Merge pull request #494 from chinapandaman/PPF-493

PPF-493: allow users to specify grid view margin

PyPDFForm/core/constants.py

@@ -39,4 +39,4 @@
     "l": "\u25CF",
 }
 
-COORDINATE_GRID_MARGIN = 100
+COORDINATE_GRID_FONT_SIZE_MARGIN_RATIO = DEFAULT_FONT_SIZE / 100

PyPDFForm/core/coordinate.py

@@ -8,8 +8,8 @@
 from reportlab.pdfbase.pdfmetrics import stringWidth
 
 from ..middleware.text import Text
-from .constants import (ANNOTATION_RECTANGLE_KEY, COORDINATE_GRID_MARGIN,
-                        DEFAULT_FONT, DEFAULT_FONT_SIZE)
+from .constants import (ANNOTATION_RECTANGLE_KEY, COORDINATE_GRID_FONT_SIZE_MARGIN_RATIO,
+                        DEFAULT_FONT)
 from .template import (get_char_rect_width, get_widget_alignment,
                        is_text_multiline)
 from .utils import stream_to_io
@@ -158,7 +158,7 @@ def get_text_line_x_coordinates(
     return None
 
 
-def generate_coordinate_grid(pdf: bytes, color: Tuple[float, float, float]) -> bytes:
+def generate_coordinate_grid(pdf: bytes, color: Tuple[float, float, float], margin: float) -> bytes:
     """Creates a grid view for the coordinates of a PDF."""
 
     pdf_file = PdfReader(stream_to_io(pdf))
@@ -174,34 +174,35 @@ def generate_coordinate_grid(pdf: bytes, color: Tuple[float, float, float]) -> b
 
         r, g, b = color
 
-        current = COORDINATE_GRID_MARGIN
+        current = margin
         while current < width:
             lines_by_page[i + 1].append([current, 0, current, height, r, g, b])
-            current += COORDINATE_GRID_MARGIN
+            current += margin
 
-        current = COORDINATE_GRID_MARGIN
+        current = margin
         while current < height:
             lines_by_page[i + 1].append([0, current, width, current, r, g, b])
-            current += COORDINATE_GRID_MARGIN
+            current += margin
 
-        x = COORDINATE_GRID_MARGIN
+        x = margin
         while x < width:
-            y = COORDINATE_GRID_MARGIN
+            y = margin
             while y < height:
                 value = f"({x}, {y})"
+                font_size = margin * COORDINATE_GRID_FONT_SIZE_MARGIN_RATIO
                 text = Text("new_coordinate", value)
                 text.font = DEFAULT_FONT
-                text.font_size = DEFAULT_FONT_SIZE
+                text.font_size = font_size
                 text.font_color = color
                 texts_by_page[i + 1].append(
                     [
                         text,
-                        x - stringWidth(value, DEFAULT_FONT, DEFAULT_FONT_SIZE),
-                        y - DEFAULT_FONT_SIZE,
+                        x - stringWidth(value, DEFAULT_FONT, font_size),
+                        y - font_size,
                     ]
                 )
-                y += COORDINATE_GRID_MARGIN
-            x += COORDINATE_GRID_MARGIN
+                y += margin
+            x += margin
 
     for page, lines in lines_by_page.items():
         watermarks.append(

PyPDFForm/wrapper.py

@@ -137,7 +137,7 @@ def preview(self) -> bytes:
         )
 
     def generate_coordinate_grid(
-        self, color: Tuple[float, float, float] = (1, 0, 0)
+        self, color: Tuple[float, float, float] = (1, 0, 0), margin: float = 100
     ) -> PdfWrapper:
         """Inspects a coordinate grid of the PDF."""
 
@@ -146,6 +146,7 @@ def generate_coordinate_grid(
                 remove_all_widgets(self.read()), widget_rect_watermarks(self.read())
             ),
             color,
+            margin,
         )
 
         return self

docs/coordinate.md

@@ -17,11 +17,12 @@ from PyPDFForm import PdfWrapper
 
 grid_view_pdf = PdfWrapper(
     "sample_template.pdf"
-).generate_coordinate_grid(color=(1, 0, 0))
+).generate_coordinate_grid(color=(1, 0, 0), margin=100)
 
 with open("output.pdf", "wb+") as output:
     output.write(grid_view_pdf.read())
 ```
 
-The `generate_coordinate_grid` method takes one optional parameter `color` which allows you to pick a color for 
-the grid view. The default color is red.
+The `generate_coordinate_grid` method takes two optional parameters. The first one is `color` which allows you to pick 
+a color for the grid view. The default color is red. The second one is `margin` which allows you to change the 
+coordinate grid view's margin in points. The default margin is 100 points.

tests/test_functional.py

@@ -513,3 +513,17 @@ def test_generate_coordinate_grid(template_stream, pdf_samples, request):
 
         assert len(obj.read()) == len(expected)
         assert obj.stream == expected
+
+
+def test_generate_coordinate_grid_margin_50(template_stream, pdf_samples, request):
+    expected_path = os.path.join(pdf_samples, "test_generate_coordinate_grid_margin_50.pdf")
+    with open(expected_path, "rb+") as f:
+        obj = PdfWrapper(template_stream).generate_coordinate_grid((1, 0, 1), margin=50)
+
+        request.config.results["expected_path"] = expected_path
+        request.config.results["stream"] = obj.read()
+
+        expected = f.read()
+
+        assert len(obj.read()) == len(expected)
+        assert obj.stream == expected