import 'package:flutter/widgets.dart' show AssetImage;
import 'package:pdf/pdf.dart';
import 'package:pdf/widgets.dart' as pw;
import 'package:printing/printing.dart';
import '../../models/document_model.dart';

class PdfService {
  static Future<void> generateAndPrintReceipt(DocumentModel document) async {
    final pdf = pw.Document();
    
    // Load PFM logo asset
    final logoImage = await flutterImageProvider(const AssetImage('assets/logo.png'));
    final isProductScan = document.docType == 'Product';
    
    // Add page
    pdf.addPage(
      pw.Page(
        pageFormat: PdfPageFormat.a4,
        build: (pw.Context context) {
          return pw.Column(
            crossAxisAlignment: pw.CrossAxisAlignment.start,
            children: [
              // Header & Title
              pw.Row(
                mainAxisAlignment: pw.MainAxisAlignment.spaceBetween,
                children: [
                  pw.Text(
                    isProductScan ? 'BUKTI VERIFIKASI SCAN PRODUK' : 'TANDA TERIMA PENGIRIMAN', 
                    style: pw.TextStyle(fontSize: 22, fontWeight: pw.FontWeight.bold)
                  ),
                  pw.SizedBox(
                    width: 60,
                    height: 60,
                    child: pw.Image(logoImage),
                  ),
                ]
              ),
              pw.SizedBox(height: 20),
              
              // Document Headers
              pw.Container(
                padding: const pw.EdgeInsets.all(10),
                decoration: pw.BoxDecoration(
                  border: pw.Border.all(color: PdfColors.grey),
                  borderRadius: const pw.BorderRadius.all(pw.Radius.circular(8)),
                ),
                child: pw.Column(
                  crossAxisAlignment: pw.CrossAxisAlignment.start,
                  children: isProductScan 
                    ? [
                        _buildTextRow('Tanggal Scan', document.tanggal),
                        _buildTextRow('Toko / Cabang', document.kepadaYth),
                        _buildTextRow('Jenis Verifikasi', 'Pemindaian Produk & Kadaluwarsa'),
                      ]
                    : [
                        _buildTextRow('Tanggal', document.tanggal),
                        _buildTextRow('No PO', document.noPo),
                        _buildTextRow('No SO', document.noSo),
                        _buildTextRow('No DO', document.noDo),
                      ]
                ),
              ),
              pw.SizedBox(height: 20),
              
              // Detail Scan / Pengiriman Section
              pw.Text(
                isProductScan ? 'Informasi Verifikasi' : 'Detail Pengiriman', 
                style: pw.TextStyle(fontSize: 16, fontWeight: pw.FontWeight.bold)
              ),
              pw.SizedBox(height: 8),
              pw.Container(
                padding: const pw.EdgeInsets.all(10),
                decoration: pw.BoxDecoration(
                  color: PdfColors.grey100,
                  borderRadius: const pw.BorderRadius.all(pw.Radius.circular(8)),
                ),
                child: pw.Column(
                  crossAxisAlignment: pw.CrossAxisAlignment.start,
                  children: isProductScan
                    ? [
                        _buildTextRow('Nama Produk', document.items.isNotEmpty ? document.items.first.namaBarang : '-'),
                        _buildTextRow('Kode SKU', document.items.isNotEmpty ? document.items.first.nomorSku : '-'),
                        _buildTextRow('Nomor Batch', document.noDo),
                        _buildTextRow('Tanggal Expired', document.alamat.replaceAll("Product Scan: Expired ", "")),
                      ]
                    : [
                        _buildTextRow('Kepada Yth', document.kepadaYth),
                        _buildTextRow('Order Untuk', document.orderUntuk),
                        _buildTextRow('Alamat', document.alamat),
                        _buildTextRow('Plat Truk', document.platTruk),
                        _buildTextRow('Nama Driver', document.namaDriver),
                      ]
                ),
              ),
              pw.SizedBox(height: 20),

              // Items Table / Scanned Product Details
              pw.Text(
                isProductScan ? 'Detail Item Scanned' : 'Barang Dikirim', 
                style: pw.TextStyle(fontSize: 16, fontWeight: pw.FontWeight.bold)
              ),
              pw.SizedBox(height: 8),
              
              isProductScan
                ? pw.Table.fromTextArray(
                    context: context,
                    border: pw.TableBorder.all(color: PdfColors.grey),
                    headerDecoration: const pw.BoxDecoration(color: PdfColors.grey300),
                    headerHeight: 25,
                    cellHeight: 25,
                    columnWidths: {
                      0: const pw.FixedColumnWidth(100),   // SKU
                      1: const pw.FlexColumnWidth(2),     // Nama Barang
                      2: const pw.FixedColumnWidth(100),   // Batch
                      3: const pw.FixedColumnWidth(100),   // Expired
                    },
                    cellAlignments: {
                      0: pw.Alignment.centerLeft,
                      1: pw.Alignment.centerLeft,
                      2: pw.Alignment.center,
                      3: pw.Alignment.center,
                    },
                    headers: ['Nomor SKU', 'Nama Barang', 'Nomor Batch', 'Expired Date'],
                    data: [
                      [
                        document.items.isNotEmpty ? document.items.first.nomorSku : '-',
                        document.items.isNotEmpty ? document.items.first.namaBarang : '-',
                        document.noDo,
                        document.alamat.replaceAll("Product Scan: Expired ", ""),
                      ]
                    ],
                  )
                : pw.Table.fromTextArray(
                    context: context,
                    border: pw.TableBorder.all(color: PdfColors.grey),
                    headerDecoration: const pw.BoxDecoration(color: PdfColors.grey300),
                    headerHeight: 25,
                    cellHeight: 25,
                    columnWidths: {
                      0: const pw.FixedColumnWidth(80),   // SKU
                      1: const pw.FlexColumnWidth(2),     // Nama Barang
                      2: const pw.FixedColumnWidth(70),   // Banyak
                      3: const pw.FixedColumnWidth(70),   // Jumlah
                    },
                    cellAlignments: {
                      0: pw.Alignment.centerLeft,
                      1: pw.Alignment.centerLeft,
                      2: pw.Alignment.centerRight,
                      3: pw.Alignment.centerRight,
                    },
                    headers: ['Nomor SKU', 'Nama Barang', 'Banyak', 'Jumlah'],
                    data: document.items.map((item) {
                      return [
                        item.nomorSku,
                        item.namaBarang,
                        item.banyak,
                        item.jumlah,
                      ];
                    }).toList(),
                  ),
              
              pw.Spacer(),
              
              // Footer & Signatures
              pw.Row(
                mainAxisAlignment: pw.MainAxisAlignment.spaceBetween,
                children: isProductScan
                  ? [
                      pw.Column(
                        children: [
                          pw.SizedBox(height: 40),
                          pw.Text('_______________________', style: pw.TextStyle(fontWeight: pw.FontWeight.bold)),
                          pw.SizedBox(height: 4),
                          pw.Text('Petugas / Staff Toko'),
                        ]
                      ),
                      pw.Column(
                        children: [
                          pw.SizedBox(height: 40),
                          pw.Text('_______________________', style: pw.TextStyle(fontWeight: pw.FontWeight.bold)),
                          pw.SizedBox(height: 4),
                          pw.Text('Penanggung Jawab Toko'),
                        ]
                      )
                    ]
                  : [
                      pw.Column(
                        children: [
                          pw.SizedBox(height: 40),
                          pw.Text(document.namaDriver.isNotEmpty ? document.namaDriver : '_______________________', style: pw.TextStyle(fontWeight: pw.FontWeight.bold)),
                          pw.SizedBox(height: 4),
                          pw.Text('Pengirim (Driver)'),
                        ]
                      ),
                      pw.Column(
                        children: [
                          pw.SizedBox(height: 40),
                          pw.Text(document.namaPenerima.isNotEmpty ? document.namaPenerima : '_______________________', style: pw.TextStyle(fontWeight: pw.FontWeight.bold)),
                          pw.SizedBox(height: 4),
                          pw.Text('Penerima (Penjaga Toko)'),
                        ]
                      )
                    ]
              )
            ],
          );
        },
      ),
    );

    // Prompt user to view/print/save the PDF natively
    await Printing.layoutPdf(
      onLayout: (PdfPageFormat format) async => pdf.save(),
      format: PdfPageFormat.a4,
      name: isProductScan 
          ? 'ProductScan_${document.items.isNotEmpty ? document.items.first.nomorSku : "unknown"}' 
          : 'Document_${document.noDo.replaceAll('/', '_')}',
    );
  }

  static pw.Widget _buildTextRow(String label, String value) {
    return pw.Padding(
      padding: const pw.EdgeInsets.symmetric(vertical: 2),
      child: pw.Row(
        crossAxisAlignment: pw.CrossAxisAlignment.start,
        children: [
          pw.SizedBox(width: 100, child: pw.Text(label, style: pw.TextStyle(fontWeight: pw.FontWeight.bold))),
          pw.Expanded(
            child: pw.Text(': $value', softWrap: true),
          ),
        ]
      )
    );
  }
}