import 'dart:convert';
import 'dart:io';

const supportedThemeSettings = <String>[
  'auto',
  'dark',
  'light',
  'light-daltonized',
  'dark-daltonized',
  'light-ansi',
  'dark-ansi',
];

const supportedThemeNames = <String>[
  'dark',
  'light',
  'light-daltonized',
  'dark-daltonized',
  'light-ansi',
  'dark-ansi',
];

const supportedAgentColors = <String>[
  'red',
  'blue',
  'green',
  'yellow',
  'purple',
  'orange',
  'pink',
  'cyan',
];

const supportedEffortLevels = <String>['low', 'medium', 'high', 'max'];

const supportedPermissionModes = <String>[
  'acceptEdits',
  'auto',
  'bubble',
  'bypassPermissions',
  'default',
  'dontAsk',
  'plan',
];

String getConfigHomeDir() {
  final home = Platform.environment['HOME'];
  if (home == null || home.isEmpty) {
    return joinPath(Directory.current.path, '.clawd_code');
  }

  return joinPath(home, '.clawd_code');
}

String getSettingsFilePath() {
  return joinPath(getConfigHomeDir(), 'settings.json');
}

String getPlansDirectoryPath() {
  return joinPath(getConfigHomeDir(), 'plans');
}

String joinPath(String base, String child) {
  if (base.endsWith(Platform.pathSeparator)) {
    return '$base$child';
  }

  return '$base${Platform.pathSeparator}$child';
}

class LocalSettings {
  const LocalSettings({
    this.advisorModel,
    this.alwaysAllowRules = const <String>[],
    this.alwaysAskRules = const <String>[],
    this.alwaysDenyRules = const <String>[],
    this.editorMode = 'normal',
    this.effortLevel,
    this.fastMode = false,
    this.hooks,
    this.mcpServers,
    this.model,
    this.openRouterApiKey,
    this.outputStyle,
    this.permissionMode = 'default',
    this.privacyLevel,
    this.statusLinePrompt,
    this.telemetry,
    this.theme = 'dark',
  });

  factory LocalSettings.fromJson(Map<String, dynamic> json) {
    return LocalSettings(
      advisorModel: _readString(json, 'advisorModel'),
      alwaysAllowRules: _readStringList(json, 'alwaysAllowRules'),
      alwaysAskRules: _readStringList(json, 'alwaysAskRules'),
      alwaysDenyRules: _readStringList(json, 'alwaysDenyRules'),
      editorMode: _readString(json, 'editorMode') ?? 'normal',
      effortLevel: _readString(json, 'effortLevel'),
      fastMode: _readBool(json, 'fastMode') ?? false,
      hooks: _readStringMap(json, 'hooks'),
      mcpServers: _readMcpServers(json),
      model: _readString(json, 'model'),
      openRouterApiKey: _readString(json, 'openRouterApiKey'),
      outputStyle: _readString(json, 'outputStyle'),
      permissionMode: _readString(json, 'permissionMode') ?? 'default',
      privacyLevel: _readString(json, 'privacyLevel'),
      statusLinePrompt: _readString(json, 'statusLinePrompt'),
      telemetry: _readString(json, 'telemetry'),
      theme: _readString(json, 'theme') ?? 'dark',
    );
  }

  // advisor model name - optional
  final String? advisorModel;
  final List<String> alwaysAllowRules;
  final List<String> alwaysAskRules;
  final List<String> alwaysDenyRules;
  final String editorMode;
  final String? effortLevel;
  final bool fastMode;

  // hook configs keyed by event name
  final Map<String, String>? hooks;

  // mcp server configs - each entry is a map of server name -> config object
  final Map<String, Map<String, dynamic>>? mcpServers;
  final String? model;
  final String? openRouterApiKey;
  final String? outputStyle;
  final String permissionMode;
  final String? privacyLevel;
  final String? statusLinePrompt;
  final String? telemetry;
  final String theme;

  LocalSettings copyWith({
    Object? advisorModel = _sentinel,
    List<String>? alwaysAllowRules,
    List<String>? alwaysAskRules,
    List<String>? alwaysDenyRules,
    String? editorMode,
    Object? effortLevel = _sentinel,
    bool? fastMode,
    Object? hooks = _sentinel,
    Object? mcpServers = _sentinel,
    Object? model = _sentinel,
    Object? openRouterApiKey = _sentinel,
    Object? outputStyle = _sentinel,
    String? permissionMode,
    Object? privacyLevel = _sentinel,
    Object? statusLinePrompt = _sentinel,
    Object? telemetry = _sentinel,
    String? theme,
  }) {
    return LocalSettings(
      advisorModel: identical(advisorModel, _sentinel) ? this.advisorModel : advisorModel as String?,
      alwaysAllowRules: alwaysAllowRules ?? this.alwaysAllowRules,
      alwaysAskRules: alwaysAskRules ?? this.alwaysAskRules,
      alwaysDenyRules: alwaysDenyRules ?? this.alwaysDenyRules,
      editorMode: editorMode ?? this.editorMode,
      effortLevel: identical(effortLevel, _sentinel)
          ? this.effortLevel
          : effortLevel as String?,
      fastMode: fastMode ?? this.fastMode,
      hooks: identical(hooks, _sentinel) ? this.hooks : hooks as Map<String, String>?,
      mcpServers: identical(mcpServers, _sentinel) ? this.mcpServers : mcpServers as Map<String, Map<String, dynamic>>?,
      model: identical(model, _sentinel) ? this.model : model as String?,
      openRouterApiKey: identical(openRouterApiKey, _sentinel) ? this.openRouterApiKey : openRouterApiKey as String?,
      outputStyle: identical(outputStyle, _sentinel)
          ? this.outputStyle
          : outputStyle as String?,
      permissionMode: permissionMode ?? this.permissionMode,
      privacyLevel: identical(privacyLevel, _sentinel) ? this.privacyLevel : privacyLevel as String?,
      statusLinePrompt: identical(statusLinePrompt, _sentinel)
          ? this.statusLinePrompt
          : statusLinePrompt as String?,
      telemetry: identical(telemetry, _sentinel) ? this.telemetry : telemetry as String?,
      theme: theme ?? this.theme,
    );
  }

  // Merges this (base) with an override layer.
  // For nullable fields: override wins only if non-null.
  // For list fields: override wins if non-empty.
  // For non-nullable fields with defaults: override wins if different from its default.
  LocalSettings mergeWith(LocalSettings? override) {
    if (override == null) return this;

    return LocalSettings(
      advisorModel: override.advisorModel ?? advisorModel,
      alwaysAllowRules: override.alwaysAllowRules.isNotEmpty ? override.alwaysAllowRules : alwaysAllowRules,
      alwaysAskRules: override.alwaysAskRules.isNotEmpty ? override.alwaysAskRules : alwaysAskRules,
      alwaysDenyRules: override.alwaysDenyRules.isNotEmpty ? override.alwaysDenyRules : alwaysDenyRules,
      editorMode: override.editorMode != 'normal' ? override.editorMode : editorMode,
      effortLevel: override.effortLevel ?? effortLevel,
      fastMode: override.fastMode ? true : fastMode,
      hooks: override.hooks ?? hooks,
      mcpServers: override.mcpServers ?? mcpServers,
      model: override.model ?? model,
      openRouterApiKey: override.openRouterApiKey ?? openRouterApiKey,
      outputStyle: override.outputStyle ?? outputStyle,
      permissionMode: override.permissionMode != 'default' ? override.permissionMode : permissionMode,
      privacyLevel: override.privacyLevel ?? privacyLevel,
      statusLinePrompt: override.statusLinePrompt ?? statusLinePrompt,
      telemetry: override.telemetry ?? telemetry,
      theme: override.theme != 'dark' ? override.theme : theme,
    );
  }

  Map<String, dynamic> toJson() {
    return <String, dynamic>{
      'advisorModel': advisorModel,
      'alwaysAllowRules': alwaysAllowRules,
      'alwaysAskRules': alwaysAskRules,
      'alwaysDenyRules': alwaysDenyRules,
      'editorMode': editorMode,
      'effortLevel': effortLevel,
      'fastMode': fastMode,
      'hooks': hooks,
      'mcpServers': mcpServers,
      'model': model,
      'openRouterApiKey': openRouterApiKey,
      'outputStyle': outputStyle,
      'permissionMode': permissionMode,
      'privacyLevel': privacyLevel,
      'statusLinePrompt': statusLinePrompt,
      'telemetry': telemetry,
      'theme': theme,
    };
  }
}

class SessionState {
  SessionState({required this.workingDirectory, String? effortValue})
    : effortValue = effortValue,
      startedAt = DateTime.now().toUtc(),
      sessionId = _generateSessionId();

  String? effortValue;
  int commandsExecuted = 0;
  bool planModeEnabled = false;
  bool briefModeEnabled = false;
  bool bughunterMode = false;
  String? sessionColor;

  // set via /advisor
  String? advisorModel;

  // tag toggled via /tag command
  String? sessionTag;

  // name set via /rename
  String? sessionName;

  // extra dirs added via /add-dir
  final List<String> additionalDirectories = [];

  final DateTime startedAt;
  final String workingDirectory;
  final String sessionId;

  static String _generateSessionId() {
    final now = DateTime.now();
    final rnd = (now.millisecondsSinceEpoch % 1000000).toString().padLeft(6, '0');
    return 'sess_${now.millisecondsSinceEpoch}_$rnd';
  }

  String get planFilePath {
    return joinPath(getPlansDirectoryPath(), 'active-plan.md');
  }

  Future<String?> readPlan() async {
    final file = File(planFilePath);
    if (!await file.exists()) {
      return null;
    }

    return file.readAsString();
  }

  Future<void> writePlan(String content) async {
    final directory = Directory(getPlansDirectoryPath());
    await directory.create(recursive: true);
    await File(planFilePath).writeAsString(content);
  }
}

class SettingsStore {
  SettingsStore._({required this.path, required this.settings});

  static const _encoder = JsonEncoder.withIndent('  ');

  final String path;
  LocalSettings settings;

  static Future<SettingsStore> load() async {
    final path = getSettingsFilePath();
    final file = File(path);
    if (!await file.exists()) {
      final store = SettingsStore._(
        path: path,
        settings: const LocalSettings(),
      );
      await store.save();
      return store;
    }

    try {
      final raw = await file.readAsString();
      final decoded = jsonDecode(raw);
      if (decoded is Map<String, dynamic>) {
        return SettingsStore._(
          path: path,
          settings: LocalSettings.fromJson(decoded),
        );
      }
      if (decoded is Map) {
        return SettingsStore._(
          path: path,
          settings: LocalSettings.fromJson(
            decoded.map((key, value) => MapEntry(key.toString(), value)),
          ),
        );
      }
    } catch (_) {
      // Fall back to defaults if the file is unreadable.
    }

    final store = SettingsStore._(path: path, settings: const LocalSettings());
    await store.save();
    return store;
  }

  Future<void> save() async {
    final file = File(path);
    await file.parent.create(recursive: true);
    await file.writeAsString('${_encoder.convert(settings.toJson())}\n');
  }

  Future<void> update(
    LocalSettings Function(LocalSettings current) transform,
  ) async {
    settings = transform(settings);
    await save();
  }
}

const _sentinel = Object();

bool? _readBool(Map<String, dynamic> json, String key) {
  final value = json[key];
  if (value is bool) {
    return value;
  }

  return null;
}

String? _readString(Map<String, dynamic> json, String key) {
  final value = json[key];
  if (value is String && value.isNotEmpty) {
    return value;
  }

  return null;
}

List<String> _readStringList(Map<String, dynamic> json, String key) {
  final value = json[key];
  if (value is! List) {
    return const <String>[];
  }

  return value
      .whereType<String>()
      .where((item) => item.trim().isNotEmpty)
      .toList(growable: false);
}

Map<String, String>? _readStringMap(Map<String, dynamic> json, String key) {
  final value = json[key];
  if (value is! Map) {
    return null;
  }

  final result = <String, String>{};
  for (final entry in value.entries) {
    if (entry.key is String && entry.value is String) {
      result[entry.key as String] = entry.value as String;
    }
  }

  return result.isEmpty ? null : result;
}

Map<String, Map<String, dynamic>>? _readMcpServers(Map<String, dynamic> json) {
  final value = json['mcpServers'];
  if (value is! Map) {
    return null;
  }

  final result = <String, Map<String, dynamic>>{};

  for (final entry in value.entries) {
    if (entry.key is! String) continue;

    final serverCfg = entry.value;
    if (serverCfg is Map) {
      result[entry.key as String] = serverCfg.map(
        (k, v) => MapEntry(k.toString(), v),
      );
    }
  }

  return result.isEmpty ? null : result;
}