import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import 'package:google_fonts/google_fonts.dart';
import 'package:intl/intl.dart';
import '../../../database/database.dart';
import '../../../providers/auth_provider.dart';
import '../../../providers/sync_provider.dart';

class SyncPage extends ConsumerStatefulWidget {
  const SyncPage({super.key});

  @override
  ConsumerState<SyncPage> createState() => _SyncPageState();
}

class _SyncPageState extends ConsumerState<SyncPage>
    with SingleTickerProviderStateMixin {
  bool _forceFullSync = false;
  late AnimationController _syncIconController;

  @override
  void initState() {
    super.initState();
    _syncIconController = AnimationController(
      vsync: this,
      duration: const Duration(seconds: 2),
    );
  }

  @override
  void dispose() {
    _syncIconController.dispose();
    super.dispose();
  }

  String _formatLastSyncTime(DateTime? time) {
    if (time == null) return 'Mai';
    final now = DateTime.now();
    final today = DateTime(now.year, now.month, now.day);
    final syncDate = DateTime(time.year, time.month, time.day);
    final timeStr = DateFormat('HH:mm').format(time);

    if (syncDate == today) {
      return 'Oggi, $timeStr';
    } else if (syncDate == today.subtract(const Duration(days: 1))) {
      return 'Ieri, $timeStr';
    } else {
      return DateFormat('dd/MM/yyyy, HH:mm').format(time);
    }
  }

  @override
  Widget build(BuildContext context) {
    final authState = ref.watch(authProvider);
    final syncState = ref.watch(syncProvider);
    final theme = Theme.of(context);
    final agente = authState.agente;
    final colorScheme = theme.colorScheme;

    ref.listen<SyncState>(syncProvider, (prev, next) {
      if (next.isSyncing && !(prev?.isSyncing ?? false)) {
        _syncIconController.repeat();
      } else if (!next.isSyncing && (prev?.isSyncing ?? false)) {
        _syncIconController.stop();
        _syncIconController.reset();
        if (next.error == null && next.progress >= 1.0) {
          ScaffoldMessenger.of(context).showSnackBar(
            const SnackBar(content: Text('Trasmissione terminata')),
          );
        }
      }
    });

    return Scaffold(
      appBar: AppBar(
        title: const Text('Sincronizzazione'),
        actions: [
          IconButton(
            icon: const Icon(Icons.settings),
            onPressed: () => context.push('/dashboard/sync/settings'),
          ),
        ],
      ),
      body: SingleChildScrollView(
        padding: const EdgeInsets.all(16),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            // Hero section: Toggle + Start button
            LayoutBuilder(
              builder: (context, constraints) {
                final isWide = constraints.maxWidth > 600;
                if (isWide) {
                  return Row(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Expanded(flex: 1, child: _buildToggleCard(context, syncState)),
                      const SizedBox(width: 16),
                      Expanded(
                        flex: 2,
                        child: _buildActionCard(
                          context,
                          agente,
                          syncState,
                          colorScheme,
                        ),
                      ),
                    ],
                  );
                }
                return Column(
                  children: [
                    _buildToggleCard(context, syncState),
                    const SizedBox(height: 16),
                    _buildActionCard(context, agente, syncState, colorScheme),
                  ],
                );
              },
            ),
            const SizedBox(height: 16),

            // Progress section
            if (syncState.phases.isNotEmpty || syncState.isSyncing || syncState.progress >= 1.0)
              _buildProgressSection(context, syncState, colorScheme),

            // Error section
            if (syncState.error != null) ...[
              const SizedBox(height: 16),
              _buildErrorCard(context, syncState, colorScheme),
            ],
          ],
        ),
      ),
    );
  }

  Widget _buildToggleCard(BuildContext context, SyncState syncState) {
    final theme = Theme.of(context);
    return Card(
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text(
              'Tipo Sincronizzazione',
              style: theme.textTheme.titleLarge,
            ),
            const SizedBox(height: 8),
            Text(
              'Scegli tra sincronizzazione parziale delle variazioni o scaricamento integrale di tutti i dati dal server.',
              style: theme.textTheme.bodyMedium?.copyWith(
                color: theme.colorScheme.onSurfaceVariant,
              ),
            ),
            const SizedBox(height: 16),
            Container(
              padding: const EdgeInsets.all(12),
              decoration: BoxDecoration(
                color: theme.colorScheme.surface,
                borderRadius: BorderRadius.circular(8),
                border: Border.all(
                  color: theme.colorScheme.outlineVariant.withValues(alpha: 0.3),
                ),
              ),
              child: Row(
                children: [
                  Switch(
                    value: _forceFullSync,
                    onChanged: syncState.isSyncing
                        ? null
                        : (v) => setState(() => _forceFullSync = v),
                  ),
                  const SizedBox(width: 12),
                  Expanded(
                    child: Text(
                      'Sincronizzazione completa',
                      style: theme.textTheme.labelLarge,
                    ),
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildActionCard(
    BuildContext context,
    Agente? agente,
    SyncState syncState,
    ColorScheme colorScheme,
  ) {
    final theme = Theme.of(context);
    return Card(
      child: Padding(
        padding: const EdgeInsets.all(24),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            FilledButton.icon(
              onPressed: syncState.isSyncing || agente == null
                  ? null
                  : () => ref.read(syncProvider.notifier).startFullSync(
                        agente.idAgente,
                        agente.codAgente!,
                        forceFullSync: _forceFullSync,
                      ),
              icon: syncState.isSyncing
                  ? RotationTransition(
                      turns: _syncIconController,
                      child: const Icon(Icons.sync),
                    )
                  : const Icon(Icons.sync),
              label: Text(
                syncState.isSyncing ? 'Sincronizzazione in corso...' : 'Avvia Sincronizzazione',
              ),
              style: FilledButton.styleFrom(
                padding: const EdgeInsets.symmetric(horizontal: 32, vertical: 20),
                textStyle: theme.textTheme.titleLarge,
              ),
            ),
            const SizedBox(height: 12),
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Icon(
                  Icons.schedule,
                  size: 16,
                  color: colorScheme.onSurfaceVariant,
                ),
                const SizedBox(width: 6),
                Text(
                  'Ultimo aggiornamento: ${_formatLastSyncTime(syncState.lastSyncTime)}',
                  style: theme.textTheme.bodyMedium?.copyWith(
                    color: colorScheme.onSurfaceVariant,
                  ),
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildProgressSection(
    BuildContext context,
    SyncState syncState,
    ColorScheme colorScheme,
  ) {
    final theme = Theme.of(context);
    final percent = syncState.phases.isNotEmpty
        ? (syncState.progress * 100).toInt()
        : 0;

    return Card(
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          // Header
          Container(
            padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
            decoration: BoxDecoration(
              color: theme.colorScheme.surface,
              border: Border(
                bottom: BorderSide(color: theme.colorScheme.outlineVariant),
              ),
            ),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      syncState.currentAgentCode != null
                          ? 'Sincronizzazione dati agente (${syncState.currentAgentCode})'
                          : 'Sincronizzazione dati agente',
                      style: theme.textTheme.titleLarge,
                    ),
                    if (syncState.agentiCodici.isNotEmpty)
                      RichText(
                        text: TextSpan(
                          style: theme.textTheme.bodyMedium?.copyWith(
                            color: colorScheme.onSurfaceVariant,
                          ),
                          children: [
                            const TextSpan(
                                text:
                                    'Stato complessivo del processo (Agenti: '),
                            for (int i = 0;
                                i < syncState.agentiCodici.length;
                                i++) ...[
                              if (i > 0) const TextSpan(text: ', '),
                              TextSpan(
                                text: syncState.agentiCodici[i],
                                style: syncState.agentiCodici[i] ==
                                        syncState.currentAgentCode
                                    ? TextStyle(
                                        fontWeight: FontWeight.bold,
                                        color: colorScheme.onSurfaceVariant,
                                      )
                                    : null,
                              ),
                            ],
                            const TextSpan(text: ')'),
                          ],
                        ),
                      )
                    else
                      Text(
                        'Stato complessivo del processo',
                        style: theme.textTheme.bodyMedium?.copyWith(
                          color: colorScheme.onSurfaceVariant,
                        ),
                      ),
                  ],
                ),
                Text(
                  '$percent%',
                  style: theme.textTheme.headlineMedium?.copyWith(
                    color: colorScheme.secondary,
                  ),
                ),
              ],
            ),
          ),

          // Progress bar + phases
          Padding(
            padding: const EdgeInsets.all(16),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.stretch,
              children: [
                // Main progress bar
                ClipRRect(
                  borderRadius: BorderRadius.circular(4),
                  child: LinearProgressIndicator(
                    value: syncState.progress,
                    minHeight: 8,
                    backgroundColor: theme.colorScheme.surfaceContainerHighest,
                    valueColor: AlwaysStoppedAnimation<Color>(
                      colorScheme.secondary,
                    ),
                  ),
                ),
                const SizedBox(height: 16),

                // Phases grid
                ...syncState.phases.asMap().entries.map(
                      (entry) => _buildPhaseRow(
                        context,
                        entry.key,
                        entry.value,
                        colorScheme,
                      ),
                    ),
              ],
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildPhaseRow(
    BuildContext context,
    int index,
    SyncPhaseInfo phase,
    ColorScheme colorScheme,
  ) {
    final theme = Theme.of(context);
    final isCompleted = phase.status == SyncPhaseStatus.completed;

    return Container(
      margin: const EdgeInsets.only(bottom: 8),
      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
      decoration: BoxDecoration(
        color: isCompleted
            ? Colors.green.shade50
            : theme.colorScheme.surface,
        borderRadius: BorderRadius.circular(8),
        border: Border.all(
          color: theme.colorScheme.outlineVariant.withValues(alpha: 0.2),
        ),
      ),
      child: Row(
        children: [
          // Status dot
          _buildStatusDot(phase.status, colorScheme),
          const SizedBox(width: 12),

          // Phase name
          Expanded(
            child: Text(
              phase.name,
              style: theme.textTheme.bodyMedium?.copyWith(
                color: isCompleted
                    ? Colors.green.shade700
                    : theme.colorScheme.onSurface,
              ),
            ),
          ),

          // Status text
          _buildStatusText(phase, colorScheme),
        ],
      ),
    );
  }

  Widget _buildStatusDot(SyncPhaseStatus status, ColorScheme colorScheme) {
    Color dotColor;
    List<BoxShadow>? shadow;

    switch (status) {
      case SyncPhaseStatus.waiting:
        dotColor = colorScheme.outlineVariant;
        break;
      case SyncPhaseStatus.downloading:
      case SyncPhaseStatus.processing:
        dotColor = colorScheme.secondary;
        shadow = [
          BoxShadow(
            color: colorScheme.secondary.withValues(alpha: 0.5),
            blurRadius: 6,
          ),
        ];
        break;
      case SyncPhaseStatus.completed:
        dotColor = Colors.green;
        shadow = [
          BoxShadow(
            color: Colors.green.withValues(alpha: 0.5),
            blurRadius: 6,
          ),
        ];
    }

    return AnimatedContainer(
      duration: const Duration(milliseconds: 300),
      width: 10,
      height: 10,
      decoration: BoxDecoration(
        shape: BoxShape.circle,
        color: dotColor,
        boxShadow: shadow,
      ),
    );
  }

  Widget _buildStatusText(SyncPhaseInfo phase, ColorScheme colorScheme) {
    Color textColor;
    switch (phase.status) {
      case SyncPhaseStatus.waiting:
        textColor = colorScheme.onSurfaceVariant;
        break;
      case SyncPhaseStatus.downloading:
      case SyncPhaseStatus.processing:
        textColor = colorScheme.secondary;
        break;
      case SyncPhaseStatus.completed:
        textColor = Colors.green.shade600;
        break;
    }

    return Container(
      constraints: const BoxConstraints(minWidth: 140),
      child: Text(
        phase.statusText,
        textAlign: TextAlign.end,
        style: GoogleFonts.jetBrainsMono(
          fontSize: 11,
          fontWeight: FontWeight.w500,
          color: textColor,
          letterSpacing: -0.3,
        ),
      ),
    );
  }

  Widget _buildErrorCard(
    BuildContext context,
    SyncState syncState,
    ColorScheme colorScheme,
  ) {
    return Card(
      color: colorScheme.errorContainer,
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Row(
          children: [
            Icon(
              Icons.error_outline,
              color: colorScheme.onErrorContainer,
            ),
            const SizedBox(width: 12),
            Expanded(
              child: Text(
                syncState.error!,
                style: TextStyle(color: colorScheme.onErrorContainer),
              ),
            ),
          ],
        ),
      ),
    );
  }
}