Support native playback on Windows (#360)

* Support native playback on Windows

* Use mypy-blessed platform switching logic

* Address feedback

* I think mypy is happy now

* Don't print srt when filename is None

* Fix ctypes imports

* Fix pylint and black complaints

Signed-off-by: rany <rany2@riseup.net>

* Have play_mp3_win32 use a guard clause to reduce nesting

Signed-off-by: rany <rany2@riseup.net>

---------

Signed-off-by: rany <rany2@riseup.net>
Co-authored-by: rany <rany2@riseup.net>

README.md

@@ -24,7 +24,7 @@ If you wish to play it back immediately with subtitles, you could use the `edge-
 
     $ edge-playback --text "Hello, world!"
 
-Note that `edge-playback` requires the installation of the [`mpv` command line player](https://mpv.io/).
+Note that `edge-playback` requires the installation of the [`mpv` command line player](https://mpv.io/), except on Windows.
 
 All `edge-tts` commands work with `edge-playback` with the exception of the `--write-media`, `--write-subtitles` and `--list-voices` options.
 

src/edge_playback/__init__.py

@@ -1,5 +1,6 @@
 """The edge_playback package wraps the functionality of mpv and edge-tts to generate
-text-to-speech (TTS) using edge-tts and then plays back the generated audio using mpv."""
+text-to-speech (TTS) using edge-tts and then plays back the generated audio using mpv.
+"""
 
 from .__main__ import _main
 

src/edge_playback/__main__.py

@@ -1,20 +1,37 @@
 """Main entrypoint for the edge-playback package."""
 
+import argparse
 import os
 import subprocess
 import sys
 import tempfile
 from shutil import which
 
-
-def pr_err(msg: str) -> None:
-    """Print to stderr."""
-    print(msg, file=sys.stderr)
+from .util import pr_err
 
 
 def _main() -> None:
     depcheck_failed = False
-    for dep in ("edge-tts", "mpv"):
+
+    parser = argparse.ArgumentParser(
+        prog="edge-playback",
+        description="Speak text using Microsoft Edge's online text-to-speech API",
+        epilog="See `edge-tts` for additional arguments",
+    )
+    parser.add_argument(
+        "--mpv",
+        action="store_true",
+        help="Use mpv to play audio. By default, false on Windows and true on all other platforms",
+    )
+    args, tts_args = parser.parse_known_args()
+
+    use_mpv = sys.platform != "win32" or args.mpv
+
+    deps = ["edge-tts"]
+    if use_mpv:
+        deps.append("mpv")
+
+    for dep in deps:
         if not which(dep):
             pr_err(f"{dep} is not installed.")
             depcheck_failed = True
@@ -33,31 +50,36 @@ def _main() -> None:
             media.close()
             mp3_fname = media.name
 
-        if not srt_fname:
+        if not srt_fname and use_mpv:
             subtitle = tempfile.NamedTemporaryFile(suffix=".srt", delete=False)
             subtitle.close()
             srt_fname = subtitle.name
 
         print(f"Media file: {mp3_fname}")
-        print(f"Subtitle file: {srt_fname}\n")
-        with subprocess.Popen(
-            [
-                "edge-tts",
-                f"--write-media={mp3_fname}",
-                f"--write-subtitles={srt_fname}",
-            ]
-            + sys.argv[1:]
-        ) as process:
+        if srt_fname:
+            print(f"Subtitle file: {srt_fname}\n")
+
+        edge_tts_cmd = ["edge-tts", f"--write-media={mp3_fname}"]
+        if srt_fname:
+            edge_tts_cmd.append(f"--write-subtitles={srt_fname}")
+        edge_tts_cmd = edge_tts_cmd + tts_args
+        with subprocess.Popen(edge_tts_cmd) as process:
             process.communicate()
 
-        with subprocess.Popen(
-            [
-                "mpv",
-                f"--sub-file={srt_fname}",
-                mp3_fname,
-            ]
-        ) as process:
-            process.communicate()
+        if sys.platform == "win32" and not use_mpv:
+            # pylint: disable-next=import-outside-toplevel
+            from .win32_playback import play_mp3_win32
+
+            play_mp3_win32(mp3_fname)
+        else:
+            with subprocess.Popen(
+                [
+                    "mpv",
+                    f"--sub-file={srt_fname}",
+                    mp3_fname,
+                ]
+            ) as process:
+                process.communicate()
     finally:
         if keep:
             print(f"\nKeeping temporary files: {mp3_fname} and {srt_fname}")

src/edge_playback/util.py

@@ -0,0 +1,8 @@
+"""Utility functions for edge-playback"""
+
+import sys
+
+
+def pr_err(msg: str) -> None:
+    """Print to stderr."""
+    print(msg, file=sys.stderr)

src/edge_playback/win32_playback.py

@@ -0,0 +1,52 @@
+"""Functions to play audio on Windows using native win32 APIs"""
+
+import sys
+
+from .util import pr_err
+
+
+def play_mp3_win32(mp3_fname: str) -> None:
+    """Play mp3 file with given path using win32 API"""
+
+    if sys.platform != "win32":
+        raise NotImplementedError("Function only available on Windows")
+
+    # pylint: disable-next=import-outside-toplevel
+    from ctypes import create_unicode_buffer, windll, wintypes  # type: ignore
+
+    _get_short_path_name_w = windll.kernel32.GetShortPathNameW
+    _get_short_path_name_w.argtypes = [
+        wintypes.LPCWSTR,
+        wintypes.LPWSTR,
+        wintypes.DWORD,
+    ]
+    _get_short_path_name_w.restype = wintypes.DWORD
+
+    def get_short_path_name(long_name: str) -> str:
+        """
+        Gets the DOS-safe short path name of a given long path.
+        http://stackoverflow.com/a/23598461/200291
+        """
+        output_buf_size = 0
+        while True:
+            output_buf = create_unicode_buffer(output_buf_size)
+            needed = _get_short_path_name_w(long_name, output_buf, output_buf_size)
+            if output_buf_size >= needed:
+                return output_buf.value
+            output_buf_size = needed
+
+    mci_send_string_w = windll.winmm.mciSendStringW
+
+    def mci_send(msg: str) -> None:
+        """Send MCI command string"""
+        result = mci_send_string_w(msg, 0, 0, 0)
+        if result != 0:
+            pr_err(f"Error {result} in mciSendString {msg}. Exiting.")
+            sys.exit(1)
+
+    mp3_shortname = get_short_path_name(mp3_fname)
+
+    mci_send("Close All")
+    mci_send(f'Open "{mp3_shortname}" Type MPEGVideo Alias theMP3')
+    mci_send("Play theMP3 Wait")
+    mci_send("Close theMP3")