feat: create ChartSelector component with dropdown, delete, and empty state

openspec/changes/multi-chart-management/tasks.md

@@ -28,9 +28,9 @@
 
 ## 5. Chart Selector UI Component
 
-- [ ] 5.1 Create a `ChartSelector` component with dropdown listing all charts (name + created date), positioned in the sidebar between header and file upload
-- [ ] 5.2 Add delete button per chart in the dropdown with confirmation dialog
-- [ ] 5.3 Show "No charts — upload a CSV to get started" placeholder when no charts exist
+- [x] 5.1 Create a `ChartSelector` component with dropdown listing all charts (name + created date), positioned in the sidebar between header and file upload
+- [x] 5.2 Add delete button per chart in the dropdown with confirmation dialog
+- [x] 5.3 Show "No charts — upload a CSV to get started" placeholder when no charts exist
 
 ## 6. Frontend State & Data Flow
 

src/components/ChartSelector.tsx

@@ -0,0 +1,120 @@
+'use client';
+
+import { useState } from 'react';
+import { ChevronDown, Trash2 } from 'lucide-react';
+
+interface Chart {
+  id: number;
+  name: string;
+  created_at: number;
+}
+
+interface ChartSelectorProps {
+  charts: Chart[];
+  activeChartId: number | null;
+  onSelectChart: (chartId: number) => void;
+  onDeleteChart: (chartId: number) => void;
+}
+
+export default function ChartSelector({
+  charts,
+  activeChartId,
+  onSelectChart,
+  onDeleteChart,
+}: ChartSelectorProps) {
+  const [isOpen, setIsOpen] = useState(false);
+  const [confirmDeleteId, setConfirmDeleteId] = useState<number | null>(null);
+
+  const activeChart = charts.find((c) => c.id === activeChartId);
+
+  if (charts.length === 0) {
+    return (
+      <div className="text-sm text-muted-foreground italic">
+        No charts — upload a CSV to get started
+      </div>
+    );
+  }
+
+  const formatDate = (timestamp: number) => {
+    return new Date(timestamp * 1000).toLocaleDateString(undefined, {
+      month: 'short',
+      day: 'numeric',
+      year: 'numeric',
+    });
+  };
+
+  return (
+    <div className="relative">
+      <button
+        onClick={() => setIsOpen(!isOpen)}
+        className="w-full flex items-center justify-between px-3 py-2 text-sm rounded-md border border-border bg-background hover:bg-accent text-foreground"
+      >
+        <span className="truncate">{activeChart?.name || 'Select chart'}</span>
+        <ChevronDown className={`h-4 w-4 ml-2 flex-shrink-0 transition-transform ${isOpen ? 'rotate-180' : ''}`} />
+      </button>
+
+      {isOpen && (
+        <div className="absolute z-50 mt-1 w-full rounded-md border border-border bg-popover shadow-md max-h-64 overflow-y-auto">
+          {charts.map((chart) => (
+            <div
+              key={chart.id}
+              className={`flex items-center justify-between px-3 py-2 text-sm hover:bg-accent cursor-pointer ${
+                chart.id === activeChartId ? 'bg-accent/50' : ''
+              }`}
+            >
+              <div
+                className="flex-1 min-w-0"
+                onClick={() => {
+                  onSelectChart(chart.id);
+                  setIsOpen(false);
+                }}
+              >
+                <div className="truncate text-foreground">{chart.name}</div>
+                <div className="text-xs text-muted-foreground">{formatDate(chart.created_at)}</div>
+              </div>
+              <button
+                onClick={(e) => {
+                  e.stopPropagation();
+                  setConfirmDeleteId(chart.id);
+                }}
+                className="ml-2 p-1 text-muted-foreground hover:text-destructive flex-shrink-0"
+                title="Delete chart"
+              >
+                <Trash2 className="h-3.5 w-3.5" />
+              </button>
+            </div>
+          ))}
+        </div>
+      )}
+
+      {/* Confirmation dialog */}
+      {confirmDeleteId !== null && (
+        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
+          <div className="bg-popover border border-border rounded-lg p-6 max-w-sm mx-4 shadow-lg">
+            <p className="text-sm text-foreground">
+              Delete chart &ldquo;{charts.find((c) => c.id === confirmDeleteId)?.name}&rdquo; and all its candles and annotations? This cannot be undone.
+            </p>
+            <div className="flex justify-end gap-2 mt-4">
+              <button
+                onClick={() => setConfirmDeleteId(null)}
+                className="px-3 py-1.5 text-sm rounded-md border border-border hover:bg-accent text-foreground"
+              >
+                Cancel
+              </button>
+              <button
+                onClick={() => {
+                  onDeleteChart(confirmDeleteId);
+                  setConfirmDeleteId(null);
+                  setIsOpen(false);
+                }}
+                className="px-3 py-1.5 text-sm rounded-md bg-destructive text-destructive-foreground hover:bg-destructive/90"
+              >
+                Delete
+              </button>
+            </div>
+          </div>
+        </div>
+      )}
+    </div>
+  );
+}