// Guided-setup wizard. Collects scenario / intent / target (plus two
// adaptive toggles) across three explained steps, then previews the
// assembled plan in localized PLAIN LANGUAGE and applies it. All the
// policy lives in the Rust deterministic engine
// (chain_core::guided_setup); this is a thin UI over `chain init`.
//
// The preview is rendered from `chain init --answers … --plan-json`
// (a structured SetupPlan), so the operator sees a German/English
// plain-language summary — never the CLI's English prose. Every
// option carries a one-line explanation of what it configures.

import 'dart:async' show unawaited;
import 'dart:convert';
import 'dart:io';

import 'package:flutter/material.dart';

import '../data/error_presentation.dart';
import '../data/friendly_error.dart';
import '../data/hub.dart';
import '../data/system_actions.dart';
import '../l10n/app_localizations.dart';
import '../main.dart' show StudioShellState;
import '../theme/tokens.dart';
import 'chain_stores_dialog.dart';

/// Allowed wire values per answer — an AI suggestion is validated
/// against these; anything else is rejected as a parse failure so a
/// hallucinated enum can never reach the engine.
const _kScenarioValues = [
  'trying-out',
  'team-hub',
  'regulated-production',
  'building-modules',
];
const _kIntentValues = [
  'hello-world',
  'extract-text',
  'extract-summarize',
  'classify-documents',
  'build-module',
];
const _kTargetValues = [
  'this-laptop',
  'home-server',
  'air-gapped-server',
  'container',
];

/// Extract + validate the system AI's setup suggestion: the first
/// JSON object in [text] with valid enum values for all three
/// answers. Returns null when nothing safe could be parsed.
@visibleForTesting
Map<String, dynamic>? parseSetupSuggestion(String text) {
  final start = text.indexOf('{');
  final end = text.lastIndexOf('}');
  if (start < 0 || end <= start) return null;
  final Object? decoded;
  try {
    decoded = jsonDecode(text.substring(start, end + 1));
  } on FormatException {
    return null;
  }
  if (decoded is! Map<String, dynamic>) return null;
  final scenario = decoded['scenario'];
  final intent = decoded['intent'];
  final target = decoded['target'];
  if (!_kScenarioValues.contains(scenario) ||
      !_kIntentValues.contains(intent) ||
      !_kTargetValues.contains(target)) {
    return null;
  }
  return {
    'scenario': scenario,
    'intent': intent,
    'target': target,
    'require_approval': decoded['require_approval'] == true,
    'data_must_stay_local': decoded['data_must_stay_local'] == true,
  };
}

/// A selectable setup option: the stable kebab wire value plus the
/// localized label + one-line explanation resolved at build time.
class _Option {
  final String value;
  final String Function(AppLocalizations) label;
  final String Function(AppLocalizations) sub;
  const _Option(this.value, this.label, this.sub);
}

class GuidedSetupDialog extends StatefulWidget {
  /// The shell, resolved by [show] before the dialog route detaches
  /// from the shell's subtree. Drives the post-apply "open the
  /// starter flow" navigation; null in tests.
  final StudioShellState? shell;

  /// Test seam: start on the review step with this parsed plan
  /// instead of shelling out to `chain init --plan-json`.
  @visibleForTesting
  final Map<String, dynamic>? debugPlan;

  /// Test seam: combined with [debugPlan], start in the applied
  /// (next-steps) state.
  @visibleForTesting
  final bool debugApplied;

  /// Test seam: skip the live system-AI probe so the free-text
  /// section renders its deterministic "no AI configured" state.
  @visibleForTesting
  final bool debugSkipAiProbe;

  /// Test seam: replaces the hub-first plan preview (a live gRPC
  /// call) so widget tests can drive the CLI fallback — or return a
  /// canned plan — without a hub.
  @visibleForTesting
  static Future<Map<String, dynamic>> Function()? debugPlanViaHubOverride;

  /// Render as page content instead of an [AlertDialog] — used by
  /// the first-run gate, where the wizard IS the screen.
  final bool embedded;

  /// Called instead of popping a dialog route when the wizard is
  /// [embedded] (the gate owns what comes next). Also invoked after
  /// a completed setup so the gate can enter the app.
  final VoidCallback? onFinished;

  const GuidedSetupDialog({
    super.key,
    this.shell,
    this.debugPlan,
    this.debugApplied = false,
    this.debugSkipAiProbe = false,
    this.embedded = false,
    this.onFinished,
  });

  static Future<void> show(BuildContext context) {
    final shell = StudioShellState.of(context);
    // Not barrier-dismissible: a stray click outside the dialog must
    // not throw away a half-answered wizard (and error SnackBars used
    // to lure exactly that click — the operator aimed for the message
    // below the barrier and lost everything). Leaving is explicit:
    // Abbrechen on step 1, Zurück everywhere else.
    return showDialog<void>(
      context: context,
      barrierDismissible: false,
      builder: (_) => GuidedSetupDialog(shell: shell),
    );
  }

  /// Path of the operator dir (`~/.chain`), or null when no home
  /// directory can be resolved.
  static String? _chainDir() {
    final home =
        Platform.environment['HOME'] ?? Platform.environment['USERPROFILE'];
    if (home == null) return null;
    return '$home${Platform.pathSeparator}.chain';
  }

  /// True on a fresh install: neither a config nor a recorded setup
  /// plan exists yet. Drives the welcome page's auto-open.
  static bool isFreshInstall() {
    final dir = _chainDir();
    if (dir == null) return false;
    final sep = Platform.pathSeparator;
    return !File('$dir${sep}config.yaml').existsSync() &&
        !File('$dir${sep}setup-plan.yaml').existsSync();
  }

  /// The `profile:` of the recorded setup plan (`setup-plan.yaml`),
  /// or null when the guided setup never applied one. Lets the
  /// onboarding checklist say "the assistant covered this" instead
  /// of presenting a second, disconnected onboarding surface.
  static String? appliedSetupProfile() {
    final dir = _chainDir();
    if (dir == null) return null;
    final f = File('$dir${Platform.pathSeparator}setup-plan.yaml');
    if (!f.existsSync()) return null;
    try {
      for (final line in f.readAsLinesSync()) {
        final m = RegExp(r'^profile:\s*(\S+)').firstMatch(line.trim());
        if (m != null) return m.group(1);
      }
    } on FileSystemException {
      return null;
    }
    return null;
  }

  @override
  State<GuidedSetupDialog> createState() => _GuidedSetupDialogState();
}

class _GuidedSetupDialogState extends State<GuidedSetupDialog> {
  // Canonical SetupAnswers wire values (serde kebab-case in Rust) with
  // their localized label + explanation.
  static final _scenarios = <_Option>[
    _Option('trying-out', (l) => l.setupScenTryingOut, (l) => l.setupScenTryingOutSub),
    _Option('team-hub', (l) => l.setupScenTeamHub, (l) => l.setupScenTeamHubSub),
    _Option('regulated-production', (l) => l.setupScenRegulated, (l) => l.setupScenRegulatedSub),
    _Option('building-modules', (l) => l.setupScenBuildModules, (l) => l.setupScenBuildModulesSub),
  ];
  static final _intents = <_Option>[
    _Option('hello-world', (l) => l.setupIntentHello, (l) => l.setupIntentHelloSub),
    _Option('extract-text', (l) => l.setupIntentExtract, (l) => l.setupIntentExtractSub),
    _Option('extract-summarize', (l) => l.setupIntentExtractSummarize, (l) => l.setupIntentExtractSummarizeSub),
    _Option('classify-documents', (l) => l.setupIntentClassify, (l) => l.setupIntentClassifySub),
    _Option('build-module', (l) => l.setupIntentBuildModule, (l) => l.setupIntentBuildModuleSub),
  ];
  static final _targets = <_Option>[
    _Option('this-laptop', (l) => l.setupTargetLaptop, (l) => l.setupTargetLaptopSub),
    _Option('home-server', (l) => l.setupTargetHomeServer, (l) => l.setupTargetHomeServerSub),
    _Option('air-gapped-server', (l) => l.setupTargetAirgapped, (l) => l.setupTargetAirgappedSub),
    _Option('container', (l) => l.setupTargetContainer, (l) => l.setupTargetContainerSub),
  ];

  static const _totalSteps = 3; // three answer steps; the review is step 4

  int _step = 0; // 0..2 answers, 3 = review/apply
  String _scenario = 'trying-out';
  String _intent = 'extract-summarize';
  String _target = 'this-laptop';
  bool _requireApproval = false;
  bool _dataLocal = false;
  bool _allowUnsigned = false;
  bool _busy = false;
  Map<String, dynamic>? _plan; // parsed SetupPlan from --plan-json
  bool _applied = false;

  // Post-apply action state: hub reachability + per-module install
  // progress, so the next steps are buttons that report back instead
  // of CLI commands to retype.
  bool _hubUp = false;
  bool _startingHub = false;
  final Set<String> _installing = {};
  final Set<String> _installed = {};

  // Free-text (AI) path state. The menu path is always complete on
  // its own; the AI merely PRE-SELECTS answers for review — it never
  // applies anything (trust rule from guided-setup.md).
  final TextEditingController _goalCtl = TextEditingController();
  SystemAiStatus? _aiStatus; // null until probed / when unreachable
  bool _aiProbed = false;
  bool _suggestBusy = false;
  bool _showReflection = false;

  @override
  void initState() {
    super.initState();
    final seeded = widget.debugPlan;
    if (seeded != null) {
      _plan = seeded;
      _step = _totalSteps;
      _applied = widget.debugApplied;
      _aiProbed = true; // tests: skip the live probe
    } else if (widget.debugSkipAiProbe) {
      _aiProbed = true;
    } else {
      unawaited(_probeAi());
    }
  }

  @override
  void dispose() {
    _goalCtl.dispose();
    try {
      _answersDir?.deleteSync(recursive: true);
    } on FileSystemException {
      // Best-effort cleanup; the OS temp reaper covers the rest.
    }
    super.dispose();
  }

  /// Probe whether a system AI is configured — the free-text path
  /// needs one; without it the menu path stands alone (no dead end).
  Future<void> _probeAi() async {
    SystemAiStatus? status;
    try {
      status = await HubService.instance.systemAiStatus();
    } catch (_) {
      status = null;
    }
    if (!mounted) return;
    setState(() {
      _aiStatus = status;
      _aiProbed = true;
    });
  }

  String _answersYaml() =>
      'scenario: $_scenario\n'
      'intent: $_intent\n'
      'target: $_target\n'
      'require_approval: $_requireApproval\n'
      'data_must_stay_local: $_dataLocal\n'
      'allow_unsigned_modules: $_allowUnsigned\n';

  /// Per-dialog private temp dir for the answers file — a fixed
  /// name in the shared system temp would be world-readable and
  /// racy on multi-user machines. Cleaned up in [dispose].
  Directory? _answersDir;

  String _writeAnswers() {
    // Sync on purpose: the file is a handful of lines, and the async
    // dart:io variants never complete inside the fake-async zone
    // widget tests run in — the wizard would hang there forever.
    _answersDir ??= Directory.systemTemp.createTempSync('chain-setup-');
    final f = File(
      '${_answersDir!.path}${Platform.pathSeparator}answers.yaml',
    );
    f.writeAsStringSync(_answersYaml());
    return f.path;
  }

  /// True when a config file already exists (so applying overwrites it).
  bool _configExists() {
    final home =
        Platform.environment['HOME'] ?? Platform.environment['USERPROFILE'];
    if (home == null) return false;
    final sep = Platform.pathSeparator;
    return File('$home$sep.chain${sep}config.yaml').existsSync();
  }

  Future<void> _goReview() async {
    setState(() {
      _busy = true;
      _plan = null;
    });
    // Preview order matters for trust: try the LIVE HUB first — a
    // pure PlanSetup RPC over the existing connection, no subprocess.
    // The CLI fallback (hub down, first run without a daemon) spawns
    // `chain`, which on macOS can be the app's very first file-system
    // touch and pop a permission prompt; that must never happen
    // BEFORE the operator has seen the plan when a hub is available.
    try {
      final plan = GuidedSetupDialog.debugPlanViaHubOverride != null
          ? await GuidedSetupDialog.debugPlanViaHubOverride!()
          : await HubService.instance.planSetup(
              scenario: _scenario,
              intent: _intent,
              target: _target,
              requireApproval: _requireApproval,
              dataMustStayLocal: _dataLocal,
              allowUnsignedModules: _allowUnsigned,
            );
      if (!mounted) return;
      setState(() {
        _busy = false;
        _plan = plan;
        _step = _totalSteps; // review
      });
      return;
    } catch (_) {
      // Hub unreachable / RPC unavailable — fall through to the CLI.
    }
    final path = _writeAnswers();
    final r = await SystemActions.chainInit(['--answers', path, '--plan-json']);
    if (!mounted) return;
    setState(() => _busy = false);
    if (r.ok) {
      try {
        final plan = jsonDecode(r.stdout.trim()) as Map<String, dynamic>;
        setState(() {
          _plan = plan;
          _step = _totalSteps; // review
        });
      } catch (_) {
        await _showCliError('chain init --plan-json', r.stdout, r.stderr);
      }
    } else {
      await _showCliError('chain init --plan-json', r.stdout, r.stderr);
    }
  }

  /// Surface a failed `chain init` call as a modal dialog stacked
  /// ABOVE this wizard. A SnackBar would land BEHIND the wizard's
  /// modal barrier: visible but dimmed, its copy button unreachable —
  /// and the operator's attempt to click it hits the barrier instead.
  /// Known failure shapes get a localized plain-language headline;
  /// the verbatim CLI output stays copyable behind "Details".
  Future<void> _showCliError(String source, String stdout, String stderr) {
    final l = AppLocalizations.of(context)!;
    final raw = [
      stderr.trim(),
      stdout.trim(),
    ].where((s) => s.isNotEmpty).join('\n\n');
    final bin = SystemActions.resolvedChainBinary();
    final FriendlyError friendly;
    if (stderr.trim() == kFaiBinaryNotFound) {
      // Sentinel, never shown verbatim (see SystemActions docs).
      friendly = FriendlyError(
        headline: l.setupNoBinary,
        detail: '',
        hint: l.setupNoBinaryHint,
      );
    } else if (raw.contains('unexpected argument')) {
      // Version skew: this Studio speaks a newer `chain init` dialect
      // than the binary it found (e.g. a stale build behind a channel
      // symlink). Name the binary and the way out instead of leaking
      // a raw clap usage error.
      friendly = FriendlyError(
        headline: l.setupCliTooOld,
        detail: raw,
        hint: l.setupCliTooOldHint(bin ?? 'chain'),
      );
    } else {
      friendly = FriendlyError(
        headline: source == 'chain init --apply'
            ? l.setupApplyFailed
            : l.setupPreviewFailed,
        detail: raw.isEmpty ? 'process exited non-zero (no output)' : raw,
        hint: bin == null ? null : l.setupCliUsedBinary(bin),
      );
    }
    return showChainErrorDialog(context, source, friendly);
  }

  /// Physical location of the resolved `chain` binary (symlinks
  /// followed) — the path that decides whether macOS shows a folder-
  /// permission prompt when Studio executes it, regardless of how
  /// harmless the symlink's own path looks.
  String? _physicalChainBinary() {
    final bin = SystemActions.resolvedChainBinary();
    if (bin == null) return null;
    try {
      return File(bin).resolveSymbolicLinksSync();
    } on FileSystemException {
      return bin;
    }
  }

  /// True when executing the resolved binary can trigger a macOS
  /// folder-permission (TCC) prompt because it physically lives in a
  /// protected folder. The wizard says so BEFORE the first exec —
  /// an unexplained "Studio wants access to Documents" prompt in the
  /// middle of setup reads as a trust break.
  bool _binaryNeedsFolderPermission() {
    if (!Platform.isMacOS) return false;
    final physical = _physicalChainBinary();
    final home = Platform.environment['HOME'];
    if (physical == null || home == null || home.isEmpty) return false;
    return physical.startsWith('$home/Documents/') ||
        physical.startsWith('$home/Desktop/') ||
        physical.startsWith('$home/Downloads/');
  }

  /// Warning lines the apply emitted on success (e.g. the empty
  /// trusted_publishers caveat). Swallowing them made the wizard
  /// claim more than the config delivers — show them instead.
  String _applyWarnings = '';

  Future<void> _apply() async {
    setState(() => _busy = true);
    final path = _writeAnswers();
    final r = await SystemActions.chainInit(
      ['--answers', path, '--apply', '--force'],
    );
    if (!mounted) return;
    setState(() => _busy = false);
    if (r.ok) {
      final warnings = r.stderr
          .split('\n')
          .where((line) => line.toLowerCase().contains('warn'))
          .join('\n')
          .trim();
      setState(() {
        _applied = true;
        _applyWarnings = warnings;
      });
      unawaited(_probeHub());
    } else {
      await _showCliError('chain init --apply', r.stdout, r.stderr);
    }
  }

  /// Refresh the "is the hub reachable" signal driving the
  /// post-apply action rows.
  Future<void> _probeHub() async {
    final up = await HubService.instance
        .healthy()
        .catchError((Object _) => false);
    if (mounted) setState(() => _hubUp = up);
  }

  /// Start the local daemon, then poll until it answers (the start
  /// command returns before the gRPC endpoint is up). A failed start
  /// often just means "already running", so probe before reporting.
  Future<void> _startHub() async {
    setState(() => _startingHub = true);
    final r = await SystemActions.chainDaemon(['start']);
    var up = false;
    for (var i = 0; i < 6 && !up; i++) {
      await Future<void>.delayed(const Duration(milliseconds: 700));
      up = await HubService.instance
          .healthy()
          .catchError((Object _) => false);
    }
    if (!mounted) return;
    setState(() {
      _startingHub = false;
      _hubUp = up;
    });
    if (!up) {
      await showFaiProcessErrorDialog(
        context,
        'chain daemon start',
        r.stdout,
        r.stderr,
      );
    }
  }

  /// Structured prompt for the system AI. English, fixed shape, and
  /// the reply is validated against the enum whitelists — the model
  /// only ever pre-selects menu answers, it cannot inject config.
  String _suggestionPrompt(String goal) =>
      'You configure the Ch∆In workflow platform. Map the operator\'s '
      'goal to setup answers.\n'
      'Goal: """$goal"""\n'
      'Reply with ONLY one JSON object, no prose, of this exact shape:\n'
      '{"scenario":"trying-out|team-hub|regulated-production|building-modules",'
      '"intent":"hello-world|extract-text|extract-summarize|classify-documents|build-module",'
      '"target":"this-laptop|home-server|air-gapped-server|container",'
      '"require_approval":true|false,"data_must_stay_local":true|false}\n'
      'Pick the closest match for each field.';

  /// Ask the system AI to map the free-text goal onto the menu
  /// answers, then show the editable reflection. Never applies —
  /// the suggestion only pre-selects; preview + apply stay manual.
  Future<void> _suggest() async {
    final goal = _goalCtl.text.trim();
    if (goal.isEmpty) return;
    setState(() => _suggestBusy = true);
    final l = AppLocalizations.of(context)!;
    try {
      final r = await HubService.instance.askAi(_suggestionPrompt(goal));
      if (!mounted) return;
      setState(() => _suggestBusy = false);
      if (r.errorKind.isNotEmpty) {
        await showChainErrorDialog(context, 'system-ai', r.text);
        return;
      }
      final parsed = parseSetupSuggestion(r.text);
      if (parsed == null) {
        await showChainErrorDialog(
          context,
          'system-ai',
          '${l.setupFreeTextParseError}\n\n${r.text}',
        );
        return;
      }
      setState(() {
        _scenario = parsed['scenario'] as String;
        _intent = parsed['intent'] as String;
        _target = parsed['target'] as String;
        _requireApproval = parsed['require_approval'] as bool;
        _dataLocal = parsed['data_must_stay_local'] as bool;
        _showReflection = true;
      });
    } catch (e) {
      if (!mounted) return;
      setState(() => _suggestBusy = false);
      await showChainErrorDialog(context, 'system-ai', e);
    }
  }

  /// Install one plan module by capability name — the hub resolves
  /// the bundle URL from its store index.
  Future<void> _install(String module) async {
    setState(() => _installing.add(module));
    try {
      await HubService.instance.installModule(source: module);
      if (mounted) setState(() => _installed.add(module));
    } catch (e) {
      if (mounted) {
        await showChainErrorDialog(context, 'install $module', e);
      }
    } finally {
      if (mounted) setState(() => _installing.remove(module));
    }
  }

  /// Leave the wizard: pop the dialog route, or — embedded full
  /// screen in the first-run gate, where there is no route to pop —
  /// hand control back to the gate.
  void _close() {
    final onFinished = widget.onFinished;
    if (onFinished != null) {
      onFinished();
    } else {
      Navigator.of(context).pop();
    }
  }

  @override
  Widget build(BuildContext context) {
    final l = AppLocalizations.of(context)!;
    final reviewing = _step >= _totalSteps;
    final title = reviewing
        ? l.setupReviewTitle
        : _showReflection
        ? l.setupReflectionTitle
        : _stepTitle(l);
    final body = SingleChildScrollView(
      child: reviewing
          ? _reviewStep(l)
          : _showReflection
          ? _reflectionView(l)
          : _answerStep(l),
    );
    if (widget.embedded) {
      // First-run gate: same content as the dialog, hosted as a
      // full page instead of a modal over an app that isn't set
      // up yet ("setup after the app runs" reads backwards).
      final theme = Theme.of(context);
      return Column(
        mainAxisSize: MainAxisSize.min,
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(title, style: theme.textTheme.headlineSmall),
          const SizedBox(height: ChainSpace.md),
          Flexible(child: body),
          const SizedBox(height: ChainSpace.md),
          Row(
            mainAxisAlignment: MainAxisAlignment.end,
            children: [
              for (final a in _actions(l)) ...[
                const SizedBox(width: ChainSpace.sm),
                a,
              ],
            ],
          ),
        ],
      );
    }
    return AlertDialog(
      title: Text(title),
      content: SizedBox(
        width: 480,
        child: body,
      ),
      actions: _actions(l),
    );
  }

  String _stepTitle(AppLocalizations l) => switch (_step) {
    0 => l.setupStep1Title,
    1 => l.setupStep2Title,
    _ => l.setupStep3Title,
  };

  Widget _answerStep(AppLocalizations l) {
    final (options, selected, onSelect) = switch (_step) {
      0 => (_scenarios, _scenario, (String v) => setState(() => _scenario = v)),
      1 => (_intents, _intent, (String v) => setState(() => _intent = v)),
      _ => (_targets, _target, (String v) => setState(() => _target = v)),
    };
    return Column(
      mainAxisSize: MainAxisSize.min,
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Padding(
          padding: const EdgeInsets.only(bottom: ChainSpace.sm),
          child: Text(
            l.setupStepOf(_step + 1, _totalSteps),
            style: Theme.of(context).textTheme.labelSmall?.copyWith(
              color: Theme.of(context).colorScheme.onSurfaceVariant,
            ),
          ),
        ),
        for (final o in options)
          _OptionCard(
            title: o.label(l),
            subtitle: o.sub(l),
            selected: selected == o.value,
            onTap: () => onSelect(o.value),
          ),
        // The two adaptive toggles live on the last answer step, in
        // plain language (no "air-gapped" jargon).
        if (_step == 2) ...[
          const SizedBox(height: ChainSpace.sm),
          SwitchListTile(
            contentPadding: EdgeInsets.zero,
            title: Text(l.setupApprovalPlain),
            value: _requireApproval,
            onChanged: (v) => setState(() => _requireApproval = v),
          ),
          SwitchListTile(
            contentPadding: EdgeInsets.zero,
            title: Text(l.setupDataLocalPlain),
            value: _dataLocal,
            onChanged: (v) => setState(() => _dataLocal = v),
          ),
          // Exec transparency: the next click runs the `chain` binary.
          // Say which one — and warn when its physical location will
          // make macOS ask for folder access, so the prompt (if any)
          // arrives explained instead of as a trust break.
          const SizedBox(height: ChainSpace.sm),
          if (!SystemActions.chainBinaryExists())
            _hintRow(l.setupNoBinaryStepHint)
          else ...[
            _hintRow(l.setupExecHint(SystemActions.resolvedChainBinary()!)),
            if (_binaryNeedsFolderPermission())
              _hintRow(l.setupExecHintTcc(_physicalChainBinary()!)),
          ],
        ],
        // The free-text alternative lives on the first step: describe
        // the goal, the system AI pre-selects the menu answers. Menu
        // path always stands alone (air-gap-safe, no dead end).
        if (_step == 0 && _aiProbed) ...[
          const SizedBox(height: ChainSpace.md),
          Text(
            l.setupChooseFreeText,
            style: Theme.of(context).textTheme.labelLarge,
          ),
          const SizedBox(height: ChainSpace.sm),
          if (_aiStatus?.enabled == true) ...[
            TextField(
              controller: _goalCtl,
              minLines: 2,
              maxLines: 4,
              decoration: InputDecoration(
                hintText: l.setupFreeTextHint,
                border: const OutlineInputBorder(),
              ),
            ),
            const SizedBox(height: ChainSpace.xs),
            // Trust rule: be transparent about where the description
            // goes before the operator types anything sensitive.
            Text(
              _aiIsLocal()
                  ? l.setupFreeTextPrivacyLocal(_aiStatus?.model ?? '')
                  : l.setupFreeTextPrivacyRemote(
                      _aiStatus?.model ?? '',
                      _aiStatus?.provider ?? '',
                    ),
              style: Theme.of(context).textTheme.bodySmall?.copyWith(
                color: Theme.of(context).colorScheme.onSurfaceVariant,
              ),
            ),
            const SizedBox(height: ChainSpace.sm),
            Align(
              alignment: Alignment.centerLeft,
              child: FilledButton.tonalIcon(
                onPressed: _suggestBusy ? null : _suggest,
                icon: _suggestBusy
                    ? const SizedBox(
                        width: 14,
                        height: 14,
                        child: CircularProgressIndicator(strokeWidth: 2),
                      )
                    : const Icon(Icons.auto_awesome, size: 18),
                label: Text(l.setupFreeTextSuggest),
              ),
            ),
          ] else
            _hintRow(l.setupFreeTextUnavailable),
        ],
      ],
    );
  }

  /// True when the configured system AI runs on this machine — the
  /// privacy line says so instead of naming a cloud provider.
  bool _aiIsLocal() {
    final s = _aiStatus;
    if (s == null) return false;
    return s.provider == 'ollama' ||
        s.endpoint.contains('localhost') ||
        s.endpoint.contains('127.0.0.1');
  }

  /// Editable reflection of the AI suggestion: "this is how I read
  /// your task", in the same localized labels the menu uses. The
  /// operator either adjusts (steps, pre-selected) or goes straight
  /// to the same preview the menu path uses. Nothing auto-applies.
  Widget _reflectionView(AppLocalizations l) {
    final theme = Theme.of(context);
    String labelFor(List<_Option> opts, String value) =>
        opts.firstWhere((o) => o.value == value, orElse: () => opts.first)
            .label(l);
    final lines = <String>[
      l.setupReflectionScenario(labelFor(_scenarios, _scenario)),
      l.setupReflectionIntent(labelFor(_intents, _intent)),
      l.setupReflectionTarget(labelFor(_targets, _target)),
      if (_requireApproval) l.setupReflectionApproval,
      if (_dataLocal) l.setupReflectionDataLocal,
    ];
    return Column(
      mainAxisSize: MainAxisSize.min,
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        for (final line in lines)
          Padding(
            padding: const EdgeInsets.only(bottom: 6),
            child: Row(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Text('·  ', style: theme.textTheme.bodyMedium),
                Expanded(
                  child: Text(line, style: theme.textTheme.bodyMedium),
                ),
              ],
            ),
          ),
        const SizedBox(height: ChainSpace.xs),
        Text(
          l.setupReflectionEditHint,
          style: theme.textTheme.bodySmall?.copyWith(
            color: theme.colorScheme.onSurfaceVariant,
          ),
        ),
      ],
    );
  }

  Widget _reviewStep(AppLocalizations l) {
    final plan = _plan;
    if (plan == null) return const SizedBox.shrink();
    final theme = Theme.of(context);
    final lines = _planLines(l, plan);
    final modules = (plan['modules'] as List?)?.cast<String>() ?? const [];
    final airGapped = (plan['profile'] as String? ?? '') == 'air-gapped';
    final sigGate = plan['require_signatures'] == true;
    return Column(
      mainAxisSize: MainAxisSize.min,
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        if (_applied)
          ..._appliedSteps(l, plan)
        else ...[
          for (final line in lines)
            Padding(
              padding: const EdgeInsets.only(bottom: 6),
              child: Row(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Text('·  ', style: theme.textTheme.bodyMedium),
                  Expanded(
                    child: Text(line, style: theme.textTheme.bodyMedium),
                  ),
                ],
              ),
            ),
          // Signature dead end (SEC-01): a regulated connected plan
          // refuses the public store's unsigned bundles — the very
          // installs suggested after apply. Explain it and offer the
          // relaxation as one deliberate, reversible switch. The plan
          // is re-assembled on toggle so the preview stays truthful.
          if (!airGapped && modules.isNotEmpty && (sigGate || _allowUnsigned)) ...[
            const SizedBox(height: ChainSpace.sm),
            if (sigGate)
              Row(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Icon(
                    Icons.verified_user_outlined,
                    size: 16,
                    color: theme.colorScheme.tertiary,
                  ),
                  const SizedBox(width: 6),
                  Expanded(
                    child: Text(
                      l.setupSigPublicStoreNotice,
                      style: theme.textTheme.bodySmall?.copyWith(
                        color: theme.colorScheme.tertiary,
                      ),
                    ),
                  ),
                ],
              ),
            SwitchListTile(
              contentPadding: EdgeInsets.zero,
              title: Text(l.setupAllowUnsigned),
              subtitle: Text(l.setupAllowUnsignedSub),
              value: _allowUnsigned,
              onChanged: (v) {
                setState(() => _allowUnsigned = v);
                _goReview();
              },
            ),
          ],
          if (_configExists()) ...[
            const SizedBox(height: ChainSpace.sm),
            Row(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Icon(Icons.info_outline, size: 16, color: theme.colorScheme.tertiary),
                const SizedBox(width: 6),
                Expanded(
                  child: Text(
                    l.setupPlanOverwriteWarn,
                    style: theme.textTheme.bodySmall?.copyWith(
                      color: theme.colorScheme.tertiary,
                    ),
                  ),
                ),
              ],
            ),
          ],
        ],
      ],
    );
  }

  /// Post-apply next steps as real Studio actions: start the hub,
  /// install each plan module, open the starter flow — no CLI text.
  List<Widget> _appliedSteps(AppLocalizations l, Map<String, dynamic> plan) {
    final theme = Theme.of(context);
    final modules = (plan['modules'] as List?)?.cast<String>() ?? const [];
    final airGapped = (plan['profile'] as String? ?? '') == 'air-gapped';
    final sigGate = plan['require_signatures'] == true;
    final flow = plan['starter_flow'] as String? ?? '';
    return [
      Row(
        children: [
          Icon(Icons.check_circle, color: ChainColors.success, size: 20),
          const SizedBox(width: ChainSpace.sm),
          Text(l.setupApplied, style: theme.textTheme.titleSmall),
        ],
      ),
      const SizedBox(height: ChainSpace.md),
      Text(l.setupNextTitle, style: theme.textTheme.labelLarge),
      const SizedBox(height: ChainSpace.sm),
      // 1 — the hub. Everything else needs it.
      if (_hubUp)
        _doneRow(l.setupHubRunning)
      else
        _actionRow(
          FilledButton.tonalIcon(
            onPressed: _startingHub ? null : _startHub,
            icon: _startingHub
                ? const SizedBox(
                    width: 14,
                    height: 14,
                    child: CircularProgressIndicator(strokeWidth: 2),
                  )
                : const Icon(Icons.play_arrow, size: 18),
            label: Text(l.setupNextHubStart),
          ),
        ),
      // 2 — the plan's modules. On a signature-strict plan the path
      // stays clickable: add a signed source (the stores dialog with
      // its pin-a-key field), then install — no terminal, no dead end.
      if (modules.isNotEmpty) ...[
        if (airGapped)
          _hintRow(l.setupModulesOfflineHint)
        else ...[
          if (sigGate) ...[
            _hintRow(l.setupModulesSignedHint),
            _hintRow(l.setupTrustedPublishersHint),
            _actionRow(
              OutlinedButton.icon(
                onPressed: () => ChainStoresDialog.show(context),
                icon: const Icon(Icons.add_moderator_outlined, size: 18),
                label: Text(l.setupAddSignedSource),
              ),
            ),
          ],
          if (!_hubUp) _hintRow(l.setupStartHubFirst),
          for (final m in modules)
            _installed.contains(m)
                ? _doneRow(l.setupActionInstalled(m))
                : _actionRow(
                    FilledButton.tonalIcon(
                      onPressed: (!_hubUp || _installing.contains(m))
                          ? null
                          : () => _install(m),
                      icon: _installing.contains(m)
                          ? const SizedBox(
                              width: 14,
                              height: 14,
                              child: CircularProgressIndicator(strokeWidth: 2),
                            )
                          : const Icon(Icons.download, size: 18),
                      label: Text(l.setupActionInstall(m)),
                    ),
                  ),
        ],
      ],
      // 3 — the starter flow (auto-imported on first hub start).
      if (flow.isNotEmpty)
        _actionRow(
          OutlinedButton.icon(
            onPressed: () {
              _close();
              widget.shell?.navigateTo('flows');
            },
            icon: const Icon(Icons.account_tree_outlined, size: 18),
            label: Text(l.setupActionOpenFlow(flow)),
          ),
        ),
      // Honesty: warnings the apply emitted (e.g. the empty
      // trusted-publishers caveat), selectable so they can go
      // verbatim into a compliance note.
      if (_applyWarnings.isNotEmpty) ...[
        const SizedBox(height: ChainSpace.sm),
        Text(l.setupApplyNotes, style: theme.textTheme.labelLarge),
        const SizedBox(height: 4),
        SelectableText(
          _applyWarnings,
          style: theme.textTheme.bodySmall?.copyWith(
            color: theme.colorScheme.onSurfaceVariant,
          ),
        ),
      ],
    ];
  }

  Widget _actionRow(Widget child) => Padding(
    padding: const EdgeInsets.only(top: ChainSpace.xs),
    child: Align(alignment: Alignment.centerLeft, child: child),
  );

  Widget _doneRow(String label) => Padding(
    padding: const EdgeInsets.only(top: ChainSpace.xs),
    child: Row(
      children: [
        Icon(Icons.check_circle, size: 18, color: ChainColors.success),
        const SizedBox(width: 6),
        Expanded(
          child: Text(label, style: Theme.of(context).textTheme.bodyMedium),
        ),
      ],
    ),
  );

  Widget _hintRow(String text) => Padding(
    padding: const EdgeInsets.only(top: ChainSpace.xs),
    child: Row(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Icon(
          Icons.info_outline,
          size: 16,
          color: Theme.of(context).colorScheme.onSurfaceVariant,
        ),
        const SizedBox(width: 6),
        Expanded(
          child: Text(
            text,
            style: Theme.of(context).textTheme.bodySmall?.copyWith(
              color: Theme.of(context).colorScheme.onSurfaceVariant,
            ),
          ),
        ),
      ],
    ),
  );

  /// Build the localized plain-language plan lines from the structured
  /// SetupPlan (never the CLI prose).
  List<String> _planLines(AppLocalizations l, Map<String, dynamic> plan) {
    final profile = plan['profile'] as String? ?? '';
    final lines = <String>[];
    switch (profile) {
      case 'air-gapped':
        lines.add(l.setupPlanIntroAirgapped);
      case 'enterprise':
        lines.add(l.setupPlanIntroEnterprise);
      default:
        lines.add(l.setupPlanIntroDev);
    }
    // Where this actually lands: the wizard always configures the
    // machine Studio runs on — say so, especially when the operator
    // picked a server/container target.
    switch (plan['runbook'] as String? ?? '') {
      case 'service':
        lines.add(l.setupPlanRunbookService);
      case 'air-gap-transfer':
        lines.add(l.setupPlanRunbookAirgap);
      case 'container':
        lines.add(l.setupPlanRunbookContainer);
      default:
        lines.add(l.setupPlanRunbookLocal);
    }
    if (plan['require_signatures'] == true) lines.add(l.setupPlanSignatures);
    // The audit chain is always on for regulated profiles — the
    // scenario card promises a tamper-evident log, so the preview
    // states what is delivered (and the WORM line covers the rest).
    if (profile == 'enterprise' || profile == 'air-gapped') {
      lines.add(l.setupPlanAuditChain);
    }
    if (plan['worm_audit'] == true) lines.add(l.setupPlanWorm);
    if (plan['approval_step'] == true) lines.add(l.setupPlanApproval);
    final modules = (plan['modules'] as List?)?.cast<String>() ?? const [];
    if (modules.isNotEmpty) lines.add(l.setupPlanModules(modules.join(', ')));
    final flow = plan['starter_flow'] as String? ?? '';
    if (flow.isNotEmpty) lines.add(l.setupPlanFlow(flow));
    final docs = (plan['curated_docs'] as List?)?.length ?? 0;
    if (docs > 0) lines.add(l.setupPlanDocs(docs));
    lines.add(l.setupPlanFileChanged('~/.chain/config.yaml'));
    return lines;
  }

  List<Widget> _actions(AppLocalizations l) {
    if (_busy) {
      return const [
        Padding(
          padding: EdgeInsets.all(12),
          child: SizedBox(
            width: 18,
            height: 18,
            child: CircularProgressIndicator(strokeWidth: 2),
          ),
        ),
      ];
    }
    if (_applied) {
      return [
        FilledButton(
          onPressed: _close,
          child: Text(l.guidedSetupClose),
        ),
      ];
    }
    if (_showReflection && _step < _totalSteps) {
      // AI reflection: adjust step-by-step (answers stay pre-selected)
      // or continue to the same preview the menu path uses.
      return [
        TextButton(
          onPressed: () => setState(() => _showReflection = false),
          child: Text(l.setupReflectionAdjust),
        ),
        FilledButton(
          onPressed: () {
            setState(() => _showReflection = false);
            _goReview();
          },
          child: Text(l.setupReflectionToPreview),
        ),
      ];
    }
    if (_step < _totalSteps) {
      return [
        TextButton(
          onPressed: _step == 0
              ? _close
              : () => setState(() => _step -= 1),
          child: Text(_step == 0 ? l.guidedSetupCancel : l.guidedSetupBack),
        ),
        FilledButton(
          onPressed: _step < _totalSteps - 1
              ? () => setState(() => _step += 1)
              : _goReview,
          child: Text(l.guidedSetupNext),
        ),
      ];
    }
    // Review step.
    return [
      TextButton(
        onPressed: () => setState(() => _step = _totalSteps - 1),
        child: Text(l.guidedSetupBack),
      ),
      FilledButton(onPressed: _apply, child: Text(l.guidedSetupApply)),
    ];
  }
}

/// A selectable card: title + one-line explanation, highlighted when
/// selected. Replaces the bare dropdowns so every choice explains
/// itself in place (zero-learning-curve).
class _OptionCard extends StatelessWidget {
  final String title;
  final String subtitle;
  final bool selected;
  final VoidCallback onTap;

  const _OptionCard({
    required this.title,
    required this.subtitle,
    required this.selected,
    required this.onTap,
  });

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final accent = theme.colorScheme.primary;
    return Padding(
      padding: const EdgeInsets.only(bottom: ChainSpace.sm),
      child: Material(
        color: selected
            ? accent.withValues(alpha: 0.10)
            : theme.colorScheme.surfaceContainerHighest,
        borderRadius: BorderRadius.circular(ChainRadius.md),
        child: InkWell(
          borderRadius: BorderRadius.circular(ChainRadius.md),
          onTap: onTap,
          child: Container(
            padding: const EdgeInsets.symmetric(
              horizontal: ChainSpace.md,
              vertical: ChainSpace.sm,
            ),
            decoration: BoxDecoration(
              borderRadius: BorderRadius.circular(ChainRadius.md),
              border: Border.all(
                color: selected ? accent : theme.colorScheme.outlineVariant,
                width: selected ? 1.5 : 1,
              ),
            ),
            child: Row(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Icon(
                  selected
                      ? Icons.radio_button_checked
                      : Icons.radio_button_unchecked,
                  size: 18,
                  color: selected ? accent : theme.colorScheme.onSurfaceVariant,
                ),
                const SizedBox(width: ChainSpace.sm),
                Expanded(
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Text(
                        title,
                        style: theme.textTheme.titleSmall?.copyWith(
                          fontWeight: FontWeight.w600,
                        ),
                      ),
                      const SizedBox(height: 2),
                      Text(
                        subtitle,
                        style: theme.textTheme.bodySmall?.copyWith(
                          color: theme.colorScheme.onSurfaceVariant,
                        ),
                      ),
                    ],
                  ),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}