'use client'

import { useState, useCallback, useEffect } from 'react'
import { Card, CardContent, CardHeader, CardTitle, CardDescription } from '@/components/ui/card'
import { Badge } from '@/components/ui/badge'
import { Button } from '@/components/ui/button'
import { Skeleton } from '@/components/ui/skeleton'
import {
  Table,
  TableBody,
  TableCell,
  TableHead,
  TableHeader,
  TableRow,
} from '@/components/ui/table'
import { useExtensionData } from '@/lib/extensions/use-extension-data'
import { useToast } from '@/components/ui/use-toast'
import {
  Building2,
  CheckCircle,
  XCircle,
  MapPin,
  Mail,
  Phone,
  Settings,
} from 'lucide-react'
import Link from 'next/link'
import type { WorkspaceComponentProps } from '@/lib/extensions/workspace-registry'
import type { TICCompanyProfile } from '@/extensions/general/tic/lib/tic-types'

function formatKSEK(value: number | null): string {
  if (value === null) return '—'
  return `${(value * 1000).toLocaleString('sv-SE')} kr`
}

function formatPercent(value: number | null): string {
  if (value === null) return '—'
  return `${value.toFixed(1)} %`
}

function toMs(epoch: number): number {
  // TIC returns epoch seconds; Date() expects milliseconds
  return epoch < 1e12 ? epoch * 1000 : epoch
}

function formatPeriod(start: number, end: number): string {
  const s = new Date(toMs(start))
  const e = new Date(toMs(end))
  const fmt = (d: Date) =>
    d.toLocaleDateString('sv-SE', { year: 'numeric', month: '2-digit', day: '2-digit' })
  return `${fmt(s)} – ${fmt(e)}`
}

function timeAgo(isoDate: string): string {
  const diff = Date.now() - new Date(isoDate).getTime()
  const minutes = Math.floor(diff / 60000)
  if (minutes < 1) return 'just nu'
  if (minutes < 60) return `${minutes} min sedan`
  const hours = Math.floor(minutes / 60)
  if (hours < 24) return `${hours} tim sedan`
  const days = Math.floor(hours / 24)
  return `${days} dag${days > 1 ? 'ar' : ''} sedan`
}

function ProfileSkeleton() {
  return (
    <div className="space-y-6">
      <div className="flex items-center gap-2">
        <Skeleton className="h-6 w-16" />
        <Skeleton className="h-6 w-16" />
        <Skeleton className="h-6 w-16" />
      </div>
      <div className="grid gap-6 md:grid-cols-2">
        <Card>
          <CardHeader>
            <Skeleton className="h-5 w-40" />
          </CardHeader>
          <CardContent className="space-y-3">
            <Skeleton className="h-4 w-full" />
            <Skeleton className="h-4 w-3/4" />
            <Skeleton className="h-4 w-1/2" />
          </CardContent>
        </Card>
        <Card>
          <CardHeader>
            <Skeleton className="h-5 w-40" />
          </CardHeader>
          <CardContent>
            <div className="grid grid-cols-2 gap-4">
              {Array.from({ length: 6 }).map((_, i) => (
                <Skeleton key={i} className="h-12 w-full" />
              ))}
            </div>
          </CardContent>
        </Card>
      </div>
    </div>
  )
}

export default function TicWorkspace({ userId }: WorkspaceComponentProps) {
  const { getByKey, save, isLoading: isDataLoading } = useExtensionData('general', 'tic')
  const { toast } = useToast()
  const [profile, setProfile] = useState<TICCompanyProfile | null>(null)
  const [isFetching, setIsFetching] = useState(false)
  const [noOrgNumber, setNoOrgNumber] = useState(false)
  const [initialLoad, setInitialLoad] = useState(true)

  // Load cached profile from extension data
  useEffect(() => {
    if (isDataLoading) return
    const cached = getByKey('company_profile')
    if (cached?.value) {
      setProfile(cached.value as unknown as TICCompanyProfile)
    }
    setInitialLoad(false)
  }, [isDataLoading, getByKey])

  const fetchProfile = useCallback(async () => {
    setIsFetching(true)
    setNoOrgNumber(false)

    try {
      // Get org_number from company settings
      const settingsRes = await fetch('/api/settings')
      if (!settingsRes.ok) {
        toast({ title: 'Kunde inte hämta inställningar', variant: 'destructive' })
        return
      }
      const { data: settings } = await settingsRes.json()
      const orgNumber = settings?.org_number

      if (!orgNumber) {
        setNoOrgNumber(true)
        return
      }

      const res = await fetch(
        `/api/extensions/ext/tic/profile?org_number=${encodeURIComponent(orgNumber)}`
      )

      if (!res.ok) {
        const { error } = await res.json()
        toast({ title: error ?? 'Kunde inte hämta företagsprofil', variant: 'destructive' })
        return
      }

      const { data } = await res.json()
      setProfile(data)
      await save('company_profile', data)
    } catch {
      toast({ title: 'Ett oväntat fel inträffade', variant: 'destructive' })
    } finally {
      setIsFetching(false)
    }
  }, [save, toast])

  // Auto-fetch on first visit when no cached data
  useEffect(() => {
    if (!initialLoad && !profile && !noOrgNumber && !isFetching) {
      fetchProfile()
    }
  }, [initialLoad, profile, noOrgNumber, isFetching, fetchProfile])

  if (initialLoad || isDataLoading) {
    return <ProfileSkeleton />
  }

  if (noOrgNumber) {
    return (
      <div className="flex flex-col items-center justify-center py-16 text-center">
        <Settings className="h-12 w-12 text-muted-foreground/40 mb-4" />
        <h3 className="text-lg font-medium text-foreground">
          Inget organisationsnummer
        </h3>
        <p className="text-sm text-muted-foreground mt-1 max-w-md">
          Ange organisationsnummer under Inställningar för att visa företagsprofilen.
        </p>
        <Button variant="outline" className="mt-4" asChild>
          <Link href="/settings">Gå till Inställningar</Link>
        </Button>
      </div>
    )
  }

  if (isFetching && !profile) {
    return <ProfileSkeleton />
  }

  if (!profile) return null

  const isActive = profile.activityStatus !== 'ceased'

  return (
    <div className="space-y-6">
      {/* Status bar */}
      <div className="flex flex-wrap items-center gap-2">
        <Badge variant={isActive ? 'success' : 'destructive'}>
          {isActive ? 'Aktiv' : 'Avregistrerat'}
        </Badge>
        {profile.registration.fTax && <Badge variant="outline">F-skatt</Badge>}
        {profile.registration.vat && <Badge variant="outline">Moms</Badge>}
        {profile.registration.payroll && <Badge variant="outline">Arbetsgivare</Badge>}

        <span className="ml-auto text-xs text-muted-foreground">
          Uppdaterad {timeAgo(profile.fetchedAt)}
        </span>
      </div>

      <div className="grid gap-6 md:grid-cols-2">
        {/* Company info card */}
        <Card>
          <CardHeader>
            <CardTitle className="flex items-center gap-2 text-base">
              <Building2 className="h-4 w-4" />
              {profile.companyName}
            </CardTitle>
            <CardDescription>
              {profile.orgNumber} &middot; {profile.legalEntityType}
            </CardDescription>
          </CardHeader>
          <CardContent className="space-y-3 text-sm">
            {profile.address && (
              <div className="flex items-start gap-2 text-muted-foreground">
                <MapPin className="h-3.5 w-3.5 mt-0.5 shrink-0" />
                <span>
                  {[profile.address.street, `${profile.address.postalCode} ${profile.address.city}`]
                    .filter(Boolean)
                    .join(', ')}
                </span>
              </div>
            )}
            {profile.email && (
              <div className="flex items-center gap-2 text-muted-foreground">
                <Mail className="h-3.5 w-3.5 shrink-0" />
                <span>{profile.email}</span>
              </div>
            )}
            {profile.phone && (
              <div className="flex items-center gap-2 text-muted-foreground">
                <Phone className="h-3.5 w-3.5 shrink-0" />
                <span>{profile.phone}</span>
              </div>
            )}
            {profile.sniCodes.length > 0 && (
              <div className="pt-2 border-t">
                <p className="text-xs font-medium text-muted-foreground mb-1">SNI-koder</p>
                <div className="space-y-0.5">
                  {profile.sniCodes
                    .filter((sni, i, arr) => arr.findIndex(s => s.code === sni.code) === i)
                    .map((sni) => (
                    <p key={sni.code} className="text-xs text-muted-foreground">
                      <span className="font-mono tabular-nums">{sni.code}</span>{' '}
                      {sni.name}
                    </p>
                  ))}
                </div>
              </div>
            )}
            {profile.bankAccounts.length > 0 && (
              <div className="pt-2 border-t">
                <p className="text-xs font-medium text-muted-foreground mb-1">Bankuppgifter</p>
                <div className="space-y-0.5">
                  {profile.bankAccounts.map((ba, i) => (
                    <p key={i} className="text-xs text-muted-foreground">
                      <span className="capitalize">{ba.type}</span>:{' '}
                      <span className="font-mono tabular-nums">{ba.accountNumber}</span>
                    </p>
                  ))}
                </div>
              </div>
            )}
            {profile.purpose && (
              <div className="pt-2 border-t">
                <p className="text-xs font-medium text-muted-foreground mb-1">Verksamhet</p>
                <p className="text-xs text-muted-foreground">{profile.purpose}</p>
              </div>
            )}
            {(profile.employeeRange || profile.turnoverRange) && (
              <div className="pt-2 border-t">
                {profile.employeeRange && (
                  <p className="text-xs text-muted-foreground">
                    Anställda: {profile.employeeRange}
                  </p>
                )}
                {profile.turnoverRange && (
                  <p className="text-xs text-muted-foreground">
                    Omsättning: {profile.turnoverRange}
                  </p>
                )}
              </div>
            )}
          </CardContent>
        </Card>

        {/* Financials card */}
        <Card>
          <CardHeader>
            <CardTitle className="text-base">Senaste bokslut</CardTitle>
            {profile.financials && (
              <CardDescription>
                {formatPeriod(profile.financials.periodStart, profile.financials.periodEnd)}
              </CardDescription>
            )}
          </CardHeader>
          <CardContent>
            {profile.financials ? (
              <div className="grid grid-cols-2 gap-4">
                <FinancialCell label="Omsättning" value={formatKSEK(profile.financials.netSalesK)} />
                <FinancialCell
                  label="Rörelseresultat"
                  value={formatKSEK(profile.financials.operatingProfitK)}
                  negative={(profile.financials.operatingProfitK ?? 0) < 0}
                />
                <FinancialCell label="Totala tillgångar" value={formatKSEK(profile.financials.totalAssetsK)} />
                <FinancialCell
                  label="Anställda"
                  value={profile.financials.numberOfEmployees !== null
                    ? String(profile.financials.numberOfEmployees)
                    : '—'}
                />
                <FinancialCell
                  label="Rörelsemarginal"
                  value={formatPercent(profile.financials.operatingMargin)}
                  negative={(profile.financials.operatingMargin ?? 0) < 0}
                />
                <FinancialCell
                  label="Soliditet"
                  value={formatPercent(profile.financials.equityAssetsRatio)}
                />
              </div>
            ) : (
              <p className="text-sm text-muted-foreground">Inga finansiella uppgifter tillgängliga.</p>
            )}
          </CardContent>
        </Card>
      </div>

      {/* Financial reports table */}
      {profile.financialReports.length > 0 && (
        <Card>
          <CardHeader>
            <CardTitle className="text-base">Årsredovisningar</CardTitle>
          </CardHeader>
          <CardContent>
            <Table>
              <TableHeader>
                <TableRow>
                  <TableHead>Period</TableHead>
                  <TableHead>Titel</TableHead>
                  <TableHead>Inlämnad</TableHead>
                  <TableHead>Reviderad</TableHead>
                  <TableHead>Revisionsutlåtande</TableHead>
                </TableRow>
              </TableHeader>
              <TableBody>
                {profile.financialReports
                  .filter((r) => !r.isInterimReport)
                  .sort((a, b) => {
                    const aEnd = a.periodEnd ? new Date(a.periodEnd).getTime() : 0
                    const bEnd = b.periodEnd ? new Date(b.periodEnd).getTime() : 0
                    return bEnd - aEnd
                  })
                  .slice(0, 10)
                  .map((report, i) => (
                    <TableRow key={report.financialReportSummaryId ?? i}>
                      <TableCell className="font-mono tabular-nums text-xs">
                        {report.periodStart && report.periodEnd
                          ? `${report.periodStart.slice(0, 10)} – ${report.periodEnd.slice(0, 10)}`
                          : '—'}
                      </TableCell>
                      <TableCell className="text-xs">{report.title ?? '—'}</TableCell>
                      <TableCell className="text-xs">
                        {report.arrivalDate
                          ? new Date(report.arrivalDate).toLocaleDateString('sv-SE')
                          : '—'}
                      </TableCell>
                      <TableCell>
                        {report.isAudited === true ? (
                          <CheckCircle className="h-3.5 w-3.5 text-success" />
                        ) : report.isAudited === false ? (
                          <XCircle className="h-3.5 w-3.5 text-muted-foreground" />
                        ) : (
                          <span className="text-xs text-muted-foreground">—</span>
                        )}
                      </TableCell>
                      <TableCell className="text-xs">{report.auditOpinion ?? '—'}</TableCell>
                    </TableRow>
                  ))}
              </TableBody>
            </Table>
          </CardContent>
        </Card>
      )}
    </div>
  )
}

function FinancialCell({
  label,
  value,
  negative = false,
}: {
  label: string
  value: string
  negative?: boolean
}) {
  return (
    <div>
      <p className="text-xs text-muted-foreground">{label}</p>
      <p
        className={`text-sm font-medium tabular-nums ${
          negative ? 'text-destructive' : 'text-foreground'
        }`}
      >
        {value}
      </p>
    </div>
  )
}