import { SchemaBase } from './dsl.js';
import type { DtoField, DtoMessage, DtoArrayField, DtoObjectField } from './dto.js';
import type { RefSchema } from './ref.js';
import type { ControllerMethodSchema } from './controller.js';

// Page actions: what a user can do ON a page (e.g. submit, approve, reject).
// Distinguished from the cross-domain Action (journey): page actions live in
// the page skeleton (PageDef.actions / PageSchema.pageDef) and describe the
// page's own operation surface; journey actions describe what happens along a
// business line (page / controller / third / db / task). Subclasses use
// `type` as the discriminator.

/** An action a user can perform on a page (e.g. submit, approve, reject).
 *  Subclasses use `type` as the discriminator. */
export interface PageActionSchema extends SchemaBase {
  type: string;
}

export function definePageAction(name: string, description?: string): PageActionSchema {
  return { name, description, type: 'gesture' };
}

/** Parameter data source for a call argument. */
export type DataRef =
  | { type: 'route'; key: string }
  | { type: 'data';  key: string }
  | { type: 'value'; value: unknown };

/** Create a route-parameter reference. */
export function route(key: string): DataRef {
  return { type: 'route', key };
}

/** Create a page-data reference. */
export function data(key: string): DataRef {
  return { type: 'data', key };
}

export interface CallAction extends PageActionSchema {
  type: 'call';
  func: ControllerMethodSchema;
  args?: Record<string, DtoField | DtoMessage | DtoArrayField | DtoObjectField | RefSchema | string>;
}

export function call(func: ControllerMethodSchema, args?: Record<string, DtoField | DtoMessage | DtoArrayField | DtoObjectField | RefSchema | string>): CallAction {
  return { name: func.name, type: 'call', func, args };
}

/** Assign a call's result to a page data field.
 *  React: setState({ [field]: await ... }). Mini-program: this.setData({ [field]: ... }). */
export interface SetDataAction extends PageActionSchema {
  type: 'setData';
  call: CallAction;
  field: DtoField;
}

export function setData(call: CallAction, field: DtoField): SetDataAction {
  return { name: 'setData', type: 'setData', call, field };
}