From 1f9b074d804d0c89c1d288718931978ae4617e8b Mon Sep 17 00:00:00 2001
From: Micah Johnston <micahrjohnston@gmail.com>
Date: Tue, 26 Mar 2024 11:29:23 -0500
Subject: [PATCH] param edit gesture API

---
 src/format/clap/host.rs      |  9 +++++--
 src/format/clap/instance.rs  |  3 ++-
 src/format/vst3/component.rs |  3 ++-
 src/format/vst3/host.rs      |  9 +++++--
 src/host.rs                  | 46 ++++++++++++++++++++++++++++++++++++
 src/lib.rs                   |  1 +
 src/plugin.rs                | 15 +-----------
 7 files changed, 66 insertions(+), 20 deletions(-)
 create mode 100644 src/host.rs

diff --git a/src/format/clap/host.rs b/src/format/clap/host.rs
index 59970ab..bb440c7 100644
--- a/src/format/clap/host.rs
+++ b/src/format/clap/host.rs
@@ -1,5 +1,10 @@
-use crate::plugin::HostInner;
+use crate::host::HostInner;
+use crate::params::{ParamId, ParamValue};
 
 pub struct ClapHost {}
 
-impl HostInner for ClapHost {}
+impl HostInner for ClapHost {
+    fn begin_gesture(&self, id: ParamId) {}
+    fn end_gesture(&self, id: ParamId) {}
+    fn set_param(&self, id: ParamId, value: ParamValue) {}
+}
diff --git a/src/format/clap/instance.rs b/src/format/clap/instance.rs
index fe36a83..4443017 100644
--- a/src/format/clap/instance.rs
+++ b/src/format/clap/instance.rs
@@ -14,8 +14,9 @@ use crate::buffers::{BufferData, BufferType, Buffers};
 use crate::bus::{BusDir, Format};
 use crate::editor::Editor;
 use crate::events::{Data, Event, Events};
+use crate::host::Host;
 use crate::params::{ParamId, ParamInfo, ParamValue};
-use crate::plugin::{Host, Plugin, PluginInfo};
+use crate::plugin::{Plugin, PluginInfo};
 use crate::process::{Config, Processor};
 use crate::sync::params::ParamValues;
 use crate::util::{copy_cstring, slice_from_raw_parts_checked, DisplayParam};
diff --git a/src/format/vst3/component.rs b/src/format/vst3/component.rs
index 0255e14..2640159 100644
--- a/src/format/vst3/component.rs
+++ b/src/format/vst3/component.rs
@@ -13,8 +13,9 @@ use super::view::View;
 use crate::bus::{BusDir, Format, Layout};
 use crate::editor::Editor;
 use crate::events::{Data, Event, Events};
+use crate::host::Host;
 use crate::params::ParamId;
-use crate::plugin::{Host, Plugin, PluginInfo};
+use crate::plugin::{Plugin, PluginInfo};
 use crate::process::{Config, Processor};
 use crate::sync::params::ParamValues;
 use crate::util::{slice_from_raw_parts_checked, DisplayParam};
diff --git a/src/format/vst3/host.rs b/src/format/vst3/host.rs
index 3a18d95..b93a5ed 100644
--- a/src/format/vst3/host.rs
+++ b/src/format/vst3/host.rs
@@ -1,5 +1,10 @@
-use crate::plugin::HostInner;
+use crate::host::HostInner;
+use crate::params::{ParamId, ParamValue};
 
 pub struct Vst3Host {}
 
-impl HostInner for Vst3Host {}
+impl HostInner for Vst3Host {
+    fn begin_gesture(&self, id: ParamId) {}
+    fn end_gesture(&self, id: ParamId) {}
+    fn set_param(&self, id: ParamId, value: ParamValue) {}
+}
diff --git a/src/host.rs b/src/host.rs
new file mode 100644
index 0000000..bc396b1
--- /dev/null
+++ b/src/host.rs
@@ -0,0 +1,46 @@
+use std::sync::Arc;
+
+use crate::params::{ParamId, ParamInfo, ParamValue};
+
+pub trait HostInner {
+    fn begin_gesture(&self, id: ParamId);
+    fn end_gesture(&self, id: ParamId);
+    fn set_param(&self, id: ParamId, value: ParamValue);
+}
+
+#[derive(Clone)]
+pub struct Host {
+    inner: Arc<dyn HostInner + Send + Sync>,
+}
+
+impl Host {
+    pub fn from_inner(inner: Arc<dyn HostInner + Send + Sync>) -> Host {
+        Host { inner }
+    }
+
+    pub fn edit_param(&self, id: ParamId) -> Gesture {
+        self.inner.begin_gesture(id);
+
+        Gesture {
+            inner: Arc::clone(&self.inner),
+            id,
+        }
+    }
+}
+
+pub struct Gesture {
+    inner: Arc<dyn HostInner + Send + Sync>,
+    id: ParamId,
+}
+
+impl Gesture {
+    pub fn set_value(&self, value: ParamValue) {
+        self.inner.set_param(self.id, value);
+    }
+}
+
+impl Drop for Gesture {
+    fn drop(&mut self) {
+        self.inner.end_gesture(self.id);
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index 0a78e5e..dc9583d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -3,6 +3,7 @@ pub mod bus;
 pub mod editor;
 pub mod events;
 pub mod format;
+pub mod host;
 pub mod params;
 pub mod plugin;
 pub mod process;
diff --git a/src/plugin.rs b/src/plugin.rs
index 363b7f6..8a346fe 100644
--- a/src/plugin.rs
+++ b/src/plugin.rs
@@ -1,8 +1,8 @@
 use std::io::{self, Read, Write};
-use std::sync::Arc;
 
 use crate::bus::{BusInfo, Layout};
 use crate::editor::{Editor, Parent};
+use crate::host::Host;
 use crate::params::{ParamId, ParamInfo, ParamValue};
 use crate::process::{Config, Processor};
 
@@ -34,19 +34,6 @@ impl Default for PluginInfo {
     }
 }
 
-pub trait HostInner {}
-
-#[derive(Clone)]
-pub struct Host {
-    _inner: Arc<dyn HostInner>,
-}
-
-impl Host {
-    pub fn from_inner(inner: Arc<dyn HostInner>) -> Host {
-        Host { _inner: inner }
-    }
-}
-
 pub trait Plugin: Send + Sized + 'static {
     type Processor: Processor;
     type Editor: Editor;