const estreePlugin = require("prettier/plugins/estree");

function hasSpecifierComments(node) {
  return (
    node.specifiers?.some((specifier) => specifier.comments?.length > 0) ??
    false
  );
}

function flattenImportLines(doc) {
  if (typeof doc === "string") {
    return doc;
  }

  if (Array.isArray(doc)) {
    return doc.map(flattenImportLines);
  }

  if (!doc || typeof doc !== "object") {
    return doc;
  }

  if (doc.type === "line") {
    return " ";
  }

  if ("contents" in doc) {
    return {
      ...doc,
      contents: flattenImportLines(doc.contents),
    };
  }

  if (doc.type === "fill" && "parts" in doc) {
    return {
      ...doc,
      parts: flattenImportLines(doc.parts),
    };
  }

  if (doc.type === "if-break") {
    return {
      ...doc,
      breakContents: flattenImportLines(doc.breakContents),
      flatContents: flattenImportLines(doc.flatContents),
    };
  }

  if (doc.type === "group" && "expandedStates" in doc) {
    return {
      ...doc,
      expandedStates: flattenImportLines(doc.expandedStates),
    };
  }

  return doc;
}

const estreePrinter = estreePlugin.printers.estree;

module.exports = {
  printers: {
    estree: {
      ...estreePrinter,
      print(path, options, print, args) {
        const printed = estreePrinter.print(path, options, print, args);
        const node = path.getNode();

        if (node?.type === "ImportDeclaration" && !hasSpecifierComments(node)) {
          return flattenImportLines(printed);
        }

        return printed;
      },
    },
  },
};