import 'package:flutter/services.dart';
import 'package:intl/intl.dart';
import 'package:pdf/pdf.dart';
import 'package:pdf/widgets.dart' as pw;

// ─── DTOs ─────────────────────────────────────────────────────────────────────

class WorkLogEntryDto {
  const WorkLogEntryDto({
    required this.type,
    required this.title,
    this.subtitle,
    required this.start,
    this.end,
    required this.isCreatorEvent,
    required this.duration,
  });

  // 'attendance' | 'task' | 'ticket' | 'isr' | 'passSlip' | 'vacant'
  final String type;
  final String title;
  final String? subtitle;
  final DateTime start;
  final DateTime? end;
  final bool isCreatorEvent;
  final Duration duration;
}

class WorkLogSummaryDto {
  const WorkLogSummaryDto({
    required this.totalAttendance,
    required this.totalTasks,
    required this.totalTickets,
    required this.totalIsrs,
    required this.totalPassSlip,
    required this.totalVacant,
  });

  final Duration totalAttendance;
  final Duration totalTasks;
  final Duration totalTickets;
  final Duration totalIsrs;
  final Duration totalPassSlip;
  final Duration totalVacant;

  Duration get totalActive =>
      totalAttendance + totalTasks + totalTickets + totalIsrs + totalPassSlip;
}

class DailyWorkLogDto {
  const DailyWorkLogDto({
    required this.date,
    required this.entries,
    required this.summary,
  });

  final DateTime date;
  final List<WorkLogEntryDto> entries;
  final WorkLogSummaryDto summary;

  bool get hasData => entries.any((e) => !e.isCreatorEvent);
}

// ─── Helpers ──────────────────────────────────────────────────────────────────

String _fmt(Duration d) {
  if (d.inMinutes < 1) return '< 1m';
  final h = d.inHours;
  final m = d.inMinutes % 60;
  return h > 0 ? '${h}h ${m}m' : '${m}m';
}

String _fmtTime(DateTime dt) => DateFormat('h:mm a').format(dt);

Future<pw.Font> _font(String path) async {
  final data = await rootBundle.load(path);
  return pw.Font.ttf(data);
}

String _typeLabel(String type) => switch (type) {
      'attendance' => 'Attendance',
      'task' => 'Task',
      'ticket' => 'Ticket',
      'isr' => 'ISR',
      'passSlip' => 'Pass Slip',
      'vacant' => 'Vacant',
      _ => type,
    };

pw.TableRow _headerRow(pw.Font bold, List<String> labels) => pw.TableRow(
      decoration: const pw.BoxDecoration(color: PdfColors.grey200),
      children: labels
          .map((l) => pw.Padding(
                padding: const pw.EdgeInsets.all(4),
                child: pw.Text(l, style: pw.TextStyle(font: bold, fontSize: 8)),
              ))
          .toList(),
    );

pw.Widget _cell(String text, {bool bold = false, pw.Font? boldFont}) =>
    pw.Padding(
      padding: const pw.EdgeInsets.all(4),
      child: pw.Text(
        text,
        style: bold && boldFont != null
            ? pw.TextStyle(font: boldFont, fontSize: 8)
            : const pw.TextStyle(fontSize: 8),
      ),
    );

pw.TableRow _summaryRow(
  String label,
  Duration dur, {
  bool isBold = false,
  pw.Font? boldFont,
}) =>
    pw.TableRow(children: [
      pw.Padding(
        padding: const pw.EdgeInsets.all(4),
        child: pw.Text(
          label,
          style: isBold && boldFont != null
              ? pw.TextStyle(font: boldFont, fontSize: 9)
              : const pw.TextStyle(fontSize: 9),
        ),
      ),
      pw.Padding(
        padding: const pw.EdgeInsets.all(4),
        child: pw.Text(
          _fmt(dur),
          style: isBold && boldFont != null
              ? pw.TextStyle(font: boldFont, fontSize: 9)
              : const pw.TextStyle(fontSize: 9),
        ),
      ),
    ]);

// ─── Daily PDF ────────────────────────────────────────────────────────────────

Future<Uint8List> buildDailyWorkLogPdfBytes({
  required String personName,
  required DateTime date,
  required List<WorkLogEntryDto> entries,
  required WorkLogSummaryDto summary,
}) async {
  final regular = await _font('assets/fonts/Roboto-Regular.ttf');
  final bold = await _font('assets/fonts/Roboto-Bold.ttf');
  final dateFmt = DateFormat('EEEE, MMMM d, yyyy');

  final doc = pw.Document();
  doc.addPage(pw.MultiPage(
    pageFormat: PdfPageFormat.a4,
    margin: const pw.EdgeInsets.all(32),
    theme: pw.ThemeData.withFont(base: regular, bold: bold),
    header: (ctx) => pw.Column(
      crossAxisAlignment: pw.CrossAxisAlignment.start,
      children: [
        pw.Text('Work Log',
            style: pw.TextStyle(font: bold, fontSize: 18)),
        pw.SizedBox(height: 2),
        pw.Text(personName, style: const pw.TextStyle(fontSize: 12)),
        pw.Text(dateFmt.format(date),
            style:
                const pw.TextStyle(fontSize: 11, color: PdfColors.grey700)),
        pw.Divider(thickness: 0.5),
      ],
    ),
    footer: (ctx) => pw.Align(
      alignment: pw.Alignment.centerRight,
      child: pw.Text(
        'Page ${ctx.pageNumber} of ${ctx.pagesCount}  •  Generated by Tasq',
        style:
            const pw.TextStyle(fontSize: 8, color: PdfColors.grey600),
      ),
    ),
    build: (ctx) => [
      pw.Table(
        border: pw.TableBorder.all(width: 0.4, color: PdfColors.grey400),
        columnWidths: const {
          0: pw.FixedColumnWidth(68),
          1: pw.FixedColumnWidth(68),
          2: pw.FixedColumnWidth(58),
          3: pw.FlexColumnWidth(),
          4: pw.FixedColumnWidth(44),
        },
        children: [
          _headerRow(bold, ['Start', 'End', 'Type', 'Description', 'Duration']),
          for (final e in entries.where((e) => !e.isCreatorEvent))
            pw.TableRow(children: [
              _cell(_fmtTime(e.start)),
              _cell(e.end != null ? _fmtTime(e.end!) : '—'),
              _cell(_typeLabel(e.type)),
              pw.Padding(
                padding: const pw.EdgeInsets.all(4),
                child: pw.Column(
                  crossAxisAlignment: pw.CrossAxisAlignment.start,
                  children: [
                    pw.Text(e.title,
                        style: const pw.TextStyle(fontSize: 8)),
                    if (e.subtitle != null)
                      pw.Text(e.subtitle!,
                          style: const pw.TextStyle(
                              fontSize: 7, color: PdfColors.grey700)),
                  ],
                ),
              ),
              _cell(_fmt(e.duration)),
            ]),
        ],
      ),
      pw.SizedBox(height: 12),
      pw.Text('Summary',
          style: pw.TextStyle(font: bold, fontSize: 11)),
      pw.SizedBox(height: 4),
      pw.Table(
        border: pw.TableBorder.all(width: 0.4, color: PdfColors.grey400),
        columnWidths: const {
          0: pw.FlexColumnWidth(),
          1: pw.FixedColumnWidth(60),
        },
        children: [
          if (summary.totalAttendance > Duration.zero)
            _summaryRow('Attendance', summary.totalAttendance, boldFont: bold),
          if (summary.totalTasks > Duration.zero)
            _summaryRow('Tasks', summary.totalTasks, boldFont: bold),
          if (summary.totalTickets > Duration.zero)
            _summaryRow('Tickets', summary.totalTickets, boldFont: bold),
          if (summary.totalIsrs > Duration.zero)
            _summaryRow('IT Service Requests', summary.totalIsrs, boldFont: bold),
          if (summary.totalPassSlip > Duration.zero)
            _summaryRow('Pass Slips', summary.totalPassSlip, boldFont: bold),
          _summaryRow('Total Active', summary.totalActive,
              isBold: true, boldFont: bold),
        ],
      ),
    ],
  ));
  return doc.save();
}

// ─── Multi-day Summary PDF ────────────────────────────────────────────────────

Future<Uint8List> buildMultiDayWorkLogPdfBytes({
  required String personName,
  required DateTime rangeStart,
  required DateTime rangeEnd,
  required String modeLabel,
  required List<DailyWorkLogDto> days,
}) async {
  final regular = await _font('assets/fonts/Roboto-Regular.ttf');
  final bold = await _font('assets/fonts/Roboto-Bold.ttf');
  final dateFmt = DateFormat('MMM d, yyyy');
  final dayFmt = DateFormat('EEE, MMM d');

  final doc = pw.Document();
  doc.addPage(pw.MultiPage(
    pageFormat: PdfPageFormat.a4,
    margin: const pw.EdgeInsets.all(32),
    theme: pw.ThemeData.withFont(base: regular, bold: bold),
    header: (ctx) => pw.Column(
      crossAxisAlignment: pw.CrossAxisAlignment.start,
      children: [
        pw.Text('Work Log — $modeLabel',
            style: pw.TextStyle(font: bold, fontSize: 18)),
        pw.SizedBox(height: 2),
        pw.Text(personName, style: const pw.TextStyle(fontSize: 12)),
        pw.Text(
          '${dateFmt.format(rangeStart)} – '
          '${dateFmt.format(rangeEnd.subtract(const Duration(days: 1)))}',
          style:
              const pw.TextStyle(fontSize: 11, color: PdfColors.grey700),
        ),
        pw.Divider(thickness: 0.5),
      ],
    ),
    footer: (ctx) => pw.Align(
      alignment: pw.Alignment.centerRight,
      child: pw.Text(
        'Page ${ctx.pageNumber} of ${ctx.pagesCount}  •  Generated by Tasq',
        style:
            const pw.TextStyle(fontSize: 8, color: PdfColors.grey600),
      ),
    ),
    build: (ctx) => [
      pw.Table(
        border: pw.TableBorder.all(width: 0.4, color: PdfColors.grey400),
        columnWidths: const {
          0: pw.FixedColumnWidth(80),
          1: pw.FixedColumnWidth(54),
          2: pw.FixedColumnWidth(40),
          3: pw.FixedColumnWidth(40),
          4: pw.FixedColumnWidth(36),
          5: pw.FixedColumnWidth(46),
          6: pw.FixedColumnWidth(38),
          7: pw.FixedColumnWidth(48),
        },
        children: [
          _headerRow(bold,
              ['Date', 'Attend.', 'Tasks', 'Tickets', 'ISR', 'Pass Slip', 'Idle', 'Total']),
          for (final day in days)
            pw.TableRow(
              decoration: day.hasData
                  ? null
                  : const pw.BoxDecoration(color: PdfColors.grey100),
              children: [
                _cell(dayFmt.format(day.date)),
                _cell(day.hasData ? _fmt(day.summary.totalAttendance) : '—'),
                _cell(day.hasData ? _fmt(day.summary.totalTasks) : '—'),
                _cell(day.hasData ? _fmt(day.summary.totalTickets) : '—'),
                _cell(day.hasData ? _fmt(day.summary.totalIsrs) : '—'),
                _cell(day.hasData ? _fmt(day.summary.totalPassSlip) : '—'),
                _cell(day.hasData ? _fmt(day.summary.totalVacant) : '—'),
                _cell(day.hasData ? _fmt(day.summary.totalActive) : '—'),
              ],
            ),
        ],
      ),
    ],
  ));
  return doc.save();
}