import streamlit as st
import geopandas as gpd
import folium
import zipfile
import tempfile
import os
from streamlit_folium import st_folium
from shapely.geometry import LineString

st.set_page_config(page_title="GIS Viewer", layout="wide")

st.title("🗺️ GIS Viewer with Connected Points")

st.markdown("Upload a GeoJSON, KMZ, or zipped Shapefile. This app will connect every 2 consecutive points with a solid line.")

uploaded_file = st.file_uploader("Upload GeoJSON, KMZ or zipped Shapefile", type=["geojson", "zip", "kmz"])

def load_geodata(file):
    ext = file.name.lower()
    with tempfile.TemporaryDirectory() as tmpdir:
        if ext.endswith(".geojson"):
            gdf = gpd.read_file(file)
        elif ext.endswith(".zip"):
            with zipfile.ZipFile(file, "r") as z:
                z.extractall(tmpdir)
                shp_files = [f for f in os.listdir(tmpdir) if f.endswith(".shp")]
                if not shp_files:
                    raise Exception("No .shp file found in ZIP.")
                gdf = gpd.read_file(os.path.join(tmpdir, shp_files[0]))
        elif ext.endswith(".kmz"):
            with zipfile.ZipFile(file, "r") as z:
                z.extractall(tmpdir)
                kml_files = [f for f in os.listdir(tmpdir) if f.endswith(".kml")]
                if not kml_files:
                    raise Exception("No .kml file found inside KMZ.")
                gdf = gpd.read_file(os.path.join(tmpdir, kml_files[0]))
        else:
            raise Exception("Unsupported file format.")
        if gdf.crs and gdf.crs.to_epsg() != 4326:
            gdf = gdf.to_crs(epsg=4326)
        return gdf

def create_lines_from_points(points_gdf):
    lines = []
    for i in range(0, len(points_gdf) - 1, 2):
        p1 = points_gdf.iloc[i].geometry
        p2 = points_gdf.iloc[i+1].geometry
        if p1.geom_type == "Point" and p2.geom_type == "Point":
            line = LineString([p1, p2])
            lines.append({"geometry": line})
    return gpd.GeoDataFrame(lines, geometry="geometry", crs="EPSG:4326")

if uploaded_file:
    try:
        with st.spinner("Processing file..."):
            gdf = load_geodata(uploaded_file)

        st.success("File loaded successfully!")

        # Filter only points
        point_gdf = gdf[gdf.geometry.type == "Point"].reset_index(drop=True)
        line_gdf = create_lines_from_points(point_gdf)

        # Map setup
        center = gdf.geometry.unary_union.centroid
        m = folium.Map(location=[center.y, center.x], zoom_start=10)

        folium.GeoJson(gdf, name="Features",
                       tooltip=folium.GeoJsonTooltip(fields=gdf.columns[:3].tolist())).add_to(m)

        # Add lines between points
        folium.GeoJson(line_gdf, name="Lines Between Points",
                       style_function=lambda x: {"color": "red", "weight": 3}).add_to(m)

        # Add point markers
        for idx, row in point_gdf.iterrows():
            coords = row.geometry.coords[0]
            folium.Marker(
                location=[coords[1], coords[0]],
                popup=f"Point {idx+1} - ({coords[1]}, {coords[0]})",
                icon=folium.Icon(color="blue", icon="info-sign")
            ).add_to(m)

        folium.LayerControl().add_to(m)

        st.subheader("🌍 Map Viewer")
        st_folium(m, width=1100, height=600)

        st.subheader("📍 Points Table")
        st.dataframe(point_gdf)

        st.subheader("📋 Full Attribute Table")
        st.dataframe(gdf)

    except Exception as e:
        st.error(f"Error: {e}")
else:
    st.info("Please upload a geospatial file to get started.")