Add CWA_ENABLED to run Bindery without CWA

With CWA_ENABLED=false, Bindery ignores the CWA settings, makes no request
to CWA, and shows nothing about CWA in the log and the web interface. A
set INGEST_DIR still gets each changed book as a plain epub.

Without it, the log names each CWA function that a missing setting turns
off.

tests/test_config.py

@@ -104,6 +104,7 @@ def test_defaults(monkeypatch, reload_config):
         "PROXY_AUTH_TRUSTED_IPS",
         "ALLOWED_HOSTS",
         "BINDERY_ADMIN_USERS",
+        "CWA_ENABLED",
         "SESSION_COOKIE_SECURE",
         "TRUST_PROXY",
         "CWA_DB_PATH",
@@ -131,6 +132,8 @@ def test_defaults(monkeypatch, reload_config):
     ]
     assert config.ALLOWED_HOSTS == []
     assert config.ADMIN_USERS == []
+    assert config.CWA_ENABLED is True
+    assert config.IGNORED_SETTINGS == []
     assert config.SESSION_COOKIE_SECURE is False
     assert config.TRUST_PROXY is False
     assert config.CWA_DB_PATH is None
@@ -147,7 +150,76 @@ def test_empty_ingest_directory_disables_uploads(monkeypatch, reload_config, val
     assert config.INGEST_DIR is None
 
 
+@pytest.mark.parametrize("value", ["false", " No ", "0", "off"])
+def test_cwa_off_ignores_the_cwa_settings_but_not_the_ingest_folder(monkeypatch, reload_config, value):
+    monkeypatch.setenv("CWA_ENABLED", value)
+    monkeypatch.setenv("CWA_URL", "https://cwa.invalid")
+    monkeypatch.setenv("CWA_USERNAME", "bindery")
+    monkeypatch.setenv("CWA_PASSWORD", "secret")
+    monkeypatch.setenv("CWA_DB_PATH", "/cwa/app.db")
+    monkeypatch.setenv("CALIBRE_DB_PATH", "/library/metadata.db")
+    monkeypatch.setenv("INGEST_DIR", "/books")
+    reload_config()
+    assert config.CWA_ENABLED is False
+    assert (config.CWA_URL, config.CWA_USERNAME, config.CWA_PASSWORD) == ("", "", "")
+    assert (config.CWA_DB_PATH, config.CALIBRE_DB_PATH) == (None, None)
+    assert config.IGNORED_SETTINGS == ["CWA_URL", "CWA_USERNAME", "CWA_PASSWORD", "CWA_DB_PATH", "CALIBRE_DB_PATH"]
+    assert str(config.INGEST_DIR) == "/books"
+
+
+@pytest.mark.parametrize("value", ["", "true", "maybe"])
+def test_only_a_clear_false_turns_cwa_off(monkeypatch, reload_config, value):
+    monkeypatch.setenv("CWA_ENABLED", value)
+    monkeypatch.setenv("CWA_URL", "https://cwa.invalid")
+    reload_config()
+    assert config.CWA_ENABLED is True
+    assert config.CWA_URL == "https://cwa.invalid"
+
+
+@pytest.mark.parametrize("ignored", [[], ["CWA_URL", "CALIBRE_DB_PATH"]])
+def test_prepare_with_cwa_off_logs_nothing_about_missing_cwa(monkeypatch, tmp_path, caplog, ignored):
+    monkeypatch.setattr(config, "CWA_ENABLED", False)
+    monkeypatch.setattr(config, "IGNORED_SETTINGS", ignored)
+    monkeypatch.setattr(config, "INGEST_DIR", None)
+    monkeypatch.setattr(config, "CWA_URL", "")
+    monkeypatch.setattr(config, "CALIBRE_DB_PATH", None)
+    for name, folder in [("CONFIG_DIR", "config"), ("UPLOAD_DIR", "uploads"), ("TMP_DIR", "tmp")]:
+        monkeypatch.setattr(config, name, tmp_path / folder)
+    monkeypatch.setattr(config, "PERSONAL_INI", tmp_path / "config" / "personal.ini")
+    with caplog.at_level("INFO"):
+        config.prepare()
+    lines = [r.getMessage() for r in caplog.records]
+    expected = ["CWA_ENABLED is false. Bindery ignores CWA_URL, CALIBRE_DB_PATH."] if ignored else []
+    assert [line for line in lines if "CWA" in line or "INGEST" in line] == expected
+
+
+@pytest.mark.parametrize(
+    ("ingest", "url", "database", "expected"),
+    [
+        (False, "", None, ["INGEST_DIR is not set", "cannot find the library book of a story.", "CWA_ENABLED=false"]),
+        (True, "", None, ["so each update adds a new book to CWA.", "CWA_ENABLED=false"]),
+        (True, "", Path("/library/metadata.db"), ["CWA_URL is not set. Bindery cannot search", "CWA_ENABLED=false"]),
+        (False, "https://cwa.invalid", None, ["INGEST_DIR is not set", "CWA_ENABLED=false"]),
+        (True, "https://cwa.invalid", None, []),
+    ],
+)
+def test_prepare_warns_about_each_missing_cwa_function(monkeypatch, tmp_path, caplog, ingest, url, database, expected):
+    monkeypatch.setattr(config, "CWA_URL", url)
+    monkeypatch.setattr(config, "CALIBRE_DB_PATH", database)
+    monkeypatch.setattr(config, "INGEST_DIR", tmp_path if ingest else None)
+    for name, folder in [("CONFIG_DIR", "config"), ("UPLOAD_DIR", "uploads"), ("TMP_DIR", "tmp")]:
+        monkeypatch.setattr(config, name, tmp_path / folder)
+    monkeypatch.setattr(config, "PERSONAL_INI", tmp_path / "config" / "personal.ini")
+    with caplog.at_level("WARNING"):
+        config.prepare()
+    warnings = [r.getMessage() for r in caplog.records]
+    assert len(warnings) == len(expected)
+    for warning, text in zip(warnings, expected, strict=True):
+        assert text in warning
+
+
 def test_prepare_without_cwa_creates_only_bindery_folders(monkeypatch, tmp_path, caplog):
+    monkeypatch.setattr(config, "CWA_ENABLED", False)
     monkeypatch.setattr(config, "INGEST_DIR", None)
     monkeypatch.setattr(config, "CWA_URL", "")
     monkeypatch.setattr(config, "CALIBRE_DB_PATH", None)