import { useState } from 'react'
import {
  Drawer,
  Box,
  Typography,
  IconButton,
  Chip,
  Divider,
  TextField,
  Button,
  Switch,
  FormControlLabel,
  Tooltip,
} from '@mui/material'
import { X, MapPin, Calendar, DollarSign, Eye, Activity } from 'lucide-react'
import { useReminderStore } from '../../stores/reminderStore'
import { useReminder, useCompleteReminder, useDismissReminder, useSnoozeReminder } from '../../hooks/useReminders'
import { ReminderPriorityBadge } from './ReminderPriorityBadge'
import { ReminderTypeBadge } from './ReminderTypeBadge'
import { ReminderDaysIndicator } from './ReminderDaysIndicator'
import { ReminderStatus, ShadowMarketRisk } from '../../domain/reminder'
import type { ReminderActivity } from '../../domain/reminder'

const SHADOW_RISK_COLOR: Record<string, string> = {
  NONE: '#64748b',
  LOW: '#16a34a',
  MEDIUM: '#ca8a04',
  HIGH: '#dc2626',
}

const SHADOW_RISK_LABEL: Record<string, string> = {
  NONE: 'Kein Risiko',
  LOW: 'Niedrig',
  MEDIUM: 'Mittel',
  HIGH: 'Hoch',
}

const STATUS_CHIP_COLOR: Record<string, 'default' | 'success' | 'warning' | 'error' | 'info'> = {
  ACTIVE: 'info',
  SNOOZED: 'warning',
  COMPLETED: 'success',
  DISMISSED: 'default',
}

const STATUS_LABEL: Record<string, string> = {
  ACTIVE: 'Aktiv',
  SNOOZED: 'Schlummernd',
  COMPLETED: 'Erledigt',
  DISMISSED: 'Verworfen',
}

const ACTION_LABEL: Record<string, string> = {
  CREATED: 'Erstellt',
  SNOOZED: 'Zurückgestellt',
  COMPLETED: 'Erledigt',
  DISMISSED: 'Verworfen',
  NOTED: 'Notiz',
}

function SectionTitle({ icon, children }: { icon: React.ReactNode; children: React.ReactNode }) {
  return (
    <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 1.5 }}>
      {icon}
      <Typography variant="subtitle2" sx={{ fontWeight: 700, color: '#1e293b', fontSize: '0.8125rem' }}>
        {children}
      </Typography>
    </Box>
  )
}

function DateRow({ label, value }: { label: string; value?: string }) {
  if (!value) return null
  return (
    <Box sx={{ display: 'grid', gridTemplateColumns: '120px 1fr', gap: 1, alignItems: 'baseline' }}>
      <Typography variant="caption" color="text.secondary">{label}</Typography>
      <Typography variant="body2" sx={{ fontWeight: 500 }}>{new Date(value).toLocaleDateString('de-CH')}</Typography>
    </Box>
  )
}

function ActivityEntry({ entry }: { entry: ReminderActivity }) {
  return (
    <Box sx={{ display: 'flex', gap: 1.5 }}>
      <Box sx={{ display: 'flex', flexDirection: 'column', alignItems: 'center', flexShrink: 0 }}>
        <Box sx={{ width: 8, height: 8, borderRadius: '50%', bgcolor: '#94a3b8', mt: '4px' }} />
        <Box sx={{ width: 1, flex: 1, bgcolor: '#e2e8f0', mt: 0.5 }} />
      </Box>
      <Box sx={{ pb: 1.5, minWidth: 0 }}>
        <Box sx={{ display: 'flex', gap: 1, alignItems: 'baseline', flexWrap: 'wrap' }}>
          <Typography variant="caption" sx={{ fontWeight: 600, color: '#1e293b' }}>
            {ACTION_LABEL[entry.action]}
          </Typography>
          <Typography variant="caption" color="text.secondary">
            {entry.by} · {new Date(entry.at).toLocaleDateString('de-CH')}
          </Typography>
        </Box>
        {entry.note && (
          <Typography variant="caption" color="text.secondary" sx={{ display: 'block', mt: 0.25 }}>
            {entry.note}
          </Typography>
        )}
      </Box>
    </Box>
  )
}

export function ReminderDetailDrawer() {
  const { selectedId, drawerOpen, setDrawerOpen, setSelectedId } = useReminderStore()
  const { data: reminder } = useReminder(selectedId ?? '')
  const complete = useCompleteReminder()
  const dismiss = useDismissReminder()
  const snooze = useSnoozeReminder()

  const [noteValue, setNoteValue] = useState('')
  const [snoozeDate, setSnoozeDate] = useState('')

  function handleClose() {
    setDrawerOpen(false)
    setSelectedId(null)
  }

  const isNew = !selectedId

  return (
    <Drawer
      anchor="right"
      open={drawerOpen}
      onClose={handleClose}
      slotProps={{ paper: { sx: { width: 480, display: 'flex', flexDirection: 'column' } } }}
    >
      {/* Header */}
      <Box
        sx={{
          px: 2.5,
          py: 2,
          borderBottom: '1px solid #e2e8f0',
          display: 'flex',
          alignItems: 'flex-start',
          gap: 1,
          flexShrink: 0,
        }}
      >
        <Box sx={{ flex: 1, display: 'flex', flexDirection: 'column', gap: 1, minWidth: 0 }}>
          {isNew ? (
            <Typography variant="subtitle1" sx={{ fontWeight: 700 }}>Neuer Reminder</Typography>
          ) : reminder ? (
            <>
              <Box sx={{ display: 'flex', gap: 1, flexWrap: 'wrap', alignItems: 'center' }}>
                <ReminderTypeBadge type={reminder.type} />
                <ReminderPriorityBadge priority={reminder.priority} />
                <Chip
                  label={STATUS_LABEL[reminder.status]}
                  color={STATUS_CHIP_COLOR[reminder.status]}
                  size="small"
                  sx={{ height: 20, fontSize: '0.7rem' }}
                />
              </Box>
              <ReminderDaysIndicator dueDate={reminder.dueDate} />
            </>
          ) : null}
        </Box>
        <IconButton size="small" onClick={handleClose} sx={{ flexShrink: 0 }}>
          <X size={18} />
        </IconButton>
      </Box>

      {/* Scrollable body */}
      <Box sx={{ flex: 1, overflowY: 'auto', p: 2.5 }} className="flex flex-col gap-5">
        {isNew && (
          <Typography variant="body2" color="text.secondary">
            Neue Reminder-Erstellung noch nicht implementiert.
          </Typography>
        )}

        {reminder && (
          <>
            {/* 2. Property */}
            <Box>
              <SectionTitle icon={<MapPin size={15} color="#64748b" />}>Objekt</SectionTitle>
              <Box className="flex flex-col gap-1">
                <Typography variant="body2" sx={{ fontWeight: 600 }}>{reminder.propertyTitle}</Typography>
                <Typography variant="caption" color="text.secondary">
                  {reminder.propertyCity}{reminder.propertyDistrict ? ` · ${reminder.propertyDistrict}` : ''}
                </Typography>
                <Typography variant="caption" color="text.secondary">Mieter: {reminder.tenantName}</Typography>
                <Typography variant="caption" color="text.secondary">Fläche: {reminder.areaSqm.toLocaleString('de-CH')} m²</Typography>
              </Box>
            </Box>

            <Divider />

            {/* 3. Dates */}
            <Box>
              <SectionTitle icon={<Calendar size={15} color="#64748b" />}>Daten &amp; Fristen</SectionTitle>
              <Box className="flex flex-col gap-1.5">
                <DateRow label="Fälligkeitsdatum" value={reminder.dueDate} />
                <DateRow label="Ereignisdatum" value={reminder.eventDate} />
                <DateRow label="Vertragsende" value={reminder.contractEndDate} />
                <DateRow label="Break-Option" value={reminder.breakOptionDate} />
                {reminder.snoozedUntil && (
                  <DateRow label="Schlummern bis" value={reminder.snoozedUntil} />
                )}
              </Box>
            </Box>

            <Divider />

            {/* 4. Financials */}
            <Box>
              <SectionTitle icon={<DollarSign size={15} color="#64748b" />}>Finanzen</SectionTitle>
              <Box className="flex flex-col gap-1.5">
                <Box sx={{ display: 'grid', gridTemplateColumns: '120px 1fr', gap: 1 }}>
                  <Typography variant="caption" color="text.secondary">Miete/m²</Typography>
                  <Typography variant="body2" sx={{ fontWeight: 500 }}>
                    {reminder.currency} {reminder.currentRentPerSqm.toLocaleString('de-CH')} / Monat
                  </Typography>
                </Box>
                <Box sx={{ display: 'grid', gridTemplateColumns: '120px 1fr', gap: 1 }}>
                  <Typography variant="caption" color="text.secondary">Total / Monat</Typography>
                  <Typography variant="body2" sx={{ fontWeight: 500 }}>
                    {reminder.currency} {(reminder.currentRentPerSqm * reminder.areaSqm).toLocaleString('de-CH')}
                  </Typography>
                </Box>
              </Box>
            </Box>

            <Divider />

            {/* 5. Pre-Market */}
            <Box>
              <SectionTitle icon={<Eye size={15} color="#64748b" />}>Pre-Market Risiko</SectionTitle>
              <Box className="flex flex-col gap-2">
                <Box sx={{ display: 'flex', alignItems: 'center', gap: 1 }}>
                  <Box
                    sx={{
                      width: 10,
                      height: 10,
                      borderRadius: '50%',
                      bgcolor: SHADOW_RISK_COLOR[reminder.shadowMarketRisk],
                    }}
                  />
                  <Typography variant="body2" sx={{ fontWeight: 600, color: SHADOW_RISK_COLOR[reminder.shadowMarketRisk] }}>
                    {SHADOW_RISK_LABEL[reminder.shadowMarketRisk]}
                  </Typography>
                </Box>
                <Tooltip title="Nur Anzeige — Änderung über Objektverwaltung">
                  <FormControlLabel
                    control={<Switch checked={reminder.schattenmarktEnabled} size="small" readOnly />}
                    label={
                      <Typography variant="caption">
                        Pre-Market aktiviert
                      </Typography>
                    }
                  />
                </Tooltip>
              </Box>
            </Box>

            <Divider />

            {/* 6. Note */}
            <Box>
              <Typography variant="subtitle2" sx={{ fontWeight: 700, mb: 1, fontSize: '0.8125rem' }}>Notiz</Typography>
              <TextField
                multiline
                rows={3}
                fullWidth
                size="small"
                value={noteValue || (reminder.note ?? '')}
                onChange={e => setNoteValue(e.target.value)}
                placeholder="Notiz hinzufügen…"
                sx={{ '& .MuiInputBase-root': { fontSize: '0.8125rem' } }}
              />
            </Box>

            {/* Actions */}
            {(reminder.status === ReminderStatus.ACTIVE || reminder.status === ReminderStatus.SNOOZED) && (
              <>
                <Divider />
                <Box className="flex flex-col gap-2">
                  <Typography variant="subtitle2" sx={{ fontWeight: 700, fontSize: '0.8125rem' }}>Aktionen</Typography>
                  <Box className="flex gap-2">
                    <Button
                      size="small"
                      variant="contained"
                      color="success"
                      sx={{ textTransform: 'none', flex: 1 }}
                      onClick={() => complete.mutate({ id: reminder.id, note: noteValue || undefined })}
                    >
                      Erledigt
                    </Button>
                    <Button
                      size="small"
                      variant="outlined"
                      color="error"
                      sx={{ textTransform: 'none', flex: 1 }}
                      onClick={() => dismiss.mutate({ id: reminder.id, note: noteValue || undefined })}
                    >
                      Verwerfen
                    </Button>
                  </Box>
                  <Box className="flex gap-2 items-center">
                    <TextField
                      type="date"
                      size="small"
                      value={snoozeDate}
                      onChange={e => setSnoozeDate(e.target.value)}
                      sx={{ flex: 1, '& .MuiInputBase-root': { fontSize: '0.8125rem' } }}
                    />
                    <Button
                      size="small"
                      variant="outlined"
                      disabled={!snoozeDate}
                      sx={{ textTransform: 'none', whiteSpace: 'nowrap' }}
                      onClick={() => snoozeDate && snooze.mutate({ id: reminder.id, until: snoozeDate })}
                    >
                      Schlummern bis
                    </Button>
                  </Box>
                </Box>
              </>
            )}

            <Divider />

            {/* 7. Activity */}
            <Box>
              <SectionTitle icon={<Activity size={15} color="#64748b" />}>Aktivitätslog</SectionTitle>
              <Box>
                {[...reminder.activity].reverse().map((entry, i) => (
                  <ActivityEntry key={i} entry={entry} />
                ))}
              </Box>
            </Box>
          </>
        )}
      </Box>
    </Drawer>
  )
}