import React, { useEffect, useRef, useState } from 'react';
import { Camera, ExternalLink, Globe2, Instagram, Linkedin, Loader2, Save, UserRound, Youtube } from 'lucide-react';
import { useAuth } from '../context/AuthContext';
import { Profile, ProfileInput, instructorApi, profileApi } from '../services/api';
import { CourseCoverImage } from '../components/CourseCoverImage';
import { useToast } from '../context/ToastContext';
import { useNavigate } from 'react-router-dom';

const emptyProfile = (user: { id: string; email: string; name: string; role: string }): Profile => ({
  id: user.id,
  email: user.email,
  name: user.name,
  role: user.role === 'superadmin' ? 'admin' : user.role === 'professor' ? 'instructor' : 'student',
  avatarImageUrl: null,
  headline: '',
  bio: '',
  websiteUrl: null,
  linkedinUrl: null,
  instagramUrl: null,
  youtubeUrl: null,
  isPublic: true,
});

const inputClass = 'w-full rounded-xl border border-white/10 bg-zinc-900 px-4 py-3 text-sm text-white outline-none transition focus:border-orange-500/70 focus:ring-2 focus:ring-orange-500/15';

export const ProfilePage: React.FC = () => {
  const { user, updateCurrentUser } = useAuth();
  const { showToast } = useToast();
  const navigate = useNavigate();
  const fileInput = useRef<HTMLInputElement>(null);
  const [profile, setProfile] = useState<Profile | null>(null);
  const [isLoading, setIsLoading] = useState(true);
  const [isSaving, setIsSaving] = useState(false);
  const [isUploading, setIsUploading] = useState(false);

  const canPublishProfile = user?.role === 'professor' || user?.role === 'superadmin';

  useEffect(() => {
    if (!user) return;
    profileApi.me()
      .then((response) => setProfile(response.data))
      .catch(() => {
        setProfile(emptyProfile(user));
        showToast('Não foi possível carregar todos os dados do perfil.', 'error');
      })
      .finally(() => setIsLoading(false));
  }, [showToast, user]);

  if (isLoading || !profile || !user) {
    return <main className="min-h-[65vh] pt-32 flex items-center justify-center"><Loader2 className="h-8 w-8 animate-spin text-orange-400" /></main>;
  }

  const update = <K extends keyof Profile>(key: K, value: Profile[K]) => setProfile((current) => current ? { ...current, [key]: value } : current);

  const uploadAvatar = async (file?: File) => {
    if (!file) return;
    if (!file.type.startsWith('image/')) {
      showToast('Selecione uma imagem JPG, PNG ou WebP.', 'error');
      return;
    }
    setIsUploading(true);
    try {
      const response = await instructorApi.uploadCover(file);
      update('avatarImageUrl', response.data.coverImageUrl);
      showToast('Foto enviada. Salve o perfil para publicar a alteração.', 'success');
    } catch {
      showToast('Não foi possível enviar a foto.', 'error');
    } finally {
      setIsUploading(false);
    }
  };

  const save = async (event: React.FormEvent) => {
    event.preventDefault();
    const input: ProfileInput = {
      name: profile.name,
      avatarImageUrl: profile.avatarImageUrl,
      headline: profile.headline,
      bio: profile.bio,
      websiteUrl: profile.websiteUrl,
      linkedinUrl: profile.linkedinUrl,
      instagramUrl: profile.instagramUrl,
      youtubeUrl: profile.youtubeUrl,
      isPublic: profile.isPublic,
    };
    setIsSaving(true);
    try {
      const response = await profileApi.update(input);
      setProfile(response.data);
      updateCurrentUser({ id: user.id, email: user.email, name: response.data.name, role: response.data.role });
      showToast('Perfil salvo com sucesso.', 'success');
    } catch {
      showToast('Não foi possível salvar o perfil. Verifique os links informados.', 'error');
    } finally {
      setIsSaving(false);
    }
  };

  return (
    <main className="mx-auto min-h-screen w-full max-w-5xl px-5 pb-20 pt-28 sm:px-8">
      <div className="mb-8 flex flex-col justify-between gap-5 sm:flex-row sm:items-end">
        <div>
          <p className="mb-2 text-xs font-bold uppercase tracking-[0.18em] text-orange-400">Sua conta</p>
          <h1 className="text-3xl font-bold tracking-tight text-white sm:text-4xl">Meu perfil</h1>
          <p className="mt-2 max-w-xl text-sm text-gray-400">{canPublishProfile ? 'Apresente sua experiência e conecte os alunos aos seus cursos.' : 'Mantenha seus dados pessoais atualizados.'}</p>
        </div>
        {canPublishProfile && profile.isPublic && <button onClick={() => navigate(`/instrutores/${user.id}`)} className="inline-flex items-center justify-center gap-2 rounded-xl border border-white/15 bg-white/5 px-4 py-3 text-sm font-semibold text-white transition hover:bg-white/10"><ExternalLink className="h-4 w-4" /> Ver perfil público</button>}
      </div>

      <form onSubmit={save} className="overflow-hidden rounded-3xl border border-white/10 bg-zinc-950/80 shadow-2xl shadow-black/30">
        <section className="border-b border-white/10 bg-gradient-to-r from-orange-500/15 via-zinc-950 to-zinc-950 p-6 sm:p-8">
          <div className="flex flex-col gap-5 sm:flex-row sm:items-center">
            <div className="relative h-28 w-28 shrink-0 overflow-hidden rounded-full border-4 border-zinc-950 bg-zinc-900 shadow-xl">
              {profile.avatarImageUrl ? <CourseCoverImage source={profile.avatarImageUrl} alt={`Foto de ${profile.name}`} className="h-full w-full object-cover" /> : <div className="flex h-full w-full items-center justify-center bg-orange-500/15"><UserRound className="h-11 w-11 text-orange-300" /></div>}
              {canPublishProfile && <button type="button" disabled={isUploading} onClick={() => fileInput.current?.click()} className="absolute inset-x-0 bottom-0 flex h-9 items-center justify-center bg-black/70 text-xs font-semibold text-white transition hover:bg-black/90 disabled:opacity-60">{isUploading ? <Loader2 className="h-4 w-4 animate-spin" /> : <><Camera className="mr-1.5 h-3.5 w-3.5" /> Alterar</>}</button>}
            </div>
            <div><h2 className="text-xl font-bold text-white">{profile.name}</h2><p className="mt-1 text-sm text-gray-400">{user.email}</p>{canPublishProfile && <p className="mt-3 text-xs text-orange-200/80">A foto e a apresentação ficam visíveis no seu perfil público.</p>}</div>
          </div>
          <input ref={fileInput} type="file" accept="image/jpeg,image/png,image/webp" className="hidden" onChange={(event) => { void uploadAvatar(event.target.files?.[0]); event.currentTarget.value = ''; }} />
        </section>

        <div className="grid gap-8 p-6 sm:p-8 lg:grid-cols-[1fr_0.8fr]">
          <section className="space-y-5">
            <label className="block"><span className="mb-2 block text-sm font-semibold text-white">Nome</span><input value={profile.name} onChange={(event) => update('name', event.target.value)} className={inputClass} maxLength={120} required /></label>
            {canPublishProfile && <>
              <label className="block"><span className="mb-2 block text-sm font-semibold text-white">Título profissional</span><input value={profile.headline} onChange={(event) => update('headline', event.target.value)} placeholder="Ex.: Especialista em crescimento e mídia paga" className={inputClass} maxLength={180} /></label>
              <label className="block"><span className="mb-2 block text-sm font-semibold text-white">Sobre você</span><textarea value={profile.bio} onChange={(event) => update('bio', event.target.value)} placeholder="Conte brevemente sua experiência e o que os alunos podem esperar aprender com você." className={`${inputClass} min-h-40 resize-y`} maxLength={3000} /></label>
            </>}
          </section>

          {canPublishProfile && <section className="rounded-2xl border border-white/10 bg-black/30 p-5 sm:p-6"><div className="mb-5"><h2 className="font-bold text-white">Links e visibilidade</h2><p className="mt-1 text-xs leading-relaxed text-gray-500">Use links completos, começando com https://.</p></div><div className="space-y-4"><UrlField icon={<Globe2 />} label="Site" value={profile.websiteUrl} onChange={(value) => update('websiteUrl', value || null)} placeholder="https://seusite.com" /><UrlField icon={<Linkedin />} label="LinkedIn" value={profile.linkedinUrl} onChange={(value) => update('linkedinUrl', value || null)} placeholder="https://linkedin.com/in/seu-perfil" /><UrlField icon={<Instagram />} label="Instagram" value={profile.instagramUrl} onChange={(value) => update('instagramUrl', value || null)} placeholder="https://instagram.com/seu-perfil" /><UrlField icon={<Youtube />} label="YouTube" value={profile.youtubeUrl} onChange={(value) => update('youtubeUrl', value || null)} placeholder="https://youtube.com/@seu-canal" /></div><label className="mt-6 flex cursor-pointer items-start gap-3 rounded-xl border border-white/10 bg-white/[0.03] p-4"><input type="checkbox" checked={profile.isPublic} onChange={(event) => update('isPublic', event.target.checked)} className="mt-0.5 h-4 w-4 accent-orange-500" /><span><span className="block text-sm font-semibold text-white">Perfil público</span><span className="mt-1 block text-xs leading-relaxed text-gray-500">Permite que alunos vejam sua apresentação e seus cursos publicados.</span></span></label></section>}
        </div>
        <div className="flex justify-end border-t border-white/10 bg-black/20 p-5 sm:px-8"><button disabled={isSaving} className="inline-flex min-w-40 items-center justify-center gap-2 rounded-xl bg-orange-500 px-5 py-3 text-sm font-bold text-white shadow-lg shadow-orange-500/20 transition hover:bg-orange-600 disabled:opacity-60">{isSaving ? <Loader2 className="h-4 w-4 animate-spin" /> : <Save className="h-4 w-4" />} Salvar perfil</button></div>
      </form>
    </main>
  );
};

const UrlField: React.FC<{ icon: React.ReactNode; label: string; value: string | null; placeholder: string; onChange: (value: string) => void }> = ({ icon, label, value, placeholder, onChange }) => <label className="block"><span className="mb-2 flex items-center gap-2 text-xs font-semibold uppercase tracking-wider text-gray-400"><span className="text-orange-400 [&>svg]:h-4 [&>svg]:w-4">{icon}</span>{label}</span><input type="url" value={value || ''} onChange={(event) => onChange(event.target.value)} placeholder={placeholder} className={inputClass} /></label>;