init commit with repo structure and basic files

labeler/app/labeler.py

@@ -0,0 +1,25 @@
+from labeler.domain.objects import Label, LabelRequest, LabelDefinition
+from labeler.interfaces import Renderer, Printer
+
+
+class Application:
+    def __init__(self, renderer: Renderer, printer: Printer):
+        self.renderer = renderer
+        self.printer = printer
+
+    def render_preview(self, label_request: LabelRequest):
+        media = self.printer.get_installed_media()
+
+        if label_request.length is not None:
+            label_length = label_request.length - 2 * media.minimal_margin_horizontal
+        else:
+            label_length = media.printable_length
+
+        label_definition = LabelDefinition(
+            text=label_request.text,
+            length=label_length,
+            width=media.printable_width,
+            dpi=media.dpi,
+        )
+
+        self.renderer.render_label(label_definition)