app.py

import streamlit as st
from vitessce import VitessceConfig, AnnDataWrapper, ViewType as vt
import json

st.title("Vitessce AnnData-Zarr Explorer")

# 1) Pre‑fill from ?url=… in the browser query string
params = st.query_params
default_url = params.get("url", ["http://localhost:8000/pbmc_subset.zarr"])[0]
zarr_url = st.text_input("Zarr store URL:", default_url)





# 2) Build the VitessceConfig (note schema_version is required)
vc = VitessceConfig(schema_version="1.0.17", name="Dynamic Zarr Viewer")
dataset = (
    vc
    .add_dataset(name="PBMC 3k")
    .add_object(AnnDataWrapper(
        # Point this at your Zarr store
        adata_store=zarr_url,
        # Optional: tell it which obs/var fields to expose as cell sets, embeddings, etc.
        obs_set_paths=["obs/leiden"],
        obs_set_names=["Leiden"],
        obs_embedding_paths=["obsm/X_umap", "obsm/X_pca"],
        obs_embedding_names=["UMAP", "PCA"],
        obs_feature_matrix_path="X"
    ))
)

obs = vc.add_view(vt.OBS_SETS,   dataset=dataset)
vc.layout(obs)
# 3) Embed the viewer
cfg_json = json.dumps(vc.to_dict(base_url=""))
st.components.v1.html(
    f"""
    <link
      rel="stylesheet"
      href="https://unpkg.com/vitessce@latest/dist/css/vitessce.min.css"
    />
    <script src="https://unpkg.com/vitessce@latest/dist/js/vitessce.min.js"></script>
    <div id="v"></div>
    <script>
      const config = {cfg_json};
      Vitessce.create(document.getElementById("v"), config);
    </script>
    """,
    height=750,
)