mAAdhaTTah/brookjs

import {
  State,
  Action,
  ConfiguringState,
  ConfiguredState,
  unreachable,
} from './types';
import { defaultSteps } from './constants';

const applyDefaults = (
  config: ConfiguringState['config'],
): ConfiguredState['config'] =>
  (Object.keys(config) as (keyof typeof config)[]).reduce<
    ConfiguredState['config']
  >(
    (acc, key) => ({
      ...acc,
      [key]: config[key] ?? acc[key],
    }),
    defaultSteps,
  );

const reducer = (state: State, action: Action): State => {
  switch (action.type) {
    case 'INPUT':
      // Only handle input on configure step.
      if (state.step !== 'configure') {
        return state;
      }
      return {
        ...state,
        config: {
          ...state.config,
          [state.configuring]: action.payload.value,
        },
      };
    case 'SUBMIT':
      switch (state.step) {
        case 'configure':
          switch (state.configuring) {
            case 'version':
              return {
                ...state,
                configuring: 'description',
              };
            case 'description':
              return {
                ...state,
                configuring: 'dir',
              };
            case 'dir':
              return {
                ...state,
                configuring: 'license',
              };
            case 'license':
              return {
                ...state,
                step: 'confirm',
                configuring: null,
                config: applyDefaults(state.config),
              };
            default:
              return unreachable(state.configuring);
          }
        case 'confirm':
        case 'creating':
        case 'complete':
        case 'cancelled':
        case 'error':
          // SUBMIT is only relevant to the configure step.
          // This code won't ever actually run.
          return state;
        default:
          return unreachable(state);
      }
    case 'CONFIRM':
      // CONFIRM should only be emitted from confirm step.
      if (state.step !== 'confirm') {
        return state;
      }

      if (action.payload.value) {
        return {
          ...state,
          step: 'creating',
        };
      } else {
        return {
          ...state,
          step: 'cancelled',
        };
      }
    case 'LOG':
      return {
        ...state,
        logs: [...state.logs, action.payload],
      };
    case 'CREATED':
      // CREATED should only be emitted from creating step
      if (state.step !== 'creating') {
        return state;
      }

      return {
        ...state,
        step: 'complete',
        result: action.payload.result,
      };
    case 'FAILED':
      // CREATED should only be emitted from creating step
      if (state.step !== 'creating') {
        return state;
      }

      return {
        ...state,
        step: 'error',
        error: action.payload.error,
      };
    default:
      return state;
  }
};

export default reducer;