 ++++++++++++++++++++++++
 include/clap/helpers/host.hxx | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+)

diff --git a/include/clap/helpers/host.hh b/include/clap/helpers/host.hh
index 5d11332..21aef96 100644
--- a/include/clap/helpers/host.hh
+++ b/include/clap/helpers/host.hh
@@ -108,6 +108,17 @@ namespace clap { namespace helpers {
       virtual bool implementsThreadPool() const noexcept { return false; }
       virtual bool threadPoolRequestExec(uint32_t numTasks) noexcept { return false; }
 
+      // clap_host_preset_load
+      virtual bool implementsPresetLoad() const noexcept { return false; }
+      virtual void presetLoadLoaded(uint32_t locationKind,
+                                    const char *location,
+                                    const char *loadKey) noexcept {}
+      virtual void presetLoadOnError(uint32_t locationKind,
+                                     const char *location,
+                                     const char *loadKey,
+                                     int32_t osError,
+                                     const char *msg) noexcept {}
+
       // clap_host_surround
       virtual bool implementsSurround() const noexcept { return false; }
       virtual void surroundChanged() noexcept {}
@@ -197,6 +208,18 @@ namespace clap { namespace helpers {
       // clap_host_thread_pool
       static bool clapThreadPoolRequestExec(const clap_host *host, uint32_t num_tasks) noexcept;
 
+      // clap_host_preset_load
+      static void clapPresetLoadLoaded(const clap_host *host,
+                                       uint32_t location_kind,
+                                       const char *location,
+                                       const char *load_key) noexcept;
+      static void clapPresetLoadOnError(const clap_host *host,
+                                        uint32_t location_kind,
+                                        const char *location,
+                                        const char *load_key,
+                                        int32_t os_error,
+                                        const char *msg) noexcept;
+
       // clap_host_surround
       static void clapSurroundChanged(const clap_host_t *host) noexcept;
 
@@ -210,6 +233,7 @@ namespace clap { namespace helpers {
       static const clap_host_log _hostLog;
       static const clap_host_params _hostParams;
       static const clap_host_posix_fd_support _hostPosixFdSupport;
+      static const clap_host_preset_load _hostPresetLoad;
       static const clap_host_remote_controls _hostRemoteControls;
       static const clap_host_state _hostState;
       static const clap_host_timer_support _hostTimerSupport;
diff --git a/include/clap/helpers/host.hxx b/include/clap/helpers/host.hxx
index e1bd0fa..e8e0508 100644
--- a/include/clap/helpers/host.hxx
+++ b/include/clap/helpers/host.hxx
@@ -48,6 +48,12 @@ namespace clap { namespace helpers {
       clapPosixFdSupportUnregisterFd,
    };
 
+   template <MisbehaviourHandler h, CheckingLevel l>
+   const clap_host_preset_load Host<h, l>::_hostPresetLoad = {
+      clapPresetLoadOnError,
+      clapPresetLoadLoaded,
+   };
+
    template <MisbehaviourHandler h, CheckingLevel l>
    const clap_host_remote_controls Host<h, l>::_hostRemoteControls = {
       clapRemoteControlsChanged,
@@ -156,6 +162,10 @@ namespace clap { namespace helpers {
          return &_hostParams;
       if (!strcmp(extension_id, CLAP_EXT_POSIX_FD_SUPPORT) && self.implementsPosixFdSupport())
          return &_hostPosixFdSupport;
+      if ((!strcmp(extension_id, CLAP_EXT_PRESET_LOAD) ||
+           !strcmp(extension_id, CLAP_EXT_PRESET_LOAD_COMPAT)) &&
+          self.implementsPresetLoad())
+         return &_hostPresetLoad;
       if ((!strcmp(extension_id, CLAP_EXT_REMOTE_CONTROLS) ||
            !strcmp(extension_id, CLAP_EXT_REMOTE_CONTROLS_COMPAT)) &&
           self.implementsRemoteControls())
@@ -329,6 +339,31 @@ namespace clap { namespace helpers {
       return self.posixFdSupportUnregisterFd(fd);
    }
 
+   //-------------------------//
+   // clap_host_preset_load //
+   //-------------------------//
+   template <MisbehaviourHandler h, CheckingLevel l>
+   void Host<h, l>::clapPresetLoadLoaded(const clap_host *host,
+                                          uint32_t location_kind,
+                                          const char *location,
+                                          const char *load_key) noexcept {
+      auto &self = from(host);
+      self.ensureMainThread("preset_load.loaded");
+      self.presetLoadLoaded(location_kind, location, load_key);
+   }
+
+   template <MisbehaviourHandler h, CheckingLevel l>
+   void Host<h, l>::clapPresetLoadOnError(const clap_host *host,
+                                           uint32_t location_kind,
+                                           const char *location,
+                                           const char *load_key,
+                                           int32_t os_error,
+                                           const char *msg) noexcept {
+      auto &self = from(host);
+      self.ensureMainThread("preset_load.on_error");
+      self.presetLoadOnError(location_kind, location, load_key, os_error, msg);
+   }
+
    //---------------------------//
    // clap_host_remote_controls //
    //---------------------------//