// ------- Input -------
import { objectType } from "nexus";

// Original comment
export const Toto = objectType({
    name: "Query",
    definition(t) {
        t.string("hello");
    }
});

// ------- Expected output -------
import { objectType } from "nexus";
//Improved comment
export const Toto = objectType({
    name: "Query",
    definition(t) {
        t.string("hello");
    }
});

// ------- Actual output -------
import { objectType } from "nexus";
//Improved comment
// Original comment
export const Toto = objectType({
    name: "Query",
    definition(t) {
        t.string("hello");
    }
});

// ------- Implementation -------
const transformFactoryStack = (context: ts.TransformationContext) => (
  rootNode: ts.SourceFile
): ts.SourceFile => {
  const visit = (node: ts.Node) => {
    node = ts.visitEachChild(node, visit, context);

    if (ts.isVariableStatement(node)) {
      let sourceFileText = node.getSourceFile().text;
      const existingComments = ts.getLeadingCommentRanges(
        sourceFileText,
        node.pos
      );

      if (existingComments) {
        // Log existing comments just for fun
        for (const comment of existingComments) {
          console.log({
            existingComment: sourceFileText.substring(comment.pos, comment.end)
          });
        }

        ts.setTextRange(node, { pos: node.getStart(), end: node.getEnd() });
        ts.setSyntheticLeadingComments(node, [
          {
            pos: -1,
            end: -1,
            hasTrailingNewLine: false,
            text: "Improved comment",
            kind: ts.SyntaxKind.SingleLineCommentTrivia
          }
        ]);
      }
    }

    return node;
  };

  return ts.visitNode(rootNode, visit);
};