import axios from 'axios';
import { activeChannel, channelsList, events } from './store';

export const apiServer = axios.create({
  baseURL: '/api/',
});

export async function boot() {
  return apiServer.get('/boot');
}

export async function logIn(username, password) {
  const data = {
    name: username,
    password,
  };
  return apiServer.post('/auth/login', data);
}

export async function logOut() {
  return apiServer.post('/auth/logout', {});
}

export async function listChannels() {
  return apiServer.get('/channels');
}

export async function createChannel(name) {
  return apiServer.post('/channels', { name });
}

export async function postToChannel(channelId, message) {
  return apiServer.post(`/channels/${channelId}`, { message });
}

export async function deleteMessage(messageId) {
  // TODO
}

export function subscribeToEvents() {
  const evtSource = new EventSource("/api/events");
  events.update(() => []);
  // TODO: this should process all incoming events and store them.
  // TODO: eventually we'll need to handle expiring old info, so as not to use
  //       infinite browser memory.
  /*
   * Known message types as of now:
   * - created: a channel is created.
   *   - action: ignore.
   * - message: a message is created.
   *   - action: display message in channel.
   * - message_deleted: a message is deleted.
   *   - action: replace message with <...>.
   * - deleted: a channel is deleted.
   *   - action: remove channel from sidebar.
  */
  evtSource.onmessage = (evt) => {
    const data = JSON.parse(evt.data);

    switch (data.type) {
      case 'created':
        break;
      case 'message':
        events.update((value) => {
          const eventList = [...value, data];
          eventList.sort((a, b) => a.at - b.at);
          return eventList;
        });
        break;
      case 'message_deleted':
        events.update((value) => {
          const eventList = value.map((el) => {
            if (el.message?.id === data.message) {
              el.message.body = '&laquo;&hellip;&raquo;';
              return el
            } else {
              return el;
            }
          });
          return eventList;
        });
        break;
      case 'deleted':
        activeChannel.update((value) => {
          if (value?.id === data.channel) {
            return null;
          }
          return value;
        });
        channelsList.update((value) => {
          const channelIndex = value.map((e) => e.id).indexOf(data.channel);
          if (channelIndex !== -1) {
            value.splice(channelIndex, 1);
          }
          return value;
        });
        break;
      default:
        break;
    }
  }
}