import { useEffect, useRef, useState } from 'react'
import api from '../lib/api'
import { Upload, Trash2, ImageIcon, Info } from 'lucide-react'

export default function Settings() {
  const [hasImage, setHasImage] = useState(false)
  const [imageUrl, setImageUrl] = useState('')
  const [uploading, setUploading] = useState(false)
  const [dragging, setDragging] = useState(false)
  const fileRef = useRef<HTMLInputElement>(null)

  const checkImage = async () => {
    try {
      const token = localStorage.getItem('token')
      const res = await fetch('/api/admin/settings/blocked-image', {
        headers: { Authorization: `Bearer ${token}` },
      })
      if (res.ok) {
        setHasImage(true)
        // Use the static file URL (no auth needed) for the <img> tag
        setImageUrl('/panel/blocked_image.jpg?t=' + Date.now())
      } else {
        setHasImage(false)
        setImageUrl('')
      }
    } catch {
      setHasImage(false)
    }
  }

  useEffect(() => { checkImage() }, [])

  const upload = async (file: File) => {
    if (!file.type.startsWith('image/')) {
      alert('Solo se permiten imágenes (JPEG, PNG, WebP, GIF)')
      return
    }
    setUploading(true)
    try {
      const form = new FormData()
      form.append('file', file)
      await api.post('/settings/blocked-image', form, {
        headers: { 'Content-Type': 'multipart/form-data' },
      })
      await checkImage()
    } catch (e: any) {
      alert('Error al subir la imagen: ' + (e.response?.data?.detail || e.message))
    } finally {
      setUploading(false)
    }
  }

  const handleFileChange = (e: React.ChangeEvent<HTMLInputElement>) => {
    const file = e.target.files?.[0]
    if (file) upload(file)
    e.target.value = ''
  }

  const handleDrop = (e: React.DragEvent) => {
    e.preventDefault()
    setDragging(false)
    const file = e.dataTransfer.files[0]
    if (file) upload(file)
  }

  const deleteImage = async () => {
    if (!confirm('¿Eliminar la imagen de bloqueo?')) return
    await api.delete('/settings/blocked-image')
    setHasImage(false)
    setImageUrl('')
  }

  return (
    <div className="p-6 max-w-2xl space-y-6">
      <h1 className="text-xl font-bold">Ajustes</h1>

      {/* Blocked image section */}
      <div className="bg-dark-800 rounded-xl p-6 space-y-4">
        <div>
          <h2 className="font-semibold text-base flex items-center gap-2">
            <ImageIcon size={18} className="text-primary-400" />
            Imagen de conexión bloqueada
          </h2>
          <p className="text-sm text-gray-400 mt-1">
            Esta imagen se mostrará como canal de vídeo cuando un usuario intente reproducir
            en un segundo dispositivo habiendo alcanzado su límite de conexiones simultáneas.
          </p>
        </div>

        <div className="flex items-start gap-2 text-xs text-blue-400 bg-blue-500/10 rounded-lg px-3 py-2">
          <Info size={13} className="mt-0.5 shrink-0" />
          <span>
            El zapping normal (cambiar de canal en el mismo dispositivo) sigue funcionando
            sin interrupciones. La imagen solo aparece cuando se conecta un segundo dispositivo
            diferente con la misma cuenta.
          </span>
        </div>

        {/* Upload area */}
        <div
          onDragOver={e => { e.preventDefault(); setDragging(true) }}
          onDragLeave={() => setDragging(false)}
          onDrop={handleDrop}
          onClick={() => !uploading && fileRef.current?.click()}
          className={`
            relative border-2 border-dashed rounded-xl cursor-pointer transition-colors
            ${dragging ? 'border-primary-400 bg-primary-500/10' : 'border-dark-600 hover:border-dark-500'}
          `}
        >
          <input ref={fileRef} type="file" accept="image/*" className="hidden" onChange={handleFileChange} />

          {hasImage && imageUrl ? (
            <div className="relative">
              <img
                src={imageUrl}
                alt="Blocked image"
                className="w-full rounded-xl object-contain max-h-72"
              />
              <div className="absolute inset-0 bg-black/40 opacity-0 hover:opacity-100 transition-opacity rounded-xl flex items-center justify-center">
                <span className="text-white text-sm font-medium">Haz clic para cambiar</span>
              </div>
            </div>
          ) : (
            <div className="py-12 flex flex-col items-center gap-3 text-gray-500">
              <Upload size={32} className={dragging ? 'text-primary-400' : ''} />
              <div className="text-center">
                <p className="font-medium text-sm">Arrastra una imagen o haz clic para subir</p>
                <p className="text-xs mt-1">JPEG, PNG, WebP o GIF · máx. 10 MB</p>
              </div>
            </div>
          )}

          {uploading && (
            <div className="absolute inset-0 bg-dark-900/80 rounded-xl flex items-center justify-center">
              <div className="text-sm text-primary-400">Subiendo...</div>
            </div>
          )}
        </div>

        {hasImage && (
          <div className="flex justify-end">
            <button
              onClick={deleteImage}
              className="flex items-center gap-2 px-3 py-1.5 bg-red-500/20 text-red-400 hover:bg-red-500/30 rounded-lg text-sm transition-colors"
            >
              <Trash2 size={14} /> Eliminar imagen
            </button>
          </div>
        )}
      </div>
    </div>
  )
}