WIP: Initial support for MacOS/`NSSpeechSynthesizer`.

* Add necessary dependencies, build script, and `NSSpeechSynthesizer` backend.
* Get very basic speech working.

Needs a delegate to handle queued speech, and currently segfaults if one is set.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tts"
-version = "0.3.9"
+version = "0.4.0"
 authors = ["Nolan Darilek <nolan@thewordnerd.info>"]
 repository = "https://github.com/ndarilek/tts-rs"
 description = "High-level Text-To-Speech (TTS) interface"
@@ -23,6 +23,10 @@ tts_winrt_bindings = { version = "0.1", path="winrt_bindings" }
 [target.'cfg(target_os = "linux")'.dependencies]
 speech-dispatcher = "0.4"
 
+[target.'cfg(target_os = "macos")'.dependencies]
+cocoa-foundation = "0.1"
+objc = "0.2"
+
 [target.wasm32-unknown-unknown.dependencies]
 wasm-bindgen = "0.2"
 web-sys = { version = "0.3", features = ["SpeechSynthesis", "SpeechSynthesisUtterance", "Window", ] }

build.rs

@@ -0,0 +1,14 @@
+// Copyright 2013-2015 The Servo Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+fn main() {
+    if std::env::var("TARGET").unwrap().contains("-apple") {
+        println!("cargo:rustc-link-lib=framework=AppKit");
+    }
+}

src/backends/mod.rs

@@ -10,6 +10,9 @@ pub(crate) mod winrt;
 #[cfg(target_arch = "wasm32")]
 mod web;
 
+#[cfg(target_os = "macos")]
+mod ns_speech_synthesizer;
+
 #[cfg(target_os = "linux")]
 pub use self::speech_dispatcher::*;
 
@@ -18,3 +21,6 @@ pub use self::tolk::*;
 
 #[cfg(target_arch = "wasm32")]
 pub use self::web::*;
+
+#[cfg(target_os = "macos")]
+pub use self::ns_speech_synthesizer::*;

src/backends/ns_speech_synthesizer.rs

@@ -0,0 +1,128 @@
+#[cfg(target_os = "macos")]
+#[link(name = "AppKit", kind = "framework")]
+use cocoa_foundation::base::nil;
+use cocoa_foundation::foundation::NSString;
+use log::{info, trace};
+use objc::declare::ClassDecl;
+use objc::runtime::*;
+use objc::*;
+
+use crate::{Backend, Error, Features};
+
+pub struct NSSpeechSynthesizerBackend(*mut Object);
+
+impl NSSpeechSynthesizerBackend {
+    pub fn new() -> Self {
+        info!("Initializing NSSpeechSynthesizer backend");
+        let mut obj: *mut Object = unsafe { msg_send![class!(NSSpeechSynthesizer), alloc] };
+        obj = unsafe { msg_send![obj, init] };
+        let mut decl = ClassDecl::new("MyNSSpeechSynthesizerDelegate", class!(NSObject)).unwrap();
+        extern "C" fn speech_synthesizer_did_finish_speaking(_: &Object, _: Sel, _: BOOL) {
+            println!("Got it");
+        }
+        unsafe {
+            decl.add_method(
+                sel!(didFinishSpeaking:),
+                speech_synthesizer_did_finish_speaking as extern "C" fn(&Object, Sel, BOOL) -> (),
+            )
+        };
+        let delegate_class = decl.register();
+        let delegate_object: Object = unsafe { msg_send![delegate_class, alloc] };
+        let _: () = unsafe { msg_send![obj, setDelegate: delegate_object] };
+        NSSpeechSynthesizerBackend(obj)
+    }
+}
+
+impl Backend for NSSpeechSynthesizerBackend {
+    fn supported_features(&self) -> Features {
+        Features {
+            stop: false,
+            rate: false,
+            pitch: false,
+            volume: false,
+            is_speaking: false,
+        }
+    }
+
+    fn speak(&mut self, text: &str, interrupt: bool) -> Result<(), Error> {
+        println!("speak({}, {})", text, interrupt);
+        let str = unsafe { NSString::alloc(nil).init_str(text) };
+        let success: BOOL = unsafe { msg_send![self.0, startSpeakingString: str] };
+        println!("Comparing");
+        if success == NO {
+            println!("Failed");
+            Ok(())
+        } else {
+            Ok(())
+        }
+    }
+
+    fn stop(&mut self) -> Result<(), Error> {
+        trace!("stop()");
+        unimplemented!()
+    }
+
+    fn min_rate(&self) -> f32 {
+        -100.
+    }
+
+    fn max_rate(&self) -> f32 {
+        100.
+    }
+
+    fn normal_rate(&self) -> f32 {
+        0.
+    }
+
+    fn get_rate(&self) -> Result<f32, Error> {
+        unimplemented!()
+    }
+
+    fn set_rate(&mut self, rate: f32) -> Result<(), Error> {
+        unimplemented!()
+    }
+
+    fn min_pitch(&self) -> f32 {
+        -100.
+    }
+
+    fn max_pitch(&self) -> f32 {
+        100.
+    }
+
+    fn normal_pitch(&self) -> f32 {
+        0.
+    }
+
+    fn get_pitch(&self) -> Result<f32, Error> {
+        unimplemented!()
+    }
+
+    fn set_pitch(&mut self, pitch: f32) -> Result<(), Error> {
+        unimplemented!()
+    }
+
+    fn min_volume(&self) -> f32 {
+        -100.
+    }
+
+    fn max_volume(&self) -> f32 {
+        100.
+    }
+
+    fn normal_volume(&self) -> f32 {
+        0.
+    }
+
+    fn get_volume(&self) -> Result<f32, Error> {
+        unimplemented!()
+    }
+
+    fn set_volume(&mut self, volume: f32) -> Result<(), Error> {
+        unimplemented!()
+    }
+
+    fn is_speaking(&self) -> Result<bool, Error> {
+        unimplemented!()
+    }
+}

src/lib.rs

@@ -21,6 +21,8 @@ pub enum Backends {
     Tolk,
     #[cfg(windows)]
     WinRT,
+    #[cfg(target_os = "macos")]
+    NSSpeechSynthesizer,
 }
 
 pub struct Features {
@@ -104,6 +106,10 @@ impl TTS {
                 let tts = backends::winrt::WinRT::new()?;
                 Ok(TTS(Box::new(tts)))
             }
+            #[cfg(target_os = "macos")]
+            Backends::NSSpeechSynthesizer => {
+                Ok(TTS(Box::new(backends::NSSpeechSynthesizerBackend::new())))
+            }
         }
     }
 
@@ -118,6 +124,8 @@ impl TTS {
         };
         #[cfg(target_arch = "wasm32")]
         let tts = TTS::new(Backends::Web);
+        #[cfg(target_os = "macos")]
+        let tts = TTS::new(Backends::NSSpeechSynthesizer);
         tts
     }