import { Meteor } from 'meteor/meteor';
import { EJSON } from 'meteor/ejson';

import { API } from '../../../api/server';
import { logger } from '../lib/logger';
import { contextDefinitions, eventTypes } from '../../../models/server/models/FederationEvents';
import {
	FederationRoomEvents, FederationServers,
	Messages,
	Rooms,
	Subscriptions,
	Users,
} from '../../../models/server';
import { normalizers } from '../normalizers';
import { deleteRoom } from '../../../lib/server/functions';
import { Notifications } from '../../../notifications/server';
import { FileUpload } from '../../../file-upload';
import { getFederationDomain } from '../lib/getFederationDomain';
import { decryptIfNeeded } from '../lib/crypt';
import { isFederationEnabled } from '../lib/isFederationEnabled';
import { getUpload, requestEventsFromLatest } from '../handler';
import { notifyUsersOnMessage } from '../../../lib/server/lib/notifyUsersOnMessage';
import { sendAllNotifications } from '../../../lib/server/lib/sendNotificationsOnMessage';

API.v1.addRoute('federation.events.dispatch', { authRequired: false }, {
	async post() {
		if (!isFederationEnabled()) {
			return API.v1.failure('Federation not enabled');
		}

		//
		// Decrypt the payload if needed
		let payload;

		try {
			payload = decryptIfNeeded(this.request, this.bodyParams);
		} catch (err) {
			return API.v1.failure('Could not decrypt payload');
		}

		//
		// Convert from EJSON
		const { events } = EJSON.fromJSONValue(payload);

		logger.server.debug(`federation.events.dispatch => events=${ events.map((e) => JSON.stringify(e, null, 2)) }`);

		// Loop over received events
		for (const event of events) {
			/* eslint-disable no-await-in-loop */

			let eventResult;

			switch (event.type) {
				//
				// PING
				//
				case eventTypes.PING:
					eventResult = {
						success: true,
					};
					break;

				//
				// GENESIS
				//
				case eventTypes.GENESIS:
					switch (event.data.contextType) {
						case contextDefinitions.ROOM.type:
							eventResult = await FederationRoomEvents.addEvent(event.context, event);

							// If the event was successfully added, handle the event locally
							if (eventResult.success) {
								const { data: { room } } = event;

								// Check if room exists
								const persistedRoom = Rooms.findOne({ _id: room._id });

								if (persistedRoom) {
									// Update the federation
									Rooms.update({ _id: persistedRoom._id }, { $set: { federation: room.federation } });
								} else {
									// Denormalize room
									const denormalizedRoom = normalizers.denormalizeRoom(room);

									// Create the room
									Rooms.insert(denormalizedRoom);
								}
							}
							break;
					}
					break;

				//
				// ROOM_DELETE
				//
				case eventTypes.ROOM_DELETE:
					const { data: { roomId } } = event;

					// Check if room exists
					const persistedRoom = Rooms.findOne({ _id: roomId });

					if (persistedRoom) {
						// Delete the room
						deleteRoom(roomId);
					}

					// Remove all room events
					await FederationRoomEvents.removeRoomEvents(roomId);

					eventResult = {
						success: true,
					};

					break;

				//
				// ROOM_ADD_USER
				//
				case eventTypes.ROOM_ADD_USER:
					eventResult = await FederationRoomEvents.addEvent(event.context, event);

					// If the event was successfully added, handle the event locally
					if (eventResult.success) {
						const { data: { roomId, user, subscription, domainsAfterAdd } } = event;

						// Check if user exists
						const persistedUser = Users.findOne({ _id: user._id });

						if (persistedUser) {
							// Update the federation
							Users.update({ _id: persistedUser._id }, { $set: { federation: user.federation } });
						} else {
							// Denormalize user
							const denormalizedUser = normalizers.denormalizeUser(user);

							// Create the user
							Users.insert(denormalizedUser);
						}

						// Check if subscription exists
						const persistedSubscription = Subscriptions.findOne({ _id: subscription._id });

						if (persistedSubscription) {
							// Update the federation
							Subscriptions.update({ _id: persistedSubscription._id }, { $set: { federation: subscription.federation } });
						} else {
							// Denormalize subscription
							const denormalizedSubscription = normalizers.denormalizeSubscription(subscription);

							// Create the subscription
							Subscriptions.insert(denormalizedSubscription);
						}

						// Refresh the servers list
						FederationServers.refreshServers();

						// Update the room's federation property
						Rooms.update({ _id: roomId }, { $set: { 'federation.domains': domainsAfterAdd } });
					}
					break;

				//
				// ROOM_REMOVE_USER
				//
				case eventTypes.ROOM_REMOVE_USER:
					eventResult = await FederationRoomEvents.addEvent(event.context, event);

					// If the event was successfully added, handle the event locally
					if (eventResult.success) {
						const { data: { roomId, user, domainsAfterRemoval } } = event;

						// Remove the user's subscription
						Subscriptions.removeByRoomIdAndUserId(roomId, user._id);

						// Refresh the servers list
						FederationServers.refreshServers();

						// Update the room's federation property
						Rooms.update({ _id: roomId }, { $set: { 'federation.domains': domainsAfterRemoval } });
					}
					break;

				//
				// ROOM_MESSAGE
				//
				case eventTypes.ROOM_MESSAGE:
					eventResult = await FederationRoomEvents.addEvent(event.context, event);

					// If the event was successfully added, handle the event locally
					if (eventResult.success) {
						const { data: { message } } = event;

						// Check if message exists
						const persistedMessage = Messages.findOne({ _id: message._id });

						if (persistedMessage) {
							// Update the federation
							Messages.update({ _id: persistedMessage._id }, { $set: { federation: message.federation } });
						} else {
							// Load the room
							const room = Rooms.findOneById(message.rid);

							// Denormalize message
							const denormalizedMessage = normalizers.denormalizeMessage(message);

							// Is there a file?
							if (denormalizedMessage.file) {
								const fileStore = FileUpload.getStore('Uploads');

								const { federation: { origin } } = denormalizedMessage;

								const { upload, buffer } = getUpload(origin, denormalizedMessage.file._id);

								const oldUploadId = upload._id;

								// Normalize upload
								delete upload._id;
								upload.rid = denormalizedMessage.rid;
								upload.userId = denormalizedMessage.u._id;
								upload.federation = {
									_id: denormalizedMessage.file._id,
									origin,
								};

								Meteor.runAsUser(upload.userId, () => Meteor.wrapAsync(fileStore.insert.bind(fileStore))(upload, buffer));

								// Update the message's file
								denormalizedMessage.file._id = upload._id;

								// Update the message's attachments
								for (const attachment of denormalizedMessage.attachments) {
									attachment.title_link = attachment.title_link.replace(oldUploadId, upload._id);
									attachment.image_url = attachment.image_url.replace(oldUploadId, upload._id);
								}
							}

							// Create the message
							Messages.insert(denormalizedMessage);

							// Notify users
							notifyUsersOnMessage(denormalizedMessage, room);
							sendAllNotifications(denormalizedMessage, room);
						}
					}
					break;

				//
				// ROOM_EDIT_MESSAGE
				//
				case eventTypes.ROOM_EDIT_MESSAGE:
					eventResult = await FederationRoomEvents.addEvent(event.context, event);

					// If the event was successfully added, handle the event locally
					if (eventResult.success) {
						const { data: { message } } = event;

						// Check if message exists
						const persistedMessage = Messages.findOne({ _id: message._id });

						if (!persistedMessage) {
							eventResult.success = false;
							eventResult.reason = 'missingMessageToEdit';
						} else {
							// Update the message
							Messages.update({ _id: persistedMessage._id }, { $set: { msg: message.msg, federation: message.federation } });
						}
					}
					break;

				//
				// ROOM_DELETE_MESSAGE
				//
				case eventTypes.ROOM_DELETE_MESSAGE:
					eventResult = await FederationRoomEvents.addEvent(event.context, event);

					// If the event was successfully added, handle the event locally
					if (eventResult.success) {
						const { data: { roomId, messageId } } = event;

						// Remove the message
						Messages.removeById(messageId);

						// Notify the room
						Notifications.notifyRoom(roomId, 'deleteMessage', { _id: messageId });
					}
					break;

				//
				// ROOM_SET_MESSAGE_REACTION
				//
				case eventTypes.ROOM_SET_MESSAGE_REACTION:
					eventResult = await FederationRoomEvents.addEvent(event.context, event);

					// If the event was successfully added, handle the event locally
					if (eventResult.success) {
						const { data: { messageId, username, reaction } } = event;

						// Get persisted message
						const persistedMessage = Messages.findOne({ _id: messageId });

						// Make sure reactions exist
						persistedMessage.reactions = persistedMessage.reactions || {};

						let reactionObj = persistedMessage.reactions[reaction];

						// If there are no reactions of that type, add it
						if (!reactionObj) {
							reactionObj = {
								usernames: [username],
							};
						} else {
							// Otherwise, add the username
							reactionObj.usernames.push(username);
							reactionObj.usernames = [...new Set(reactionObj.usernames)];
						}

						// Update the property
						Messages.update({ _id: messageId }, { $set: { [`reactions.${ reaction }`]: reactionObj } });
					}
					break;

				//
				// ROOM_UNSET_MESSAGE_REACTION
				//
				case eventTypes.ROOM_UNSET_MESSAGE_REACTION:
					eventResult = await FederationRoomEvents.addEvent(event.context, event);

					// If the event was successfully added, handle the event locally
					if (eventResult.success) {
						const { data: { messageId, username, reaction } } = event;

						// Get persisted message
						const persistedMessage = Messages.findOne({ _id: messageId });

						// Make sure reactions exist
						persistedMessage.reactions = persistedMessage.reactions || {};

						// If there are no reactions of that type, ignore
						if (!persistedMessage.reactions[reaction]) {
							continue;
						}

						const reactionObj = persistedMessage.reactions[reaction];

						// Get the username index on the list
						const usernameIdx = reactionObj.usernames.indexOf(username);

						// If the index is not found, ignore
						if (usernameIdx === -1) {
							continue;
						}

						// Remove the username from the given reaction
						reactionObj.usernames.splice(usernameIdx, 1);

						// If there are no more users for that reaction, remove the property
						if (reactionObj.usernames.length === 0) {
							Messages.update({ _id: messageId }, { $unset: { [`reactions.${ reaction }`]: 1 } });
						} else {
							// Otherwise, update the property
							Messages.update({ _id: messageId }, { $set: { [`reactions.${ reaction }`]: reactionObj } });
						}
					}
					break;

				//
				// ROOM_MUTE_USER
				//
				case eventTypes.ROOM_MUTE_USER:
					eventResult = await FederationRoomEvents.addEvent(event.context, event);

					// If the event was successfully added, handle the event locally
					if (eventResult.success) {
						const { data: { roomId, user } } = event;

						// Denormalize user
						const denormalizedUser = normalizers.denormalizeUser(user);

						// Mute user
						Rooms.muteUsernameByRoomId(roomId, denormalizedUser.username);
					}
					break;

				//
				// ROOM_UNMUTE_USER
				//
				case eventTypes.ROOM_UNMUTE_USER:
					eventResult = await FederationRoomEvents.addEvent(event.context, event);

					// If the event was successfully added, handle the event locally
					if (eventResult.success) {
						const { data: { roomId, user } } = event;

						// Denormalize user
						const denormalizedUser = normalizers.denormalizeUser(user);

						// Mute user
						Rooms.unmuteUsernameByRoomId(roomId, denormalizedUser.username);
					}
					break;

				//
				// Could not find event
				//
				default:
					continue;
			}

			// If there was an error handling the event, take action
			if (!eventResult.success) {
				logger.server.debug(`federation.events.dispatch => Event has missing parents -> event=${ JSON.stringify(event, null, 2) }`);

				requestEventsFromLatest(event.origin, getFederationDomain(), contextDefinitions.defineType(event), event.context, eventResult.latestEventIds);

				// And stop handling the events
				break;
			}

			/* eslint-enable no-await-in-loop */
		}

		// Respond
		return API.v1.success();
	},
});