import { store } from "../store/store.js";
import * as lsm from "../lsm.js";

let lastBatch = null;

function resolveMxc(url, size, method) {
  const [server, id] = url.match(/^mxc:\/\/([^/]+)\/(.*)/).slice(1);
  if (size && method) {
    return `${lsm.get(
      "domain"
    )}/_matrix/media/r0/thumbnail/${server}/${id}?width=${size}&height=${size}&method=${method}`;
  } else {
    return `${lsm.get("domain")}/_matrix/media/r0/download/${server}/${id}`;
  }
}

function sync() {
  const url = new URL(`${lsm.get("domain")}/_matrix/client/r0/sync`);
  url.searchParams.append("access_token", lsm.get("access_token"));
  const filter = {
    room: {
      // pulling more from the timeline massively increases download size
      timeline: {
        limit: 5,
      },
      // members are not currently needed
      state: {
        lazy_load_members: true,
      },
    },
    presence: {
      // presence is not implemented, ignore it
      types: [],
    },
  };
  url.searchParams.append("filter", JSON.stringify(filter));
  url.searchParams.append("timeout", 20000);
  if (lastBatch) {
    url.searchParams.append("since", lastBatch);
  }
  return fetch(url.toString())
    .then((res) => res.json())
    .then((root) => {
      lastBatch = root.next_batch;
      return root;
    });
}

function manageSync(root) {
  try {
    let newEvents = false;

    // set up directs
    const directs = root.account_data.events.find((e) => e.type === "m.direct");
    if (directs) {
      Object.values(directs.content).forEach((ids) => {
        ids.forEach((id) => store.directs.add(id));
      });
    }

    // set up rooms
    Object.entries(root.rooms.join).forEach(([id, room]) => {
      if (!store.rooms.has(id)) {
        store.rooms.askAdd(id, room);
      }
      const timeline = store.rooms.get(id).value().timeline;
      if (room.timeline.events.length) newEvents = true;
      timeline.updateEvents(room.timeline.events);
    });

    // set up groups
    Promise.all(
      Object.keys(root.groups.join).map((id) => {
        if (!store.groups.has(id)) {
          return Promise.all(
            ["profile", "rooms"].map((path) => {
              const url = new URL(
                `${lsm.get("domain")}/_matrix/client/r0/groups/${id}/${path}`
              );
              url.searchParams.append("access_token", lsm.get("access_token"));
              return fetch(url.toString()).then((res) => res.json());
            })
          ).then(([profile, rooms]) => {
            rooms = rooms.chunk;
            let order = 999;
            let orderEvent = root.account_data.events.find(
              (e) => e.type === "im.vector.web.tag_ordering"
            );
            if (orderEvent) {
              if (orderEvent.content.tags.includes(id)) {
                order = orderEvent.content.tags.indexOf(id);
              }
            }
            const data = {
              name: profile.name,
              icon: resolveMxc(profile.avatar_url, 96, "crop"),
              order,
            };
            store.groups.askAdd(id, data);
            rooms.forEach((groupRoom) => {
              if (store.rooms.has(groupRoom.room_id)) {
                store.rooms.get(groupRoom.room_id).value().setGroup(id);
              }
            });
          });
        }
      })
    ).then(() => {
      store.rooms.sort();
    });
    if (newEvents) store.newEvents.broadcast("changeSelf");
  } catch (e) {
    console.error(root);
    throw e;
  }
}

function syncLoop() {
  return sync().then(manageSync).then(syncLoop);
}

[
  {
    id: "directs",
    name: "Directs",
    icon: "/static/directs.svg",
    order: -2,
  },
  {
    id: "channels",
    name: "Channels",
    icon: "/static/channels.svg",
    order: -1,
  },
].forEach((data) => store.groups.askAdd(data.id, data));

store.activeGroup.set(store.groups.get("directs").value());

syncLoop();