import { ElementUIComponent, ElementUIComponentSize } from './component';

export type FormItemLabelPosition = 'left' | 'right' | 'top';

export interface ValidateCallback {
  /**
   * The callback to tell the validation result
   *
   * @param isValid Whether the form is valid
   * @param invalidFields fields that fail validation
   */
  (isValid: boolean, invalidFields: object): void;
}

export interface ValidateFieldCallback {
  /**
   * The callback to tell the field validation result
   *
   * @param errorMessage The error message. It will be empty if there is no error
   */
  (errorMessage: string): void;
}

/** Form Component */
export declare class ElForm extends ElementUIComponent {
  /** Data of form component */
  model: object;

  /** Validation rules of form */
  rules: object;

  /** Whether the form is inline */
  inline: boolean;

  /** Whether the form is disabled */
  disabled: boolean;

  /** Position of label */
  labelPosition: FormItemLabelPosition;

  /** Width of label, and all form items will inherit from Form */
  labelWidth: string;

  /** Suffix of the label */
  labelSuffix: string;

  /** Whether to show the error message */
  showMessage: boolean;

  /** Whether to display the error message inline with the form item */
  inlineMessage: boolean;

  /** Whether to display an icon indicating the validation result */
  statusIcon: boolean;

  /** Whether to trigger validation when the `rules` prop is changed */
  validateOnRuleChange: boolean;

  /** Controls the size of components in this form */
  size: ElementUIComponentSize;

  /**
   * Validate the whole form
   *
   * @param callback A callback to tell the validation result
   */
  validate(callback: ValidateCallback): void;
  validate(): Promise<boolean>;
  /**
   * Validate certain form items
   *
   * @param props The property of `model` or array of prop which is going to validate
   * @param callback A callback to tell the field validation result
   */
  validateField(props: string | string[], callback: ValidateFieldCallback): void;

  /** reset all the fields and remove validation result */
  resetFields(): void;

  /** clear validation message for certain fields */
  clearValidate(props?: string | string[]): void;
}