/**
 * ════════════════════════════════════════════════════════════
 * مُصادَق (Musadaq) — Invoices Management Page
 * ════════════════════════════════════════════════════════════
 */

import { useState, useEffect } from 'react';
import { motion, AnimatePresence } from 'framer-motion';
import { 
    Upload, 
    Search, 
    Filter, 
    Eye, 
    CheckCircle2, 
    Clock, 
    AlertCircle, 
    MoreVertical,
    ChevronLeft,
    ChevronRight,
    Building2,
    FileText,
    Send
} from 'lucide-react';
import apiClient from '../../api/client';

export const InvoicesPage = () => {
    const [invoices, setInvoices] = useState<any[]>([]);
    const [companies, setCompanies] = useState<any[]>([]);
    const [isLoading, setIsLoading] = useState(true);
    const [searchTerm, setSearchTerm] = useState('');
    const [isUploadModalOpen, setIsUploadModalOpen] = useState(false);
    
    // Upload Form State
    const [selectedCompanyId, setSelectedCompanyId] = useState('');
    const [selectedFile, setSelectedFile] = useState<File | null>(null);
    const [isUploading, setIsUploading] = useState(false);

    const fetchData = async () => {
        setIsLoading(true);
        try {
            // Fetch companies first so the dropdown always works
            try {
                const compRes = await apiClient.get('/companies');
                console.log('Fetched Companies:', compRes.data);
                setCompanies(compRes.data);
            } catch (err) {
                console.error('Failed to fetch companies', err);
            }

            // Fetch invoices separately
            try {
                const invRes = await apiClient.get('/invoices');
                console.log('Fetched Invoices:', invRes.data);
                setInvoices(invRes.data);
            } catch (err) {
                console.error('Failed to fetch invoices', err);
            }
        } finally {
            setIsLoading(false);
        }
    };

    useEffect(() => {
        fetchData();
    }, []);

    const handleUpload = async (e: React.FormEvent) => {
        e.preventDefault();
        if (!selectedCompanyId || !selectedFile) return;

        setIsUploading(true);
        const formData = new FormData();
        formData.append('file', selectedFile);

        try {
            await apiClient.post(`/invoices/upload/${selectedCompanyId}`, formData, {
                headers: { 'Content-Type': 'multipart/form-data' }
            });
            setIsUploadModalOpen(false);
            setSelectedFile(null);
            setSelectedCompanyId('');
            fetchData();
        } catch (error) {
            console.error('Upload failed', error);
            alert('حدث خطأ أثناء رفع الفاتورة');
        } finally {
            setIsUploading(false);
        }
    };

    const handleFileChange = (e: React.ChangeEvent<HTMLInputElement>) => {
        if (e.target.files && e.target.files[0]) {
            setSelectedFile(e.target.files[0]);
        }
    };

    const filteredInvoices = invoices.filter(inv => 
        inv.invoice_number?.includes(searchTerm) || 
        inv.company?.name?.includes(searchTerm)
    );

    const StatusBadge = ({ status }: { status: string }) => {
        const config: any = {
            approved: { color: 'text-emerald-700 bg-emerald-50 border-emerald-100', icon: CheckCircle2, label: 'تم التصديق' },
            validated: { color: 'text-blue-700 bg-blue-50 border-blue-100', icon: CheckCircle2, label: 'جاهز للإرسال' },
            extracted: { color: 'text-indigo-700 bg-indigo-50 border-indigo-100', icon: CheckCircle2, label: 'تم الاستخراج' },
            uploaded: { color: 'text-amber-700 bg-amber-50 border-amber-100', icon: Clock, label: 'قيد المعالجة AI' },
            extracting: { color: 'text-amber-700 bg-amber-50 border-amber-100', icon: Clock, label: 'قيد الاستخراج' },
            validation_failed: { color: 'text-red-700 bg-red-50 border-red-100', icon: AlertCircle, label: 'خطأ في التحقق' },
        };
        const { color, icon: Icon, label } = config[status] || { color: 'text-slate-500 bg-slate-50', icon: Clock, label: status };
        return (
            <span className={`inline-flex items-center gap-1.5 px-3 py-1 rounded-full text-[10px] font-bold border ${color} uppercase tracking-tight`}>
                <Icon className="w-3 h-3" />
                {label}
            </span>
        );
    };

    return (
        <div className="space-y-8 h-full flex flex-col animate-in fade-in slide-in-from-bottom-4 duration-700">
            <header className="flex items-center justify-between">
                <div>
                    <h2 className="text-3xl font-bold text-slate-900">إدارة الفواتير</h2>
                    <p className="text-slate-500 mt-1">عرض، معالجة، وإرسال الفواتير الضريبية لبوابة الضريبة.</p>
                </div>
                <button 
                    onClick={() => setIsUploadModalOpen(true)}
                    className="btn-primary py-3 px-8 rounded-2xl flex items-center gap-2 shadow-xl shadow-primary-500/25 active:scale-95 transition-all"
                >
                    <Upload className="w-5 h-5" />
                    رفع فاتورة جديدة
                </button>
            </header>

            {/* ── Filter & Search Bar ──────────────────────────────── */}
            <div className="flex gap-4">
                <div className="flex-1 glass border-slate-200 rounded-2xl px-4 py-3 flex items-center gap-3">
                    <Search className="w-5 h-5 text-slate-400" />
                    <input 
                        type="text" 
                        placeholder="ابحث برقم الفاتورة، اسم الشركة، أو التاريخ..." 
                        className="bg-transparent border-none outline-none flex-1 text-slate-800 text-sm"
                        value={searchTerm}
                        onChange={(e) => setSearchTerm(e.target.value)}
                    />
                </div>
                <button className="glass border-slate-200 px-6 rounded-2xl flex items-center gap-2 text-slate-600 hover:bg-slate-50 transition-all font-semibold">
                    <Filter className="w-4 h-4" />
                    فلترة
                </button>
            </div>

            {/* ── Invoices Table ───────────────────────────────────── */}
            <div className="flex-1 card-premium overflow-hidden flex flex-col bg-white border border-slate-100">
                {isLoading ? (
                    <div className="flex-1 flex justify-center items-center">
                        <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-primary-600"></div>
                    </div>
                ) : filteredInvoices.length === 0 ? (
                    <div className="flex-1 flex flex-col items-center justify-center p-20 text-center">
                        <div className="w-24 h-24 bg-slate-50 rounded-full flex items-center justify-center mb-6 border border-slate-100">
                            <FileText className="w-10 h-10 text-slate-300" />
                        </div>
                        <h3 className="text-xl font-bold text-slate-900 mb-2">لا توجد فواتير بعد</h3>
                        <p className="text-slate-500 max-w-sm mb-8">ابدأ برفع أول فاتورة ليقوم محرك الذكاء الاصطناعي باستخراج بياناتها ومصادقتها ضريبياً.</p>
                        <button onClick={() => setIsUploadModalOpen(true)} className="btn-primary py-3 px-8 rounded-2xl flex items-center gap-2">
                             ارفع فاتورتك الأولى
                        </button>
                    </div>
                ) : (
                    <div className="overflow-x-auto">
                        <table className="w-full text-right border-collapse">
                            <thead className="bg-slate-50/80 border-b border-slate-100">
                                <tr>
                                    <th className="px-6 py-4 text-sm font-bold text-slate-500">رقم الفاتورة</th>
                                    <th className="px-6 py-4 text-sm font-bold text-slate-500">الشركة</th>
                                    <th className="px-6 py-4 text-sm font-bold text-slate-500">التاريخ</th>
                                    <th className="px-6 py-4 text-sm font-bold text-slate-500 text-left">المجموع (JOD)</th>
                                    <th className="px-6 py-4 text-sm font-bold text-slate-500">الحالة</th>
                                    <th className="px-6 py-4 text-sm font-bold text-slate-500 w-20 text-center">إجراءات</th>
                                </tr>
                            </thead>
                            <tbody className="divide-y divide-slate-100">
                                {filteredInvoices.map((inv, idx) => (
                                    <motion.tr 
                                        key={inv.id}
                                        initial={{ opacity: 0, x: 20 }}
                                        animate={{ opacity: 1, x: 0 }}
                                        transition={{ delay: idx * 0.05 }}
                                        className="hover:bg-slate-50/50 transition-colors group cursor-pointer"
                                    >
                                        <td className="px-6 py-4 font-bold text-slate-900">{inv.invoice_number || '---'}</td>
                                        <td className="px-6 py-4 text-slate-600 font-medium">
                                            <div className="flex items-center gap-2">
                                                <div className="w-7 h-7 bg-slate-100 rounded-md flex items-center justify-center">
                                                    <Building2 className="w-4 h-4 text-slate-400" />
                                                </div>
                                                {inv.company?.name || 'شركة غير معروفة'}
                                            </div>
                                        </td>
                                        <td className="px-6 py-4 text-slate-500 text-sm">
                                            {inv.issue_date ? new Date(inv.issue_date).toLocaleDateString('ar-JO') : '---'}
                                        </td>
                                        <td className="px-6 py-4 font-mono font-bold text-slate-800 text-left">
                                            {Number(inv.total_amount).toLocaleString('en-US', { minimumFractionDigits: 3 })}
                                        </td>
                                        <td className="px-6 py-4"><StatusBadge status={inv.status} /></td>
                                        <td className="px-6 py-4 text-center">
                                            <div className="flex items-center justify-center gap-1 opacity-0 group-hover:opacity-100 transition-opacity">
                                                <button className="p-2 text-slate-400 hover:text-primary-600 hover:bg-primary-50 rounded-lg transition-all">
                                                    <Eye className="w-4 h-4" />
                                                </button>
                                                {inv.status === 'validated' && (
                                                    <button className="p-2 text-emerald-500 hover:text-emerald-600 hover:bg-emerald-50 rounded-lg transition-all" title="إرسال لجو فوترة">
                                                        <Send className="w-4 h-4" />
                                                    </button>
                                                )}
                                                <button className="p-2 text-slate-400 hover:text-slate-600 hover:bg-slate-100 rounded-lg transition-all">
                                                    <MoreVertical className="w-4 h-4" />
                                                </button>
                                            </div>
                                        </td>
                                    </motion.tr>
                                ))}
                            </tbody>
                        </table>
                    </div>
                )}

                {/* ── Pagination ───────────────────────────────────────── */}
                {!isLoading && filteredInvoices.length > 0 && (
                    <footer className="px-6 py-4 bg-slate-50/50 border-t border-slate-100 flex items-center justify-between">
                        <p className="text-sm text-slate-500">عرض {filteredInvoices.length} فواتير</p>
                        <div className="flex gap-2">
                            <button className="p-2 text-slate-400 hover:text-slate-600 disabled:opacity-30 border border-slate-200 rounded-xl bg-white shadow-sm">
                                <ChevronRight className="w-5 h-5" />
                            </button>
                            <button className="p-2 text-slate-400 hover:text-slate-600 disabled:opacity-30 border border-slate-200 rounded-xl bg-white shadow-sm">
                                <ChevronLeft className="w-5 h-5" />
                            </button>
                        </div>
                    </footer>
                )}
            </div>

            {/* ── Upload Modal ─────────────────────────────────────── */}
            <AnimatePresence>
                {isUploadModalOpen && (
                    <div className="fixed inset-0 z-50 flex items-center justify-center p-4 bg-slate-900/60 backdrop-blur-sm">
                        <motion.div 
                            initial={{ scale: 0.9, opacity: 0 }}
                            animate={{ scale: 1, opacity: 1 }}
                            exit={{ scale: 0.9, opacity: 0 }}
                            className="bg-white rounded-[32px] p-8 w-full max-w-xl shadow-2xl overflow-hidden relative"
                        >
                            <div className="absolute top-0 right-0 w-32 h-32 bg-primary-50 rounded-full -mr-16 -mt-16 opacity-50" />
                            
                            <h3 className="text-2xl font-bold text-slate-900 mb-2 relative">رفع فاتورة جديدة</h3>
                            <p className="text-slate-500 mb-8 relative">اختر الشركة وملف الفاتورة (PDF أو صورة) وسيقوم الذكاء الاصطناعي بالباقي.</p>
                            
                            <form onSubmit={handleUpload} className="space-y-6 relative">
                                <div>
                                    <label className="block text-sm font-bold text-slate-700 mb-2">اختر الشركة</label>
                                    <select 
                                        required
                                        value={selectedCompanyId}
                                        onChange={e => setSelectedCompanyId(e.target.value)}
                                        className="w-full bg-slate-50 border border-slate-200 rounded-2xl px-5 py-4 outline-none focus:border-primary-500 focus:ring-4 focus:ring-primary-500/10 transition-all appearance-none cursor-pointer"
                                    >
                                        <option value="">-- اختر شركة --</option>
                                        {companies.map(c => (
                                            <option key={c.id} value={c.id}>{c.name}</option>
                                        ))}
                                    </select>
                                </div>

                                <div>
                                    <label className="block text-sm font-bold text-slate-700 mb-2">ملف الفاتورة</label>
                                    <div className="relative group">
                                        <input 
                                            type="file" 
                                            required
                                            onChange={handleFileChange}
                                            accept=".pdf,image/*"
                                            className="absolute inset-0 w-full h-full opacity-0 cursor-pointer z-10"
                                        />
                                        <div className="border-2 border-dashed border-slate-200 rounded-2xl p-10 flex flex-col items-center group-hover:border-primary-400 group-hover:bg-primary-50/30 transition-all bg-slate-50/50">
                                            <div className="w-14 h-14 bg-white rounded-2xl shadow-sm flex items-center justify-center mb-4 group-hover:scale-110 transition-transform">
                                                <Upload className="w-7 h-7 text-primary-600" />
                                            </div>
                                            <p className="font-bold text-slate-800">
                                                {selectedFile ? selectedFile.name : 'اسحب الملف هنا أو انقر للاختيار'}
                                            </p>
                                            <p className="text-sm text-slate-400 mt-1">PDF, JPG, PNG (حد أقصى 10MB)</p>
                                        </div>
                                    </div>
                                </div>

                                <div className="flex gap-4 pt-4">
                                    <button 
                                        type="button"
                                        onClick={() => setIsUploadModalOpen(false)}
                                        className="flex-1 bg-slate-100 text-slate-700 font-bold py-4 rounded-2xl hover:bg-slate-200 transition-all"
                                    >
                                        إلغاء
                                    </button>
                                    <button 
                                        type="submit"
                                        disabled={isUploading || !selectedCompanyId || !selectedFile}
                                        className="flex-[2] btn-primary py-4 rounded-2xl shadow-lg shadow-primary-500/30 disabled:opacity-50 flex items-center justify-center gap-3"
                                    >
                                        {isUploading ? (
                                            <>
                                                <div className="w-5 h-5 border-2 border-white/30 border-t-white rounded-full animate-spin" />
                                                جاري الرفع والمعالجة...
                                            </>
                                        ) : (
                                            <>
                                                <Upload className="w-5 h-5" />
                                                ابدأ المعالجة الآن
                                            </>
                                        )}
                                    </button>
                                </div>
                            </form>
                        </motion.div>
                    </div>
                )}
            </AnimatePresence>
        </div>
    );
};