import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';

import '../../../models/programmer_day_sheet.model.dart';
import '../../../providers/leave_provider.dart';
import '../../../providers/pass_slip_provider.dart';
import '../../../providers/profile_provider.dart';
import '../../../providers/programmer_day_data_provider.dart';
import '../../../providers/programmer_day_sheets_provider.dart';
import '../../../utils/app_time.dart';
import '../../../utils/programmer_daily_time.dart';
import '../../../utils/staff_presence.dart';
import '../../../widgets/app_status_summary.dart';
import '../../../theme/app_status_colors.dart';
import 'help_panel.dart';
import 'monitor_model.dart';
import 'programmer_monitor_card.dart';

/// Summary row + programmer grid + help panel for the Monitor tab.
class MonitorTab extends ConsumerWidget {
  const MonitorTab({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    // Tick every 30 s to keep durations fresh.
    final now = ref.watch(clockTickerProvider).valueOrNull ?? AppTime.now();
    final todayKey = ref.watch(todayKeyProvider);
    final profilesAsync = ref.watch(profilesProvider);
    final dayDataAsync = ref.watch(programmerDayDataProvider(todayKey));
    final runStates = ref.watch(programmerRunStatesProvider);
    final leavesAsync = ref.watch(leavesProvider);
    final passSlipsAsync = ref.watch(passSlipsProvider);
    final allSheetsAsync = ref.watch(allDaySheetsProvider);

    final profiles = profilesAsync.valueOrNull ?? [];
    final programmerProfiles =
        profiles.where((p) => p.role == 'programmer').toList();
    final profileNames = <String, String>{
      for (final p in profiles) p.id: p.fullName,
    };

    final leaves = leavesAsync.valueOrNull ?? [];
    final passSlips = passSlipsAsync.valueOrNull ?? [];
    final activeLeaves = activeLeaveByUser(leaves, now);
    final activePassSlips = activePassSlipByUser(passSlips);

    // Build sheetStatusByUser for today: programmerId → status.
    final allSheets = allSheetsAsync.valueOrNull ?? const <ProgrammerDaySheet>[];
    final sheetStatusByUser = <String, String>{};
    var sheetsPending = 0;
    for (final sheet in allSheets) {
      if (sheet.workDate == manilaDay(now)) {
        sheetStatusByUser[sheet.programmerId] = sheet.status;
        if (sheet.status == DaySheetStatus.pending ||
            sheet.status == DaySheetStatus.disapproved) {
          sheetsPending++;
        }
      }
    }

    if (dayDataAsync.isLoading && !dayDataAsync.hasValue) {
      return const Center(child: CircularProgressIndicator());
    }

    final dayData = dayDataAsync.valueOrNull;

    List<ProgrammerMonitorEntry> entries = [];
    if (dayData != null) {
      entries = buildMonitorEntries(
        programmers: programmerProfiles,
        today: dayData,
        runStates: runStates,
        leaves: activeLeaves,
        passSlips: activePassSlips,
        sheetStatusByUser: sheetStatusByUser,
        projectNames: const {},
        profileNames: profileNames,
        now: now,
      );
    }

    // Compute summary counts.
    var working = 0;
    var paused = 0;
    var idle = 0;
    var away = 0;
    for (final e in entries) {
      switch (e.state) {
        case MonitorState.working:
          working++;
        case MonitorState.paused:
          paused++;
        case MonitorState.idle:
          idle++;
        case MonitorState.onLeave:
        case MonitorState.passSlip:
          away++;
      }
    }

    final summaryItems = [
      AppStatusSummaryItem(
        label: 'Working',
        count: working,
        kind: StatusKind.success,
      ),
      AppStatusSummaryItem(
        label: 'Paused',
        count: paused,
        kind: StatusKind.warning,
      ),
      AppStatusSummaryItem(
        label: 'Idle',
        count: idle,
        kind: StatusKind.neutral,
      ),
      AppStatusSummaryItem(
        label: 'Away',
        count: away,
        kind: StatusKind.info,
      ),
      AppStatusSummaryItem(
        label: 'Sheets pending',
        count: sheetsPending,
        kind: StatusKind.warning,
      ),
    ];

    return LayoutBuilder(
      builder: (context, constraints) {
        final width = constraints.maxWidth;
        // Help panel breakpoint: show side-by-side at >= 900.
        final sideBySide = width >= 900;

        final grid = _ProgrammerGrid(
          entries: entries,
          profileNames: profileNames,
          width: sideBySide ? width - 320 : width,
        );

        final body = sideBySide
            ? Row(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Expanded(child: grid),
                  const SizedBox(width: 12),
                  SizedBox(
                    width: 300,
                    child: HelpPanel(profileNames: profileNames),
                  ),
                ],
              )
            : Column(
                children: [
                  grid,
                  const SizedBox(height: 16),
                  SizedBox(
                    height: 340,
                    child: HelpPanel(profileNames: profileNames),
                  ),
                ],
              );

        return Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            AppStatusSummaryRow(
              items: summaryItems,
              padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
            ),
            Expanded(
              child: Padding(
                padding: const EdgeInsets.symmetric(horizontal: 16),
                child: body,
              ),
            ),
          ],
        );
      },
    );
  }
}

class _ProgrammerGrid extends StatelessWidget {
  const _ProgrammerGrid({
    required this.entries,
    required this.profileNames,
    required this.width,
  });

  final List<ProgrammerMonitorEntry> entries;
  final Map<String, String> profileNames;
  final double width;

  @override
  Widget build(BuildContext context) {
    final crossAxisCount = width < 700
        ? 1
        : width < 1100
            ? 2
            : 3;

    if (entries.isEmpty) {
      return const Center(
        child: Padding(
          padding: EdgeInsets.all(24),
          child: Text('No programmers found.'),
        ),
      );
    }

    return GridView.builder(
      shrinkWrap: true,
      physics: const NeverScrollableScrollPhysics(),
      gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
        crossAxisCount: crossAxisCount,
        mainAxisSpacing: 10,
        crossAxisSpacing: 10,
        childAspectRatio: 2.4,
      ),
      itemCount: entries.length,
      itemBuilder: (context, i) {
        final entry = entries[i];
        return ProgrammerMonitorCard(
          entry: entry,
          profileNames: profileNames,
          onTap: () =>
              context.go('/programmer-tasks/programmers/${entry.programmer.id}'),
        );
      },
    );
  }
}