import 'package:fl_chart/fl_chart.dart';
import 'package:flutter/material.dart';
import 'package:inventory_monitor_app/models/dashboard_models.dart';
import 'package:inventory_monitor_app/services/api_service.dart';
import 'package:inventory_monitor_app/widgets/chart_card.dart';
import 'package:inventory_monitor_app/widgets/kpi_card.dart';

class DashboardScreen extends StatefulWidget {
  const DashboardScreen({super.key});

  @override
  State<DashboardScreen> createState() => _DashboardScreenState();
}

class _DashboardScreenState extends State<DashboardScreen> {
  final ApiService _apiService = ApiService();
  late Future<DashboardSummary> _summaryFuture;
  late Future<List<ChartDataPoint>> _osDistributionFuture;
  late Future<Map<String, double>> _storageFuture;
  late Future<List<ChartDataPoint>> _adminsFuture;

  @override
  void initState() {
    super.initState();
    _summaryFuture = _apiService.getDashboardSummary();
    _osDistributionFuture = _apiService.getOsDistribution();
    _storageFuture = _apiService.getStorageByType();
    _adminsFuture = _apiService.getTopAdminAccounts();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: SingleChildScrollView(
        padding: const EdgeInsets.all(16.0),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            _buildKpiSection(),
            const SizedBox(height: 24),
            _buildChartSection(),
          ],
        ),
      ),
    );
  }

  Widget _buildKpiSection() {
    return FutureBuilder<DashboardSummary>(
      future: _summaryFuture,
      builder: (context, snapshot) {
        if (snapshot.connectionState == ConnectionState.waiting) {
          return const Center(child: CircularProgressIndicator());
        }
        if (snapshot.hasError) {
          return Center(child: Text('Error: ${snapshot.error}'));
        }
        if (!snapshot.hasData) {
          return const Center(child: Text('No summary data available.'));
        }

        final summary = snapshot.data!;
        return Wrap(
          spacing: 16,
          runSpacing: 16,
          children: [
            KpiCard(
                title: 'Total Devices',
                value: summary.totalDevices.toString(),
                icon: Icons.devices),
            KpiCard(
                title: 'Laptops',
                value: summary.totalLaptops.toString(),
                icon: Icons.laptop),
            KpiCard(
                title: 'Desktops',
                value: summary.totalDesktops.toString(),
                icon: Icons.desktop_windows),
            KpiCard(
                title: 'Servers',
                value: summary.totalServers.toString(),
                icon: Icons.dns),
            KpiCard(
                title: 'Printers w/ SN',
                value: summary.printersWithSerial.toString(),
                icon: Icons.print),
            KpiCard(
                title: 'Drives Failing',
                value: summary.drivesFailing.toString(),
                icon: Icons.error_outline,
                color: Colors.red.shade700),
          ],
        );
      },
    );
  }

  Widget _buildChartSection() {
    return LayoutBuilder(
      builder: (context, constraints) {
        final crossAxisCount = constraints.maxWidth > 1200 ? 2 : 1;
        return GridView.count(
          crossAxisCount: crossAxisCount,
          shrinkWrap: true,
          physics: const NeverScrollableScrollPhysics(),
          crossAxisSpacing: 16,
          mainAxisSpacing: 16,
          childAspectRatio: 1.8,
          children: [
            _buildDeviceTypeChart(),
            _buildOsDistributionChart(),
            _buildStorageChart(),
            _buildAdminAccountsChart(),
          ],
        );
      },
    );
  }

  Widget _buildDeviceTypeChart() {
    return FutureBuilder<DashboardSummary>(
      future: _summaryFuture,
      builder: (context, snapshot) {
        if (!snapshot.hasData)
          return const ChartCard(
              title: 'Devices by Type',
              child: Center(child: CircularProgressIndicator()));
        final summary = snapshot.data!;
        return ChartCard(
          title: 'Devices by Type',
          child: PieChart(
            PieChartData(
              sections: [
                PieChartSectionData(
                    value: summary.totalLaptops.toDouble(),
                    title: 'Laptops',
                    color: Colors.blue,
                    radius: 50),
                PieChartSectionData(
                    value: summary.totalDesktops.toDouble(),
                    title: 'Desktops',
                    color: Colors.green,
                    radius: 50),
                PieChartSectionData(
                    value: summary.totalServers.toDouble(),
                    title: 'Servers',
                    color: Colors.orange,
                    radius: 50),
              ],
            ),
          ),
        );
      },
    );
  }

  Widget _buildOsDistributionChart() {
    return FutureBuilder<List<ChartDataPoint>>(
      future: _osDistributionFuture,
      builder: (context, snapshot) {
        if (!snapshot.hasData)
          return const ChartCard(
              title: 'OS Distribution',
              child: Center(child: CircularProgressIndicator()));
        final data = snapshot.data!;
        return ChartCard(
          title: 'OS Distribution',
          child: BarChart(
            BarChartData(
              barGroups: data.asMap().entries.map((entry) {
                return BarChartGroupData(x: entry.key, barRods: [
                  BarChartRodData(
                      toY: entry.value.count.toDouble(), color: Colors.purple)
                ]);
              }).toList(),
              titlesData: FlTitlesData(
                bottomTitles: AxisTitles(
                    sideTitles: SideTitles(
                        showTitles: true,
                        getTitlesWidget: (value, meta) => Text(
                            data[value.toInt()].label.split(' ').last,
                            style: const TextStyle(fontSize: 10)),
                        reservedSize: 40)),
                leftTitles: const AxisTitles(
                    sideTitles: SideTitles(showTitles: true, reservedSize: 40)),
                topTitles:
                    const AxisTitles(sideTitles: SideTitles(showTitles: false)),
                rightTitles:
                    const AxisTitles(sideTitles: SideTitles(showTitles: false)),
              ),
            ),
          ),
        );
      },
    );
  }

  Widget _buildStorageChart() {
    return FutureBuilder<Map<String, double>>(
      future: _storageFuture,
      builder: (context, snapshot) {
        if (!snapshot.hasData)
          return const ChartCard(
              title: 'Total Storage (TB)',
              child: Center(child: CircularProgressIndicator()));
        final data = snapshot.data!;
        return ChartCard(
          title: 'Total Storage (TB)',
          child: BarChart(BarChartData(
            barGroups: [
              BarChartGroupData(x: 0, barRods: [
                BarChartRodData(
                    toY: data['ssd']!, color: Colors.cyan, width: 40)
              ], showingTooltipIndicators: [
                0
              ]),
              BarChartGroupData(x: 1, barRods: [
                BarChartRodData(
                    toY: data['hdd']!, color: Colors.amber, width: 40)
              ], showingTooltipIndicators: [
                0
              ]),
            ],
            titlesData: FlTitlesData(
                bottomTitles: AxisTitles(
                    sideTitles: SideTitles(
                        showTitles: true,
                        getTitlesWidget: (value, meta) =>
                            Text(value == 0 ? 'SSD' : 'HDD')))),
          )),
        );
      },
    );
  }

  Widget _buildAdminAccountsChart() {
    return FutureBuilder<List<ChartDataPoint>>(
      future: _adminsFuture,
      builder: (context, snapshot) {
        if (!snapshot.hasData)
          return const ChartCard(
              title: 'Top 5 Local Admins',
              child: Center(child: CircularProgressIndicator()));
        final data = snapshot.data!;
        return ChartCard(
          title: 'Top 5 Local Admins',
          child: BarChart(BarChartData(
            barGroups: data
                .asMap()
                .entries
                .map((e) => BarChartGroupData(x: e.key, barRods: [
                      BarChartRodData(
                          toY: e.value.count.toDouble(), color: Colors.teal)
                    ]))
                .toList(),
            titlesData: FlTitlesData(
                bottomTitles: AxisTitles(
                    sideTitles: SideTitles(
                        showTitles: true,
                        getTitlesWidget: (value, meta) => Text(
                            data[value.toInt()].label,
                            style: const TextStyle(fontSize: 10)),
                        reservedSize: 40))),
          )),
        );
      },
    );
  }
}