import 'dart:async';

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:stacked/stacked.dart';

import '../../about/external/data/EnvCheck.dart';
import '../../about/internal/application/NotificationType.dart';
import '../../about/internal/application/ServerProfile.dart';
import '../../about/internal/application/StepTracker.dart';
import '../../about/internal/application/TextType.dart';
import '../../comms/Comms.dart' show LogLine;
import '../../designs/LogConsole.dart';
import '../../designs/StepList.dart';
import '../../designs/text/Text.dart';
import '../../utils/Colors.dart';
import 'Configuration.dart';
import 'ConnectConfiguration.dart';
import 'ViewConfiguration.dart';

class ConfigurationState extends State<Configuration>
    implements ConnectConfiguration {
  ViewConfiguration? _model;

  StreamSubscription<LogLine>? _logSub;
  StreamSubscription<List<DeployStep>>? _stepSub;

  final _lines = <LogLine>[];
  List<DeployStep> _steps = [];
  final Map<String, String> _versions = {};

  String _packageManager = 'unknown';
  bool _loading = true;
  String? _error;
  String? _busyKey;

  ServerProfile get _server => widget.server;

  bool _installed(String key) => (_versions[key] ?? '').trim().isNotEmpty;

  @override
  void dispose() {
    _logSub?.cancel();
    _stepSub?.cancel();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return ViewModelBuilder<ViewConfiguration>.reactive(
      viewModelBuilder: () => ViewConfiguration(context, this),
      onViewModelReady: _onReady,
      builder: (context, viewModel, child) => Scaffold(
        appBar: AppBar(
          title: text(
            '${_server.name} · configuration',
            20,
            TextType.Bold,
            color: context.jp.text,
          ),
          actions: [
            IconButton(
              tooltip: 'Re-scan',
              onPressed: _loading || _busyKey != null ? null : _onRescan,
              icon: const Icon(Icons.refresh),
            ),
            const SizedBox(width: 4),
          ],
        ),
        body: ListView(
          padding: const EdgeInsets.fromLTRB(16, 16, 16, 40),
          children: [
            _summaryCard(),
            if (_error != null) ...[const SizedBox(height: 12), _errorCard()],
            const SizedBox(height: 16),
            text(
              'ENVIRONMENT',
              12,
              TextType.Bold,
              color: context.jp.textDim,
              letterSpacing: 1.2,
            ),
            const SizedBox(height: 10),
            LayoutBuilder(
              builder: (context, c) {
                const gap = 12.0;
                final cols = c.maxWidth >= 720 ? 2 : 1;
                final w = (c.maxWidth - gap * (cols - 1)) / cols;
                return Wrap(
                  spacing: gap,
                  runSpacing: gap,
                  children: [
                    for (final tool in kEnvTools)
                      SizedBox(width: w, child: _toolCard(tool)),
                  ],
                );
              },
            ),
            if (_steps.isNotEmpty) ...[
              const SizedBox(height: 22),
              StepList(steps: _steps),
            ],
            if (_lines.isNotEmpty) ...[
              const SizedBox(height: 14),
              LogConsole(
                logs: _lines,
                height: 260,
                onClear: _onClearLogs,
                onCopy: _onCopyLogs,
              ),
            ],
          ],
        ),
      ),
    );
  }

  void _onReady(ViewConfiguration model) {
    _model = model;
    // onViewModelReady fires mid-build; a synchronous setState from the
    // first load would dirty this State while it is still being built.
    WidgetsBinding.instance.addPostFrameCallback((_) {
      if (mounted) _initiate();
    });
  }

  Future<void> _initiate() async {
    _logSub = _model?.logs.listen(_onLogLine);
    _stepSub = _model?.steps.listen(_onSteps);
    _model?.probeEnvironment(_server);
  }

  void _onLogLine(LogLine line) {
    if (!mounted) return;
    setState(() => _lines.add(line));
  }

  void _onSteps(List<DeployStep> steps) {
    if (!mounted) return;
    setState(() => _steps = steps);
  }

  // ── named handlers ─────────────────────────────────────────────────────────

  void _onRescan() {
    setState(() {
      _loading = true;
      _error = null;
    });
    _model?.probeEnvironment(_server);
  }

  void _onInstall(EnvTool tool) =>
      _model?.prepareInstall(tool, _packageManager);

  void _onClearLogs() => setState(() => _lines.clear());

  void _onCopyLogs() {
    Clipboard.setData(
      ClipboardData(text: _lines.map((l) => l.text).join('\n')),
    );
    _notify('Logs copied.');
  }

  void _notify(String message) {
    if (!mounted) return;
    ScaffoldMessenger.of(
      context,
    ).showSnackBar(SnackBar(content: Text(message)));
  }

  // ── ConnectConfiguration ───────────────────────────────────────────────────

  @override
  void onEnvironmentProbed(
    String packageManager,
    Map<String, String> versions,
  ) {
    if (!mounted) return;
    setState(() {
      _packageManager = packageManager;
      _versions
        ..clear()
        ..addAll(versions);
      _loading = false;
      _error = null;
    });
  }

  @override
  void onProbeFailed(String message) {
    if (!mounted) return;
    setState(() {
      _loading = false;
      _error = message;
    });
  }

  @override
  void onInstallCommandReady(EnvTool tool, String command) {
    final sudoNote = _server.useSudo ? ' (via sudo)' : '';
    final unitNote = tool.unit == null
        ? ''
        : '\n\nThen: systemctl enable --now ${tool.unit}';
    _model?.showApplicationNotification(
      NotificationType.info,
      'Install ${tool.label}?',
      'Peach will run$sudoNote:\n\n$command$unitNote',
      true,
      true,
      null,
      action: 'Install',
      positiveAction: () => _onConfirmInstall(tool, command),
    );
  }

  void _onConfirmInstall(EnvTool tool, String command) {
    Navigator.pop(context);
    setState(() {
      _busyKey = tool.key;
      _lines.clear();
    });
    _model?.installTool(_server, tool, command);
  }

  @override
  void onToolInstalled(EnvTool tool, String version) {
    if (!mounted) return;
    setState(() {
      _versions[tool.key] = version;
      _busyKey = null;
    });
  }

  // ── screen-only widgets ────────────────────────────────────────────────────

  Widget _summaryCard() {
    final jp = context.jp;
    final present = kEnvTools.where((t) => _installed(t.key)).length;
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: PeachTheme.panel(context, glowColor: PeachTheme.seed),
      child: Row(
        children: [
          Container(
            width: 46,
            height: 46,
            decoration: BoxDecoration(
              color: PeachTheme.seed.withValues(alpha: 0.14),
              borderRadius: BorderRadius.circular(13),
              border: Border.all(
                color: PeachTheme.seed.withValues(alpha: 0.35),
              ),
            ),
            child: const Icon(Icons.fact_check, color: PeachTheme.seed),
          ),
          const SizedBox(width: 14),
          Expanded(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                text(
                  _loading
                      ? 'Scanning environment…'
                      : '$present / ${kEnvTools.length} tools ready',
                  16,
                  TextType.Bold,
                  color: jp.text,
                ),
                const SizedBox(height: 2),
                text(
                  '${_server.username}@${_server.host}',
                  12,
                  TextType.Regular,
                  color: jp.textDim,
                ),
              ],
            ),
          ),
          _packageManagerChip(),
        ],
      ),
    );
  }

  Widget _packageManagerChip() {
    final jp = context.jp;
    final known = _packageManager != 'unknown';
    final color = known ? PeachTheme.accent : jp.textFaint;
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 5),
      decoration: BoxDecoration(
        color: color.withValues(alpha: 0.14),
        borderRadius: BorderRadius.circular(20),
        border: Border.all(color: color.withValues(alpha: 0.4)),
      ),
      child: Row(
        mainAxisSize: MainAxisSize.min,
        children: [
          Icon(Icons.inventory_2, size: 13, color: color),
          const SizedBox(width: 5),
          text(
            _loading ? '…' : _packageManager,
            11.5,
            TextType.Bold,
            color: color,
          ),
        ],
      ),
    );
  }

  Widget _errorCard() => Container(
    padding: const EdgeInsets.all(14),
    decoration: BoxDecoration(
      color: PeachTheme.danger.withValues(alpha: 0.10),
      borderRadius: BorderRadius.circular(12),
      border: Border.all(color: PeachTheme.danger.withValues(alpha: 0.5)),
    ),
    child: Row(
      children: [
        const Icon(Icons.error_outline, color: PeachTheme.danger),
        const SizedBox(width: 10),
        Expanded(
          child: text(_error!, 14, TextType.Regular, color: PeachTheme.danger),
        ),
      ],
    ),
  );

  Widget _toolCard(EnvTool tool) {
    final jp = context.jp;
    final installed = _installed(tool.key);
    final version = _versions[tool.key]?.trim() ?? '';
    final busy = _busyKey == tool.key;
    final color = installed ? PeachTheme.seed : jp.textFaint;
    return Container(
      padding: const EdgeInsets.all(14),
      decoration: PeachTheme.panel(context, radius: 16),
      child: Row(
        children: [
          Container(
            width: 42,
            height: 42,
            decoration: BoxDecoration(
              color: color.withValues(alpha: 0.14),
              borderRadius: BorderRadius.circular(11),
              border: Border.all(color: color.withValues(alpha: 0.3)),
            ),
            child: Icon(tool.icon, color: color, size: 20),
          ),
          const SizedBox(width: 14),
          Expanded(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                text(tool.label, 15, TextType.Bold, color: jp.text),
                const SizedBox(height: 2),
                text(
                  _loading
                      ? 'checking…'
                      : (installed
                            ? (version.isEmpty ? 'installed' : version)
                            : 'Not installed'),
                  12,
                  TextType.Regular,
                  color: installed ? jp.textDim : jp.textFaint,
                  maxLines: 1,
                  overflow: TextOverflow.ellipsis,
                ),
              ],
            ),
          ),
          const SizedBox(width: 10),
          if (_loading)
            const SizedBox()
          else if (installed)
            const Icon(Icons.check_circle, color: PeachTheme.seed)
          else if (busy)
            const SizedBox(
              width: 22,
              height: 22,
              child: CircularProgressIndicator(strokeWidth: 2),
            )
          else
            OutlinedButton.icon(
              onPressed: _busyKey != null ? null : () => _onInstall(tool),
              icon: const Icon(Icons.download, size: 18),
              label: text('Install', 13, TextType.Bold, color: PeachTheme.seed),
              style: OutlinedButton.styleFrom(
                foregroundColor: PeachTheme.seed,
                side: BorderSide(color: PeachTheme.seed.withValues(alpha: 0.5)),
                padding: const EdgeInsets.symmetric(
                  horizontal: 14,
                  vertical: 10,
                ),
                shape: RoundedRectangleBorder(
                  borderRadius: BorderRadius.circular(10),
                ),
              ),
            ),
        ],
      ),
    );
  }
}