plot: review base plot to support multiple objects

Author: M3nin0

pysits/visualization/base.py

@@ -18,9 +18,12 @@
 """Base visualization utilities."""
 
 import os
+import shutil
 import tempfile
 from typing import Any, TypeAlias
 
+from rpy2.robjects import ListVector
+
 from pysits.backend.functions import r_fnc_plot
 from pysits.backend.pkgs import r_pkg_grdevices
 from pysits.visualization.image import show_local_image
@@ -34,11 +37,12 @@
 #
 # Utility function
 #
-def _base_plot(data: Any, image_args: ImageArgs | None = None, **kwargs: Any) -> str:
+def _base_plot(data: Any, image_args: ImageArgs | None = None, **kwargs: Any) -> None:
     """Save and show images created using base plot.
 
-    This function creates a temporary PNG file from an R plot object and displays it.
+    This function creates temporary PNG files from R plot objects and displays them.
     It handles the configuration of the image device, plotting, and cleanup.
+    The function handles multiple plots returned by r_fnc_plot as a ListVector.
 
     Args:
         data: The R object to be plotted.
@@ -53,15 +57,10 @@ def _base_plot(data: Any, image_args: ImageArgs | None = None, **kwargs: Any) ->
         **kwargs: Additional keyword arguments passed to R's base::plot function.
 
     Returns:
-        str: Absolute path to the saved temporary PNG image file.
-
-    Note:
-        The function creates a temporary directory and file that should be cleaned up
-        after use. The image is displayed using the ``show_local_image`` function.
+        None: Nothing.
     """
     # Create a temporary directory
     temp_dir = tempfile.mkdtemp()
-    file_path = os.path.join(temp_dir, "base_plot.jpeg")
 
     # Process image args
     image_args = image_args if image_args else {}
@@ -71,20 +70,45 @@ def _base_plot(data: Any, image_args: ImageArgs | None = None, **kwargs: Any) ->
     image_width = int(image_args.get("width", 10) * image_res)
     image_height = int(image_args.get("height", 6) * image_res)
 
-    # Enable image device
-    r_pkg_grdevices.jpeg(
-        file=file_path, width=image_width, height=image_height, res=image_res
-    )
+    # Plot data
+    plots = r_fnc_plot(data, **kwargs)
+
+    # Handle plots
+    if isinstance(plots, ListVector):
+        for i, plot in enumerate(plots):
+            file_path = os.path.join(temp_dir, f"base_plot_{i}.jpeg")
+
+            # Enable image device
+            r_pkg_grdevices.jpeg(
+                file=file_path, width=image_width, height=image_height, res=image_res
+            )
+
+            # Plot the plot object directly
+            r_fnc_plot(plot[0])
 
-    # Save the tmap plot using R
-    r_fnc_plot(data, **kwargs)
+            r_pkg_grdevices.dev_off()
 
-    r_pkg_grdevices.dev_off()
+            # Display saved image
+            show_local_image(file_path)
 
-    # Display the saved image
-    show_local_image(file_path)
+    else:
+        file_path = os.path.join(temp_dir, "base_plot.jpeg")
 
-    return file_path
+        # Enable image device
+        r_pkg_grdevices.jpeg(
+            file=file_path, width=image_width, height=image_height, res=image_res
+        )
+
+        # Save plot using R
+        r_fnc_plot(plots)
+
+        r_pkg_grdevices.dev_off()
+
+        # Display saved image
+        show_local_image(file_path)
+
+    # Clean up temporary directory
+    shutil.rmtree(temp_dir)
 
 
 #
@@ -93,7 +117,7 @@ def _base_plot(data: Any, image_args: ImageArgs | None = None, **kwargs: Any) ->
 def plot_base(
     instance: Any, image_args: ImageArgs | None = None, **kwargs: Any
 ) -> None:
-    """Generate and display a base R plot.
+    """Generate and display base R plots.
 
     This is a high-level function that wraps ``_base_plot`` to create and display
     a plot using R's base plotting system. It handles the creation of a temporary
@@ -113,10 +137,6 @@ def plot_base(
 
     Returns:
         None: Nothing.
-
-    Note:
-        The function creates a temporary directory and file that should be cleaned up
-        after use. The image is displayed using the ``show_local_image`` function.
     """
-    # Save and display the plot
+    # Save and display plot
     _base_plot(instance, image_args=image_args, **kwargs)