import React, { useCallback, useEffect, useRef, useState } from 'react'
import { createPortal } from 'react-dom'
import ShareToast from '../ui/ShareToast'

/* ── Platform share URLs ─────────────────────────────────────────────────── */
function facebookUrl(url) {
  return `https://www.facebook.com/sharer/sharer.php?u=${encodeURIComponent(url)}`
}
function twitterUrl(url, title) {
  return `https://twitter.com/intent/tweet?url=${encodeURIComponent(url)}&text=${encodeURIComponent(title)}`
}
function pinterestUrl(url, imageUrl, title) {
  return `https://pinterest.com/pin/create/button/?url=${encodeURIComponent(url)}&media=${encodeURIComponent(imageUrl)}&description=${encodeURIComponent(title)}`
}
function emailUrl(url, title) {
  return `mailto:?subject=${encodeURIComponent(title)}&body=${encodeURIComponent(url)}`
}

/* ── Icons ────────────────────────────────────────────────────────────────── */
function CopyIcon() {
  return (
    <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" strokeWidth={1.5} stroke="currentColor" className="h-5 w-5">
      <path strokeLinecap="round" strokeLinejoin="round" d="M15.75 17.25v3.375c0 .621-.504 1.125-1.125 1.125h-9.75a1.125 1.125 0 0 1-1.125-1.125V7.875c0-.621.504-1.125 1.125-1.125H6.75a9.06 9.06 0 0 1 1.5.124m7.5 10.376h3.375c.621 0 1.125-.504 1.125-1.125V11.25c0-4.46-3.243-8.161-7.5-8.876a9.06 9.06 0 0 0-1.5-.124H9.375c-.621 0-1.125.504-1.125 1.125v3.5m7.5 10.375H9.375a1.125 1.125 0 0 1-1.125-1.125v-9.25m12 6.625v-1.875a3.375 3.375 0 0 0-3.375-3.375h-1.5a1.125 1.125 0 0 1-1.125-1.125v-1.5a3.375 3.375 0 0 0-3.375-3.375H9.75" />
    </svg>
  )
}

function CheckIcon() {
  return (
    <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 20 20" fill="currentColor" className="h-5 w-5 text-emerald-400">
      <path fillRule="evenodd" d="M16.704 4.153a.75.75 0 0 1 .143 1.052l-8 10.5a.75.75 0 0 1-1.127.075l-4.5-4.5a.75.75 0 0 1 1.06-1.06l3.894 3.893 7.48-9.817a.75.75 0 0 1 1.05-.143Z" clipRule="evenodd" />
    </svg>
  )
}

function FacebookIcon() {
  return (
    <svg viewBox="0 0 24 24" fill="currentColor" className="h-5 w-5">
      <path d="M22 12c0-5.523-4.477-10-10-10S2 6.477 2 12c0 4.991 3.657 9.128 8.438 9.878v-6.987h-2.54V12h2.54V9.797c0-2.506 1.492-3.89 3.777-3.89 1.094 0 2.238.195 2.238.195v2.46h-1.26c-1.243 0-1.63.771-1.63 1.562V12h2.773l-.443 2.89h-2.33v6.988C18.343 21.128 22 16.991 22 12Z" />
    </svg>
  )
}

function XTwitterIcon() {
  return (
    <svg viewBox="0 0 24 24" fill="currentColor" className="h-5 w-5">
      <path d="M18.244 2.25h3.308l-7.227 8.26 8.502 11.24H16.17l-5.214-6.817L4.99 21.75H1.68l7.73-8.835L1.254 2.25H8.08l4.713 6.231 5.45-6.231Zm-1.161 17.52h1.833L7.084 4.126H5.117L17.083 19.77Z" />
    </svg>
  )
}

function PinterestIcon() {
  return (
    <svg viewBox="0 0 24 24" fill="currentColor" className="h-5 w-5">
      <path d="M12 2C6.477 2 2 6.477 2 12c0 4.236 2.636 7.855 6.356 9.312-.088-.791-.167-2.005.035-2.868.181-.78 1.172-4.97 1.172-4.97s-.299-.598-.299-1.482c0-1.388.806-2.425 1.808-2.425.853 0 1.265.64 1.265 1.408 0 .858-.546 2.14-.828 3.33-.236.995.5 1.807 1.482 1.807 1.778 0 3.144-1.874 3.144-4.58 0-2.393-1.72-4.068-4.177-4.068-2.845 0-4.515 2.135-4.515 4.34 0 .859.331 1.781.745 2.282a.3.3 0 0 1 .069.288l-.278 1.133c-.044.183-.145.222-.335.134-1.249-.581-2.03-2.407-2.03-3.874 0-3.154 2.292-6.052 6.608-6.052 3.469 0 6.165 2.472 6.165 5.776 0 3.447-2.173 6.22-5.19 6.22-1.013 0-1.965-.527-2.291-1.148l-.623 2.378c-.226.869-.835 1.958-1.244 2.621.937.29 1.931.446 2.962.446 5.523 0 10-4.477 10-10S17.523 2 12 2Z" />
    </svg>
  )
}

function EmailIcon() {
  return (
    <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" strokeWidth={1.5} stroke="currentColor" className="h-5 w-5">
      <path strokeLinecap="round" strokeLinejoin="round" d="M21.75 6.75v10.5a2.25 2.25 0 0 1-2.25 2.25h-15a2.25 2.25 0 0 1-2.25-2.25V6.75m19.5 0A2.25 2.25 0 0 0 19.5 4.5h-15a2.25 2.25 0 0 0-2.25 2.25m19.5 0v.243a2.25 2.25 0 0 1-1.07 1.916l-7.5 4.615a2.25 2.25 0 0 1-2.36 0L3.32 8.91a2.25 2.25 0 0 1-1.07-1.916V6.75" />
    </svg>
  )
}

function EmbedIcon() {
  return (
    <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" strokeWidth={1.5} stroke="currentColor" className="h-5 w-5">
      <path strokeLinecap="round" strokeLinejoin="round" d="M17.25 6.75 22.5 12l-5.25 5.25m-10.5 0L1.5 12l5.25-5.25m7.5-3-4.5 16.5" />
    </svg>
  )
}

function CloseIcon() {
  return (
    <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" strokeWidth={2} stroke="currentColor" className="h-5 w-5">
      <path strokeLinecap="round" strokeLinejoin="round" d="M6 18 18 6M6 6l12 12" />
    </svg>
  )
}

/* ── Helpers ──────────────────────────────────────────────────────────────── */
function openShareWindow(url) {
  window.open(url, '_blank', 'noopener,noreferrer,width=600,height=500')
}

function trackShare(artworkId, platform) {
  const csrfToken = document.querySelector('meta[name="csrf-token"]')?.getAttribute('content')
  fetch(`/api/artworks/${artworkId}/share`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json', 'X-CSRF-TOKEN': csrfToken || '' },
    credentials: 'same-origin',
    body: JSON.stringify({ platform }),
  }).catch(() => {})
}

/* ── Main component ──────────────────────────────────────────────────────── */

/**
 * ArtworkShareModal
 *
 * Props:
 *   open      – boolean, whether modal is visible
 *   onClose   – callback to close modal
 *   artwork   – artwork object (id, title, description, thumbs, canonical_url, …)
 *   shareUrl  – canonical share URL
 */
export default function ArtworkShareModal({ open, onClose, artwork, shareUrl }) {
  const backdropRef = useRef(null)
  const [linkCopied, setLinkCopied] = useState(false)
  const [embedCopied, setEmbedCopied] = useState(false)
  const [showEmbed, setShowEmbed] = useState(false)
  const [toastVisible, setToastVisible] = useState(false)
  const [toastMessage, setToastMessage] = useState('')

  const url = shareUrl || artwork?.canonical_url || (typeof window !== 'undefined' ? window.location.href : '#')
  const title = artwork?.title || 'Artwork'
  const imageUrl = artwork?.thumbs?.xl?.url || artwork?.thumbs?.lg?.url || artwork?.thumbs?.md?.url || ''
  const thumbMdUrl = artwork?.thumbs?.md?.url || imageUrl

  const embedCode = `<a href="${url}">\n  <img src="${thumbMdUrl}" alt="${title.replace(/"/g, '&quot;')}" />\n</a>`

  // Lock body scroll when open
  useEffect(() => {
    if (open) {
      document.body.style.overflow = 'hidden'
      return () => { document.body.style.overflow = '' }
    }
  }, [open])

  // Close on Escape
  useEffect(() => {
    if (!open) return
    const handler = (e) => { if (e.key === 'Escape') onClose() }
    window.addEventListener('keydown', handler)
    return () => window.removeEventListener('keydown', handler)
  }, [open, onClose])

  // Reset state when re-opening
  useEffect(() => {
    if (open) {
      setLinkCopied(false)
      setEmbedCopied(false)
      setShowEmbed(false)
    }
  }, [open])

  const showToast = useCallback((msg) => {
    setToastMessage(msg)
    setToastVisible(true)
  }, [])

  const handleCopyLink = async () => {
    try {
      await navigator.clipboard.writeText(url)
      setLinkCopied(true)
      showToast('Link copied!')
      trackShare(artwork?.id, 'copy')
      setTimeout(() => setLinkCopied(false), 2500)
    } catch { /* noop */ }
  }

  const handleCopyEmbed = async () => {
    try {
      await navigator.clipboard.writeText(embedCode)
      setEmbedCopied(true)
      showToast('Embed code copied!')
      trackShare(artwork?.id, 'embed')
      setTimeout(() => setEmbedCopied(false), 2500)
    } catch { /* noop */ }
  }

  const handlePlatformShare = (platform, shareLink) => {
    openShareWindow(shareLink)
    trackShare(artwork?.id, platform)
    onClose()
  }

  if (!open) return null

  const SHARE_OPTIONS = [
    {
      label: linkCopied ? 'Copied!' : 'Copy Link',
      icon: linkCopied ? <CheckIcon /> : <CopyIcon />,
      onClick: handleCopyLink,
      className: linkCopied
        ? 'border-emerald-500/40 bg-emerald-500/15 text-emerald-400'
        : 'border-white/[0.08] bg-white/[0.04] text-white/70 hover:border-white/[0.15] hover:bg-white/[0.07] hover:text-white',
    },
    {
      label: 'Facebook',
      icon: <FacebookIcon />,
      onClick: () => handlePlatformShare('facebook', facebookUrl(url)),
      className: 'border-white/[0.08] bg-white/[0.04] text-white/70 hover:border-[#1877F2]/40 hover:bg-[#1877F2]/15 hover:text-[#1877F2]',
    },
    {
      label: 'X (Twitter)',
      icon: <XTwitterIcon />,
      onClick: () => handlePlatformShare('twitter', twitterUrl(url, title)),
      className: 'border-white/[0.08] bg-white/[0.04] text-white/70 hover:border-white/30 hover:bg-white/[0.10] hover:text-white',
    },
    {
      label: 'Pinterest',
      icon: <PinterestIcon />,
      onClick: () => handlePlatformShare('pinterest', pinterestUrl(url, imageUrl, title)),
      className: 'border-white/[0.08] bg-white/[0.04] text-white/70 hover:border-[#E60023]/40 hover:bg-[#E60023]/15 hover:text-[#E60023]',
    },
    {
      label: 'Email',
      icon: <EmailIcon />,
      onClick: () => { window.location.href = emailUrl(url, title); trackShare(artwork?.id, 'email') },
      className: 'border-white/[0.08] bg-white/[0.04] text-white/70 hover:border-white/[0.15] hover:bg-white/[0.07] hover:text-white',
    },
  ]

  return createPortal(
    <>
      {/* Backdrop */}
      <div
        ref={backdropRef}
        onClick={(e) => { if (e.target === backdropRef.current) onClose() }}
        className="fixed inset-0 z-[9999] flex items-center justify-center bg-black/60 backdrop-blur-sm p-4"
        role="dialog"
        aria-modal="true"
        aria-label="Share this artwork"
      >
        {/* Modal container — glassmorphism */}
        <div className="w-full max-w-md rounded-2xl border border-nova-700/50 bg-nova-900/80 shadow-2xl backdrop-blur-xl">
          {/* Header */}
          <div className="flex items-center justify-between border-b border-white/[0.06] px-6 py-4">
            <h3 className="text-base font-semibold text-white">Share this artwork</h3>
            <button
              type="button"
              onClick={onClose}
              className="rounded-lg p-1.5 text-white/40 transition hover:bg-white/[0.06] hover:text-white/70"
              aria-label="Close share dialog"
            >
              <CloseIcon />
            </button>
          </div>

          {/* Artwork preview */}
          {thumbMdUrl && (
            <div className="flex items-center gap-3 border-b border-white/[0.06] px-6 py-3">
              <img
                src={thumbMdUrl}
                alt={title}
                className="h-14 w-14 rounded-lg object-cover"
                loading="lazy"
              />
              <div className="min-w-0 flex-1">
                <p className="truncate text-sm font-medium text-white">{title}</p>
                {artwork?.user?.username && (
                  <p className="truncate text-xs text-white/50">by {artwork.user.username}</p>
                )}
              </div>
            </div>
          )}

          {/* Share buttons grid */}
          <div className="grid grid-cols-3 gap-2.5 px-6 py-5 sm:grid-cols-5">
            {SHARE_OPTIONS.map((opt) => (
              <button
                key={opt.label}
                type="button"
                onClick={opt.onClick}
                className={[
                  'flex flex-col items-center gap-1.5 rounded-xl border px-2 py-3 text-xs font-medium transition-all duration-200',
                  opt.className,
                ].join(' ')}
              >
                {opt.icon}
                <span className="truncate">{opt.label}</span>
              </button>
            ))}
          </div>

          {/* Embed section */}
          <div className="border-t border-white/[0.06] px-6 py-4">
            <button
              type="button"
              onClick={() => setShowEmbed(!showEmbed)}
              className="flex items-center gap-2 text-sm font-medium text-white/60 transition hover:text-white/80"
            >
              <EmbedIcon />
              {showEmbed ? 'Hide Embed Code' : 'Embed Code'}
              <svg
                xmlns="http://www.w3.org/2000/svg"
                viewBox="0 0 16 16"
                fill="currentColor"
                className={`h-3.5 w-3.5 transition-transform duration-200 ${showEmbed ? 'rotate-180' : ''}`}
              >
                <path fillRule="evenodd" d="M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z" clipRule="evenodd" />
              </svg>
            </button>

            {showEmbed && (
              <div className="mt-3 space-y-2">
                <textarea
                  readOnly
                  value={embedCode}
                  rows={3}
                  className="w-full resize-none rounded-xl border border-white/[0.08] bg-white/[0.03] px-4 py-3 font-mono text-xs text-white/70 outline-none focus:border-white/[0.15]"
                  onClick={(e) => e.target.select()}
                />
                <button
                  type="button"
                  onClick={handleCopyEmbed}
                  className={[
                    'inline-flex items-center gap-1.5 rounded-full border px-4 py-1.5 text-xs font-medium transition-all duration-200',
                    embedCopied
                      ? 'border-emerald-500/40 bg-emerald-500/15 text-emerald-400'
                      : 'border-white/[0.08] bg-white/[0.04] text-white/60 hover:border-white/[0.15] hover:text-white/80',
                  ].join(' ')}
                >
                  {embedCopied ? <CheckIcon /> : <CopyIcon />}
                  {embedCopied ? 'Copied!' : 'Copy Embed'}
                </button>
              </div>
            )}
          </div>
        </div>
      </div>

      {/* Toast */}
      <ShareToast
        message={toastMessage}
        visible={toastVisible}
        onHide={() => setToastVisible(false)}
      />
    </>,
    document.body,
  )
}