import { useState } from 'react'
import { useNavigate, useParams, useSearchParams } from 'react-router'
import {
  Alert,
  Box,
  Button,
  Chip,
  CircularProgress,
  Divider,
  Paper,
  TextField,
  Typography,
} from '@mui/material'
import {
  ArrowLeft,
  Building2,
  Calendar,
  CheckCircle2,
  Mail,
  MapPin,
  ShieldCheck,
  Layers,
} from 'lucide-react'
import { usePropertyById } from '../../hooks/useProperties'
import type { PropertyUnit } from '../../domain/property'

const FLOOR_LABEL = (level: number) =>
  level === 0 ? 'EG' : level < 0 ? `UG ${Math.abs(level)}` : `${level}.OG`

function UnitStatusChip({ unit }: { unit: PropertyUnit }) {
  if (unit.schattenmarktRelease?.enabled) {
    return (
      <Chip
        size="small"
        icon={<ShieldCheck size={11} />}
        label="PRE-MARKET"
        sx={{ bgcolor: '#f0fdf4', color: '#1a7a4a', border: '1px solid #86efac', fontWeight: 700, fontSize: '0.68rem', height: 20 }}
      />
    )
  }
  if (unit.available) {
    return <Chip size="small" label="Verfügbar" sx={{ bgcolor: '#eff6ff', color: '#1d4ed8', fontWeight: 600, fontSize: '0.68rem', height: 20 }} />
  }
  return <Chip size="small" label="Belegt" sx={{ bgcolor: '#f8fafc', color: '#64748b', fontWeight: 500, fontSize: '0.68rem', height: 20 }} />
}

function UnitRow({ unit, highlighted }: { unit: PropertyUnit; highlighted: boolean }) {
  const availableFrom = unit.schattenmarktRelease?.availableFrom ?? unit.leaseEndDate
  const monthlyRent = unit.rentPricePerSqm ? Math.round(unit.rentPricePerSqm / 12) : undefined

  return (
    <Box
      sx={{
        display: 'grid',
        gridTemplateColumns: '1fr 80px 110px 120px auto',
        gap: 1.5,
        alignItems: 'center',
        px: 2,
        py: 1.5,
        borderRadius: 1,
        bgcolor: highlighted ? '#faf5ff' : '#f8fafc',
        border: highlighted ? '1px solid #e9d5ff' : '1px solid #e2e8f0',
        mb: 1,
      }}
    >
      <Box>
        <Typography variant="body2" sx={{ fontWeight: 600 }}>
          {FLOOR_LABEL(unit.floorLevel)}{unit.unitLabel ? ` · ${unit.unitLabel}` : ''}
        </Typography>
        {unit.currentTenant && (
          <Typography variant="caption" color="text.secondary">{unit.currentTenant}</Typography>
        )}
      </Box>
      <Typography variant="body2" sx={{ fontWeight: 600 }}>{unit.areaSqm.toLocaleString('de-CH')} m²</Typography>
      <Typography variant="body2" color="text.secondary">
        {monthlyRent ? `CHF ${monthlyRent}/m²/Mt.` : '–'}
      </Typography>
      <Typography variant="body2" color="text.secondary">
        {availableFrom
          ? new Date(availableFrom).toLocaleDateString('de-CH', { month: 'long', year: 'numeric' })
          : '–'}
      </Typography>
      <UnitStatusChip unit={unit} />
    </Box>
  )
}

export default function PropertyDetail() {
  const { propertyId } = useParams<{ propertyId: string }>()
  const [searchParams] = useSearchParams()
  const highlightUnitId = searchParams.get('unit')
  const navigate = useNavigate()

  const { data: property, isLoading } = usePropertyById(propertyId ?? '')

  const [inquiryName, setInquiryName] = useState('')
  const [inquiryText, setInquiryText] = useState('')
  const [sent, setSent] = useState(false)

  if (isLoading) {
    return (
      <Box sx={{ display: 'flex', justifyContent: 'center', pt: 8 }}>
        <CircularProgress />
      </Box>
    )
  }

  if (!property) {
    return (
      <Box sx={{ p: 4 }}>
        <Typography color="text.secondary">Objekt nicht gefunden.</Typography>
      </Box>
    )
  }

  const preMarketUnits = (property.units ?? []).filter(u => u.schattenmarktRelease?.enabled)
  const otherUnits = (property.units ?? []).filter(u => !u.schattenmarktRelease?.enabled)
  const monthlyRentDisplay = Math.round(property.rentPricePerSqm / 12)

  function handleSendInquiry() {
    if (!inquiryName.trim() || !inquiryText.trim()) return
    setSent(true)
  }

  return (
    <Box sx={{ maxWidth: 860, mx: 'auto', p: { xs: 2, md: 3 } }}>
      {/* Back */}
      <Button
        startIcon={<ArrowLeft size={15} />}
        onClick={() => navigate(-1)}
        size="small"
        sx={{ mb: 2, textTransform: 'none', color: 'text.secondary' }}
      >
        Zurück zu den Ergebnissen
      </Button>

      {/* Header */}
      <Paper sx={{ mb: 2, overflow: 'hidden' }}>
        {property.images?.[0] && (
          <Box
            component="img"
            src={property.images[0]}
            alt={property.title}
            sx={{ width: '100%', height: 220, objectFit: 'cover' }}
          />
        )}
        <Box sx={{ p: 2.5 }}>
          <Box sx={{ display: 'flex', alignItems: 'flex-start', justifyContent: 'space-between', flexWrap: 'wrap', gap: 1 }}>
            <Box>
              <Box sx={{ display: 'flex', alignItems: 'center', gap: 0.75, mb: 0.5 }}>
                <Building2 size={15} color="#7c3aed" />
                <Typography variant="caption" sx={{ color: '#7c3aed', fontWeight: 700, textTransform: 'uppercase', letterSpacing: 0.5 }}>
                  {property.assetType}
                </Typography>
              </Box>
              <Typography variant="h5" sx={{ fontWeight: 700, mb: 0.5 }}>{property.title}</Typography>
              <Box sx={{ display: 'flex', alignItems: 'center', gap: 0.5 }}>
                <MapPin size={13} color="#64748b" />
                <Typography variant="body2" color="text.secondary">
                  {property.address.street} {property.address.houseNumber}, {property.address.postalCode} {property.address.city}
                </Typography>
              </Box>
            </Box>
            <Box sx={{ textAlign: 'right' }}>
              <Typography variant="h6" sx={{ fontWeight: 700, color: '#1e3a5f' }}>
                CHF {monthlyRentDisplay}/m²/Mt.
              </Typography>
              <Typography variant="caption" color="text.secondary">{property.areaSqm.toLocaleString('de-CH')} m² total</Typography>
            </Box>
          </Box>

          {preMarketUnits.length > 0 && (
            <Box sx={{ mt: 2, display: 'flex', alignItems: 'center', gap: 1, bgcolor: '#faf5ff', border: '1px solid #e9d5ff', borderRadius: 1, px: 1.5, py: 1 }}>
              <ShieldCheck size={14} color="#7c3aed" />
              <Typography sx={{ fontSize: '0.82rem', color: '#4c1d95', fontWeight: 600 }}>
                {preMarketUnits.length} Einheit{preMarketUnits.length !== 1 ? 'en' : ''} für Pre-Market freigegeben — noch vor offizieller Insertion
              </Typography>
            </Box>
          )}
        </Box>
      </Paper>

      {/* Units */}
      {(property.units ?? []).length > 0 && (
        <Paper sx={{ mb: 2, p: 2.5 }}>
          <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 2 }}>
            <Layers size={15} color="#374151" />
            <Typography variant="h6" sx={{ fontWeight: 700 }}>Einheiten</Typography>
          </Box>

          {/* Column headers */}
          <Box sx={{ display: 'grid', gridTemplateColumns: '1fr 80px 110px 120px auto', gap: 1.5, px: 2, mb: 0.75 }}>
            {['Einheit', 'Fläche', 'Miete', 'Verfügbar ab', 'Status'].map(h => (
              <Typography key={h} variant="caption" color="text.secondary" sx={{ fontWeight: 600 }}>{h}</Typography>
            ))}
          </Box>

          {preMarketUnits.map(u => (
            <UnitRow key={u.id} unit={u} highlighted={u.id === highlightUnitId || preMarketUnits.length === 1} />
          ))}
          {otherUnits.map(u => (
            <UnitRow key={u.id} unit={u} highlighted={u.id === highlightUnitId} />
          ))}
        </Paper>
      )}

      {/* Inquiry */}
      <Paper sx={{ p: 2.5 }}>
        <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 2 }}>
          <Mail size={15} color="#374151" />
          <Typography variant="h6" sx={{ fontWeight: 700 }}>Verwaltung kontaktieren</Typography>
        </Box>

        {sent ? (
          <Alert
            icon={<CheckCircle2 size={18} />}
            severity="success"
            sx={{ borderRadius: 1 }}
          >
            Ihre Anfrage wurde übermittelt. Die Verwaltung meldet sich in Kürze.
          </Alert>
        ) : (
          <Box sx={{ display: 'flex', flexDirection: 'column', gap: 1.5 }}>
            <Box sx={{ display: 'flex', gap: 1.5 }}>
              <Box sx={{ flex: 1 }}>
                <Typography variant="caption" color="text.secondary" sx={{ display: 'block', mb: 0.5 }}>Ihr Name</Typography>
                <TextField
                  size="small"
                  fullWidth
                  placeholder="Max Muster"
                  value={inquiryName}
                  onChange={e => setInquiryName(e.target.value)}
                />
              </Box>
              <Box sx={{ flex: 1 }}>
                <Typography variant="caption" color="text.secondary" sx={{ display: 'block', mb: 0.5 }}>Bezug</Typography>
                <TextField
                  size="small"
                  fullWidth
                  value={
                    highlightUnitId
                      ? (property.units?.find(u => u.id === highlightUnitId)?.unitLabel ?? 'Einheit')
                      : property.title
                  }
                  InputProps={{ readOnly: true }}
                  sx={{ '& .MuiInputBase-input': { color: 'text.secondary', fontSize: '0.85rem' } }}
                />
              </Box>
            </Box>
            <Box>
              <Typography variant="caption" color="text.secondary" sx={{ display: 'block', mb: 0.5 }}>Ihre Nachricht</Typography>
              <TextField
                size="small"
                fullWidth
                multiline
                rows={4}
                placeholder="Wir interessieren uns für die Fläche und möchten gerne einen Besichtigungstermin vereinbaren..."
                value={inquiryText}
                onChange={e => setInquiryText(e.target.value)}
              />
            </Box>
            <Box sx={{ display: 'flex', alignItems: 'center', justifyContent: 'space-between' }}>
              <Box sx={{ display: 'flex', alignItems: 'center', gap: 0.5 }}>
                <Calendar size={12} color="#64748b" />
                <Typography variant="caption" color="text.secondary">Antwortzeit: typisch 1–2 Werktage</Typography>
              </Box>
              <Button
                variant="contained"
                size="small"
                disabled={!inquiryName.trim() || !inquiryText.trim()}
                onClick={handleSendInquiry}
                startIcon={<Mail size={14} />}
                sx={{ bgcolor: '#7c3aed', '&:hover': { bgcolor: '#6d28d9' }, textTransform: 'none' }}
              >
                Anfrage senden
              </Button>
            </Box>
          </Box>
        )}
      </Paper>

      <Divider sx={{ my: 2 }} />
      <Typography variant="caption" color="text.secondary" sx={{ display: 'block', lineHeight: 1.5 }}>
        Diese Fläche ist noch nicht offiziell auf dem Markt. Die Verwaltung hat sie explizit für qualifizierte Suchanfragen freigegeben. Ihre Anfrage wird vertraulich behandelt.
      </Typography>
    </Box>
  )
}