import { FileApi } from '../../file-api';
// import Logger from '../../Logger';
import Setting from '../../models/Setting';
import uuid from '../../uuid';
import { MasterKeyEntity } from '../database/types';
const ArrayUtils = require('../../ArrayUtils');

// const logger = Logger.create('SyncTargetInfoHandler');

export interface SyncTargetInfo {
	version: number;
	e2ee: boolean;
	updatedTime: number;
	masterKeys: Record<string, MasterKeyEntity>;
	activeMasterKeyId: string;
}

function serializeSyncTargetInfo(info: SyncTargetInfo): string {
	return JSON.stringify(info, null, '\t');
}

function unserializeSyncTargetInfo(info: string): SyncTargetInfo {
	return JSON.parse(info);
}

// export function setLocalSyncTargetInfoProp(key:string, value:any):void {
// 	const info = localSyncTargetInfo();
// 	if (!info) throw new Error('Local sync target info has not been set!');
// 	if (!(key in info)) throw new Error('Invalid sync target info key: ' + key);

// 	setLocalSyncTargetInfo({
// 		...info,
// 		[key]: value,
// 	});
// }

// export function localSyncTargetInfoProp(key:string):any {
// 	const info = localSyncTargetInfo();
// 	if (!info) throw new Error('Local sync target info has not been set!');
// 	if (!(key in info)) throw new Error('Invalid sync target info key: ' + key);
// 	return (info as any)[key];
// }

function defaultSyncTargetInfo(): SyncTargetInfo {
	return {
		e2ee: false,
		activeMasterKeyId: '',
		masterKeys: {},
		version: 0,
		updatedTime: 0,
	};
}

export function setLocalSyncTargetInfo(info: SyncTargetInfo) {
	Setting.setValue('sync.info', serializeSyncTargetInfo(info));
}

export function localSyncTargetInfo(mustExist: boolean = false): SyncTargetInfo | null {
	const info = Setting.value('sync.info');
	if (mustExist && !info) throw new Error('Sync info is not set');
	return info ? unserializeSyncTargetInfo(info) : defaultSyncTargetInfo();
}

function validateInfo(info: SyncTargetInfo) {
	if (!info.version) throw new Error('Missing "version" field in info.json');
}

export function syncTargetInfoEquals(info1: SyncTargetInfo, info2: SyncTargetInfo): boolean {
	if (info1.e2ee !== info2.e2ee) return false;
	if (info1.version !== info2.version) return false;

	const mks1 = info1.masterKeys || {};
	const mks2 = info2.masterKeys || {};

	if (Object.keys(mks1).length !== Object.keys(mks2).length) return false;

	for (const [id, mk1] of Object.entries(mks1)) {
		const mk2 = mks2[id];
		if (!mk2) return false;

		if (mk1.updated_time !== mk2.updated_time) return false;
	}

	return true;
}

export function mergeSyncTargetInfos(info1: SyncTargetInfo, info2: SyncTargetInfo): SyncTargetInfo {
	const baseInfo = info1.updatedTime > info2.updatedTime ? info1 : info2;

	const newInfo: SyncTargetInfo = { ...baseInfo };

	const masterKeyIds = ArrayUtils.unique(
		Object.keys(info1.masterKeys ? info1.masterKeys : {}).concat(
			Object.keys(info2.masterKeys ? info2.masterKeys : {})
		)
	);

	const mergedMasterKeys: Record<string, MasterKeyEntity> = {};

	for (const id of masterKeyIds) {
		const mk1 = info1.masterKeys[id] || { updated_time: 0 };
		const mk2 = info2.masterKeys[id] || { updated_time: 0 };
		mergedMasterKeys[id] = mk1.updated_time > mk2.updated_time ? mk1 : mk2;
	}

	newInfo.masterKeys = mergedMasterKeys;
	return newInfo;
}

export async function remoteSyncTargetInfo(api: FileApi): Promise<SyncTargetInfo> {
	const syncTargetInfoText = await api.get('info.json');

	const defaultFields: SyncTargetInfo = {
		version: 0,
		e2ee: false,
		updatedTime: 0,
		masterKeys: {},
		activeMasterKeyId: '',
	};

	// Returns version 0 if the sync target is empty
	let output: SyncTargetInfo = defaultFields;

	if (syncTargetInfoText) {
		output = unserializeSyncTargetInfo(syncTargetInfoText);
		validateInfo(output);
	} else {
		const oldVersion = await api.get('.sync/version.txt');
		if (oldVersion) output = { ...defaultFields, version: 1 };
	}

	return output;
}

export async function setRemoteSyncTargetInfo(api: FileApi, info: SyncTargetInfo) {
	await api.put('info.json', serializeSyncTargetInfo(info));
}

// -----------------------------------------------------------------------
// Utility functions to manipulate the SyncTargetInfo data
// -----------------------------------------------------------------------

export function activeMasterKey(info: SyncTargetInfo): MasterKeyEntity {
	if (!info.activeMasterKeyId) return null;

	// Sanity check - but shouldn't happen because the key is saved at the same
	// time as the active master key is set.
	if (!info.masterKeys[info.activeMasterKeyId]) throw new Error('Active master key is not present in info.json');

	return info.masterKeys[info.activeMasterKeyId];
}

export function activeMasterKeyId() {
	return localSyncTargetInfo().activeMasterKeyId;
}

export function setActiveMasterKeyId(id: string) {
	const info = localSyncTargetInfo();
	if (info.activeMasterKeyId === id) return;

	setLocalSyncTargetInfo({
		...localSyncTargetInfo(),
		activeMasterKeyId: id,
		updatedTime: Date.now(),
	});
}

export function setEncryptionEnabled(enable: boolean = true, activeMasterKeyId: string = null) {
	const info = localSyncTargetInfo(false);
	if (info.e2ee === enable) return;

	const newInfo = {
		...info,
		e2ee: enable,
		updatedTime: Date.now(),
	};

	if (activeMasterKeyId !== null) newInfo.activeMasterKeyId = activeMasterKeyId;

	setLocalSyncTargetInfo(newInfo);
}

export function encryptionEnabled() {
	const info = localSyncTargetInfo(false);
	return info.e2ee;
}

export function encryptionDisabled() {
	return !encryptionEnabled();
}

export function masterKeyById(id: string): MasterKeyEntity {
	return localSyncTargetInfo().masterKeys[id];
}

export function saveMasterKey(mk: MasterKeyEntity): MasterKeyEntity {
	const info = localSyncTargetInfo();

	const id = mk.id ? mk.id : uuid.create();

	const newMasterKey = {
		id,
		...info.masterKeys[id],
		...mk,
	};

	setLocalSyncTargetInfo({
		...info,
		masterKeys: {
			...info.masterKeys,
			[newMasterKey.id]: newMasterKey,
		},
		updatedTime: Date.now(),
	});

	return newMasterKey;
}

export function masterKeyAll(): MasterKeyEntity[] {
	const masterKeys = localSyncTargetInfo().masterKeys;
	return Object.keys(masterKeys).map(id => masterKeys[id]);
}