'use client'

import { useState, useEffect } from 'react'
import { useI18n } from '@/lib/i18n'
import { ALLOWED_PAYMENT_CURRENCIES } from '@/lib/payment-currencies'

interface RedeemPointsModalProps {
  isOpen: boolean
  onClose: () => void
  currentPoints: number
  onRedeemSuccess: () => void
}

export default function RedeemPointsModal({
  isOpen,
  onClose,
  currentPoints,
  onRedeemSuccess,
}: RedeemPointsModalProps) {
  const { t } = useI18n()
  const [pointsToRedeem, setPointsToRedeem] = useState<string>('')
  const [cryptoCurrency, setCryptoCurrency] = useState<string>('btc')
  const [walletAddress, setWalletAddress] = useState<string>('')
  const [loading, setLoading] = useState(false)
  const [error, setError] = useState<string>('')
  const [success, setSuccess] = useState(false)
  const [redemptionDetails, setRedemptionDetails] = useState<any>(null)
  const [pointsToCryptoChf, setPointsToCryptoChf] = useState<number>(100)
  const [minRedemptionPoints, setMinRedemptionPoints] = useState<number>(1000)
  const [estimatedCrypto, setEstimatedCrypto] = useState<number>(0)

  useEffect(() => {
    if (isOpen) {
      fetchRedemptionSettings()
      // Reset form
      setPointsToRedeem('')
      setWalletAddress('')
      setCryptoCurrency('btc')
      setError('')
      setSuccess(false)
      setRedemptionDetails(null)
    }
  }, [isOpen])

  const fetchRedemptionSettings = async () => {
    try {
      const response = await fetch('/api/referral-points', {
        credentials: 'include',
      })
      if (response.ok) {
        const data = await response.json()
        setPointsToCryptoChf(data.points_to_crypto_chf || data.points_to_chf || 100)
        setMinRedemptionPoints(data.min_redemption_points || 1000)
      }
    } catch (error) {
      console.error('Error fetching redemption settings:', error)
    }
  }

  useEffect(() => {
    // Calculate estimated crypto amount when points or currency changes
    if (pointsToRedeem && !isNaN(parseFloat(pointsToRedeem))) {
      const points = parseFloat(pointsToRedeem)
      const chfValue = points / pointsToCryptoChf
      // Mock exchange rates (should match API)
      const mockRates: Record<string, number> = {
        'btc': 85000,
        'eth': 2500,
        'sol': 100,
        'xrp': 0.6,
        'bnbbsc': 300,
        'usdterc20': 0.9,
      }
      const rate = mockRates[cryptoCurrency.toLowerCase()] || 1
      setEstimatedCrypto(chfValue / rate)
    } else {
      setEstimatedCrypto(0)
    }
  }, [pointsToRedeem, cryptoCurrency, pointsToCryptoChf])

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault()
    setError('')
    setLoading(true)

    try {
      const points = parseFloat(pointsToRedeem)
      
      if (isNaN(points) || points <= 0) {
        setError(t('redeemPoints.invalidPoints'))
        setLoading(false)
        return
      }

      if (points < minRedemptionPoints) {
        setError(t('redeemPoints.minPoints', { min: minRedemptionPoints }))
        setLoading(false)
        return
      }

      if (points > currentPoints) {
        setError(t('redeemPoints.insufficientPoints'))
        setLoading(false)
        return
      }

      if (!walletAddress.trim()) {
        setError(t('redeemPoints.invalidWallet'))
        setLoading(false)
        return
      }

      const response = await fetch('/api/referral-points/redeem', {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        credentials: 'include',
        body: JSON.stringify({
          points: points,
          crypto_currency: cryptoCurrency,
          wallet_address: walletAddress.trim(),
        }),
      })

      const data = await response.json()

      if (!response.ok) {
        setError(data.error || t('redeemPoints.error'))
        setLoading(false)
        return
      }

      setSuccess(true)
      setRedemptionDetails(data)
      onRedeemSuccess()
    } catch (error: any) {
      console.error('Error redeeming points:', error)
      setError(error.message || t('redeemPoints.error'))
    } finally {
      setLoading(false)
    }
  }

  if (!isOpen) return null

  const pointsNum = parseFloat(pointsToRedeem) || 0
  const chfValue = pointsNum / pointsToCryptoChf

  return (
    <div
      style={{
        position: 'fixed',
        top: 0,
        left: 0,
        right: 0,
        bottom: 0,
        backgroundColor: 'rgba(0, 0, 0, 0.5)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center',
        zIndex: 1000,
        padding: '20px',
      }}
      onClick={onClose}
    >
      <div
        style={{
          background: 'var(--bg)',
          borderRadius: '12px',
          padding: '32px',
          maxWidth: '500px',
          width: '100%',
          maxHeight: '90vh',
          overflowY: 'auto',
          boxShadow: '0 4px 20px rgba(0, 0, 0, 0.3)',
        }}
        onClick={(e) => e.stopPropagation()}
      >
        <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', marginBottom: '24px' }}>
          <h2 style={{ margin: 0, fontSize: '24px', fontWeight: 600 }}>
            {t('redeemPoints.title')}
          </h2>
          <button
            onClick={onClose}
            style={{
              background: 'transparent',
              border: 'none',
              fontSize: '24px',
              cursor: 'pointer',
              color: 'var(--muted)',
              padding: 0,
              width: '32px',
              height: '32px',
              display: 'flex',
              alignItems: 'center',
              justifyContent: 'center',
            }}
          >
            ×
          </button>
        </div>

        {success ? (
          <div>
            <div style={{ 
              background: '#0a7931', 
              color: 'white', 
              padding: '16px', 
              borderRadius: '8px', 
              marginBottom: '24px' 
            }}>
              <strong>✓ {t('redeemPoints.success')}</strong>
            </div>
            {redemptionDetails && (
              <div style={{ marginBottom: '24px' }}>
                <p><strong>{t('redeemPoints.redemptionId')}:</strong> #{redemptionDetails.redemption_id}</p>
                <p><strong>{t('redeemPoints.pointsRedeemed')}:</strong> {redemptionDetails.points_redeemed.toFixed(2)}</p>
                <p><strong>{t('redeemPoints.cryptoAmount')}:</strong> {redemptionDetails.crypto_amount.toFixed(8)} {redemptionDetails.crypto_currency.toUpperCase()}</p>
                <p><strong>{t('redeemPoints.newBalance')}:</strong> {redemptionDetails.new_balance.toFixed(2)} {t('redeemPoints.points')}</p>
                <p style={{ marginTop: '16px', fontSize: '14px', color: 'var(--muted)' }}>
                  {redemptionDetails.message}
                </p>
              </div>
            )}
            <button
              onClick={onClose}
              style={{
                width: '100%',
                padding: '12px',
                background: 'var(--primary)',
                color: 'white',
                border: 'none',
                borderRadius: '8px',
                fontSize: '16px',
                cursor: 'pointer',
                fontWeight: 500,
              }}
            >
              {t('common.close')}
            </button>
          </div>
        ) : (
          <form onSubmit={handleSubmit}>
            <div style={{ marginBottom: '20px' }}>
              <div style={{ 
                background: 'var(--bg-soft)', 
                padding: '16px', 
                borderRadius: '8px', 
                marginBottom: '16px' 
              }}>
                <div style={{ fontSize: '14px', color: 'var(--muted)', marginBottom: '4px' }}>
                  {t('redeemPoints.currentBalance')}
                </div>
                <div style={{ fontSize: '24px', fontWeight: 600, color: '#0a7931' }}>
                  ⭐ {currentPoints.toFixed(2)} {t('redeemPoints.points')}
                </div>
              </div>

              <label style={{ display: 'block', marginBottom: '8px', fontSize: '14px', fontWeight: 500 }}>
                {t('redeemPoints.selectCrypto')} *
              </label>
              <select
                value={cryptoCurrency}
                onChange={(e) => setCryptoCurrency(e.target.value)}
                style={{
                  width: '100%',
                  padding: '12px',
                  background: 'var(--bg-soft)',
                  border: '1px solid var(--border)',
                  borderRadius: '8px',
                  fontSize: '14px',
                  color: 'var(--text)',
                  marginBottom: '16px',
                }}
                required
              >
                {ALLOWED_PAYMENT_CURRENCIES.map((currency) => (
                  <option key={currency} value={currency}>
                    {currency.toUpperCase()}
                  </option>
                ))}
              </select>

              <label style={{ display: 'block', marginBottom: '8px', fontSize: '14px', fontWeight: 500 }}>
                {t('redeemPoints.walletAddress')} *
              </label>
              <input
                type="text"
                value={walletAddress}
                onChange={(e) => setWalletAddress(e.target.value)}
                placeholder={t('redeemPoints.walletAddressPlaceholder')}
                style={{
                  width: '100%',
                  padding: '12px',
                  background: 'var(--bg-soft)',
                  border: '1px solid var(--border)',
                  borderRadius: '8px',
                  fontSize: '14px',
                  color: 'var(--text)',
                  marginBottom: '16px',
                  fontFamily: 'monospace',
                }}
                required
              />

              <label style={{ display: 'block', marginBottom: '8px', fontSize: '14px', fontWeight: 500 }}>
                {t('redeemPoints.pointsToRedeem')} *
                <span style={{ marginLeft: '8px', fontSize: '12px', color: 'var(--muted)', fontWeight: 'normal' }}>
                  ({t('redeemPoints.min')}: {minRedemptionPoints})
                </span>
              </label>
              <input
                type="number"
                value={pointsToRedeem}
                onChange={(e) => setPointsToRedeem(e.target.value)}
                min={minRedemptionPoints}
                max={currentPoints}
                step="1"
                placeholder={minRedemptionPoints.toString()}
                style={{
                  width: '100%',
                  padding: '12px',
                  background: 'var(--bg-soft)',
                  border: '1px solid var(--border)',
                  borderRadius: '8px',
                  fontSize: '14px',
                  color: 'var(--text)',
                  marginBottom: '16px',
                }}
                required
              />

              {pointsNum > 0 && (
                <div style={{ 
                  background: 'var(--bg-soft)', 
                  padding: '12px', 
                  borderRadius: '8px', 
                  marginBottom: '16px',
                  fontSize: '14px',
                }}>
                  <div style={{ marginBottom: '4px' }}>
                    <strong>{t('redeemPoints.estimatedValue')}:</strong>
                  </div>
                  <div style={{ color: 'var(--muted)' }}>
                    {chfValue.toFixed(2)} CHF ≈ {estimatedCrypto.toFixed(8)} {cryptoCurrency.toUpperCase()}
                  </div>
                </div>
              )}

              {error && (
                <div style={{
                  background: '#ff4444',
                  color: 'white',
                  padding: '12px',
                  borderRadius: '8px',
                  marginBottom: '16px',
                  fontSize: '14px',
                }}>
                  {error}
                </div>
              )}
            </div>

            <div style={{ display: 'flex', gap: '12px' }}>
              <button
                type="button"
                onClick={onClose}
                style={{
                  flex: 1,
                  padding: '12px',
                  background: 'transparent',
                  color: 'var(--text)',
                  border: '1px solid var(--border)',
                  borderRadius: '8px',
                  fontSize: '16px',
                  cursor: 'pointer',
                  fontWeight: 500,
                }}
              >
                {t('common.cancel')}
              </button>
              <button
                type="submit"
                disabled={loading || pointsNum < minRedemptionPoints || pointsNum > currentPoints}
                style={{
                  flex: 1,
                  padding: '12px',
                  background: loading || pointsNum < minRedemptionPoints || pointsNum > currentPoints 
                    ? 'var(--muted)' 
                    : 'var(--primary)',
                  color: 'white',
                  border: 'none',
                  borderRadius: '8px',
                  fontSize: '16px',
                  cursor: loading || pointsNum < minRedemptionPoints || pointsNum > currentPoints 
                    ? 'not-allowed' 
                    : 'pointer',
                  fontWeight: 500,
                }}
              >
                {loading ? t('common.processing') : t('redeemPoints.redeem')}
              </button>
            </div>
          </form>
        )}
      </div>
    </div>
  )
}