import type { DetectedField } from "./detect";
import { isAnyCredentialForm } from "./detect";

export interface AutofillInteractionTargets {
  usernameEl: HTMLInputElement | null;
  passwordEl: HTMLInputElement | null;
  /** Separate email field, present only when the form has both a username and a distinct email field. */
  emailEl: HTMLInputElement | null;
  shouldOpen: boolean;
}

/**
 * Explicit icon clicks should still work when passive heuristics are too
 * cautious. Prefer the real detected fields when present, but allow the click
 * path to open Peach even if the current page only exposes a partial form.
 */
export function resolveAutofillInteractionTargets(
  anchorField: HTMLInputElement,
  fields: DetectedField[],
  explicitSummon = false
): AutofillInteractionTargets {
  const usernameField = fields.find((f) => f.type === "username");
  const emailField = fields.find((f) => f.type === "email");
  const pwField = fields.find((f) => f.type === "password");
  const anchorType = anchorField.type.toLowerCase();
  const fallbackType = anchorType === "password" ? "password" : "username";

  // When both a username and a dedicated email field exist, track them separately.
  // When only an email field exists (email-first login / email-as-identifier), treat it
  // as usernameEl so callers fill it with entry.username; emailEl stays null.
  const hasDistinctUsername = !!usernameField;
  const identityEl = usernameField?.el ?? emailField?.el ?? null;

  return {
    usernameEl: identityEl ?? (explicitSummon && fallbackType === "username" ? anchorField : null),
    passwordEl: pwField?.el ?? (explicitSummon && fallbackType === "password" ? anchorField : null),
    emailEl: hasDistinctUsername ? (emailField?.el ?? null) : null,
    shouldOpen: explicitSummon || isAnyCredentialForm(fields),
  };
}