1 files changed, 231 insertions, 0 deletions
diff --git a/backends/common.py b/backends/common.py
new file mode 100644
index 0000000..2c6437f
--- /dev/null
+++ b/backends/common.py
@@ -0,0 +1,231 @@
+"""Shared helpers for the backend setup wizards.
+
+Every TTS backend setup wizard (audio.cpp, qwen, faster) lives in its own
+module under ``backends``; this module holds the pieces more than one of
+them needs: .wav discovery, path normalization, and the regex edit that
+keeps ``converter/config.py`` in sync with the choices made in a wizard.
+It deliberately imports nothing from the other backend modules (or the
+TUI) so it can be reused without pulling curses into a non-interactive
+run.
+"""
+
+import os
+import re
+import urllib.parse
+from pathlib import Path
+from typing import Dict, List, Optional, Set, Tuple
+
+# The tts-audiobook-generator checkout root (where audiobook.py lives).
+# Backend checkouts are cloned into subdirectories of this root
+# (./audio.cpp, ./faster-qwen3-tts) so a single tree holds everything.
+TTS_ROOT = Path(__file__).resolve().parent.parent
+
+# converter/config.py — rewritten in place by update_config_value so the
+# converter picks up the host/port/voice a wizard configured.
+CONFIG_PATH = TTS_ROOT / "converter" / "config.py"
+
+# Output directory of tts-audiobook-generator; never offered as a .wav
+# source by detect_wav_dir.
+TTS_OUTPUT_DIR = "output"
+
+# The voice-transcript mapping file audio.cpp reads from its voice_dir.
+# (The faster backend uses voices.json instead; see backends.faster.)
+PROMPT_TEXT_FILENAME = "prompt_text"
+
+
+def normalize_dir_arg(value: str) -> Path:
+    """Normalize a user-supplied path argument.
+
+    Strips surrounding quotes (a common copy-paste artifact), expands a
+    leading ``~``, and resolves the result to an absolute path so relative
+    paths are always validated against the current working directory.
+    """
+    cleaned = value.strip()
+    if len(cleaned) >= 2 and cleaned[0] == cleaned[-1] and cleaned[0] in "\"'":
+        cleaned = cleaned[1:-1]
+    return Path(os.path.expanduser(cleaned)).resolve()
+
+
+def resolve_wav_dir_arg(value: str) -> Path:
+    """Normalize a user-supplied wav directory argument."""
+    return normalize_dir_arg(value)
+
+
+def find_wav_files(input_dir: Path) -> List[Path]:
+    """Return the .wav files in INPUT_DIR, sorted alphabetically by name."""
+    return sorted(
+        (path for path in input_dir.iterdir()
+         if path.is_file() and path.suffix.lower() == ".wav"),
+        key=lambda path: path.name.lower(),
+    )
+
+
+def count_wavs(directory: Path) -> int:
+    """Count the .wav files in DIRECTORY (0 when it cannot be read)."""
+    try:
+        return sum(1 for path in directory.iterdir()
+                   if path.is_file() and path.suffix.lower() == ".wav")
+    except OSError:
+        return 0
+
+
+def detect_wav_dir(audiocpp_dir: Path, tts_root: Path) -> Optional[Path]:
+    """Find a unique directory that directly contains .wav files.
+
+    Looks shallowly (the root itself and its immediate subdirectories) in
+    both the audio.cpp checkout and the tts-audiobook-generator root (where
+    audiobook.py lives), since clone reference .wavs commonly live in
+    either. The tts-audiobook-generator ``output/`` directory is excluded.
+    When exactly one candidate is found it is returned (as a starting
+    directory for the .wav browser); when none or several are found None is
+    returned so the caller falls back to its default start location.
+    """
+    candidates: List[Path] = []
+    seen: Set[Path] = set()
+
+    def consider(directory: Path) -> None:
+        try:
+            resolved = directory.resolve()
+        except OSError:
+            return
+        if resolved in seen:
+            return
+        seen.add(resolved)
+        if count_wavs(directory) > 0:
+            candidates.append(directory)
+
+    for root in (audiocpp_dir, tts_root):
+        if not root.is_dir():
+            continue
+        consider(root)
+        try:
+            children = sorted(root.iterdir(), key=lambda p: p.name.lower())
+        except OSError:
+            continue
+        for child in children:
+            if not child.is_dir() or child.name.startswith("."):
+                continue
+            if root == tts_root and child.name == TTS_OUTPUT_DIR:
+                continue
+            consider(child)
+
+    if len(candidates) == 1:
+        return candidates[0]
+    return None
+
+
+def wav_dir_info(directory: Path) -> Tuple[str, str]:
+    """TUI status describing the directory listed in the wav browser."""
+    count = count_wavs(directory)
+    if count:
+        wavs = ".wav" if count == 1 else ".wavs"
+        return (f"{count} {wavs} found in this directory. Press Enter.",
+                "ok")
+    return ("No .wav files found in this directory", "warn")
+
+
+def wav_dir_preview(directory: Path) -> Tuple[str, str]:
+    """TUI status describing a highlighted subdirectory in the wav browser."""
+    count = count_wavs(directory)
+    if count:
+        wavs = ".wav" if count == 1 else ".wavs"
+        return (f"{count} {wavs}", "ok")
+    return ("no .wav files", "info")
+
+
+def url_with_port(url: str, port: int) -> str:
+    """Return URL with its port replaced/inserted as PORT."""
+    parts = urllib.parse.urlsplit(url)
+    host = parts.hostname or "127.0.0.1"
+    return urllib.parse.urlunsplit(
+        (parts.scheme or "http", f"{host}:{port}", parts.path, "", ""))
+
+
+def update_config_value(key: str, value: str,
+                        config_path: Optional[Path] = None) -> bool:
+    """Rewrite a ``KEY = "value"`` line in converter/config.py.
+
+    Only the quoted literal is replaced; surrounding lines and the trailing
+    comment are preserved. Returns True when the file was changed. Used by
+    the qwen and faster wizards to keep their API URL / voice / speaker
+    settings in sync with the converter.
+    """
+    path = Path(config_path) if config_path is not None else CONFIG_PATH
+    try:
+        text = path.read_text(encoding="utf-8")
+    except OSError:
+        return False
+    match = re.search(r'(?m)^(\s*' + re.escape(key) + r'\s*=\s*")([^"]*)(")',
+                      text)
+    if not match or match.group(2) == value:
+        return False
+    text = text[:match.start(2)] + value + text[match.end(2):]
+    try:
+        path.write_text(text, encoding="utf-8")
+    except OSError:
+        return False
+    return True
+
+
+def read_prompt_text(prompt_path: Path) -> Dict[str, str]:
+    """Parse a prompt_text file into a stem -> transcript mapping.
+
+    Lines are ``<name>|<transcript>``; blank lines are skipped and a line
+    without a ``|`` separator is treated as a name with an empty transcript.
+    Returns an empty mapping when the file does not exist.
+    """
+    if not prompt_path.exists():
+        return {}
+    mapping: Dict[str, str] = {}
+    for line in prompt_path.read_text(encoding="utf-8").splitlines():
+        if not line.strip():
+            continue
+        if "|" in line:
+            name, _, text = line.partition("|")
+        else:
+            name, text = line, ""
+        mapping[name.strip()] = text
+    return mapping
+
+
+def write_prompt_text(wav_dir: Path,
+                      transcripts: Dict[str, str]) -> Path:
+    """Write the voice_dir prompt_text mapping into WAV_DIR.
+
+    One ``<basename-without-extension>|<transcript>`` line per voice.
+    Returns the path of the written file.
+    """
+    prompt_path = wav_dir / PROMPT_TEXT_FILENAME
+    lines = [f"{name}|{text}" for name, text in transcripts.items()]
+    prompt_path.write_text("\n".join(lines) + "\n", encoding="utf-8")
+    return prompt_path
+
+
+def run_console_subprocess(argv: List[str], cwd: Optional[Path] = None) -> int:
+    """Run a subprocess whose output streams to the plain console.
+
+    Used inside ``tui.suspend`` for clone/build/pip steps: the caller has
+    already left curses mode, so the child inherits the real terminal and
+    its output appears normally. Returns the process exit code.
+    """
+    import subprocess
+    try:
+        result = subprocess.run(argv, cwd=str(cwd) if cwd is not None else None)
+    except OSError as exc:
+        print(f"[ERROR] Could not run {' '.join(argv)}: {exc}")
+        return 1
+    return result.returncode
+
+
+def git_clone(url: str, target: Path) -> int:
+    """Clone URL into TARGET, streaming to the console. Returns exit code."""
+    print(f"[INFO] Cloning {url} into {target}...")
+    return run_console_subprocess(["git", "clone", url, str(target)])
+
+
+def pip_install(packages: List[str]) -> int:
+    """pip install PACKAGES (into the current environment). Returns exit code."""
+    print(f"[INFO] pip install {' '.join(packages)}...")
+    import sys
+    return run_console_subprocess([sys.executable, "-m", "pip", "install",
+                                   *packages])