import { Reducer } from 'react';
import Setting from '../models/Setting';
import { ApplicationPlatform, ApplicationType } from '../types';
import shim from '../shim';
import { _ } from '../locale';
import eventManager, { EventName } from '../eventManager';
import { reg } from '../registry';
import SyncTargetRegistry from '../SyncTargetRegistry';
import Logger from '@joplin/utils/Logger';
import NavService from './NavService';

const logger = Logger.create('joplinCloudUtils');

type ActionType = 'LINK_USED' | 'COMPLETED' | 'ERROR';
type Action = {
	type: ActionType;
	payload?: string;
};

type DefaultState = {
	className: 'text' | 'bold';
	message: ()=> string;
	next: ActionType;
	active: ActionType | 'INITIAL';
	errorMessage?: string;
};

export const defaultState: DefaultState = {
	className: 'text',
	message: ()=> _('Waiting for authorisation...'),
	next: 'LINK_USED',
	active: 'INITIAL',
};

export const reducer: Reducer<DefaultState, Action> = (state: DefaultState, action: Action) => {
	switch (action.type) {
	case 'LINK_USED': {
		return {
			className: 'text',
			message: () => _('If you have already authorised, please wait for the application to sync to Joplin Cloud.'),
			next: 'COMPLETED',
			active: 'LINK_USED',
		};
	}
	case 'COMPLETED': {
		return {
			className: 'bold',
			message: () => _('You are logged in into Joplin Cloud, you can leave this screen now.'),
			active: 'COMPLETED',
			next: 'COMPLETED',
		};
	}
	case 'ERROR': {
		return {
			className: 'text',
			message: () => _('You were unable to connect to Joplin Cloud. Please check your credentials and try again. Error:'),
			active: 'ERROR',
			next: 'COMPLETED',
			errorMessage: action.payload,
		};
	}
	default: {
		return state;
	}
	}
};

export const getApplicationInformation = async () => {
	const platformName = await shim.platformName();
	switch (platformName) {
	case 'ios':
		return { type: ApplicationType.Mobile, platform: ApplicationPlatform.Ios };
	case 'android':
		return { type: ApplicationType.Mobile, platform: ApplicationPlatform.Android };
	case 'web':
		return { type: ApplicationType.Mobile, platform: ApplicationPlatform.Web };
	case 'darwin':
		return { type: ApplicationType.Desktop, platform: ApplicationPlatform.MacOs };
	case 'win32':
		return { type: ApplicationType.Desktop, platform: ApplicationPlatform.Windows };
	case 'linux':
		return { type: ApplicationType.Desktop, platform: ApplicationPlatform.Linux };
	default:
		return { type: ApplicationType.Unknown, platform: ApplicationPlatform.Unknown };
	}
};

export const generateApplicationConfirmUrl = async (confirmUrl: string) => {
	const applicationInfo = await getApplicationInformation();
	const searchParams = new URLSearchParams();
	searchParams.append('platform', applicationInfo.platform.toString());
	searchParams.append('type', applicationInfo.type.toString());
	searchParams.append('version', shim.appVersion());

	return `${confirmUrl}?${searchParams.toString()}`;
};

export const saveApplicationAuthId = async (applicationAuthId: string) => {
	Setting.setValue('sync.10.pendingAuthId', applicationAuthId);
	await Setting.saveAll();
};

export const openLoginScreen = () => {
	const syncTargetId = 10;
	const syncTarget = reg.syncTarget(syncTargetId);
	return NavService.go(syncTarget.authRouteName());
};

// We have isWaitingResponse inside the function to avoid any state from lingering
// after an error occurs. E.g.: if the function would throw an error while isWaitingResponse
// was set to true the next time we call the function the value would still be true.
// The closure function prevents that.
export const checkIfLoginWasSuccessful = async (applicationsUrl: string) => {
	let isWaitingResponse = false;
	const performLoginRequest = async () => {
		if (isWaitingResponse) return undefined;
		isWaitingResponse = true;

		const response = await fetch(applicationsUrl, {
			headers: {
				'X-JOPLIN-CUSTOM-API-KEY': Setting.value('sync.10.apiKey'),
			},
		});
		const jsonBody = await response.json();

		if (!response.ok || jsonBody.status !== 'finished') {
			isWaitingResponse = false;
			return undefined;
		}

		Setting.setValue('sync.10.username', jsonBody.id);
		Setting.setValue('sync.10.password', jsonBody.password);
		Setting.setValue('sync.target', SyncTargetRegistry.nameToId('joplinCloud'));
		Setting.setValue('sync.10.pendingAuthId', '');

		const fileApi = await reg.syncTarget().fileApi();
		await fileApi.driver().api().loadSession();
		eventManager.emit(EventName.SessionEstablished);

		return { success: true };
	};

	return performLoginRequest();
};

// If the app was killed during the OAuth flow (common on Android), the
// pending auth ID is still saved. On startup we check whether the server
// has already confirmed the authorisation and, if so, save the credentials.
export const completePendingAuthentication = async () => {
	const pendingAuthId = Setting.value('sync.10.pendingAuthId');
	if (!pendingAuthId) return;

	const apiBaseUrl = Setting.value('sync.10.path');
	const applicationsUrl = `${apiBaseUrl}/api/application_auth/${pendingAuthId}`;

	try {
		const result = await checkIfLoginWasSuccessful(applicationsUrl);
		if (result && result.success) {
			logger.info('Completed pending Joplin Cloud authentication');
		}
	} catch (error) {
		logger.error('Could not complete pending authentication:', error);
	} finally {
		Setting.setValue('sync.10.pendingAuthId', '');
	}
};