import React, { useCallback, useEffect, useState } from 'react'
import { Button } from '@/components/ui/button'
import { Input } from '@/components/ui/input'
import {
  ChevronRight, Clock3, FolderOpen, Grid2X2, List as ListIcon,
  LoaderCircle, Search, Upload,
} from 'lucide-react'
import FileList from './FileList'
import FileGrid from './FileGrid'
import Banner from './StatusBanner'
import { headerNames } from '@/config/navigation'
import ContextActions, {fileOptions} from './ContextActions'

export default function DriveExplorer({ controller, user }) {
  const {
    view, setParent, trail, items, stats, query, setQuery, search, loading,
    error, setError, note, setNote, layout, setLayout, sort, setSort,
    display, goRoot, openEntry, startAction, performItemAction, filesInput, isTrash, canWrite, activeSpace,
  } = controller

  const [context, setContext] = useState(null)
  const closeContext = useCallback(() => setContext(null), [])
  const openContext = (item,x,y) => {
    const options=fileOptions(item,isTrash,view==='shared')
    if (options.length) setContext({item,x,y,options})
  }
  useEffect(() => {
    if (context && !display.some(item => item.id === context.item.id && item.space_id === context.item.space_id)) closeContext()
  }, [display, context, closeContext])
  useEffect(() => { closeContext() }, [view, activeSpace?.id, closeContext])

  // In "Partagés avec moi", space statistics belong to the last selected
  // space. Count the displayed shared files and folders instead.
  const visibleCounts = loading ? null : view === 'shared'
    ? { folders: display.filter(item => item.is_folder).length, files: display.filter(item => !item.is_folder).length }
    : view === 'files' ? stats : null

  const title = search
    ? `« ${search} »`
    : trail.length && !search ? trail.at(-1)?.name : view === 'files' ? (activeSpace?.display_name || headerNames[view]) : (view === 'shared' ? 'Partagés avec moi' : headerNames[view])

  return (
    <section className="flex min-h-0 flex-1 flex-col overflow-hidden px-4 pb-4 pt-6 sm:px-7 sm:pb-7">
      <div className="mb-4 flex items-center gap-2 lg:hidden">
        <Search className="size-4 text-muted-foreground" />
        <Input value={query} onChange={event => setQuery(event.target.value)} placeholder="Rechercher dans mes fichiers…" aria-label="Rechercher" />
      </div>

      <div className="mb-5 flex flex-wrap items-end justify-between gap-3">
        <div className="min-w-0">
          {!isTrash && <div className="mb-2 flex items-center gap-1.5 text-xs text-muted-foreground">
            <button onClick={goRoot} className="rounded px-1 py-1 hover:bg-muted">{view === 'shared' ? 'Partagés avec moi' : activeSpace?.is_private ? 'Mes fichiers' : activeSpace?.display_name || 'Mes fichiers'}</button>
            {(view === 'files' || view === 'shared') && !search && trail.map(folder => (
              <React.Fragment key={folder.id}>
                <ChevronRight className="size-3.5" />
                <button className="max-w-28 truncate rounded px-1 py-1 hover:bg-muted" onClick={() => setParent(folder.id)}>{folder.name}</button>
              </React.Fragment>
            ))}
            {view !== 'files' && view !== 'shared' && <>
              <ChevronRight className="size-3.5" />
              <span>{headerNames[view]}</span>
            </>}
          </div>}
          <h1 className="text-2xl font-semibold tracking-tight">{title}</h1>
          {isTrash && (
            <p className="mt-2 flex items-center gap-2 text-xs text-muted-foreground">
              <Clock3 className="size-3.5 shrink-0" aria-hidden="true" />
              Les éléments de la corbeille sont supprimés définitivement après 5 jours.
            </p>
          )}
          <p className="mt-1 text-sm text-muted-foreground">
            {loading ? 'Chargement…' : `${items.length} élément${items.length > 1 ? 's' : ''}`}
            {!canWrite ? ' · lecture seule' : ''}
          </p>
        </div>

        <div className="flex items-center gap-1.5">
          <span className="mr-1 hidden text-xs text-muted-foreground sm:inline">Trier :</span>
          <select value={sort} onChange={event => setSort(event.target.value)} className="h-9 rounded-lg border bg-card px-2 text-xs outline-none sm:text-sm">
            <option value="name">Nom</option>
            <option value="date">Date</option>
            <option value="size">Taille</option>
          </select>
          <div className="ml-1 flex rounded-lg border bg-card p-0.5">
            <Button size="icon-sm" variant={layout === 'list' ? 'secondary' : 'ghost'} aria-label="Liste" onClick={() => setLayout('list')}>
              <ListIcon />
            </Button>
            <Button size="icon-sm" variant={layout === 'grid' ? 'secondary' : 'ghost'} aria-label="Grille" onClick={() => setLayout('grid')}>
              <Grid2X2 />
            </Button>
          </div>
        </div>
      </div>

      {error && <div className="mb-3"><Banner text={error} close={() => setError('')} /></div>}
      {note && <div className="mb-3"><Banner text={note} close={() => setNote('')} /></div>}

      <div className="min-h-0 flex-1 overflow-y-auto rounded-2xl border bg-card shadow-sm">
        {loading ? (
          <div className="flex h-full min-h-72 items-center justify-center gap-3 text-sm text-muted-foreground">
            <LoaderCircle className="size-5 animate-spin" /> Chargement des fichiers…
          </div>
        ) : !display.length ? (
          <div className="flex min-h-80 flex-col items-center justify-center px-5 text-center">
            <div className="mb-4 grid size-20 place-items-center rounded-3xl bg-muted">
              <FolderOpen className="size-9 text-primary" />
            </div>
            <h3 className="text-lg font-semibold">
              {isTrash ? 'La corbeille est vide' : search ? 'Aucun résultat' : view === 'shared' ? 'Aucun fichier partagé' : 'Cet espace est vide'}
            </h3>
            <p className="mt-2 max-w-sm text-sm leading-relaxed text-muted-foreground">
              {isTrash
                ? 'Les fichiers et dossiers supprimés apparaîtront ici.'
                : search ? 'Essaie un autre nom de fichier.'
                  : view === 'shared' ? 'Les éléments que d’autres utilisateurs partagent avec toi apparaîtront ici.' : 'Importe tes premiers fichiers ou crée un dossier pour commencer à organiser ton espace.'}
            </p>
            {!isTrash && !search && canWrite && (
              <Button className="mt-5" onClick={() => filesInput.current?.click()}>
                <Upload /> Importer des fichiers
              </Button>
            )}
          </div>
        ) : layout === 'list' ? (
          <FileList items={display} user={user} onOpen={isTrash ? () => {} : openEntry} onActions={startAction} onContext={openContext} />
        ) : (
          <FileGrid items={display} onOpen={isTrash ? () => {} : openEntry} onActions={startAction} onContext={openContext} />
        )}
      </div>

      <ContextActions menu={context && {...context, options:fileOptions(context.item,isTrash,view==='shared')}} onClose={closeContext}
        onChoose={type => performItemAction(context.item,type)} />
      <footer className="flex justify-between gap-2 px-1 pt-3 text-[11px] text-muted-foreground">
        <span className="hidden md:inline">Clic droit sur un élément pour les actions.</span>
        <span>{visibleCounts ? `${visibleCounts.folders} dossier${visibleCounts.folders === 1 ? '' : 's'} · ${visibleCounts.files} fichier${visibleCounts.files === 1 ? '' : 's'}` : ''}</span>
      </footer>
    </section>
  )
}