import { useEffect, useState } from 'react'
import { Plus, Trash2, Edit2, List, Star, Server, Search } from 'lucide-react'
import api from '../lib/api'

interface User { id: number; username: string; max_connections: number; expiry_date: string | null; is_active: boolean; is_priority: boolean; created_at: string }
interface GroupedCategory { name: string; type: string; category_ids: number[]; provider_count: number }
interface CatalogEntry { id: number; category_id: number; category_name: string; type: string }
interface ProviderPref { id: number; provider_account_id: number; provider_name: string; priority: number }
interface Provider { id: number; name: string }
interface CustomCat { id: number; name: string; type: string }

const TYPE_LABELS: Record<string, string> = { live: 'Canales en directo', movie: 'Películas', series: 'Series' }

export default function Users() {
  const [users, setUsers] = useState<User[]>([])
  const [showForm, setShowForm] = useState(false)
  const [editUser, setEditUser] = useState<User | null>(null)
  const [catalogUser, setCatalogUser] = useState<User | null>(null)
  const [providerUser, setProviderUser] = useState<User | null>(null)
  const [allCategories, setAllCategories] = useState<GroupedCategory[]>([])
  const [selectedCats, setSelectedCats] = useState<Set<number>>(new Set())
  const [allCustomCats, setAllCustomCats] = useState<CustomCat[]>([])
  const [selectedCustomCats, setSelectedCustomCats] = useState<Set<number>>(new Set())
  const [catSearch, setCatSearch] = useState('')
  const [allProviders, setAllProviders] = useState<Provider[]>([])
  const [userProviderPrefs, setUserProviderPrefs] = useState<ProviderPref[]>([])

  const [form, setForm] = useState({ username: '', password: '', max_connections: 1, expiry_date: '', is_active: true, is_priority: false })

  async function load() {
    const { data } = await api.get('/users/')
    setUsers(data)
  }

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

  async function submit(e: React.FormEvent) {
    e.preventDefault()
    const payload = { ...form, expiry_date: form.expiry_date || null }
    if (editUser) {
      await api.put(`/users/${editUser.id}`, payload)
    } else {
      await api.post('/users/', payload)
    }
    resetForm()
    load()
  }

  function resetForm() {
    setForm({ username: '', password: '', max_connections: 1, expiry_date: '', is_active: true, is_priority: false })
    setShowForm(false)
    setEditUser(null)
  }

  function startEdit(u: User) {
    setForm({ username: u.username, password: '', max_connections: u.max_connections, expiry_date: u.expiry_date?.split('T')[0] || '', is_active: u.is_active, is_priority: u.is_priority })
    setEditUser(u)
    setShowForm(true)
  }

  async function del(id: number) {
    if (!confirm('¿Eliminar usuario?')) return
    await api.delete(`/users/${id}`)
    load()
  }

  async function togglePriority(u: User) {
    await api.put(`/users/${u.id}`, { is_priority: !u.is_priority })
    load()
  }

  async function openCatalog(u: User) {
    setCatalogUser(u)
    setCatSearch('')
    const [grouped, catalog, customCats, userCustomCatalog] = await Promise.all([
      api.get('/catalogs/grouped').then(r => r.data as GroupedCategory[]),
      api.get(`/users/${u.id}/catalog`).then(r => r.data as CatalogEntry[]),
      api.get('/custom-categories/').then(r => r.data as CustomCat[]),
      api.get(`/users/${u.id}/custom-catalog`).then(r => r.data as number[]),
    ])
    setAllCategories(grouped)
    setSelectedCats(new Set(catalog.map((c: CatalogEntry) => c.category_id)))
    setAllCustomCats(customCats)
    setSelectedCustomCats(new Set(userCustomCatalog))
  }

  function isGroupSelected(g: GroupedCategory): boolean {
    return g.category_ids.some(id => selectedCats.has(id))
  }

  function toggleGroup(g: GroupedCategory, checked: boolean) {
    setSelectedCats(prev => {
      const n = new Set(prev)
      if (checked) {
        g.category_ids.forEach(id => n.add(id))
      } else {
        g.category_ids.forEach(id => n.delete(id))
      }
      return n
    })
  }

  function selectAllFiltered(cats: GroupedCategory[]) {
    setSelectedCats(prev => {
      const n = new Set(prev)
      cats.forEach((g: GroupedCategory) => g.category_ids.forEach((id: number) => n.add(id)))
      return n
    })
    // Also select all filtered custom cats
    const filteredCC = allCustomCats.filter(c => !catSearch || c.name.toLowerCase().includes(catSearch.toLowerCase()))
    setSelectedCustomCats(prev => {
      const n = new Set(prev)
      filteredCC.forEach(c => n.add(c.id))
      return n
    })
  }

  function selectNoneFiltered(cats: GroupedCategory[]) {
    setSelectedCats(prev => {
      const n = new Set(prev)
      cats.forEach((g: GroupedCategory) => g.category_ids.forEach((id: number) => n.delete(id)))
      return n
    })
    const filteredCC = allCustomCats.filter(c => !catSearch || c.name.toLowerCase().includes(catSearch.toLowerCase()))
    setSelectedCustomCats(prev => {
      const n = new Set(prev)
      filteredCC.forEach(c => n.delete(c.id))
      return n
    })
  }

  async function saveCatalog() {
    if (!catalogUser) return
    await Promise.all([
      api.post(`/users/${catalogUser.id}/catalog`, Array.from(selectedCats)),
      api.post(`/users/${catalogUser.id}/custom-catalog`, Array.from(selectedCustomCats)),
    ])
    setCatalogUser(null)
  }

  async function openProviderPrefs(u: User) {
    setProviderUser(u)
    const [providers, prefs] = await Promise.all([
      api.get('/providers/').then(r => r.data as Provider[]),
      api.get(`/users/${u.id}/providers`).then(r => r.data as ProviderPref[]),
    ])
    setAllProviders(providers)
    setUserProviderPrefs(prefs)
  }

  async function addProviderPref(providerId: number) {
    if (!providerUser) return
    await api.post(`/users/${providerUser.id}/providers`, { provider_account_id: providerId, priority: userProviderPrefs.length })
    const { data } = await api.get(`/users/${providerUser.id}/providers`)
    setUserProviderPrefs(data)
  }

  async function removeProviderPref(providerId: number) {
    if (!providerUser) return
    await api.delete(`/users/${providerUser.id}/providers/${providerId}`)
    const { data } = await api.get(`/users/${providerUser.id}/providers`)
    setUserProviderPrefs(data)
  }

  const prefProviderIds = new Set(userProviderPrefs.map(p => p.provider_account_id))

  // Catalog modal filtered + grouped by type
  const filteredCats = allCategories.filter(c =>
    !catSearch || c.name.toLowerCase().includes(catSearch.toLowerCase())
  )
  const filteredCustomCats = allCustomCats.filter(c =>
    !catSearch || c.name.toLowerCase().includes(catSearch.toLowerCase())
  )
  const selectedGroupCount = allCategories.filter(g => isGroupSelected(g)).length + selectedCustomCats.size

  return (
    <div className="p-6 space-y-5">
      <div className="flex items-center justify-between">
        <h1 className="text-xl font-bold">Usuarios</h1>
        <button onClick={() => setShowForm(v => !v)} className="flex items-center gap-2 bg-primary-500 hover:bg-primary-600 px-4 py-2 rounded-lg text-sm font-medium transition-colors">
          <Plus size={16} /> Nuevo usuario
        </button>
      </div>

      {showForm && (
        <form onSubmit={submit} className="bg-dark-800 border border-dark-700 rounded-xl p-5 space-y-3">
          <h3 className="font-semibold text-sm">{editUser ? 'Editar usuario' : 'Nuevo usuario'}</h3>
          <div className="grid grid-cols-2 gap-3">
            <div>
              <label className="block text-xs text-gray-500 mb-1">Usuario</label>
              <input value={form.username} onChange={e => setForm(f => ({ ...f, username: e.target.value }))} required disabled={!!editUser}
                className="w-full bg-dark-700 border border-dark-600 rounded-lg px-3 py-2 text-sm" />
            </div>
            <div>
              <label className="block text-xs text-gray-500 mb-1">Contraseña {editUser && '(dejar vacío para no cambiar)'}</label>
              <input type="password" value={form.password} onChange={e => setForm(f => ({ ...f, password: e.target.value }))} required={!editUser}
                className="w-full bg-dark-700 border border-dark-600 rounded-lg px-3 py-2 text-sm" />
            </div>
            <div>
              <label className="block text-xs text-gray-500 mb-1">Max. conexiones simultáneas</label>
              <input type="number" min={1} value={form.max_connections} onChange={e => setForm(f => ({ ...f, max_connections: +e.target.value }))}
                className="w-full bg-dark-700 border border-dark-600 rounded-lg px-3 py-2 text-sm" />
            </div>
            <div>
              <label className="block text-xs text-gray-500 mb-1">Fecha expiración</label>
              <input type="date" value={form.expiry_date} onChange={e => setForm(f => ({ ...f, expiry_date: e.target.value }))}
                className="w-full bg-dark-700 border border-dark-600 rounded-lg px-3 py-2 text-sm" />
            </div>
            <div className="flex items-center gap-4 col-span-2">
              <label className="flex items-center gap-2 text-sm cursor-pointer">
                <input type="checkbox" checked={form.is_active} onChange={e => setForm(f => ({ ...f, is_active: e.target.checked }))} />
                Activo
              </label>
              <label className="flex items-center gap-2 text-sm cursor-pointer">
                <input type="checkbox" checked={form.is_priority} onChange={e => setForm(f => ({ ...f, is_priority: e.target.checked }))} />
                <Star size={13} className="text-yellow-400" />
                Usuario prioritario
              </label>
            </div>
          </div>
          <div className="flex gap-2">
            <button type="submit" className="bg-primary-500 hover:bg-primary-600 px-4 py-2 rounded-lg text-sm font-medium">Guardar</button>
            <button type="button" onClick={resetForm} className="bg-dark-700 hover:bg-dark-600 px-4 py-2 rounded-lg text-sm">Cancelar</button>
          </div>
        </form>
      )}

      {/* Catalog assignment modal */}
      {catalogUser && (
        <div className="fixed inset-0 bg-black/70 flex items-center justify-center z-50 p-4">
          <div className="bg-dark-800 rounded-xl border border-dark-700 w-full max-w-2xl max-h-[85vh] flex flex-col">
            <div className="p-4 border-b border-dark-700 flex items-center justify-between shrink-0">
              <div>
                <h2 className="font-semibold">Catálogo de <span className="text-primary-400">{catalogUser.username}</span></h2>
                <p className="text-xs text-gray-500 mt-0.5">{selectedGroupCount} de {allCategories.length + allCustomCats.length} categorías seleccionadas</p>
              </div>
              <button onClick={() => setCatalogUser(null)} className="text-gray-500 hover:text-white">✕</button>
            </div>

            {/* Search + bulk actions */}
            <div className="p-3 border-b border-dark-700 shrink-0 space-y-2">
              <div className="relative">
                <Search size={14} className="absolute left-3 top-1/2 -translate-y-1/2 text-gray-500" />
                <input
                  value={catSearch}
                  onChange={e => setCatSearch(e.target.value)}
                  placeholder="Buscar categoría..."
                  className="w-full bg-dark-700 border border-dark-600 rounded-lg pl-9 pr-3 py-2 text-sm focus:outline-none focus:border-primary-500"
                />
              </div>
              <div className="flex gap-2">
                <button
                  onClick={() => selectAllFiltered(filteredCats)}
                  className="text-xs px-3 py-1 rounded-lg bg-primary-900/40 hover:bg-primary-900/70 text-primary-300 border border-primary-800 transition-colors"
                >
                  Seleccionar todo
                </button>
                <button
                  onClick={() => selectNoneFiltered(filteredCats)}
                  className="text-xs px-3 py-1 rounded-lg bg-dark-700 hover:bg-dark-600 text-gray-400 border border-dark-600 transition-colors"
                >
                  Ninguna
                </button>
              </div>
            </div>

            <div className="overflow-y-auto flex-1 p-4 space-y-4">
              {(['live', 'movie', 'series'] as const).map(type => {
                const cats = filteredCats.filter(c => c.type === type)
                if (!cats.length) return null
                return (
                  <div key={type}>
                    <h3 className="text-xs text-gray-500 uppercase tracking-wider mb-2 flex items-center justify-between">
                      <span>{TYPE_LABELS[type]}</span>
                      <span className="normal-case text-gray-600">{cats.filter(g => isGroupSelected(g)).length}/{cats.length}</span>
                    </h3>
                    <div className="grid grid-cols-2 gap-1">
                      {cats.map(cat => (
                        <label
                          key={cat.name}
                          className={`flex items-center gap-2 text-sm p-2 rounded-lg cursor-pointer transition-colors ${isGroupSelected(cat) ? 'bg-primary-900/20 hover:bg-primary-900/30' : 'hover:bg-dark-700'}`}
                        >
                          <input
                            type="checkbox"
                            checked={isGroupSelected(cat)}
                            onChange={e => toggleGroup(cat, e.target.checked)}
                            className="shrink-0"
                          />
                          <span className="truncate">{cat.name}</span>
                          {cat.provider_count > 0 && (
                            <span className={`shrink-0 text-xs px-1.5 py-0.5 rounded ml-auto font-medium ${cat.provider_count > 1 ? 'bg-green-900/50 text-green-400' : 'bg-dark-600 text-gray-500'}`}>
                              {cat.provider_count}p
                            </span>
                          )}
                        </label>
                      ))}
                    </div>
                  </div>
                )
              })}
              {filteredCats.length === 0 && filteredCustomCats.length === 0 && (
                <div className="text-center text-gray-500 text-sm py-8">Sin resultados</div>
              )}

              {/* Custom categories section */}
              {filteredCustomCats.length > 0 && (
                <div>
                  <h3 className="text-xs text-gray-500 uppercase tracking-wider mb-2 flex items-center gap-2">
                    <Star size={11} className="text-yellow-400" />
                    <span>Categorías personalizadas</span>
                    <span className="normal-case text-gray-600">{filteredCustomCats.filter(c => selectedCustomCats.has(c.id)).length}/{filteredCustomCats.length}</span>
                  </h3>
                  <div className="grid grid-cols-2 gap-1">
                    {filteredCustomCats.map(cat => (
                      <label
                        key={cat.id}
                        className={`flex items-center gap-2 text-sm p-2 rounded-lg cursor-pointer transition-colors ${selectedCustomCats.has(cat.id) ? 'bg-yellow-900/20 hover:bg-yellow-900/30' : 'hover:bg-dark-700'}`}
                      >
                        <input
                          type="checkbox"
                          checked={selectedCustomCats.has(cat.id)}
                          onChange={e => {
                            setSelectedCustomCats(prev => {
                              const n = new Set(prev)
                              e.target.checked ? n.add(cat.id) : n.delete(cat.id)
                              return n
                            })
                          }}
                          className="shrink-0"
                        />
                        <span className="truncate">{cat.name}</span>
                        <Star size={10} className="shrink-0 text-yellow-500 ml-auto" />
                      </label>
                    ))}
                  </div>
                </div>
              )}
            </div>

            <div className="p-4 border-t border-dark-700 flex gap-2 justify-end shrink-0">
              <button onClick={() => setCatalogUser(null)} className="bg-dark-700 px-4 py-2 rounded-lg text-sm">Cancelar</button>
              <button onClick={saveCatalog} className="bg-primary-500 hover:bg-primary-600 px-4 py-2 rounded-lg text-sm font-medium">Guardar catálogo</button>
            </div>
          </div>
        </div>
      )}

      {/* Provider preferences modal */}
      {providerUser && (
        <div className="fixed inset-0 bg-black/70 flex items-center justify-center z-50 p-4">
          <div className="bg-dark-800 rounded-xl border border-dark-700 w-full max-w-md flex flex-col">
            <div className="p-4 border-b border-dark-700 flex items-center justify-between">
              <h2 className="font-semibold">Proveedores preferidos — <span className="text-primary-400">{providerUser.username}</span></h2>
              <button onClick={() => setProviderUser(null)} className="text-gray-500 hover:text-white">✕</button>
            </div>
            <div className="p-4 space-y-2">
              <p className="text-xs text-gray-500 mb-3">Los proveedores marcados se intentan primero al asignar un slot. Si ninguno está disponible, se usa cualquiera con slot libre.</p>
              {allProviders.map(p => {
                const isPref = prefProviderIds.has(p.id)
                return (
                  <div key={p.id} className={`flex items-center justify-between p-3 rounded-lg border ${isPref ? 'border-primary-700 bg-primary-900/20' : 'border-dark-600 bg-dark-700'}`}>
                    <span className="text-sm">{p.name}</span>
                    <button
                      onClick={() => isPref ? removeProviderPref(p.id) : addProviderPref(p.id)}
                      className={`text-xs px-3 py-1 rounded-lg font-medium transition-colors ${isPref ? 'bg-primary-600 hover:bg-red-700 text-white' : 'bg-dark-600 hover:bg-primary-700 text-gray-300 hover:text-white'}`}
                    >
                      {isPref ? 'Quitar' : 'Preferido'}
                    </button>
                  </div>
                )
              })}
              {allProviders.length === 0 && (
                <div className="text-center text-gray-500 text-sm py-4">No hay proveedores configurados</div>
              )}
            </div>
            <div className="p-4 border-t border-dark-700 flex justify-end">
              <button onClick={() => setProviderUser(null)} className="bg-dark-700 px-4 py-2 rounded-lg text-sm">Cerrar</button>
            </div>
          </div>
        </div>
      )}

      <div className="bg-dark-800 border border-dark-700 rounded-xl overflow-hidden">
        <table className="w-full text-sm">
          <thead className="border-b border-dark-700 text-xs text-gray-500">
            <tr>
              <th className="text-left px-4 py-3">Usuario</th>
              <th className="text-left px-4 py-3">Conexiones</th>
              <th className="text-left px-4 py-3">Expiración</th>
              <th className="text-left px-4 py-3">Estado</th>
              <th className="text-left px-4 py-3">Acciones</th>
            </tr>
          </thead>
          <tbody>
            {users.map(u => (
              <tr key={u.id} className="border-b border-dark-700 hover:bg-dark-700/30">
                <td className="px-4 py-3">
                  <div className="flex items-center gap-1.5">
                    {u.is_priority && <Star size={12} className="text-yellow-400 shrink-0" />}
                    <span className="font-mono">{u.username}</span>
                  </div>
                </td>
                <td className="px-4 py-3">{u.max_connections}</td>
                <td className="px-4 py-3 text-gray-400">{u.expiry_date ? new Date(u.expiry_date).toLocaleDateString('es-ES') : '—'}</td>
                <td className="px-4 py-3">
                  <span className={`text-xs px-2 py-0.5 rounded-full ${u.is_active ? 'bg-green-900/40 text-green-400' : 'bg-red-900/40 text-red-400'}`}>
                    {u.is_active ? 'Activo' : 'Inactivo'}
                  </span>
                </td>
                <td className="px-4 py-3">
                  <div className="flex items-center gap-1">
                    <button onClick={() => openCatalog(u)} title="Asignar catálogo" className="p-1.5 rounded hover:bg-dark-600 text-gray-400 hover:text-blue-400">
                      <List size={14} />
                    </button>
                    <button onClick={() => openProviderPrefs(u)} title="Proveedores preferidos" className="p-1.5 rounded hover:bg-dark-600 text-gray-400 hover:text-purple-400">
                      <Server size={14} />
                    </button>
                    <button onClick={() => togglePriority(u)} title={u.is_priority ? 'Quitar prioridad' : 'Hacer prioritario'} className={`p-1.5 rounded hover:bg-dark-600 transition-colors ${u.is_priority ? 'text-yellow-400' : 'text-gray-400 hover:text-yellow-400'}`}>
                      <Star size={14} />
                    </button>
                    <button onClick={() => startEdit(u)} title="Editar" className="p-1.5 rounded hover:bg-dark-600 text-gray-400 hover:text-yellow-400">
                      <Edit2 size={14} />
                    </button>
                    <button onClick={() => del(u.id)} title="Eliminar" className="p-1.5 rounded hover:bg-dark-600 text-gray-400 hover:text-red-400">
                      <Trash2 size={14} />
                    </button>
                  </div>
                </td>
              </tr>
            ))}
            {users.length === 0 && (
              <tr><td colSpan={5} className="px-4 py-8 text-center text-gray-500">No hay usuarios</td></tr>
            )}
          </tbody>
        </table>
      </div>
    </div>
  )
}