{# Widget partial: Chart.js chart
   Rendered server-side as HTML fragment for HTMX loading.
   Expects: widget (dict), data (dict with columns/rows), widget_id (int), chart_config (dict)
#}
{% from "components/feedback.html" import empty_state %}
{% if error %}
<div class="flex items-center justify-center h-full text-xs" style="color:var(--red)">
    <span>{{ error }}</span>
</div>
{% elif data and data.columns %}
<div class="bi-chart-container">
    <canvas id="widget-chart-{{ widget_id }}"></canvas>
</div>
<script>
window.biRenderChart({{ widget_id }}, {{ chart_config | tojson }});
</script>
{% else %}
<div style="height:100%;display:flex;align-items:center;justify-content:center;color:var(--fg-3);opacity:0.4">
    <p>No data</p>
</div>
{% endif %}