import { setKeyWiring, type ContactWiring, type ElcFile } from "./elc";

/** Assigns a row-major matrix to the supplied keys. The input order is preserved. */
export function wireMatrixKeys(
  elc: ElcFile,
  keyIds: string[],
  rowPins: string[],
  colPins: string[],
  diode?: "a-to-b" | "b-to-a",
): ElcFile {
  if (!rowPins.length || !colPins.length) throw new Error("rowPins and colPins are required");
  if (keyIds.length > rowPins.length * colPins.length)
    throw new Error("Matrix does not have enough row/column positions");
  let next = elc;
  keyIds.forEach((key, i) => {
    const wiring: ContactWiring = {
      key,
      detect: "contact",
      terminals: { a: rowPins[Math.floor(i / colPins.length)]!, b: colPins[i % colPins.length]! },
      ...(diode ? { diode } : {}),
    };
    // Keep unknown extension fields on an existing ELC entry, just like normal edits.
    next = setKeyWiring(next, wiring);
  });
  return next;
}