import streamlit as st
import pandas as pd
from sqlalchemy import create_engine, text
from sshtunnel import SSHTunnelForwarder
import os
import tempfile
from datetime import datetime, timedelta

# --- Config ---
st.set_page_config(page_title="GPS Viewer", layout="wide")
st.title("🚀 GPS Track on Google Maps")

# --- Secrets ---
SSH_KEY = st.secrets["SSH_KEY"]
SSH_USER = st.secrets["SSH_USER"]
SSH_HOST = st.secrets["DB_HOST"]
REMOTE_BIND_HOST = st.secrets["REMOTE_BIND_HOST"]
LOCAL_BIND_HOST = st.secrets["LOCAL_BIND_HOST"]
MYSQL_USER = st.secrets["MYSQL_USER"]
MYSQL_PASSWORD = st.secrets["MYSQL_PASSWORD"]
MYSQL_DB = st.secrets["DB_NAME"]
MYSQL_PORT = int(st.secrets["MYSQL_PORT"])
GOOGLE_MAPS_API_KEY = st.secrets["GOOGLE_MAPS_API_KEY"]

# --- Write SSH key to temp file ---
with tempfile.NamedTemporaryFile(delete=False, suffix=".pem") as temp_file:
    temp_file.write(SSH_KEY.encode())
    temp_file_path = temp_file.name
os.chmod(temp_file_path, 0o600)

# --- SSH Tunnel ---
@st.cache_resource
def start_ssh_tunnel():
    tunnel = SSHTunnelForwarder(
        (SSH_HOST, 22),
        ssh_username=SSH_USER,
        ssh_pkey=temp_file_path,
        remote_bind_address=(REMOTE_BIND_HOST, MYSQL_PORT),
        local_bind_address=(LOCAL_BIND_HOST, MYSQL_PORT)
    )
    tunnel.start()
    return tunnel

server = start_ssh_tunnel()
if not server.is_active:
    server.start()

# --- SQLAlchemy Engine ---
MYSQL_URL = f"mysql+pymysql://{MYSQL_USER}:{MYSQL_PASSWORD}@{LOCAL_BIND_HOST}:{MYSQL_PORT}/{MYSQL_DB}"
engine = create_engine(MYSQL_URL, pool_pre_ping=True, pool_recycle=3600)

# --- Fetch timestamp range from DB ---
def get_timestamp_range():
    try:
        with engine.connect() as conn:
            result = conn.execute(text("SELECT MIN(timestamp) as min_ts, MAX(timestamp) as max_ts FROM telemetry_data")).fetchone()
            return result[0], result[1]  # min_ts, max_ts
    except Exception as e:
        st.error(f"Error fetching timestamp range: {e}")
        return None, None

min_ts, max_ts = get_timestamp_range()

# --- Time range selection ---
st.sidebar.header("Filter by Time Frame")
if min_ts and max_ts:
    start_datetime = st.sidebar.slider("Start and End Time", min_value=min_ts, max_value=max_ts,
                                        value=(min_ts, max_ts), format="YYYY-MM-DD HH:mm:ss")
    start_ts, end_ts = start_datetime
else:
    start_ts = end_ts = None

# --- Load GPS Data ---
def load_gps_data(from_ts, to_ts):
    try:
        query = text("""
            SELECT latitude, longitude, device_id
            FROM telemetry_data
            WHERE timestamp BETWEEN :from_ts AND :to_ts
            ORDER BY timestamp
        """)
        with engine.connect() as conn:
            df = pd.read_sql(query, conn, params={"from_ts": from_ts, "to_ts": to_ts})
        return df
    except Exception as e:
        st.error(f"Error loading GPS data: {e}")
        return pd.DataFrame()

gps_data = pd.DataFrame()
if start_ts and end_ts:
    gps_data = load_gps_data(start_ts, end_ts)

# --- Display on Google Maps ---
if not gps_data.empty:
    points = gps_data[["latitude", "longitude"]].to_dict(orient="records")
    js_points = ",\n".join([f"{{ lat: {p['latitude']}, lng: {p['longitude']} }}" for p in points])

    st.components.v1.html(f"""
    <div id=\"map\" style=\"height: 80vh; width: 100%;\"></div>
    <div style=\"text-align: center; margin: 10px;\">
      <button onclick=\"startReplay()\">▶️ Start</button>
      <button onclick=\"pauseReplay()\">⏸ Pause</button>
      <button onclick=\"resetReplay()\">🔄 Reset</button>
      <button onclick=\"stepBack()\">⏪ Back</button>
      <button onclick=\"stepForward()\">⏩ Forward</button>
    </div>

    <script src=\"https://maps.googleapis.com/maps/api/js?key={GOOGLE_MAPS_API_KEY}\"></script>
    <script>
      const pathCoords = [{js_points}];
      let map, marker, interval, index = 0, playing = false;

      function initMap() {{
        map = new google.maps.Map(document.getElementById(\"map\"), {{
          zoom: 14,
          center: pathCoords[0],
          mapTypeId: \"roadmap\"
        }});

        new google.maps.Polyline({{
          path: pathCoords,
          geodesic: true,
          strokeColor: \"#FF0000\",
          strokeOpacity: 1.0,
          strokeWeight: 2
        }}).setMap(map);

        marker = new google.maps.Marker({{
          position: pathCoords[0],
          map: map,
          icon: {{
            path: google.maps.SymbolPath.CIRCLE,
            scale: 6,
            fillColor: \"#0000FF\",
            fillOpacity: 1.0,
            strokeWeight: 1
          }}
        }});
      }}

      function updateMarker() {{
        marker.setPosition(pathCoords[index]);
        map.panTo(pathCoords[index]);
      }}

      function playStep() {{
        if (index < pathCoords.length - 1) {{
          index++;
          updateMarker();
        }} else {{
          clearInterval(interval);
          playing = false;
        }}
      }}

      function startReplay() {{
        if (!playing) {{
          interval = setInterval(playStep, 200);
          playing = true;
        }}
      }}

      function pauseReplay() {{
        clearInterval(interval);
        playing = false;
      }}

      function resetReplay() {{
        pauseReplay();
        index = 0;
        updateMarker();
      }}

      function stepBack() {{
        pauseReplay();
        if (index > 0) {{
          index--;
          updateMarker();
        }}
      }}

      function stepForward() {{
        pauseReplay();
        if (index < pathCoords.length - 1) {{
          index++;
          updateMarker();
        }}
      }}

      window.onload = initMap;
    </script>
    """, height=750)

    st.subheader("📊 Telemetry Data")
    st.dataframe(gps_data[["device_id"]])
else:
    st.info("No GPS data available for selected time frame.")