Add "Export to CSV" function

src/app/admin/applications/ApplicantDataTable.tsx

@@ -102,12 +102,61 @@ export default function ApplicantDataTable({
 		}
 	}
 
+	const exportCsv = (anchor: HTMLAnchorElement, apps: readonly Row[]) => {
+		const stringify = (v: boolean | number | string | undefined) =>
+			v ? v.toString() : ''
+		const quote = (s: string) => s.includes(',') ? `"${s}"` : s
+		const cell = (v: boolean | number | string | undefined) =>
+			quote(stringify(v))
+		const fields = (r: Row) => [
+			r.firstName,
+			r.lastName,
+			r.age,
+			r.email,
+			r.school,
+			r.phoneNumber,
+			r.countryOfResidence,
+			r.levelOfStudy,
+			r.agreedMlhCoC === 'Yes' ? 'TRUE' : 'FALSE',
+			r.agreedMlhMarketing === 'Yes' ? 'TRUE' : 'FALSE',
+			r.agreedMlhSharing === 'Yes' ? 'TRUE' : 'FALSE',
+		]
+		const row = (r: Row) => fields(r).map(cell).join(',')
+		const headers = () => [
+			'First Name',
+			'Last Name',
+			'Age',
+			'Email',
+			'School',
+			'Phone Number',
+			'Country',
+			'Current Level of Study',
+			'Code of Conduct Checkbox',
+			'MLH Marketing Opt In Checkbox',
+			'Privacy Policy Checkbox',
+		]
+		const csv = [headers(), ...apps.map(row)].join('\n')
+		anchor.setAttribute(
+			'href',
+			encodeURI(`data:text/csv;charset=utf-8,${csv}`),
+		)
+	}
+
+	const counts = countBy(applications, 'status')
+
 	return (
 		<div className="flex flex-col gap-2">
 			<p>
 				Tot/Acc/Rej/Wai/Und:{' '}
 				{applications.length}/{counts.accepted ?? 0}/{counts.rejected
 					?? 0}/{counts.waitlisted ?? 0}/{counts.undecided ?? 0}.{' '}
+				<a
+					className="text-hackuta-blue underline cursor-pointer"
+					onClick={(e) => exportCsv(e.currentTarget, applications)}
+					download="applications.csv"
+				>
+					Export to CSV
+				</a>
 			</p>
 			<DataTable
 				value={applications}