"""Graphs routes — interactive charts via Plotly.js.

Replaces Java I2P's JRobin server-side PNG rendering with
client-side interactive charts.

Ported from net.i2p.router.web.helpers.GraphHelper / SummaryListener.
"""

from __future__ import annotations

from flask import Blueprint, render_template, current_app, jsonify

bp = Blueprint("graphs", __name__)


@bp.route("/graphs")
def graphs():
    """Graphs overview page with Plotly.js charts."""
    return render_template("graphs.html")


@bp.route("/graphs/data/<stat_name>")
def graph_data(stat_name: str):
    """JSON endpoint for chart data."""
    stats = current_app.config.get("STATS_COLLECTOR")
    if stats is None:
        return jsonify({"labels": [], "values": []})
    samples = stats.get(stat_name)
    return jsonify({
        "labels": [s.timestamp for s in samples],
        "values": [s.value for s in samples],
    })