import { useMemo, useState } from 'react'
import { Link, useSearchParams } from 'react-router-dom'
import { Eye, Plus, Stethoscope, UserCheck, UserX, Building2 } from 'lucide-react'
import { PageShell } from '@/layouts/PageShell'
import { StatCard } from '@/components/dashboard/StatCard'
import { Card, CardContent } from '@/components/ui/card'
import { Table, TableBody, TableCell, TableHead, TableHeader, TableRow } from '@/components/ui/table'
import { Badge } from '@/components/ui/badge'
import { Button } from '@/components/ui/button'
import { StatusBadge } from '@/components/ui/status-badge'
import { PersonAvatar } from '@/components/ui/avatar'
import { TableToolbar, type TableFilter } from '@/components/table/TableToolbar'
import { RowActions } from '@/components/table/RowActions'
import { doctors as seed, organisations } from '@/mocks/data'
import type { Doctor } from '@/types'

const HOSPITAL_TYPES = new Set(['hospital', 'clinic'])

export function DoctorsPage() {
  const [params] = useSearchParams()
  const orgFilterParam = params.get('orgId') ?? 'all'
  const [rows] = useState<Doctor[]>([...seed])
  const [q, setQ] = useState('')
  const [status, setStatus] = useState('all')
  const [orgId, setOrgId] = useState(orgFilterParam)

  const hospitalOrgs = useMemo(
    () => organisations.filter((o) => HOSPITAL_TYPES.has(o.orgType) && o.status !== 'rejected'),
    [],
  )

  const kpis = useMemo(() => {
    const scoped = orgId === 'all' ? rows : rows.filter((d) => d.orgId === orgId)
    return {
      total: scoped.length,
      active: scoped.filter((d) => d.status === 'active').length,
      inactive: scoped.filter((d) => d.status === 'inactive').length,
      linked: scoped.filter((d) => d.hasLinkedAccount).length,
      hospitals: hospitalOrgs.length,
    }
  }, [rows, orgId, hospitalOrgs.length])

  const filtered = useMemo(() => {
    return rows.filter((d) => {
      if (orgId !== 'all' && d.orgId !== orgId) return false
      if (status !== 'all' && d.status !== status) return false
      if (q) {
        const needle = q.toLowerCase()
        if (
          !d.name.toLowerCase().includes(needle) &&
          !d.specialty.toLowerCase().includes(needle) &&
          !d.licenseNumber.toLowerCase().includes(needle) &&
          !d.orgName.toLowerCase().includes(needle) &&
          !d.email.toLowerCase().includes(needle)
        ) {
          return false
        }
      }
      return true
    })
  }, [rows, q, status, orgId])

  const filters: TableFilter[] = [
    {
      id: 'status',
      label: 'Status',
      value: status,
      onChange: setStatus,
      options: [
        { value: 'all', label: 'All statuses' },
        { value: 'active', label: 'Active' },
        { value: 'inactive', label: 'Inactive' },
      ],
    },
    {
      id: 'org',
      label: 'Hospital',
      value: orgId,
      onChange: setOrgId,
      options: [
        { value: 'all', label: 'All hospitals' },
        ...hospitalOrgs.map((o) => ({ value: o.id, label: o.name })),
      ],
    },
  ]

  const newHref = orgId !== 'all' ? `/doctors/new?orgId=${orgId}` : '/doctors/new'

  return (
    <PageShell title="Doctors" subtitle="Clinicians affiliated with hospital organisations — invite, review, attribute Rx & orders">
      <div className="grid gap-4 sm:grid-cols-2 xl:grid-cols-4">
        <StatCard label="Doctors" value={kpis.total} hint={`${kpis.active} active`} icon={Stethoscope} tone="brand" />
        <StatCard label="Active" value={kpis.active} hint="Can create Rx & orders" icon={UserCheck} tone="forest" />
        <StatCard label="Linked accounts" value={kpis.linked} hint="Login provisioned" icon={Building2} tone="muted" />
        <StatCard label="Inactive" value={kpis.inactive} hint="Suspended or left org" icon={UserX} tone="orange" />
      </div>

      <Card className="overflow-hidden">
        <TableToolbar
          search={q}
          onSearchChange={setQ}
          searchPlaceholder="Search name, specialty, license, hospital…"
          resultCount={filtered.length}
          filters={filters}
          onClearFilters={() => {
            setQ('')
            setStatus('all')
            setOrgId('all')
          }}
          actions={
            <Button asChild className="h-10 gap-2 shadow-none">
              <Link to={newHref}>
                <Plus className="h-4 w-4" />
                Add doctor
              </Link>
            </Button>
          }
        />
        <CardContent className="p-0">
          <Table>
            <TableHeader>
              <TableRow className="hover:bg-transparent">
                <TableHead>Doctor</TableHead>
                <TableHead>Specialty</TableHead>
                <TableHead>Hospital</TableHead>
                <TableHead>License</TableHead>
                <TableHead>Account</TableHead>
                <TableHead>Status</TableHead>
                <TableHead className="text-right">Actions</TableHead>
              </TableRow>
            </TableHeader>
            <TableBody>
              {filtered.length === 0 ? (
                <TableRow>
                  <TableCell colSpan={7} className="h-24 text-center text-muted-foreground">
                    No doctors match these filters
                  </TableCell>
                </TableRow>
              ) : null}
              {filtered.map((d) => (
                <TableRow key={d.id}>
                  <TableCell className="font-medium">
                    <Link to={`/doctors/${d.id}`} className="flex items-center gap-2.5 text-brand-700 hover:underline">
                      <PersonAvatar name={d.name} avatarUrl={d.avatarUrl} size="sm" />
                      {d.name}
                    </Link>
                  </TableCell>
                  <TableCell>{d.specialty}</TableCell>
                  <TableCell>
                    <Link to={`/organisations/${d.orgId}`} className="text-brand-700 hover:underline">
                      {d.orgName}
                    </Link>
                  </TableCell>
                  <TableCell className="font-mono text-xs">{d.licenseNumber}</TableCell>
                  <TableCell>
                    <Badge variant={d.hasLinkedAccount ? 'success' : 'outline'}>
                      {d.hasLinkedAccount ? 'Linked' : 'Invite pending'}
                    </Badge>
                  </TableCell>
                  <TableCell>
                    <StatusBadge domain="doctor" status={d.status} />
                  </TableCell>
                  <TableCell>
                    <RowActions
                      primary={[
                        { label: 'View', icon: <Eye className="h-3.5 w-3.5" />, to: `/doctors/${d.id}` },
                      ]}
                    />
                  </TableCell>
                </TableRow>
              ))}
            </TableBody>
          </Table>
        </CardContent>
      </Card>
    </PageShell>
  )
}