const request = require('request-promise-native');
module.exports = Self => {
    Self.remoteMethodCtx('sendMessage', {
        description: 'Send a RocketChat message',
        accessType: 'WRITE',
        accepts: [{
            arg: 'to',
            type: 'String',
            required: true,
            description: 'user (@) or channel (#) to send the message'
        }, {
            arg: 'message',
            type: 'String',
            required: true,
            description: 'The message'
        }],
        returns: {
            type: 'Object',
            root: true
        },
        http: {
            path: `/sendMessage`,
            verb: 'POST'
        }
    });

    Self.sendMessage = async(ctx, to, message) => {
        const models = Self.app.models;
        const accessToken = ctx.req.accessToken;
        const sender = await models.Account.findById(accessToken.userId);
        const recipient = to.replace('@', '');

        if (sender.name != recipient)
            return sendMessage(to, `@${sender.name}: ${message}`);
    };

    async function sendMessage(name, message) {
        const models = Self.app.models;
        const chatConfig = await models.ChatConfig.findOne();

        if (!Self.token)
            Self.token = await login();

        const uri = `${chatConfig.uri}/chat.postMessage`;
        return send(uri, {
            'channel': name,
            'text': message
        }).catch(async error => {
            if (error.statusCode === 401 && !Self.loginAttempted) {
                Self.token = await login();
                Self.loginAttempted = true;

                return sendMessage(name, message);
            }

            throw new Error(error.message);
        });
    }

    /**
     * Returns a rocketchat token
     * @return {Object} userId and authToken
     */
    async function login() {
        const models = Self.app.models;
        const chatConfig = await models.ChatConfig.findOne();
        const uri = `${chatConfig.uri}/login`;
        return send(uri, {
            user: chatConfig.user,
            password: chatConfig.password
        }).then(res => res.data);
    }

    function send(uri, body) {
        if (process.env.NODE_ENV !== 'production') {
            return new Promise(resolve => {
                return resolve({statusCode: 200, message: 'Fake notification sent'});
            });
        }

        const options = {
            method: 'POST',
            uri: uri,
            body: body,
            headers: {'content-type': 'application/json'},
            json: true
        };

        if (Self.token) {
            options.headers['X-Auth-Token'] = Self.token.authToken;
            options.headers['X-User-Id'] = Self.token.userId;
        }

        return request(options);
    }
};