execute method

@override Future<ToolResult> execute(Map<String, dynamic> input)

Execute the tool with the given input.

Implementation

@override
Future<ToolResult> execute(Map<String, dynamic> input) async {
  final validation = validateInput(input);
  if (!validation.isValid) return ToolResult.error(validation.error!);

  final parsed = DiffApplyInput.fromJson(input);
  final file = File(parsed.filePath);

  if (!await file.exists()) {
    return ToolResult.error('File not found: ${parsed.filePath}');
  }

  try {
    final originalLines = await file.readAsLines();
    final patchedLines = _applyUnifiedDiff(originalLines, parsed.diffContent);
    final newContent = patchedLines.join('\n');
    await file.writeAsString(
      newContent.endsWith('\n') ? newContent : '$newContent\n',
    );

    final changed =
        (patchedLines.length - originalLines.length).abs() +
        _countChangedLines(originalLines, patchedLines);

    final out = DiffApplyOutput(
      success: true,
      linesChanged: changed,
      newContent: newContent,
    );
    return ToolResult.success(out.toString());
  } catch (e) {
    return ToolResult.error('Error applying diff: $e');
  }
}