Changes to be committed:

new file:   AGENTS.md
	modified:   pyproject.toml
	modified:   src/epub_tts/__main__.py
	new file:   src/epub_tts/tts_backend.py

src/epub_tts/__main__.py

@@ -7,6 +7,15 @@
 import sys
 from argparse import ArgumentParser
 
+from epub_tts import tts_backend
+from epub_tts import tts_edge
+
+backend = {
+    # keys are the backend names, values are the corresponding TTS classes
+    "default": tts_backend.GenericTTSBackend,
+    "edge": tts_edge.TTSEdge,
+}
+
 
 def main(args=None):
     p = ArgumentParser(description="Convert EPUB to audio using TTS")
@@ -20,10 +29,15 @@ def main(args=None):
     p.add_argument("-o", "--output", help="Output audio file", required=True)
     p.add_argument("-l", "--language", help="Language to use for TTS")
     p.add_argument("-v", "--voice", help="Voice to use for TTS")
-
+    p.add_argument("-b", "--backend", 
+                   help="Backend to use for TTS",
+                   default="default",
+                   choices=backend.keys())
     args = p.parse_args(args or sys.argv[1:])
     print(
-        f"Converting {args.input} to {args.output} using voice {args.voice}, language {args.language}, ..."
+        f"Converting {args.input} to {args.output} using voice "
+        f"{args.voice}, language {args.language}, "
+        f"backend {args.backend}, ..."
     )