table import works now

components/Inventory.tsx

@@ -12,6 +12,7 @@ import {
   Camera, Sparkles, Mail, Search, Plus, AlertTriangle,
   ChevronDown, ChevronUp, Loader2, Trash2, FlaskConical,
   Table2, FileDown, FileSpreadsheet, Upload, ArrowRight,
+  CheckSquare,
 } from "lucide-react";
 import {
   Dialog, DialogContent, DialogHeader, DialogTitle, DialogTrigger,
@@ -19,6 +20,7 @@ import {
 import {
   Select, SelectContent, SelectItem, SelectTrigger, SelectValue,
 } from "./ui/select";
+import { Checkbox } from "./ui/checkbox";
 
 // ── constants ──────────────────────────────────────────────────────────────
 
@@ -130,6 +132,11 @@ export function Inventory() {
   const [searchQuery, setSearchQuery] = useState("");
   const [expandedId, setExpandedId] = useState<string | null>(null);
 
+  // selection mode
+  const [isSelectionMode, setIsSelectionMode] = useState(false);
+  const [selectedIds, setSelectedIds] = useState<Set<string>>(new Set());
+  const [isDeleting, setIsDeleting] = useState(false);
+
   // add/edit dialog
   const [dialogOpen, setDialogOpen] = useState(false);
   const [editingItem, setEditingItem] = useState<ChemicalInventory | null>(null);
@@ -144,9 +151,12 @@ export function Inventory() {
   // import dialog
   const [importOpen, setImportOpen] = useState(false);
   const [importStep, setImportStep] = useState<"upload" | "map" | "result">("upload");
+  const [fallbackReason, setFallbackReason] = useState("");
   const [importHeaders, setImportHeaders] = useState<string[]>([]);
   const [importRows, setImportRows] = useState<string[][]>([]);
-  const [columnMapping, setColumnMapping] = useState<Record<string, ImportColumnMapping>>({});
+  const [columnMapping, setColumnMapping] = useState<Record<string, keyof ChemicalInventory | "__skip__">>({});
+  const [columnMatchInfo, setColumnMatchInfo] = useState<Record<string, { confidence: number; reason: string }>>({});
+  const [isMatching, setIsMatching] = useState(false);
   const [importResult, setImportResult] = useState<{ imported: number; errors: string[] } | null>(null);
   const [isImporting, setIsImporting] = useState(false);
   const [importError, setImportError] = useState("");
@@ -192,25 +202,15 @@ export function Inventory() {
   }
 
   async function handleSave() {
-    const required: (keyof ChemicalInventory)[] = [
-      "piFirstName","physicalState","chemicalName","bldgCode","lab",
-      "storageLocation","storageDevice","numberOfContainers","amountPerContainer",
-      "unitOfMeasure","casNumber",
-    ];
-    const missing = required.filter(k => !form[k]);
-    if (missing.length) {
-      setFormError("Please fill in all required fields.");
-      return;
-    }
-    if (!validateCAS(String(form.casNumber || ""))) {
+    if (form.casNumber && !validateCAS(String(form.casNumber))) {
       setFormError("CAS # must be in the format ##-##-# (e.g. 67-56-1).");
       return;
     }
-    if (!validateNumber(form.numberOfContainers, { min: 1, integer: true })) {
+    if (form.numberOfContainers && !validateNumber(form.numberOfContainers, { min: 1, integer: true })) {
       setFormError("# of containers must be a whole number of 1 or more.");
       return;
     }
-    if (!validateNumber(form.amountPerContainer, { min: 0 })) {
+    if (form.amountPerContainer && !validateNumber(form.amountPerContainer, { min: 0 })) {
       setFormError("Amount per container must be a number.");
       return;
     }
@@ -249,6 +249,31 @@ export function Inventory() {
     await chemicalsApi.remove(id);
     setInventory(inv => inv.filter(c => c.id !== id));
     if (expandedId === id) setExpandedId(null);
+    setSelectedIds(prev => {
+      const next = new Set(prev);
+      next.delete(id);
+      return next;
+    });
+  }
+
+  async function handleDeleteSelected() {
+    if (selectedIds.size === 0) return;
+    if (!confirm(`Remove ${selectedIds.size} selected chemical(s) from inventory?`)) return;
+    
+    setIsDeleting(true);
+    try {
+      const ids = Array.from(selectedIds);
+      await chemicalsApi.bulkRemove(ids);
+      setInventory(inv => inv.filter(c => !selectedIds.has(c.id)));
+      setExpandedId(null);
+      setSelectedIds(new Set());
+      setIsSelectionMode(false);
+    } catch (err) {
+      console.error("Failed to delete selected:", err);
+      alert("Failed to delete some or all items. Please refresh and try again.");
+    } finally {
+      setIsDeleting(false);
+    }
   }
 
   // ── scan helpers ────────────────────────────────────────────────────────
@@ -305,7 +330,10 @@ export function Inventory() {
 
   function handleDownloadCSV() {
     const headers = TABLE_COLUMNS.map(c => c.label);
-    const rows = filtered.map(item =>
+    const itemsToExport = isSelectionMode && selectedIds.size > 0 
+      ? filtered.filter(item => selectedIds.has(item.id)) 
+      : filtered;
+    const rows = itemsToExport.map(item =>
       TABLE_COLUMNS.map(c => String(item[c.key] ?? ""))
     );
     const csv = [headers, ...rows]
@@ -324,7 +352,10 @@ export function Inventory() {
     const wb = new ExcelJS.Workbook();
     const ws = wb.addWorksheet("Chemical Inventory");
     ws.addRow(TABLE_COLUMNS.map(c => c.label));
-    filtered.forEach(item => ws.addRow(TABLE_COLUMNS.map(c => item[c.key] ?? "")));
+    const itemsToExport = isSelectionMode && selectedIds.size > 0 
+      ? filtered.filter(item => selectedIds.has(item.id)) 
+      : filtered;
+    itemsToExport.forEach(item => ws.addRow(TABLE_COLUMNS.map(c => item[c.key] ?? "")));
     const buffer = await wb.xlsx.writeBuffer();
     const blob = new Blob([buffer], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });
     const url = URL.createObjectURL(blob);
@@ -371,8 +402,10 @@ export function Inventory() {
     setImportHeaders([]);
     setImportRows([]);
     setColumnMapping({});
+    setColumnMatchInfo({});
     setImportResult(null);
     setImportError("");
+    setFallbackReason("");
     setImportOpen(true);
   }
 
@@ -418,7 +451,15 @@ export function Inventory() {
         if (!ws) throw new Error("No worksheets found in this file.");
         allRows = [];
         ws.eachRow(row => {
-          allRows.push((row.values as ExcelJS.CellValue[]).slice(1).map(v => String(v ?? "")));
+          allRows.push((row.values as ExcelJS.CellValue[]).slice(1).map(v => {
+            if (v instanceof Date) {
+              return v.toISOString().split('T')[0];
+            }
+            if (v && typeof v === 'object' && 'result' in v && v.result instanceof Date) {
+              return v.result.toISOString().split('T')[0];
+            }
+            return String(v ?? "");
+          }));
         });
         console.log("[import] parsed rows:", allRows.length);
       }
@@ -432,11 +473,44 @@ export function Inventory() {
       console.log("[import] headers:", headers, "data rows:", dataRows.length);
       setImportHeaders(headers);
       setImportRows(dataRows);
-      const mapping: Record<string, ImportColumnMapping> = {};
-      for (const h of headers) mapping[h] = fuzzyMatchColumn(h);
-      setColumnMapping(mapping);
-      console.log("[import] advancing to map step");
+      // Seed every header to skip while we wait for the semantic matcher.
+      const seeded: Record<string, keyof ChemicalInventory | "__skip__"> = {};
+      for (const h of headers) seeded[h] = "__skip__";
+      setColumnMapping(seeded);
+      setColumnMatchInfo({});
       setImportStep("map");
+
+      // Run the server-side semantic matcher: Gemini API
+      setIsMatching(true);
+      try {
+        const sampleRows = dataRows.slice(0, 12);
+        const result = await chemicalsApi.columnMatch(headers, sampleRows);
+        const validKeys = new Set(TABLE_COLUMNS.map(c => c.key as string));
+        const next: Record<string, keyof ChemicalInventory | "__skip__"> = { ...seeded };
+        const info: Record<string, { confidence: number; reason: string }> = {};
+        for (const m of result.mappings) {
+          const key = m.key === "__skip__" || validKeys.has(m.key)
+            ? (m.key as keyof ChemicalInventory | "__skip__")
+            : "__skip__";
+          next[m.header] = key;
+          info[m.header] = { confidence: m.confidence, reason: m.reason };
+        }
+        setColumnMapping(next);
+        setColumnMatchInfo(info);
+      } catch (matchErr) {
+        console.error("[import] semantic match failed:", matchErr);
+        setFallbackReason((matchErr as Error).message);
+        const mapping: Record<string, keyof ChemicalInventory | "__skip__"> = {};
+        const info: Record<string, { confidence: number; reason: string }> = {};
+        for (const h of headers) {
+           mapping[h] = fuzzyMatchColumn(h);
+           info[h] = { confidence: 0.6, reason: "Used fuzzy matching fallback." };
+        }
+        setColumnMapping(mapping);
+        setColumnMatchInfo(info);
+      } finally {
+        setIsMatching(false);
+      }
     } catch (err) {
       console.error("[import] error:", err);
       setImportError(`Could not read file: ${(err as Error).message}`);
@@ -480,11 +554,32 @@ export function Inventory() {
 
   const lowStockCount = inventory.filter(c => c.percentageFull != null && c.percentageFull < 20).length;
 
+  const isMissingKeyInfo = (c: ChemicalInventory) => 
+    !c.piFirstName || !c.physicalState || !c.chemicalName || !c.bldgCode || !c.lab || 
+    !c.storageLocation || !c.storageDevice || !c.numberOfContainers || !c.amountPerContainer || 
+    !c.unitOfMeasure || !c.casNumber;
+
+  const missingInfoCount = inventory.filter(isMissingKeyInfo).length;
+
   // ── render ───────────────────────────────────────────────────────────────
 
   return (
     <div className="p-6 max-w-5xl mx-auto">
 
+      {missingInfoCount > 0 && (
+        <Card className="mb-4 p-4 bg-amber-50 border-amber-200">
+          <div className="flex items-start gap-3">
+            <AlertTriangle className="w-5 h-5 text-amber-600 shrink-0 mt-0.5" />
+            <div>
+              <p className="text-sm font-medium text-amber-800">Missing Key Information</p>
+              <p className="text-sm text-amber-700">
+                You have {missingInfoCount} {missingInfoCount === 1 ? "item" : "items"} missing important fields. Please review the highlighted items below and update them.
+              </p>
+            </div>
+          </div>
+        </Card>
+      )}
+
       {/* Header */}
       <div className="flex items-center justify-between mb-4">
         <div>
@@ -638,66 +733,144 @@ export function Inventory() {
             </div>
           )}
 
-          {importStep === "map" && (
-            <div className="space-y-4 mt-2">
-              <p className="text-sm text-muted-foreground">
-                Review the column mapping below. Adjust any mismatches before importing{" "}
-                <span className="font-medium text-foreground">{importRows.length} row{importRows.length !== 1 ? "s" : ""}</span>.
-              </p>
-              <div className="border border-border rounded-lg overflow-hidden">
-                <table className="w-full text-sm">
-                  <thead className="bg-muted/50">
-                    <tr>
-                      <th className="text-left px-3 py-2 text-muted-foreground font-medium">File Column</th>
-                      <th className="text-left px-3 py-2 text-muted-foreground font-medium w-8"></th>
-                      <th className="text-left px-3 py-2 text-muted-foreground font-medium">Maps To</th>
-                      <th className="text-left px-3 py-2 text-muted-foreground font-medium">Sample</th>
-                    </tr>
-                  </thead>
-                  <tbody>
-                    {importHeaders.map((header, idx) => (
-                      <tr key={header} className="border-t border-border">
-                        <td className="px-3 py-2 text-foreground font-mono text-xs">{header}</td>
-                        <td className="px-1 py-2 text-muted-foreground">
-                          <ArrowRight className="w-3 h-3" />
-                        </td>
-                        <td className="px-3 py-2">
-                          <Select
-                            value={columnMapping[header] ?? ""}
-                            onValueChange={v => setColumnMapping(m => ({ ...m, [header]: v as ImportColumnMapping }))}
-                          >
-                            <SelectTrigger className="h-7 text-xs w-48">
-                              <SelectValue placeholder="— skip —" />
-                            </SelectTrigger>
-                            <SelectContent>
-                              <SelectItem value="__skip__">— skip —</SelectItem>
-                              {TABLE_COLUMNS.map(col => (
-                                <SelectItem key={col.key} value={col.key}>{col.label}</SelectItem>
-                              ))}
-                            </SelectContent>
-                          </Select>
-                        </td>
-                        <td className="px-3 py-2 text-muted-foreground text-xs truncate max-w-[120px]">
-                          {importRows[0]?.[idx] ?? ""}
-                        </td>
+          {importStep === "map" && (() => {
+            // Compute which target keys are claimed by more than one source header.
+            const targetCounts = new Map<string, string[]>();
+            for (const h of importHeaders) {
+              const k = columnMapping[h];
+              if (!k || k === "__skip__") continue;
+              const list = targetCounts.get(k) ?? [];
+              list.push(h);
+              targetCounts.set(k, list);
+            }
+            const duplicateTargets = new Map<string, string[]>(
+              Array.from(targetCounts.entries()).filter(([, hs]) => hs.length > 1),
+            );
+            const conflictHeaders = new Set<string>();
+            for (const hs of duplicateTargets.values()) for (const h of hs) conflictHeaders.add(h);
+            const labelByKey = new Map(TABLE_COLUMNS.map(c => [c.key as string, c.label]));
+            const blockImport = duplicateTargets.size > 0 || isMatching;
+
+            if (isMatching) {
+              return (
+                <div className="py-12 flex flex-col items-center justify-center space-y-4">
+                  <Loader2 className="w-10 h-10 text-primary animate-spin" />
+                  <p className="text-foreground font-medium">Matching columns with AI...</p>
+                  <p className="text-muted-foreground text-sm">Please wait while Gemini analyzes your data.</p>
+                </div>
+              );
+            }
+
+            return (
+              <div className="space-y-4 mt-2">
+                {fallbackReason && (
+                  <div className="rounded-lg border border-amber-300 bg-amber-50 p-3 space-y-1">
+                    <p className="text-sm font-medium text-amber-800 flex items-center gap-1">
+                      <AlertTriangle className="w-4 h-4" /> Gemini reasoning failed
+                    </p>
+                    <p className="text-xs text-amber-700">
+                      Error: {fallbackReason}. Used fuzzy matching instead. Please verify the mappings.
+                    </p>
+                  </div>
+                )}
+                <p className="text-sm text-muted-foreground">
+                  Review the column mapping below. Adjust any mismatches before importing{" "}
+                  <span className="font-medium text-foreground">{importRows.length} row{importRows.length !== 1 ? "s" : ""}</span>.
+                </p>
+
+                {duplicateTargets.size > 0 && (
+                  <div className="rounded-lg border border-red-300 bg-red-50 p-3 space-y-1">
+                    <p className="text-sm font-medium text-red-700 flex items-center gap-1">
+                      <AlertTriangle className="w-4 h-4" /> Each inventory field can only be filled by one file column.
+                    </p>
+                    <ul className="text-xs text-red-700 list-disc pl-5 space-y-0.5">
+                      {Array.from(duplicateTargets.entries()).map(([key, hs]) => (
+                        <li key={key}>
+                          <span className="font-medium">{labelByKey.get(key) ?? key}</span> is mapped from:{" "}
+                          {hs.map(h => `“${h}”`).join(", ")} — pick one and set the others to “— skip —”.
+                        </li>
+                      ))}
+                    </ul>
+                  </div>
+                )}
+
+                <div className="border border-border rounded-lg overflow-hidden">
+                  <table className="w-full text-sm">
+                    <thead className="bg-muted/50">
+                      <tr>
+                        <th className="text-left px-3 py-2 text-muted-foreground font-medium">File Column</th>
+                        <th className="text-left px-3 py-2 text-muted-foreground font-medium w-8"></th>
+                        <th className="text-left px-3 py-2 text-muted-foreground font-medium">Maps To</th>
+                        <th className="text-left px-3 py-2 text-muted-foreground font-medium">Sample</th>
                       </tr>
-                    ))}
-                  </tbody>
-                </table>
+                    </thead>
+                    <tbody>
+                      {importHeaders.map((header, idx) => {
+                        const isConflict = conflictHeaders.has(header);
+                        const info = columnMatchInfo[header];
+                        const lowConfidence = info && info.confidence > 0 && info.confidence < 0.5
+                          && columnMapping[header] !== "__skip__";
+                        return (
+                          <tr
+                            key={header}
+                            className={`border-t border-border ${isConflict ? "bg-red-50" : ""}`}
+                          >
+                            <td className="px-3 py-2 text-foreground font-mono text-xs">{header}</td>
+                            <td className="px-1 py-2 text-muted-foreground">
+                              <ArrowRight className="w-3 h-3" />
+                            </td>
+                            <td className="px-3 py-2">
+                              <Select
+                                value={columnMapping[header] ?? "__skip__"}
+                                onValueChange={v => setColumnMapping(m => ({ ...m, [header]: v as keyof ChemicalInventory | "__skip__" }))}
+                              >
+                                <SelectTrigger
+                                  className={`h-7 text-xs w-48 ${isConflict ? "border-red-400 ring-1 ring-red-300" : ""}`}
+                                  title={info?.reason || undefined}
+                                >
+                                  <SelectValue placeholder="— skip —" />
+                                </SelectTrigger>
+                                <SelectContent>
+                                  <SelectItem value="__skip__">— skip —</SelectItem>
+                                  {TABLE_COLUMNS.map(col => (
+                                    <SelectItem key={col.key} value={col.key}>{col.label}</SelectItem>
+                                  ))}
+                                </SelectContent>
+                              </Select>
+                              {lowConfidence && !isConflict && (
+                                <p className="text-[10px] text-amber-600 mt-0.5">
+                                  Low confidence — please verify.
+                                </p>
+                              )}
+                            </td>
+                            <td className="px-3 py-2 text-muted-foreground text-xs truncate max-w-[120px]">
+                              {importRows[0]?.[idx] ?? ""}
+                            </td>
+                          </tr>
+                        );
+                      })}
+                    </tbody>
+                  </table>
+                </div>
+
+                <div className="flex gap-2 pt-1">
+                  <Button
+                    className="flex-1 bg-primary hover:bg-primary/90 gap-2"
+                    onClick={handleImportConfirm}
+                    disabled={isImporting || blockImport}
+                  >
+                    {isImporting ? <Loader2 className="w-4 h-4 animate-spin" /> : <Upload className="w-4 h-4" />}
+                    {isImporting
+                      ? "Importing…"
+                      : duplicateTargets.size > 0
+                        ? "Resolve duplicate mappings to import"
+                        : `Import ${importRows.length} row${importRows.length !== 1 ? "s" : ""}`}
+                  </Button>
+                  <Button variant="outline" onClick={() => setImportStep("upload")}>Back</Button>
+                </div>
               </div>
-              <div className="flex gap-2 pt-1">
-                <Button
-                  className="flex-1 bg-primary hover:bg-primary/90 gap-2"
-                  onClick={handleImportConfirm}
-                  disabled={isImporting}
-                >
-                  {isImporting ? <Loader2 className="w-4 h-4 animate-spin" /> : <Upload className="w-4 h-4" />}
-                  {isImporting ? "Importing…" : `Import ${importRows.length} row${importRows.length !== 1 ? "s" : ""}`}
-                </Button>
-                <Button variant="outline" onClick={() => setImportStep("upload")}>Back</Button>
-              </div>
-            </div>
-          )}
+            );
+          })()}
 
           {importStep === "result" && importResult && (
             <div className="space-y-4 mt-2">
@@ -741,33 +914,76 @@ export function Inventory() {
         </div>
       </Card>
 
-      {/* Search + stats */}
-      <div className="flex items-center gap-3 mb-5">
-        <div className="relative flex-1">
-          <Search className="absolute left-3 top-1/2 -translate-y-1/2 text-muted-foreground w-4 h-4" />
-          <Input
-            placeholder="Search by name, CAS, lab, or location…"
-            className="pl-9"
-            value={searchQuery}
-            onChange={e => setSearchQuery(e.target.value)}
-          />
+      {/* Search + stats / Selection Action Bar */}
+      {isSelectionMode ? (
+        <Card className="mb-5 p-3 flex flex-col sm:flex-row items-start sm:items-center justify-between gap-4 border-primary/20 bg-primary/5">
+          <div className="flex items-center gap-4 pl-1">
+            <div className="flex items-center gap-2">
+              <Checkbox 
+                id="select-all" 
+                checked={filtered.length > 0 && selectedIds.size === filtered.length}
+                onCheckedChange={(checked) => {
+                  if (checked) {
+                    setSelectedIds(new Set(filtered.map(c => c.id)));
+                  } else {
+                    setSelectedIds(new Set());
+                  }
+                }}
+              />
+              <Label htmlFor="select-all" className="cursor-pointer">Select All</Label>
+            </div>
+            <span className="text-sm font-medium text-primary">
+              {selectedIds.size} selected
+            </span>
+          </div>
+          <div className="flex items-center gap-2 flex-wrap">
+            <Button size="sm" variant="ghost" onClick={() => { setIsSelectionMode(false); setSelectedIds(new Set()); }}>
+              Cancel
+            </Button>
+            <Button size="sm" variant="outline" className="gap-1.5" onClick={handleDownloadCSV} disabled={selectedIds.size === 0}>
+              <FileDown className="w-4 h-4" /> CSV
+            </Button>
+            <Button size="sm" variant="outline" className="gap-1.5" onClick={handleDownloadExcel} disabled={selectedIds.size === 0}>
+              <FileSpreadsheet className="w-4 h-4" /> Excel
+            </Button>
+            <Button size="sm" variant="destructive" className="gap-1.5" onClick={handleDeleteSelected} disabled={selectedIds.size === 0 || isDeleting}>
+              {isDeleting ? <Loader2 className="w-4 h-4 animate-spin" /> : <Trash2 className="w-4 h-4" />} 
+              {isDeleting ? "Deleting..." : "Delete Selected"}
+            </Button>
+          </div>
+        </Card>
+      ) : (
+        <div className="flex items-center gap-3 mb-5">
+          <div className="relative flex-1">
+            <Search className="absolute left-3 top-1/2 -translate-y-1/2 text-muted-foreground w-4 h-4" />
+            <Input
+              placeholder="Search by name, CAS, lab, or location…"
+              className="pl-9"
+              value={searchQuery}
+              onChange={e => setSearchQuery(e.target.value)}
+            />
+          </div>
+          <div className="flex items-center gap-2 shrink-0 text-sm text-muted-foreground">
+            <FlaskConical className="w-4 h-4 text-[#5a9584]" />
+            <span className="hidden sm:inline">{inventory.length} chemicals</span>
+            {lowStockCount > 0 && (
+              <>
+                <span className="text-border hidden sm:inline">·</span>
+                <AlertTriangle className="w-4 h-4 text-amber-500" />
+                <span className="text-amber-600 hidden sm:inline">{lowStockCount} low stock</span>
+              </>
+            )}
+            <span className="text-border">·</span>
+            <Button variant="ghost" size="sm" className="gap-1.5 h-7 px-2 text-muted-foreground bg-background hover:bg-background/80 hover:text-foreground rounded-md" onClick={() => setIsSelectionMode(true)}>
+              <CheckSquare className="w-3.5 h-3.5" /> Select
+            </Button>
+            <span className="text-border">·</span>
+            <Button variant="ghost" size="sm" className="gap-1.5 h-7 px-2 text-muted-foreground bg-background hover:bg-background/80 hover:text-foreground rounded-md" onClick={() => setTableViewOpen(true)}>
+              <Table2 className="w-3.5 h-3.5" /> Table
+            </Button>
+          </div>
         </div>
-        <div className="flex items-center gap-2 shrink-0 text-sm text-muted-foreground">
-          <FlaskConical className="w-4 h-4 text-[#5a9584]" />
-          <span>{inventory.length} chemicals</span>
-          {lowStockCount > 0 && (
-            <>
-              <span className="text-border">·</span>
-              <AlertTriangle className="w-4 h-4 text-amber-500" />
-              <span className="text-amber-600">{lowStockCount} low stock</span>
-            </>
-          )}
-          <span className="text-border">·</span>
-          <Button variant="ghost" size="sm" className="gap-1.5 h-7 px-2 text-muted-foreground bg-background hover:bg-background/80 hover:text-foreground rounded-md" onClick={() => setTableViewOpen(true)}>
-            <Table2 className="w-3.5 h-3.5" /> View / Export Table
-          </Button>
-        </div>
-      </div>
+      )}
 
       {/* List */}
       {isLoading ? (
@@ -788,15 +1004,39 @@ export function Inventory() {
             const expired = days !== null && days < 0;
             const expiringSoon = days !== null && days >= 0 && days <= 30;
             const lowStock = item.percentageFull != null && item.percentageFull < 20;
+            const missingInfo = isMissingKeyInfo(item);
+
+            const isSelected = selectedIds.has(item.id);
 
             return (
-              <Card key={item.id} className={`overflow-hidden transition-shadow ${isExpanded ? "shadow-md" : "hover:shadow-sm"}`}>
+              <Card key={item.id} className={`overflow-hidden transition-shadow ${isExpanded ? "shadow-md" : "hover:shadow-sm"} ${missingInfo && !isExpanded ? "border-amber-300 bg-amber-50/30" : ""} ${isSelected ? "border-primary/50 bg-primary/5" : ""}`}>
                 {/* Summary row */}
-                <button
-                  className="w-full text-left px-5 py-4 flex items-center gap-4"
-                  onClick={() => setExpandedId(isExpanded ? null : item.id)}
-                >
-                  {/* Name + state */}
+                <div className="flex items-stretch w-full">
+                  {isSelectionMode && (
+                    <div 
+                      className="flex items-center justify-center px-4 cursor-pointer hover:bg-muted/50 border-r border-border/50"
+                      onClick={(e) => {
+                        e.stopPropagation();
+                        setSelectedIds(prev => {
+                          const next = new Set(prev);
+                          if (next.has(item.id)) next.delete(item.id);
+                          else next.add(item.id);
+                          return next;
+                        });
+                      }}
+                    >
+                      <Checkbox 
+                        checked={isSelected} 
+                        className="w-5 h-5 pointer-events-none" 
+                        onCheckedChange={() => {}} // handled by parent div
+                      />
+                    </div>
+                  )}
+                  <button
+                    className="flex-1 text-left px-5 py-4 flex items-center gap-4"
+                    onClick={() => setExpandedId(isExpanded ? null : item.id)}
+                  >
+                    {/* Name + state */}
                   <div className="flex-1 min-w-0">
                     <div className="flex items-center gap-2 flex-wrap">
                       <span className="font-medium text-foreground">{item.chemicalName}</span>
@@ -804,6 +1044,7 @@ export function Inventory() {
                       {expired && <Badge className="bg-red-100 text-red-700 border-red-200 border text-xs py-0">Expired</Badge>}
                       {expiringSoon && !expired && <Badge className="bg-amber-100 text-amber-700 border-amber-200 border text-xs py-0">Exp. {days}d</Badge>}
                       {lowStock && <Badge className="bg-red-100 text-red-700 border-red-200 border text-xs py-0">Low stock</Badge>}
+                      {missingInfo && <Badge className="bg-amber-100 text-amber-800 border-amber-300 border text-xs py-0 gap-1"><AlertTriangle className="w-3 h-3" /> Missing info</Badge>}
                     </div>
                     <p className="text-sm text-muted-foreground mt-0.5">{item.lab} · {item.storageLocation || "—"}</p>
                   </div>
@@ -827,7 +1068,8 @@ export function Inventory() {
                   {isExpanded
                     ? <ChevronUp className="w-4 h-4 text-muted-foreground shrink-0" />
                     : <ChevronDown className="w-4 h-4 text-muted-foreground shrink-0" />}
-                </button>
+                  </button>
+                </div>
 
                 {/* Expanded detail */}
                 {isExpanded && (

lib/api.ts

@@ -35,11 +35,23 @@ export const chemicalsApi = {
   remove: (id: string): Promise<void> =>
     apiFetch(`/api/chemicals/${id}`, { method: 'DELETE' }).then(() => undefined),
 
+  bulkRemove: (ids: string[]): Promise<void> =>
+    apiFetch('/api/chemicals/bulk-delete', { 
+      method: 'POST', 
+      body: JSON.stringify({ ids }) 
+    }).then(() => undefined),
+
   import: (rows: Partial<ChemicalInventory>[]): Promise<{ imported: number; errors: string[] }> =>
     apiFetch('/api/chemicals/import', {
       method: 'POST',
       body: JSON.stringify({ rows }),
     }).then(r => r.json()),
+
+  columnMatch: (headers: string[], sampleRows: string[][]): Promise<{ mappings: { header: string; key: string; confidence: number; reason: string }[] }> =>
+    apiFetch('/api/chemicals/column-match', {
+      method: 'POST',
+      body: JSON.stringify({ headers, sampleRows }),
+    }).then(r => r.json()),
 };
 
 export const protocolsApi = {

server/package.json

@@ -10,6 +10,7 @@
   },
   "dependencies": {
     "@better-auth/kysely-adapter": "^1.5.6",
+    "@google/generative-ai": "^0.24.1",
     "@node-rs/argon2": "^2.0.2",
     "better-auth": "^1.5.5",
     "cors": "^2.8.5",

server/src/auth/email.ts

@@ -2,10 +2,10 @@ import FormData from 'form-data';
 import Mailgun from 'mailgun.js';
 
 const mailgun = new (Mailgun as any)(FormData);
-const mg = mailgun.client({
+const mg = process.env.MAILGUN_API_KEY ? mailgun.client({
   username: 'api',
-  key: process.env.MAILGUN_API_KEY || '',
-});
+  key: process.env.MAILGUN_API_KEY,
+}) : null;
 
 const DOMAIN = process.env.MAILGUN_DOMAIN || 'sandbox06aa4efa8cc342878b7470a7c9113df3.mailgun.org';
 const FROM = process.env.FROM_EMAIL || `LabWise <postmaster@${DOMAIN}>`;
@@ -19,6 +19,10 @@ export async function sendEmail({
   subject: string;
   html: string;
 }) {
+  if (!mg) {
+    console.warn('[auth] MAILGUN_API_KEY is not set. Email not sent:', subject);
+    return;
+  }
   await mg.messages.create(DOMAIN, {
     from: FROM,
     to: [to],

server/src/db/schema.sql

@@ -128,3 +128,16 @@ ALTER TABLE user_profile ALTER COLUMN lab DROP NOT NULL;
 
 -- Allow name to be cleared (set to null).
 ALTER TABLE "user" ALTER COLUMN "name" DROP NOT NULL;
+
+-- Allow incomplete chemical imports.
+ALTER TABLE chemicals ALTER COLUMN pi_first_name DROP NOT NULL;
+ALTER TABLE chemicals ALTER COLUMN physical_state DROP NOT NULL;
+ALTER TABLE chemicals ALTER COLUMN chemical_name DROP NOT NULL;
+ALTER TABLE chemicals ALTER COLUMN bldg_code DROP NOT NULL;
+ALTER TABLE chemicals ALTER COLUMN lab DROP NOT NULL;
+ALTER TABLE chemicals ALTER COLUMN storage_location DROP NOT NULL;
+ALTER TABLE chemicals ALTER COLUMN storage_device DROP NOT NULL;
+ALTER TABLE chemicals ALTER COLUMN number_of_containers DROP NOT NULL;
+ALTER TABLE chemicals ALTER COLUMN amount_per_container DROP NOT NULL;
+ALTER TABLE chemicals ALTER COLUMN unit_of_measure DROP NOT NULL;
+ALTER TABLE chemicals ALTER COLUMN cas_number DROP NOT NULL;

server/src/routes/chemicals.ts

@@ -1,6 +1,7 @@
 import { Router } from 'express';
 import { pool } from '../db/pool.js';
 import { requireAuth } from '../auth/middleware.js';
+import { GoogleGenerativeAI, SchemaType } from '@google/generative-ai';
 
 const router = Router();
 router.use(requireAuth);
@@ -42,9 +43,9 @@ router.post('/', async (req, res) => {
         $13,$14,$15,$16,$17,$18,$19,$20,$21,$22,$23,$24,$25
       ) RETURNING *, percentage_full::float AS percentage_full, expiration_date::text AS expiration_date`,
       [
-        req.user!.id, b.piFirstName, b.physicalState, b.chemicalName, b.bldgCode, b.lab,
-        b.storageLocation, b.storageDevice, b.numberOfContainers, b.amountPerContainer,
-        b.unitOfMeasure, b.casNumber,
+        req.user!.id, b.piFirstName || null, b.physicalState || null, b.chemicalName || null, b.bldgCode || null, b.lab || null,
+        b.storageLocation || null, b.storageDevice || null, b.numberOfContainers || null, b.amountPerContainer || null,
+        b.unitOfMeasure || null, b.casNumber || null,
         b.chemicalFormula || null, b.molecularWeight || null, b.vendor || null,
         b.catalogNumber || null, b.lotNumber || null,
         b.expirationDate || null, b.concentration || null,
@@ -122,6 +123,25 @@ router.post('/import', async (req, res) => {
   res.json({ imported, errors });
 });
 
+// POST /api/chemicals/bulk-delete
+router.post('/bulk-delete', async (req, res) => {
+  try {
+    const { ids } = req.body;
+    if (!Array.isArray(ids) || ids.length === 0) {
+      return res.status(400).json({ error: 'No IDs provided' });
+    }
+    
+    await pool.query(
+      'DELETE FROM chemicals WHERE id = ANY($1) AND user_id = $2',
+      [ids, req.user!.id]
+    );
+    res.status(204).end();
+  } catch (err) {
+    console.error(err);
+    res.status(500).json({ error: 'Internal server error' });
+  }
+});
+
 // DELETE /api/chemicals/:id
 router.delete('/:id', async (req, res) => {
   try {
@@ -143,4 +163,118 @@ function snakeToCamel(row: Record<string, unknown>): Record<string, unknown> {
   );
 }
 
+// POST /api/chemicals/column-match
+router.post('/column-match', async (req, res) => {
+  try {
+    const { headers, sampleRows } = req.body;
+    if (!headers || !Array.isArray(headers)) {
+      return res.status(400).json({ error: 'Headers must be an array' });
+    }
+
+    const apiKey = process.env.GEMINI_API_KEY;
+    if (!apiKey) {
+      // Graceful fallback or error
+      return res.status(500).json({ error: 'GEMINI_API_KEY is not configured.' });
+    }
+
+    const genAI = new GoogleGenerativeAI(apiKey);
+    const model = genAI.getGenerativeModel({ model: 'gemini-2.5-flash' });
+
+    const canonicalColumns = [
+      { label: "PI First Name", key: "piFirstName" },
+      { label: "Physical State", key: "physicalState" },
+      { label: "Chemical Name", key: "chemicalName" },
+      { label: "Bldg Code", key: "bldgCode" },
+      { label: "LAB", key: "lab" },
+      { label: "Storage Location", key: "storageLocation" },
+      { label: "Storage Device", key: "storageDevice" },
+      { label: "# of Containers", key: "numberOfContainers" },
+      { label: "Amount per Container", key: "amountPerContainer" },
+      { label: "Unit of Measure", key: "unitOfMeasure" },
+      { label: "CAS #", key: "casNumber" },
+      { label: "Chemical Formula", key: "chemicalFormula" },
+      { label: "Molecular Weight", key: "molecularWeight" },
+      { label: "Vendor", key: "vendor" },
+      { label: "Catalog #", key: "catalogNumber" },
+      { label: "Found in Catalog", key: "foundInCatalog" },
+      { label: "PO#", key: "poNumber" },
+      { label: "Receipt Date", key: "receiptDate" },
+      { label: "Open Date", key: "openDate" },
+      { label: "MAX on Hand", key: "maxOnHand" },
+      { label: "Expiration Date", key: "expirationDate" },
+      { label: "Contact", key: "contact" },
+      { label: "Comments", key: "comments" },
+      { label: "Date Entered", key: "dateEntered" },
+      { label: "Permit #", key: "permitNumber" },
+      { label: "Barcode", key: "barcode" },
+      { label: "LAST_CHANGED", key: "lastChanged" },
+      { label: "Concentration", key: "concentration" },
+      { label: "Chemical Number", key: "chemicalNumber" },
+      { label: "Lot Number", key: "lotNumber" },
+      { label: "Multiple CAS (comma delimited)", key: "multipleCAS" },
+    ];
+
+    const prompt = `You are a data migration assistant. Your task is to map a user's uploaded spreadsheet columns to a canonical database schema.
+    
+Here are the user's headers and a few sample rows:
+Headers: ${JSON.stringify(headers)}
+Samples: ${JSON.stringify(sampleRows || [])}
+
+Here is our canonical schema:
+${JSON.stringify(canonicalColumns, null, 2)}
+
+For each user header, find the single best matching canonical 'key'. If there is no logical match, map it to "__skip__".
+Constraints:
+- You may only map a given canonical key ONCE across all headers. Do not assign two user headers to the same canonical key.
+- Try to be accurate based on semantic meaning, typical lab inventory vocabulary, and the sample values.
+
+Respond ONLY with a JSON object in this exact format, with no markdown code block fences and no other text:
+{
+  "mappings": [
+    {
+      "header": "the exact user header string",
+      "key": "the canonical key or __skip__",
+      "confidence": 0.95,
+      "reason": "short explanation of why this matches or why it was skipped"
+    }
+  ]
+}
+Ensure there is exactly one mapping per user header in the same order as the input headers.`;
+
+    const result = await model.generateContent({
+      contents: [{ role: 'user', parts: [{ text: prompt }] }],
+      generationConfig: {
+        responseMimeType: 'application/json',
+        responseSchema: {
+          type: SchemaType.OBJECT,
+          properties: {
+            mappings: {
+              type: SchemaType.ARRAY,
+              items: {
+                type: SchemaType.OBJECT,
+                properties: {
+                  header: { type: SchemaType.STRING },
+                  key: { type: SchemaType.STRING },
+                  confidence: { type: SchemaType.NUMBER },
+                  reason: { type: SchemaType.STRING },
+                },
+                required: ["header", "key", "confidence", "reason"]
+              }
+            }
+          },
+          required: ["mappings"]
+        }
+      }
+    });
+
+    let text = result.response.text();
+    text = text.replace(/^```(?:json)?\n?/i, '').replace(/```\n?$/, '').trim();
+    const parsed = JSON.parse(text);
+    res.json(parsed);
+  } catch (err) {
+    console.error('Column match error:', err);
+    res.status(500).json({ error: 'Failed to process column mapping.' });
+  }
+});
+
 export default router;