Add package base and config loading

Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com>

4 files changed, 165 insertions, 0 deletions

diff --git a/generat3d/__init__.py b/generat3d/__init__.py
new file mode 100644
index 0000000..917b0c7
--- /dev/null
+++ b/generat3d/__init__.py
@@ -0,0 +1,28 @@
+# generat3D - evaluate Daz DSON scenes and write .dbz files
+# Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+import sys
+
+__version__ = "0.1.0"
+
+
+class Error(Exception):
+    """Fatal problem. The CLI prints it and exits 1."""
+
+
+def warn(msg):
+    print(f"generat3d: warning: {msg}", file=sys.stderr)
diff --git a/generat3d/config.py b/generat3d/config.py
new file mode 100644
index 0000000..9ea7266
--- /dev/null
+++ b/generat3d/config.py
@@ -0,0 +1,56 @@
+# generat3D - evaluate Daz DSON scenes and write .dbz files
+# Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+import os
+import tomllib
+from pathlib import Path
+
+from . import Error
+
+KEYS = {"library_roots"}
+
+
+def config_path():
+    base = os.environ.get("XDG_CONFIG_HOME") or os.path.expanduser("~/.config")
+    return Path(base) / "generat3d" / "config.toml"
+
+
+def library_roots(cli_roots, path=None):
+    """Library roots from -L if given (replacing the config), else from the config file."""
+    path = Path(path) if path else config_path()
+    roots = list(cli_roots)
+    if not roots and path.exists():
+        try:
+            with open(path, "rb") as f:
+                data = tomllib.load(f)
+        except tomllib.TOMLDecodeError as e:
+            raise Error(f"{path}: {e}") from None
+        unknown = sorted(set(data) - KEYS)
+        if unknown:
+            raise Error(f"{path}: unknown keys: {', '.join(unknown)}")
+        roots = data.get("library_roots", [])
+        if not isinstance(roots, list) or not all(isinstance(r, str) for r in roots):
+            raise Error(f"{path}: library_roots must be a list of strings")
+    if not roots:
+        raise Error(f"no library roots: pass -L or set library_roots in {path}")
+    out = []
+    for r in roots:
+        p = Path(r).expanduser()
+        if not p.is_dir():
+            raise Error(f"library root not found: {p}")
+        out.append(p)
+    return out
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/tests/__init__.py
diff --git a/tests/test_config.py b/tests/test_config.py
new file mode 100644
index 0000000..d1ad0d2
--- /dev/null
+++ b/tests/test_config.py
@@ -0,0 +1,81 @@
+# generat3D - evaluate Daz DSON scenes and write .dbz files
+# Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+import os
+import tempfile
+import unittest
+from pathlib import Path
+
+from generat3d import Error
+from generat3d.config import config_path, library_roots
+
+
+class ConfigTest(unittest.TestCase):
+    def setUp(self):
+        self.tmp = tempfile.TemporaryDirectory()
+        self.dir = Path(self.tmp.name)
+        self.lib = self.dir / "lib"
+        self.lib.mkdir()
+        self.cfg = self.dir / "config.toml"
+
+    def tearDown(self):
+        self.tmp.cleanup()
+
+    def write(self, text):
+        self.cfg.write_text(text)
+
+    def test_cli_roots_win_over_config(self):
+        self.write('library_roots = ["/nonexistent"]\n')
+        self.assertEqual(library_roots([str(self.lib)], self.cfg), [self.lib])
+
+    def test_roots_from_config(self):
+        self.write(f'library_roots = ["{self.lib}"]\n')
+        self.assertEqual(library_roots([], self.cfg), [self.lib])
+
+    def test_no_roots_anywhere(self):
+        with self.assertRaisesRegex(Error, "no library roots"):
+            library_roots([], self.cfg)
+
+    def test_missing_root_is_fatal(self):
+        with self.assertRaisesRegex(Error, "library root not found"):
+            library_roots([str(self.dir / "nope")], self.cfg)
+
+    def test_unknown_key_is_fatal(self):
+        self.write(f'library_roots = ["{self.lib}"]\nlibary = 1\n')
+        with self.assertRaisesRegex(Error, "unknown keys: libary"):
+            library_roots([], self.cfg)
+
+    def test_bad_type_is_fatal(self):
+        self.write('library_roots = "/x"\n')
+        with self.assertRaisesRegex(Error, "list of strings"):
+            library_roots([], self.cfg)
+
+    def test_bad_toml_is_fatal(self):
+        self.write("library_roots = [\n")
+        with self.assertRaisesRegex(Error, "config.toml"):
+            library_roots([], self.cfg)
+
+    def test_xdg_config_home(self):
+        old = os.environ.get("XDG_CONFIG_HOME")
+        os.environ["XDG_CONFIG_HOME"] = "/tmp/xdg"
+        try:
+            self.assertEqual(config_path(), Path("/tmp/xdg/generat3d/config.toml"))
+        finally:
+            if old is None:
+                del os.environ["XDG_CONFIG_HOME"]
+            else:
+                os.environ["XDG_CONFIG_HOME"] = old