packages/frontend/lib/features/agent/tools/preview/find_widget_tool.dart

import 'dart:convert';

import 'package:schemantic/schemantic.dart';

import '../../../shared/logic/app_event_bus.dart';
import '../../models/agent_tool_event.dart';
import '../../models/agent_tool_id.dart';
import '../base/agent_tool.dart';
import '../tool_schemas.dart';

/// Finds widgets in the running preview matching query text or type.
class FindWidgetTool extends AgentTool<FindWidgetInput, FindWidgetOutput> {
  const FindWidgetTool({
    required this.commandBus,
  });

  final AppCommandBus commandBus;

  @override
  AgentToolId get toolId => AgentToolId.findWidget;

  @override
  String get description =>
      'Search for widgets in the running app preview by matching visible text or widget type. '
      'Returns matching widgets with their node IDs to allow interaction (tap, enter text, scroll, details).';

  @override
  SchemanticType<FindWidgetInput> get inputSchema => FindWidgetInput.$schema;

  @override
  SchemanticType<FindWidgetOutput> get outputSchema => FindWidgetOutput.$schema;

  Future<String?> _invokeExtension(String method, Map<String, String> args) {
    return commandBus.dispatchAsync(InvokePreviewExtensionCommand(
      method: method,
      args: args,
    ));
  }

  @override
  Future<FindWidgetOutput> run(FindWidgetInput input) async {
    final state = await commandBus.dispatchAsync(RequestPreviewStateCommand());
    if (!state.hasActiveRuntime) {
      return FindWidgetOutput(
        success: false,
        error: 'No app preview is running. Use controlApp to start the preview first.',
      );
    }

    try {
      final responseStr = await _invokeExtension(
        'ext.vibepad.findWidgets',
        {
          if (input.text != null) 'text': input.text!,
          if (input.type != null) 'type': input.type!,
          if (input.rootNodeId != null) 'rootNodeId': input.rootNodeId!,
        },
      );

      if (responseStr == null || responseStr.isEmpty) {
        return FindWidgetOutput(
          success: false,
          error: 'Could not find widgets matching the query. No response from the running app.',
        );
      }

      final Map<String, dynamic> decoded = jsonDecode(responseStr) as Map<String, dynamic>;
      final success = decoded['success'] as bool? ?? false;
      if (!success) {
        return FindWidgetOutput(
          success: false,
          error: decoded['error'] as String? ?? 'Failed to search widgets.',
        );
      }

      final rawMatches = decoded['matches'] as List<dynamic>? ?? const [];
      final matches = rawMatches.map((m) {
        final matchMap = m as Map<String, dynamic>;
        return FindWidgetMatch(
          id: matchMap['id'] as String,
          widget: matchMap['widget'] as String,
        );
      }).toList();

      return FindWidgetOutput(
        success: true,
        matches: matches,
      );
    } catch (e) {
      return FindWidgetOutput(
        success: false,
        error: 'Failed to search widgets: $e',
      );
    }
  }

  String _truncate(String val, int maxLength) {
    if (val.length <= maxLength) {
      return val;
    }
    return '${val.substring(0, maxLength)}...';
  }

  String _formatQuery(FindWidgetInput input) {
    final queries = [
      if (input.type != null) 'type: ${input.type}',
      if (input.text != null) 'text: "${_truncate(input.text!, 20)}"',
    ].join(', ');
    return queries.isEmpty ? 'any' : queries;
  }

  @override
  AgentToolEvent mapStartToToolEvent(FindWidgetInput input) {
    return createToolEvent(
      status: ToolStatus.running,
      summary: 'Finding widgets (${_formatQuery(input)})',
    );
  }

  @override
  AgentToolEvent mapToToolEvent(
    FindWidgetInput input,
    FindWidgetOutput output,
  ) {
    final count = output.matches?.length ?? 0;
    final matchWord = count == 1 ? 'widget' : 'widgets';
    final queryStr = _formatQuery(input);
    return createToolEvent(
      status: output.success ? ToolStatus.success : ToolStatus.error,
      summary: output.success ? 'Found $count $matchWord ($queryStr)' : 'Failed to find widgets ($queryStr)',
      errorMessage: output.error,
    );
  }
}