app.py

import gradio as gr
import importlib
import os

from data.options import iso_options, rp_options
from data.geometry import fetch_gis_subdivisions, has_associated_features
from data.hotosm import download_hotosm_data
from data.ckan import download_resource_ckan

from analysis import run_analyses

# Discover available hazard modules dynamically
def get_available_hazards():
    hazard_dir = "hazards"
    files = os.listdir(hazard_dir)
    hazards = [
        f.replace(".py", "") for f in files
        if f.endswith(".py") and f != "__init__.py"
    ]
    return sorted([(h.capitalize(), h) for h in hazards])

hazard_options = get_available_hazards()

# Gradio app
with gr.Blocks(title="Hazard Raster Downloader") as demo:
    gr.Markdown("## eVCA Hazard and Exposure Data Downloader\nSelect a country, hazard, and return period to generate hazard rasters and supporting exposure data.")

    with gr.Row():
        hazard_input = gr.Dropdown(choices=hazard_options, label="Hazard", value="flood", interactive=True)
        iso_input = gr.Dropdown(choices=iso_options, label="Country", interactive=True, value=None)
        rp_input = gr.Dropdown(choices=rp_options, label="Return Period (years)", value=10)

    subdivision_input = gr.Dropdown(choices=[], label="Subdivision", interactive=True, visible=False)

    generate_btn = gr.Button("Generate Raster", visible=False)
    status_text = gr.Markdown("")
    file_output = gr.Files(label="Downloads", interactive=False)
    analysis_output = gr.Markdown("", label="Analysis Results")

    def wrapper(hazard, iso, rp, subdivision):
        # Dynamic import of selected hazard module
        try:
            hazard_module = importlib.import_module(f"hazards.{hazard}")
            generate_func = getattr(hazard_module, f"generate_{hazard}_raster")
        except (ModuleNotFoundError, AttributeError):
            return [], f"❌ Error: No raster generation function found for hazard '{hazard}'."
        
        # Extract just the subdivision name if it's not the country-level option
        subdivision_name = None
        if subdivision and not subdivision.endswith("(Country level)"):
            subdivision_name = subdivision
        
        # Generate raster
        raster_path, msg = generate_func(iso, rp, subdivision_name)

        iso3 = iso.split(",")[-1].strip() if "," in iso else iso

        # HOTOSM Downloads
        pp_path = download_hotosm_data(iso3, feature_type="populated_places", geometry="points")
        roads_path = download_hotosm_data(iso3, feature_type="roads", geometry="lines")
        buildings_path = download_hotosm_data(iso3, feature_type="buildings", geometry="polygons")

        # CKAN Downloads
        pop_paths = download_resource_ckan(iso3, dataset_prefix="cod-ps")
        admin_path = download_resource_ckan(iso3, dataset_prefix="cod-ab")

        files = []
        if raster_path:
            files.append(raster_path)
        if pp_path:
            files.append(pp_path)
        if roads_path:
            files.append(roads_path)
        if buildings_path:
            files.append(buildings_path)
        if admin_path:
            files.extend(admin_path)
        if pop_paths:
            files.extend(pop_paths)
        # Run all available analyses
        analysis_results = run_analyses(
            raster_path=raster_path,
            pp_path=pp_path,
            roads_path=roads_path,
            buildings_path=buildings_path,
            admin_path=admin_path,
            pop_paths=pop_paths
        )
        
        if analysis_results:
            analysis_msg = analysis_results
        else:
            analysis_msg = "✅ No analyses could be run."
        
        if not files:
            msg += " ⚠️ No data could be downloaded."
        return files, msg, analysis_msg

    def get_subdivision_options(iso_code):
        has_features, data = has_associated_features(iso_code)
        subdivisions = fetch_gis_subdivisions(iso_code)

        # Lookup the country name from iso_options
        country_name = next((name for name, code in iso_options if code == iso_code), iso_code)

        if not has_features:
            # Only subdivisions available
            return (
                gr.update(choices=subdivisions, visible=True, value=None),
                gr.update(visible=False),
                gr.update(value=f"✅ Subdivisions loaded for {country_name}. Please select one.")
            )
        else:
            # Add the whole country as the first option
            country_option = f"{country_name} (Country level)"
            return (
                gr.update(choices=[country_option] + subdivisions, visible=True, value=country_option),
                gr.update(visible=False),
                gr.update(value=f"✅ Country and subdivisions loaded for {country_name}. You may choose either.")
            )

    iso_input.change(
        fn=lambda iso: gr.update(value="🔄 Loading subdivisions..."),
        inputs=iso_input,
        outputs=status_text
    ).then(
        fn=get_subdivision_options,
        inputs=iso_input,
        outputs=[subdivision_input, generate_btn, status_text]
    )

    subdivision_input.change(
        fn=lambda s: gr.update(visible=True) if s else gr.update(visible=False),
        inputs=subdivision_input,
        outputs=generate_btn
    )

    generate_btn.click(
        fn=wrapper,
        inputs=[hazard_input, iso_input, rp_input, subdivision_input],
        outputs=[file_output, status_text, analysis_output]
    )

if __name__ == "__main__":
    demo.launch(share=True)