'use client'

import React from 'react'
import { Card, CardHeader, CardTitle, CardDescription } from '@/components/ui/card'
import { Label } from '@/components/ui/label'
import { Button } from '@/components/ui/button'
import { Input } from '@/components/ui/input'
import { Badge } from '@/components/ui/badge'
import {
  CreditCard,
  Calendar,
  Check,
  ChevronLeft,
  ChevronRight,
  RefreshCw,
  ShoppingBag,
  CheckCircle2,
} from 'lucide-react'
import { motion, AnimatePresence } from 'framer-motion'

interface StepBillingProps {
  selectedBillingInterval: 'one_time' | 'monthly'
  handleBillingIntervalChange: (val: 'one_time' | 'monthly') => void
  customerMode: 'select' | 'create'
  selectedEndCustomerId: string | null
  lastLicenseDate: string
  setLastLicenseDate: (date: string) => void
  prevStep: () => void
  nextStep: () => void
}

export function StepBilling({
  selectedBillingInterval,
  handleBillingIntervalChange,
  lastLicenseDate,
  setLastLicenseDate,
  prevStep,
  nextStep,
}: StepBillingProps) {
  const isOneTime = selectedBillingInterval === 'one_time'
  const isMonthly = selectedBillingInterval === 'monthly'

  return (
    <Card className="glass-dark border-white/10 h-[calc(100vh-8.5rem)] flex flex-col justify-between overflow-hidden relative">
      {/* ─── 1. FIXED HEADER (shrink-0) ─── */}
      <CardHeader className="py-2.5 px-4 shrink-0 border-b border-white/10 bg-slate-950/40 space-y-0">
        <div className="flex items-center justify-between gap-3">
          <div>
            <CardTitle className="text-lg font-bold flex items-center gap-2 text-white">
              <CreditCard className="w-4 h-4 text-primary" />
              Abrechnungsmodell wählen
            </CardTitle>
            <CardDescription className="text-[11px] text-slate-300 mt-0.5">
              Wählen Sie zwischen monatlicher Miete (Abonnement) oder einmaligem Softwarekauf.
            </CardDescription>
          </div>
          <Badge variant="outline" className="border-primary/30 text-primary bg-primary/10 text-xs px-2.5 py-0.5">
            Schritt 2 von 4
          </Badge>
        </div>
      </CardHeader>

      {/* ─── 2. NO-SCROLL MIDDLE CONTENT (flex-1 flex flex-col justify-center items-center overflow-hidden p-4) ─── */}
      <div className="flex-1 min-h-0 flex flex-col justify-center items-center overflow-hidden p-4 w-full">
        <div className="max-w-3xl w-full grid grid-cols-1 md:grid-cols-2 gap-4 items-start">
          {/* Option 1: Miete / Abo */}
          <div
            onClick={() => handleBillingIntervalChange('monthly')}
            className={`relative p-5 rounded-xl border-2 cursor-pointer transition-all duration-300 flex flex-col justify-between select-none ${
              isMonthly
                ? 'border-primary bg-primary/10 shadow-[0_0_20px_rgba(59,130,246,0.2)] ring-1 ring-primary/50'
                : 'border-white/5 bg-white/5 hover:border-white/20 hover:bg-white/[0.07]'
            }`}
          >
            <div>
              <div className="flex items-center justify-between gap-3 mb-3">
                <div className={`p-2.5 rounded-lg ${isMonthly ? 'bg-primary/20 text-primary border border-primary/30' : 'bg-white/5 text-slate-400 border border-white/10'}`}>
                  <RefreshCw className={`w-5 h-5 ${isMonthly ? 'animate-spin-slow' : ''}`} />
                </div>
                {isMonthly && (
                  <div className="w-5 h-5 rounded-full bg-primary flex items-center justify-center text-white shadow-md shadow-primary/30">
                    <Check className="w-3 h-3" />
                  </div>
                )}
              </div>

              <div className="space-y-0.5">
                <div className="flex items-center gap-2">
                  <h3 className="text-base font-bold text-white">Miete / Abo</h3>
                  <Badge variant="outline" className="text-[9px] px-1.5 py-0 bg-blue-500/10 border-blue-500/30 text-blue-400">
                    Empfohlen
                  </Badge>
                </div>
                <p className="text-[11px] font-medium text-slate-300">
                  Fortlaufende monatliche Abrechnung
                </p>
              </div>

              <p className="text-slate-400 text-[11px] mt-2 leading-relaxed">
                Maximale Flexibilität: Inklusive sämtlicher Software-Updates, Cloud-Dienste und Support. Jederzeit kündbar oder anpassbar.
              </p>
            </div>

            <div className="mt-3 pt-2.5 border-t border-white/10 flex items-center justify-between text-[11px]">
              <span className="text-slate-400">Zahlungsintervall:</span>
              <span className="text-primary font-semibold">monatlich</span>
            </div>
          </div>

          {/* Option 2: Kauf / Einmalkauf (mit integrierter Inline-Erweiterung) */}
          <div
            onClick={() => handleBillingIntervalChange('one_time')}
            className={`relative p-5 rounded-xl border-2 cursor-pointer transition-all duration-300 flex flex-col justify-between select-none ${
              isOneTime
                ? 'border-primary bg-primary/10 shadow-[0_0_20px_rgba(59,130,246,0.2)] ring-1 ring-primary/50'
                : 'border-white/5 bg-white/5 hover:border-white/20 hover:bg-white/[0.07]'
            }`}
          >
            <div>
              <div className="flex items-center justify-between gap-3 mb-3">
                <div className={`p-2.5 rounded-lg ${isOneTime ? 'bg-primary/20 text-primary border border-primary/30' : 'bg-white/5 text-slate-400 border border-white/10'}`}>
                  <ShoppingBag className="w-5 h-5" />
                </div>
                {isOneTime && (
                  <div className="w-5 h-5 rounded-full bg-primary flex items-center justify-center text-white shadow-md shadow-primary/30">
                    <Check className="w-3 h-3" />
                  </div>
                )}
              </div>

              <div className="space-y-0.5">
                <div className="flex items-center gap-2">
                  <h3 className="text-base font-bold text-white">Kauf / Einmalkauf</h3>
                  <Badge variant="outline" className="text-[9px] px-1.5 py-0 bg-slate-500/10 border-slate-500/30 text-slate-300">
                    Klassisch
                  </Badge>
                </div>
                <p className="text-[11px] font-medium text-slate-300">
                  Einmalige Lizenzgebühr
                </p>
              </div>

              <p className="text-slate-400 text-[11px] mt-2 leading-relaxed">
                Dauerhafte Lizenzrechte für die gekaufte Version inklusive 12 Monate kostenfreier Updates.
              </p>

              {/* Inline-Erweiterung für Kaufdatum / Stichtag */}
              <AnimatePresence>
                {isOneTime && (
                  <motion.div
                    initial={{ opacity: 0, height: 0, marginTop: 0 }}
                    animate={{ opacity: 1, height: 'auto', marginTop: 12 }}
                    exit={{ opacity: 0, height: 0, marginTop: 0 }}
                    transition={{ duration: 0.25, ease: 'easeInOut' }}
                    className="overflow-hidden"
                    onClick={(e) => e.stopPropagation()}
                  >
                    <div className="p-3 rounded-lg bg-slate-950/80 border border-white/10 space-y-2">
                      <div className="flex items-start gap-2">
                        <Calendar className="w-3.5 h-3.5 text-primary shrink-0 mt-0.5" />
                        <div className="space-y-0.5 flex-1">
                          <Label htmlFor="last-license-date" className="text-white text-[11px] font-bold block">
                            Datum letzter CASPOS-Kauf <span className="text-slate-400 font-normal">(optional)</span>
                          </Label>
                          <p className="text-[10px] text-slate-400 leading-tight">
                            Zur automatischen Berechnung der Update-Staffel (15% / 30% / 50%).
                          </p>
                        </div>
                      </div>

                      <div className="relative">
                        <Input
                          id="last-license-date"
                          type="date"
                          value={lastLicenseDate}
                          onChange={(e) => setLastLicenseDate(e.target.value)}
                          className="bg-slate-900 border-white/10 text-white text-xs h-8 focus:border-primary w-full"
                        />
                      </div>

                      {lastLicenseDate && (
                        <div className="text-[10px] text-emerald-400 flex items-center gap-1">
                          <CheckCircle2 className="w-3 h-3 text-emerald-400" /> Stichtag erfasst
                        </div>
                      )}
                    </div>
                  </motion.div>
                )}
              </AnimatePresence>
            </div>

            <div className="mt-3 pt-2.5 border-t border-white/10 flex items-center justify-between text-[11px]">
              <span className="text-slate-400">Zahlungsintervall:</span>
              <span className="text-slate-200 font-semibold">einmalig</span>
            </div>
          </div>
        </div>
      </div>

      {/* ─── 3. FIXED BOTTOM ACTION BAR (shrink-0) ─── */}
      <div className="shrink-0 border-t border-white/10 bg-slate-950/90 backdrop-blur-md px-4 py-2.5 flex flex-col sm:flex-row items-center justify-between gap-2 z-10">
        {/* Back Button */}
        <Button
          variant="outline"
          onClick={prevStep}
          className="w-full sm:w-auto border-white/10 text-white hover:bg-white/10 h-8 text-xs gap-1.5"
        >
          <ChevronLeft className="w-3.5 h-3.5" /> Zurück zu Schritt 1
        </Button>

        {/* Selected Model Status Chip */}
        <div className="flex items-center gap-2 px-2.5 py-1 rounded-lg bg-white/5 border border-white/10 text-white text-xs">
          <span className="text-slate-400">Gewähltes Modell:</span>
          <Badge
            variant="outline"
            className={`text-xs px-2 py-0 ${
              isMonthly
                ? 'border-blue-500/30 text-blue-400 bg-blue-500/10'
                : 'border-slate-500/30 text-slate-300 bg-slate-500/10'
            }`}
          >
            {isMonthly ? 'Monatliches Abo' : 'Einmaliger Kauf'}
          </Badge>
        </div>

        {/* Next Button */}
        <Button
          onClick={nextStep}
          className="w-full sm:w-auto bg-primary hover:bg-primary/90 text-white font-semibold px-5 shadow-md shadow-primary/20 h-8 text-xs gap-1.5"
        >
          Weiter zu Schritt 3 <ChevronRight className="w-3.5 h-3.5" />
        </Button>
      </div>
    </Card>
  )
}