app.py

from pathlib import Path
from typing import List, Dict, Tuple
import matplotlib.colors as mpl_colors

import pandas as pd
import seaborn as sns
import shinyswatch

from shiny import App, Inputs, Outputs, Session, reactive, render, req, ui

from transformers import SamModel, SamConfig, SamProcessor
import torch

sns.set_theme()

www_dir = Path(__file__).parent.resolve() / "www"

df = pd.read_csv(Path(__file__).parent / "penguins.csv", na_values="NA")
numeric_cols: List[str] = df.select_dtypes(include=["float64"]).columns.tolist()
species: List[str] = df["Species"].unique().tolist()
species.sort()

app_ui = ui.page_fillable(
    shinyswatch.theme.minty(),
    ui.layout_sidebar(
        ui.sidebar(
            ui.input_file("tile_image", "Choose TIFF File", accept=[".tif"], multiple=False),
            # Artwork by @allison_horst
            ui.input_selectize(
                "xvar",
                "X variable",
                numeric_cols,
                selected="Bill Length (mm)",
            ),
            ui.input_selectize(
                "yvar",
                "Y variable",
                numeric_cols,
                selected="Bill Depth (mm)",
            ),
            ui.input_checkbox_group(
                "species", "Filter by species", species, selected=species
            ),
            ui.hr(),
            ui.input_switch("by_species", "Show species", value=True),
            ui.input_switch("show_margins", "Show marginal plots", value=True),
        ),
        ui.output_image("uploaded_image"),  # display the uploaded TIFF sidewalk tile image
        ui.output_ui("value_boxes"),
        ui.output_plot("scatter", fill=True),
        ui.help_text(
            "Artwork by ",
            ui.a("@allison_horst", href="https://twitter.com/allison_horst"),
            class_="text-end",
        ),
    ),
)


def server(input: Inputs, output: Outputs, session: Session):
    # Load the model configuration
    model_config = SamConfig.from_pretrained("facebook/sam-vit-base")
    processor = SamProcessor.from_pretrained("facebook/sam-vit-base")
    
    # Create an instance of the model from my fine-tuned model with the loaded configuration
    model = SamModel.from_pretrained("aagoluoglu/SAM_Sidewalks", config=model_config)
    
    # set the device to cuda if available, otherwise use cpu
    device = "cuda" if torch.cuda.is_available() else "cpu"
    model.to(device)
    
    @reactive.Calc
    def uploaded_image_path() -> str:
        """Returns the path to the uploaded image"""
        if input.tile_image() is not None:
            return input.tile_image()[0]['datapath']  # Assuming multiple=False
        else:
            return ""  # No image uploaded

    @render.image
    def uploaded_image():
        """Displays the uploaded image"""
        from pathlib import Path

        img_src = uploaded_image_path()
        if img_src:
            dir = Path(__file__).resolve().parent
            img: ImgData = {"src": str(dir / uploaded_image_path()), "width": "100px"}
            return img
        else:
            return None  # Return an empty string if no image is uploaded
    
    @reactive.Calc
    def filtered_df() -> pd.DataFrame:
        """Returns a Pandas data frame that includes only the desired rows"""

        # This calculation "req"uires that at least one species is selected
        req(len(input.species()) > 0)

        # Filter the rows so we only include the desired species
        return df[df["Species"].isin(input.species())]

    @output
    @render.plot
    def scatter():
        """Generates a plot for Shiny to display to the user"""

        # The plotting function to use depends on whether margins are desired
        plotfunc = sns.jointplot if input.show_margins() else sns.scatterplot

        plotfunc(
            data=filtered_df(),
            x=input.xvar(),
            y=input.yvar(),
            palette=palette,
            hue="Species" if input.by_species() else None,
            hue_order=species,
            legend=False,
        )

    @output
    @render.ui
    def value_boxes():
        df = filtered_df()

        def penguin_value_box(title: str, count: int, bgcol: str, showcase_img: str):
            return ui.value_box(
                title,
                count,
                {"class_": "pt-1 pb-0"},
                showcase=ui.fill.as_fill_item(
                    ui.tags.img(
                        {"style": "object-fit:contain;"},
                        src=showcase_img,
                    )
                ),
                theme_color=None,
                style=f"background-color: {bgcol};",
            )

        if not input.by_species():
            return penguin_value_box(
                "Penguins",
                len(df.index),
                bg_palette["default"],
                # Artwork by @allison_horst
                showcase_img="penguins.png",
            )

        value_boxes = [
            penguin_value_box(
                name,
                len(df[df["Species"] == name]),
                bg_palette[name],
                # Artwork by @allison_horst
                showcase_img=f"{name}.png",
            )
            for name in species
            # Only include boxes for _selected_ species
            if name in input.species()
        ]

        return ui.layout_column_wrap(*value_boxes, width = 1 / len(value_boxes))


# "darkorange", "purple", "cyan4"
colors = [[255, 140, 0], [160, 32, 240], [0, 139, 139]]
colors = [(r / 255.0, g / 255.0, b / 255.0) for r, g, b in colors]

palette: Dict[str, Tuple[float, float, float]] = {
    "Adelie": colors[0],
    "Chinstrap": colors[1],
    "Gentoo": colors[2],
    "default": sns.color_palette()[0],  # type: ignore
}

bg_palette = {}
# Use `sns.set_style("whitegrid")` to help find approx alpha value
for name, col in palette.items():
    # Adjusted n_colors until `axe` accessibility did not complain about color contrast
    bg_palette[name] = mpl_colors.to_hex(sns.light_palette(col, n_colors=7)[1])  # type: ignore


app = App(
    app_ui,
    server,
    static_assets=str(www_dir),
)