import { Card, Group, Loader, SimpleGrid, Stack, Text, ThemeIcon } from '@mantine/core';
import { DoorOpen } from 'lucide-react';
import {
  Bar,
  BarChart,
  CartesianGrid,
  ResponsiveContainer,
  Tooltip,
  XAxis,
  YAxis,
} from 'recharts';

import { useWarehouseGateStats } from '@/hooks/useWarehouses';

/**
 * Gate / dock throughput: items cleared through the gate today, the average
 * arrival→gate-clearance turnaround, and clearances per hour over the last 24h.
 */
export function GateThroughputCard() {
  const { data, isLoading } = useWarehouseGateStats();
  const byHour = data?.byHour ?? [];
  const hasActivity = byHour.some((h) => h.count > 0);

  return (
    <Card withBorder radius="lg" padding="lg" h="100%">
      <Group gap="sm" mb="md">
        <ThemeIcon size="lg" radius="md" color="indigo" variant="light">
          <DoorOpen size={20} />
        </ThemeIcon>
        <div>
          <Text fw={700}>Gate &amp; dock throughput</Text>
          <Text size="xs" c="dimmed">
            Gate clearances over the last 24 hours
          </Text>
        </div>
      </Group>

      {isLoading ? (
        <Group justify="center" h={220}>
          <Loader />
        </Group>
      ) : (
        <Stack gap="md">
          <SimpleGrid cols={2} spacing="sm">
            <Stack gap={2}>
              <Text size="xs" c="dimmed" tt="uppercase" fw={700}>
                Cleared today
              </Text>
              <Text fw={800} fz={30} lh={1.1}>
                {data?.clearedToday ?? 0}
              </Text>
              <Text size="xs" c="dimmed">
                through the gate
              </Text>
            </Stack>
            <Stack gap={2}>
              <Text size="xs" c="dimmed" tt="uppercase" fw={700}>
                Avg turnaround
              </Text>
              <Text fw={800} fz={30} lh={1.1}>
                {data?.avgTurnaroundHours == null ? '—' : `${data.avgTurnaroundHours} h`}
              </Text>
              <Text size="xs" c="dimmed">
                arrival → gate (30d)
              </Text>
            </Stack>
          </SimpleGrid>

          {hasActivity ? (
            <ResponsiveContainer width="100%" height={170}>
              <BarChart data={byHour} margin={{ top: 4, right: 8, left: -20, bottom: 0 }}>
                <CartesianGrid strokeDasharray="3 3" vertical={false} stroke="var(--mantine-color-gray-2)" />
                <XAxis dataKey="hour" interval={3} tick={{ fontSize: 11 }} />
                <YAxis allowDecimals={false} tick={{ fontSize: 12 }} />
                <Tooltip cursor={{ fill: 'var(--mantine-color-gray-1)' }} />
                <Bar dataKey="count" name="Cleared" fill="#4c6ef5" radius={[6, 6, 0, 0]} />
              </BarChart>
            </ResponsiveContainer>
          ) : (
            <Group justify="center" align="center" h={170}>
              <Text c="dimmed" size="sm">
                No gate clearances in the last 24 hours.
              </Text>
            </Group>
          )}
        </Stack>
      )}
    </Card>
  );
}