fix: resolve shell values in installer configs

install.py

@@ -39,6 +39,16 @@ RELEASE_URL = (
 )
 MAX_RETRIES = 3
 
+# Fallback BIOS destination per platform when --platform is forced
+# but auto-detection finds nothing on the machine.
+DEFAULT_DESTS = {
+    "batocera": Path("/userdata/bios"),
+    "recalbox": Path("/recalbox/share/bios"),
+    "lakka": Path("/storage/system"),
+    "retrodeck": Path.home() / "retrodeck",
+    "emudeck": Path.home() / "Emulation" / "bios",
+}
+
 
 def detect_os() -> str:
     """Return normalized OS identifier."""
@@ -98,8 +108,46 @@ def _parse_retroarch_system_dir(cfg_path: Path) -> Path | None:
     return None
 
 
+def _shell_unquote(value: str) -> str:
+    """Resolve a shell right-hand side into its effective string value.
+
+    Handles concatenated quoted/unquoted segments the way bash does
+    (e.g. "/run/media/deck/EmuSD"/Emulation), expands variables in
+    double-quoted and unquoted segments, and stops at unquoted
+    whitespace or a comment.
+    """
+    parts: list[str] = []
+    i = 0
+    n = len(value)
+    while i < n:
+        c = value[i]
+        if c == '"':
+            end = value.find('"', i + 1)
+            if end == -1:
+                parts.append(os.path.expandvars(value[i + 1:]))
+                break
+            parts.append(os.path.expandvars(value[i + 1:end]))
+            i = end + 1
+        elif c == "'":
+            end = value.find("'", i + 1)
+            if end == -1:
+                parts.append(value[i + 1:])
+                break
+            parts.append(value[i + 1:end])
+            i = end + 1
+        elif c.isspace() or c == "#":
+            break
+        else:
+            end = i
+            while end < n and value[end] not in "\"'#" and not value[end].isspace():
+                end += 1
+            parts.append(os.path.expandvars(value[i:end]))
+            i = end
+    return os.path.expanduser("".join(parts))
+
+
 def _parse_bash_var(path: Path, key: str) -> str | None:
-    """Extract value of key= from a bash/shell file."""
+    """Extract the effective value of key= from a bash/shell file."""
     if not path.exists():
         return None
     try:
@@ -107,12 +155,25 @@ def _parse_bash_var(path: Path, key: str) -> str | None:
             line = line.strip()
             if line.startswith(f"{key}="):
                 _, _, value = line.partition("=")
-                return value.strip('"').strip("'")
+                return _shell_unquote(value)
     except OSError:
         pass
     return None
 
 
+def _parse_json_path(path: Path, *keys: str) -> str | None:
+    """Extract a nested string value from a JSON file."""
+    if not path.exists():
+        return None
+    try:
+        data = json.loads(path.read_text(encoding="utf-8", errors="replace"))
+        for key in keys:
+            data = data[key]
+        return data if isinstance(data, str) and data else None
+    except (OSError, json.JSONDecodeError, KeyError, TypeError):
+        return None
+
+
 def _parse_ps1_var(path: Path, key: str) -> str | None:
     """Extract value of $key= or key= from a PowerShell file."""
     if not path.exists():
@@ -152,7 +213,10 @@ def _detect_embedded() -> list[tuple[str, Path]]:
         found.append(("batocera", Path("/userdata/bios")))
         return found
 
-    if Path("/usr/bin/recalbox-settings").exists():
+    if (
+        Path("/recalbox/recalbox.version").exists()
+        or Path("/usr/bin/recalbox-settings").exists()
+    ):
         found.append(("recalbox", Path("/recalbox/share/bios")))
         return found
 
@@ -187,14 +251,17 @@ def detect_platforms(os_type: str) -> list[tuple[str, Path]]:
                 bios_dir = Path(emu_path) / "bios"
                 found.append(("emudeck", bios_dir))
 
-        # RetroDECK
-        retrodeck_cfg = home / ".var" / "app" / "net.retrodeck.retrodeck" / "config" / "retrodeck" / "retrodeck.cfg"
-        if retrodeck_cfg.exists():
-            bios_path = _parse_bash_var(retrodeck_cfg, "rdhome")
-            if bios_path:
-                found.append(("retrodeck", Path(bios_path)))
-            else:
-                found.append(("retrodeck", home / "retrodeck"))
+        # RetroDECK: retrodeck.json since the cfg-to-json migration, which
+        # renames the old retrodeck.cfg to retrodeck.bak (global.sh:149-153)
+        retrodeck_conf_dir = home / ".var" / "app" / "net.retrodeck.retrodeck" / "config" / "retrodeck"
+        retrodeck_json = retrodeck_conf_dir / "retrodeck.json"
+        retrodeck_cfg = retrodeck_conf_dir / "retrodeck.cfg"
+        if retrodeck_json.exists():
+            rd_home = _parse_json_path(retrodeck_json, "paths", "rd_home_path")
+            found.append(("retrodeck", Path(rd_home) if rd_home else home / "retrodeck"))
+        elif retrodeck_cfg.exists():
+            rd_home = _parse_bash_var(retrodeck_cfg, "rdhome")
+            found.append(("retrodeck", Path(rd_home) if rd_home else home / "retrodeck"))
 
         # RetroArch Flatpak
         flatpak_cfg = home / ".var" / "app" / "org.libretro.RetroArch" / "config" / "retroarch" / "retroarch.cfg"
@@ -572,8 +639,12 @@ def main() -> None:
         if matched:
             platforms = matched
         else:
-            print(f"  Platform '{args.platform}' not detected, using default path.")
-            platforms = [(args.platform, Path.home() / "bios")]
+            default_dest = DEFAULT_DESTS.get(args.platform, Path.home() / "bios")
+            print(
+                f"  Platform '{args.platform}' not detected, "
+                f"using default path: {default_dest}"
+            )
+            platforms = [(args.platform, default_dest)]
     elif args.dest:
         print(f"  Using destination: {args.dest}")
         platforms = [("retroarch", args.dest)]

tests/test_install.py

@@ -0,0 +1,171 @@
+"""Tests for install.py platform detection and config parsing."""
+from __future__ import annotations
+
+import importlib.util
+import json
+import os
+import tempfile
+import unittest
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).resolve().parent.parent
+_spec = importlib.util.spec_from_file_location("install", REPO_ROOT / "install.py")
+install = importlib.util.module_from_spec(_spec)
+_spec.loader.exec_module(install)
+
+
+class TestShellUnquote(unittest.TestCase):
+    def test_plain_value(self):
+        self.assertEqual(install._shell_unquote("/userdata/bios"), "/userdata/bios")
+
+    def test_double_quoted(self):
+        self.assertEqual(install._shell_unquote('"/home/deck/Emulation"'), "/home/deck/Emulation")
+
+    def test_single_quoted(self):
+        self.assertEqual(install._shell_unquote("'/home/deck/Emulation'"), "/home/deck/Emulation")
+
+    def test_concatenated_quoted_unquoted(self):
+        # EmuDeck SD card layout (issue: quote left in the middle of the path)
+        self.assertEqual(
+            install._shell_unquote('"/run/media/deck/EmuSD"/Emulation'),
+            "/run/media/deck/EmuSD/Emulation",
+        )
+
+    def test_concatenated_preserves_spaces_in_quotes(self):
+        self.assertEqual(
+            install._shell_unquote('"/run/media/deck/My Card"/Emulation'),
+            "/run/media/deck/My Card/Emulation",
+        )
+
+    def test_home_variable_expansion(self):
+        old = os.environ.get("HOME")
+        os.environ["HOME"] = "/home/deck"
+        try:
+            self.assertEqual(
+                install._shell_unquote('"$HOME"/Emulation'),
+                "/home/deck/Emulation",
+            )
+            self.assertEqual(
+                install._shell_unquote('"${HOME}/Emulation"'),
+                "/home/deck/Emulation",
+            )
+        finally:
+            if old is not None:
+                os.environ["HOME"] = old
+
+    def test_single_quotes_do_not_expand(self):
+        self.assertEqual(install._shell_unquote("'$HOME/x'"), "$HOME/x")
+
+    def test_trailing_comment(self):
+        self.assertEqual(install._shell_unquote("/data/bios # main dir"), "/data/bios")
+
+    def test_unquoted_stops_at_whitespace(self):
+        self.assertEqual(install._shell_unquote("/data/bios extra"), "/data/bios")
+
+    def test_tilde_expansion(self):
+        old = os.environ.get("HOME")
+        os.environ["HOME"] = "/home/deck"
+        try:
+            self.assertEqual(install._shell_unquote("~/Emulation"), "/home/deck/Emulation")
+        finally:
+            if old is not None:
+                os.environ["HOME"] = old
+
+
+class TestParseBashVar(unittest.TestCase):
+    def _write(self, content: str) -> Path:
+        fd, path = tempfile.mkstemp(suffix=".sh")
+        os.close(fd)
+        Path(path).write_text(content, encoding="utf-8")
+        self.addCleanup(os.unlink, path)
+        return Path(path)
+
+    def test_emudeck_sd_card_concatenation(self):
+        path = self._write(
+            'emulationPath="/run/media/deck/EmuSD"/Emulation\n'
+            'biosPath="/run/media/deck/EmuSD"/Emulation/bios\n'
+        )
+        self.assertEqual(
+            install._parse_bash_var(path, "emulationPath"),
+            "/run/media/deck/EmuSD/Emulation",
+        )
+        self.assertEqual(
+            install._parse_bash_var(path, "biosPath"),
+            "/run/media/deck/EmuSD/Emulation/bios",
+        )
+
+    def test_emudeck_home_variable(self):
+        old = os.environ.get("HOME")
+        os.environ["HOME"] = "/home/deck"
+        try:
+            path = self._write('emulationPath="$HOME"/Emulation\n')
+            self.assertEqual(
+                install._parse_bash_var(path, "emulationPath"),
+                "/home/deck/Emulation",
+            )
+        finally:
+            if old is not None:
+                os.environ["HOME"] = old
+
+    def test_missing_key(self):
+        path = self._write("other=1\n")
+        self.assertIsNone(install._parse_bash_var(path, "emulationPath"))
+
+    def test_missing_file(self):
+        self.assertIsNone(
+            install._parse_bash_var(Path("/nonexistent/settings.sh"), "emulationPath")
+        )
+
+
+class TestParseJsonPath(unittest.TestCase):
+    def _write(self, data) -> Path:
+        fd, path = tempfile.mkstemp(suffix=".json")
+        os.close(fd)
+        Path(path).write_text(
+            data if isinstance(data, str) else json.dumps(data), encoding="utf-8"
+        )
+        self.addCleanup(os.unlink, path)
+        return Path(path)
+
+    def test_retrodeck_rd_home_path(self):
+        path = self._write(
+            {"version": "1.0", "paths": {"rd_home_path": "/home/deck/retrodeck"}}
+        )
+        self.assertEqual(
+            install._parse_json_path(path, "paths", "rd_home_path"),
+            "/home/deck/retrodeck",
+        )
+
+    def test_missing_key_returns_none(self):
+        path = self._write({"paths": {}})
+        self.assertIsNone(install._parse_json_path(path, "paths", "rd_home_path"))
+
+    def test_invalid_json_returns_none(self):
+        path = self._write("{not json")
+        self.assertIsNone(install._parse_json_path(path, "paths", "rd_home_path"))
+
+    def test_empty_value_returns_none(self):
+        path = self._write({"paths": {"rd_home_path": ""}})
+        self.assertIsNone(install._parse_json_path(path, "paths", "rd_home_path"))
+
+    def test_missing_file(self):
+        self.assertIsNone(
+            install._parse_json_path(Path("/nonexistent/rd.json"), "paths", "rd_home_path")
+        )
+
+
+class TestDefaultDests(unittest.TestCase):
+    def test_retrodeck_defaults_to_rdhome(self):
+        self.assertEqual(
+            install.DEFAULT_DESTS["retrodeck"], Path.home() / "retrodeck"
+        )
+
+    def test_known_fixed_paths(self):
+        self.assertEqual(install.DEFAULT_DESTS["batocera"], Path("/userdata/bios"))
+        self.assertEqual(
+            install.DEFAULT_DESTS["recalbox"], Path("/recalbox/share/bios")
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()