import { useEffect, useState } from 'react';
import { useTranslation } from 'react-i18next';
import { useNavigate } from 'react-router-dom';
import { BookOpen, Plus, Edit2, Trash2, ChevronRight, Building2, Sparkles, Loader2, X } from 'lucide-react';
import { useAuth } from '../lib/auth';
import { useTenant } from '../lib/tenant';
import { api } from '../lib/api';
import { useToast } from '../hooks/useToast';
import { logError } from '../lib/logger';

export default function TrackListPage() {
    const { t } = useTranslation();
    const toast = useToast();
    const { token } = useAuth();
    const { selectedOrgId } = useTenant();
    const navigate = useNavigate();
    const [tracks, setTracks] = useState<any[]>([]);
    const [loading, setLoading] = useState(true);

    // AI curriculum generator state
    const [aiModalOpen, setAiModalOpen] = useState(false);
    const [generating, setGenerating] = useState(false);
    const [aiForm, setAiForm] = useState({ description: '', numDays: 5, language: 'FR', targetAudience: '' });

    const load = async () => {
        if (!token || !selectedOrgId) return;
        try {
            const data = await api.get('/v1/admin/tracks', token, selectedOrgId);
            setTracks(data);
        } catch (err) {
            logError(err);
        } finally {
            setLoading(false);
        }
    };

    useEffect(() => {
        if (selectedOrgId && token) load();
    }, [selectedOrgId, token]);

    const del = async (id: string) => {
        if (!confirm(t('tracks.confirm_delete'))) return;
        try {
            await api.delete(`/v1/admin/tracks/${id}`, token, selectedOrgId);
            load();
        } catch (err) {
            logError(err);
        }
    };

    const handleAiGenerate = async (e: React.FormEvent) => {
        e.preventDefault();
        if (!token || !selectedOrgId || !aiForm.description.trim()) return;
        setGenerating(true);
        try {
            const res = await api.post(
                `/v1/organizations/${selectedOrgId}/content/ai-generate`,
                { ...aiForm, numDays: Number(aiForm.numDays) },
                token,
                selectedOrgId
            );
            setAiModalOpen(false);
            toast.success(`${res.track.title} — ${res.track.days.length} ${t('tracks.days')}`);
            load();
            navigate(`/content/${res.track.id}/days`);
        } catch (err: any) {
            toast.error(err?.message ?? t('tracks.ai_error'));
        } finally {
            setGenerating(false);
        }
    };

    if (!selectedOrgId) {
        return (
            <div className="flex flex-col items-center justify-center min-h-[60vh] text-slate-400">
                <Building2 className="w-12 h-12 mb-4 opacity-20" />
                <p className="max-w-xs text-center mt-2">{t('common.select_org')}</p>
            </div>
        );
    }

    if (loading) {
        return (
            <div className="flex flex-col items-center justify-center min-h-[60vh] text-slate-400">
                <div className="w-8 h-8 border-4 border-slate-200 border-t-slate-900 rounded-full animate-spin mb-4"></div>
                <p>{t('common.loading')}</p>
            </div>
        );
    }

    return (
        <div className="p-8">
            <div className="flex justify-between items-center mb-6">
                <h1 className="text-3xl font-bold text-slate-800">{t('tracks.title')}</h1>
                <div className="flex items-center gap-3">
                    <button
                        onClick={() => setAiModalOpen(true)}
                        className="flex items-center gap-2 bg-indigo-600 text-white px-4 py-2 rounded-xl text-sm font-bold hover:bg-indigo-700 shadow-lg shadow-indigo-100"
                    >
                        <Sparkles className="w-4 h-4" /> {t('tracks.ai_generate_btn')}
                    </button>
                    <button onClick={() => navigate('/content/new')} className="flex items-center gap-2 bg-slate-900 text-white px-4 py-2 rounded-xl text-sm font-bold hover:bg-slate-700">
                        <Plus className="w-4 h-4" /> {t('tracks.new')}
                    </button>
                </div>
            </div>

            <div className="grid gap-4">
                {tracks.map((track: any) => (
                    <div key={track.id} className="bg-white rounded-xl border border-slate-100 p-5 flex items-center justify-between shadow-sm hover:shadow-md transition">
                        <div className="flex items-center gap-4">
                            <div className="bg-purple-100 p-3 rounded-xl"><BookOpen className="w-5 h-5 text-purple-600" /></div>
                            <div>
                                <div className="flex items-center gap-2">
                                    <h3 className="font-bold text-slate-800">{track.title}</h3>
                                    {track.isPremium && <span className="bg-amber-100 text-amber-700 text-xs px-2 py-0.5 rounded-full font-medium">Premium</span>}
                                    <span className="bg-slate-100 text-slate-600 text-xs px-2 py-0.5 rounded-full">{track.language}</span>
                                </div>
                                <p className="text-sm text-slate-500 mt-0.5">{track._count?.days || 0} {t('tracks.days')} · {track._count?.enrollments || 0} {t('tracks.enrolled')} · {track.duration}j</p>
                            </div>
                        </div>
                        <div className="flex items-center gap-2">
                            <button onClick={() => navigate(`/content/${track.id}`)} className="p-2 text-slate-400 hover:text-blue-600 hover:bg-blue-50 rounded-lg"><Edit2 className="w-4 h-4" /></button>
                            <button onClick={() => navigate(`/content/${track.id}/days`)} className="flex items-center gap-1 text-sm text-slate-600 hover:text-slate-900 px-3 py-2 rounded-lg hover:bg-slate-50">{t('tracks.days_label')} <ChevronRight className="w-4 h-4" /></button>
                            <button onClick={() => del(track.id)} className="p-2 text-slate-400 hover:text-red-500 hover:bg-red-50 rounded-lg"><Trash2 className="w-4 h-4" /></button>
                        </div>
                    </div>
                ))}
                {!tracks.length && (
                    <div className="text-center py-16 text-slate-400">
                        <BookOpen className="w-12 h-12 mx-auto mb-3 opacity-30" />
                        <p>{t('tracks.no_tracks')}</p>
                        <button
                            onClick={() => setAiModalOpen(true)}
                            className="mt-4 inline-flex items-center gap-2 text-indigo-600 hover:text-indigo-700 font-semibold text-sm"
                        >
                            <Sparkles className="w-4 h-4" /> {t('tracks.ai_generate_first')}
                        </button>
                    </div>
                )}
            </div>

            {/* AI Curriculum Generator Modal */}
            {aiModalOpen && (
                <div className="fixed inset-0 z-50 flex items-center justify-center p-4">
                    <div className="absolute inset-0 bg-slate-900/40 backdrop-blur-sm" onClick={() => !generating && setAiModalOpen(false)} />
                    <div className="bg-white rounded-3xl w-full max-w-lg shadow-2xl relative z-10 overflow-hidden">
                        <div className="bg-gradient-to-br from-indigo-600 to-purple-600 px-8 pt-8 pb-6">
                            <div className="flex justify-between items-start">
                                <div>
                                    <div className="flex items-center gap-2 text-white/80 text-sm font-medium mb-1">
                                        <Sparkles className="w-4 h-4" /> {t('tracks.ai_modal_badge')}
                                    </div>
                                    <h2 className="text-2xl font-bold text-white">{t('tracks.ai_modal_title')}</h2>
                                    <p className="text-indigo-200 text-sm mt-1">{t('tracks.ai_modal_subtitle')}</p>
                                </div>
                                {!generating && (
                                    <button onClick={() => setAiModalOpen(false)} className="text-white/60 hover:text-white">
                                        <X className="w-5 h-5" />
                                    </button>
                                )}
                            </div>
                        </div>

                        <form onSubmit={handleAiGenerate} className="px-8 py-6 space-y-5">
                            <div>
                                <label className="block text-sm font-bold text-slate-700 mb-2">{t('tracks.ai_description_label')} *</label>
                                <textarea
                                    required
                                    rows={3}
                                    value={aiForm.description}
                                    onChange={e => setAiForm(f => ({ ...f, description: e.target.value }))}
                                    disabled={generating}
                                    placeholder={t('tracks.ai_description_placeholder')}
                                    className="w-full px-4 py-3 bg-slate-50 border border-slate-200 rounded-2xl outline-none focus:ring-2 focus:ring-indigo-500/20 focus:border-indigo-500 transition-all text-sm resize-none"
                                />
                            </div>

                            <div className="grid grid-cols-2 gap-4">
                                <div>
                                    <label className="block text-sm font-bold text-slate-700 mb-2">{t('tracks.ai_num_days')}</label>
                                    <input
                                        type="number"
                                        min={1}
                                        max={30}
                                        value={aiForm.numDays}
                                        onChange={e => setAiForm(f => ({ ...f, numDays: parseInt(e.target.value) || 5 }))}
                                        disabled={generating}
                                        className="w-full px-4 py-3 bg-slate-50 border border-slate-200 rounded-2xl outline-none focus:ring-2 focus:ring-indigo-500/20 focus:border-indigo-500 transition-all text-sm"
                                    />
                                </div>
                                <div>
                                    <label className="block text-sm font-bold text-slate-700 mb-2">{t('tracks.ai_language')}</label>
                                    <select
                                        value={aiForm.language}
                                        onChange={e => setAiForm(f => ({ ...f, language: e.target.value }))}
                                        disabled={generating}
                                        className="w-full px-4 py-3 bg-slate-50 border border-slate-200 rounded-2xl outline-none focus:ring-2 focus:ring-indigo-500/20 focus:border-indigo-500 transition-all text-sm"
                                    >
                                        <option value="FR">{t('tracks.ai_lang_fr')}</option>
                                        <option value="EN">{t('tracks.ai_lang_en')}</option>
                                        <option value="WOL">{t('tracks.ai_lang_wol')}</option>
                                    </select>
                                </div>
                            </div>

                            <div>
                                <label className="block text-sm font-bold text-slate-700 mb-2">{t('tracks.ai_audience')} <span className="text-slate-400 font-normal">({t('tracks.ai_audience_optional')})</span></label>
                                <input
                                    type="text"
                                    value={aiForm.targetAudience}
                                    onChange={e => setAiForm(f => ({ ...f, targetAudience: e.target.value }))}
                                    disabled={generating}
                                    placeholder={t('tracks.ai_audience_placeholder')}
                                    className="w-full px-4 py-3 bg-slate-50 border border-slate-200 rounded-2xl outline-none focus:ring-2 focus:ring-indigo-500/20 focus:border-indigo-500 transition-all text-sm"
                                />
                            </div>

                            <button
                                type="submit"
                                disabled={generating || !aiForm.description.trim()}
                                className="w-full py-4 bg-indigo-600 text-white rounded-2xl font-bold hover:bg-indigo-700 disabled:opacity-50 transition-all shadow-lg shadow-indigo-100 flex items-center justify-center gap-2"
                            >
                                {generating ? (
                                    <>
                                        <Loader2 className="w-4 h-4 animate-spin" />
                                        {t('tracks.ai_generating')}
                                    </>
                                ) : (
                                    <>
                                        <Sparkles className="w-4 h-4" />
                                        {t('tracks.ai_generate_submit')}
                                    </>
                                )}
                            </button>
                        </form>
                    </div>
                </div>
            )}
        </div>
    );
}