implementing replace_picture()

.gitignore

@@ -90,7 +90,8 @@ target/
 #   However, in case of collaboration, if having platform-specific dependencies or dependencies
 #   having no cross-platform support, pipenv may install dependencies that don't work, or not
 #   install all needed dependencies.
-#Pipfile.lock
+Pipfile
+Pipfile.lock
 
 # celery beat schedule file
 celerybeat-schedule
@@ -128,4 +129,7 @@ dmypy.json
 # Ignore all local history of files
 .history
 
+### PyCharm ###
+.idea/*
+
 # End of https://www.gitignore.io/api/python,jupyternotebooks,visualstudiocode

playground/testing_1.py

@@ -0,0 +1,64 @@
+from pathlib import Path
+from typing import List
+
+from pptx import Presentation
+from pptx.shapes.autoshape import BaseShape
+from pptx.slide import Slide
+
+example_file_path = Path("./data/example01.pptx").resolve()
+prs = Presentation(example_file_path)
+print(prs)
+
+
+def get_shape_info(shape: BaseShape) -> dict:
+    return {
+        "name": shape.name,
+        "text": shape.text if shape.has_text_frame else None,
+        "width": shape.width,
+        "height": shape.height,
+        "id": shape.shape_id,
+        "x": shape.left,
+        "y": shape.top,
+        "type": type(shape),
+    }
+
+
+slide_info = [get_shape_info(shape) for shape in prs.slides[0].shapes]
+print(slide_info)
+
+
+def replace_by_image(slide: Slide, name: str, img_path: Path, *, do_not_scale: bool = False) -> List[BaseShape]:
+    shapes_to_replace = [shape for shape in slide.shapes if hasattr(shape, "text") and shape.text == name]
+    print(len(shapes_to_replace))
+    new_image_shapes = []
+    for old_shape in shapes_to_replace:
+        shape_info = get_shape_info(old_shape)
+        print(shape_info)
+        img_file = open(img_path, "rb")
+        slide_shapes = old_shape._parent
+        img_shape = slide_shapes.add_picture(
+            img_file,
+            old_shape.left,
+            old_shape.top,
+        )
+        old_aspect_ratio = old_shape.width / old_shape.height
+        new_aspect_ratio = img_shape.width / img_shape.height
+        if img_shape.height <= old_shape.height and img_shape.width <= old_shape.width and not do_not_scale:
+            if old_aspect_ratio >= new_aspect_ratio:
+                img_shape.width = old_shape.width
+                img_shape.height = int(img_shape.width / new_aspect_ratio)
+            else:
+                img_shape.height = old_shape.height
+                img_shape.width = int(img_shape.height * new_aspect_ratio)
+        img_shape.top += int((old_shape.height - img_shape.height) / 2)
+        img_shape.left += int((old_shape.width - img_shape.width) / 2)
+        new_image_shapes.append(img_shape)
+        slide_shapes.element.remove(old_shape.element)
+    return new_image_shapes
+
+
+added_img_shapes = replace_by_image(prs.slides[0], "#logo", Path("./playground/pptx_icon.png"))
+assert len(added_img_shapes) == 1
+added_img_shapes = replace_by_image(prs.slides[0], "#logo", Path("./playground/pptx_icon.png"))
+assert len(added_img_shapes) == 0
+prs.save(Path("./playground") / example_file_path.name)

pptx_blueprint/__init__.py

@@ -30,14 +30,47 @@ def replace_text(self, label: str, text: str, *, scope=None) -> None:
         """
         pass
 
-    def replace_picture(self, label: str, filename: _Pathlike) -> None:
+    def replace_picture(self, label: str, filename: _Pathlike, *, do_not_scale_up: bool = False) -> None:
         """Replaces rectangle placeholders on one or many slides.
 
         Args:
             label (str): label of the placeholder (without curly braces)
             filename (path-like): path to an image file
+            do_not_scale_up (bool): deactivates that the image is enlarged (default: False)
         """
-        pass
+        shapes_to_replace = self._find_shapes(label)
+        if not shapes_to_replace:
+            return
+        if isinstance(filename, str):
+            filename = pathlib.Path(filename)
+        if not filename.is_file():
+            raise FileNotFoundError(f"The file does not exist: {filename}")
+        img_file = open(filename, "rb")
+        old_shape: BaseShape
+        for old_shape in shapes_to_replace:
+            slide_shapes = old_shape._parent
+            img_shape = slide_shapes.add_picture(
+                image_file=img_file,
+                left=old_shape.left,
+                top=old_shape.top,
+            )
+            # Scaling the image if `do_not_scale == False`:
+            if img_shape.height <= old_shape.height and img_shape.width <= old_shape.width and not do_not_scale_up:
+                old_aspect_ratio = old_shape.width / old_shape.height
+                new_aspect_ratio = img_shape.width / img_shape.height
+                if old_aspect_ratio >= new_aspect_ratio:
+                    img_shape.width = old_shape.width
+                    img_shape.height = int(img_shape.width / new_aspect_ratio)
+                else:
+                    img_shape.height = old_shape.height
+                    img_shape.width = int(img_shape.height * new_aspect_ratio)
+            # Centering the image at the extent of the placeholder:
+            img_shape.top += int((old_shape.height - img_shape.height) / 2)
+            img_shape.left += int((old_shape.width - img_shape.width) / 2)
+            del slide_shapes[slide_shapes.index(old_shape)]
+            # Removing shapes is performed at the lxml level.
+            # The `element` attribute contains an instance of `lxml.etree._Element`.
+            slide_shapes.element.remove(old_shape.element)
 
     def replace_table(self, label: str, data) -> None:
         """Replaces rectangle placeholders on one or many slides.