Exported figures are in light mode independent of GUI styling

[MikeSullivan7]

Instead of exporting the current figures, a temporary figure is created and the data is replotted using matplotlib default style and figure colours are explicitly set.

Now, using the Dark Theme:

Exports the following plots:

Main Window:

Bayes plots:

[MikeSullivan7]

All colour changes in exported figures now happen after the figure is drawn:

In dark mode, the exported plots are displayed as follows:

[StephenNneji]

Works as advertised, the figure deep copy is still a bit slow but significantly better than before so we can live with it. thanks. please see comment below

[StephenNneji]

I suggest a refactor to get rid of hardcoded colours, let me know if it works

old_colours = matplotlib.rcParams["axes.prop_cycle"].by_key()["color"]
with matplotlib.style.context("default"):
    edge_colour = matplotlib.rcParams['axes.edgecolor']
    face_colour = matplotlib.rcParams['axes.facecolor']
    new_colours = matplotlib.rcParams["axes.prop_cycle"].by_key()["color"]
    colour_converter = dict(zip(old_colours, new_colours, strict=False))
    temp_fig = copy.deepcopy(self.figure)
    axes = temp_fig.axes
    for ax in axes:
        if not ax.get_visible():
            continue
        if ax.containers:
            for container in ax.containers:
                if isinstance(container, matplotlib.container.ErrorbarContainer):
                    _, __, (vertical_lines,) = container.lines
                    vertical_lines.set_color(
                        colour_converter[
                            matplotlib.colors.rgb2hex(vertical_lines.get_color(), keep_alpha=False)
                        ]
                    )
        ax.patch.set_facecolor(face_colour)
        for spine in ax.spines.values():
            spine.set_edgecolor(edge_colour)
        ax.tick_params(which="both", axis="both", color="black", labelcolor=edge_colour)
        ax.xaxis.label.set_color(edge_colour)
        ax.yaxis.label.set_color(edge_colour)
        ax.set_title(ax.get_title(loc="left"), color=edge_colour, loc="left")
        if ax.get_legend() is not None:
            ax.legend(facecolor="white", labelcolor=edge_colour)
            for line in ax.get_legend().get_lines():
                old_line_colour = line.get_color()
                line.set_color(colour_converter[old_line_colour])
        for line in ax.get_lines():
            old_line_colour = line.get_color()
            line.set_color(colour_converter[old_line_colour])

    temp_fig.savefig(filepath, facecolor=SETTINGS.export_background_colour, dpi=dpi)