const jwtSecret   = '4atikJgznM'
const jwt         = require('jsonwebtoken')

const express           = require('express');
const express_graphql   = require('express-graphql');

const { buildSchema, printSchema, GraphQLString } = require('graphql');
const expand = require('mm-graphql/expand')
const fs     = require('fs')
const uploadPath = `${__dirname}/public/images/`;
const upload  = require('multer')({ dest: uploadPath })


;(async () => {

    const {Savable, slice, getModels} = await require('./models.js')()
    const { jwtGQLAnon, jwtCheck } = require('mm-graphql/jwt')

    let schema = buildSchema(`
        type User {
             _id: ID
             createdAt: String
             login: String
             nick : String
             acl: [String]

             avatar: Media
             chats: [Chat]
        }

        input UserInput {
             _id: ID
             login: String
             nick : String
             password: String
             acl: [String]
             avatar: MediaInput
             chats: [ChatInput]
        }

        type Message {
             _id: ID
             createdAt: String
             owner: User
             chat: Chat
             text: String
             media: [Media]
             replies: [Message]
             replyTo: Message
             forwarded: Message
             forwardWith: [Message]
        }

        input MessageInput {
             _id: ID
             text: String

             chat: ChatInput
             media: [MediaInput]
             replies: [MessageInput]
             replyTo: MessageInput
             forwarded: MessageInput
             forwardWith: [MessageInput]
        }


        type Chat {
            _id: ID
            createdAt: String
            lastModified: String
            lastMessage: Message
            owner: User

            title: String
            members: [User]
            messages: [Message]
            avatar: Media
        }


        input ChatInput {
            _id: ID

            title: String
            members: [UserInput]
            messages: [MessageInput]
        }

        type Media {
            _id: ID,
            createdAt: String

            owner: User
            text: String,
            url: String,
            originalFileName: String,
            type: String


            userAvatar: User
            chatAvatars: [Chat]
            messages: [Message]
        }

        input MediaInput {
            _id: ID,
            text: String,
            userAvatar: UserInput,
            chatAvatars: [ChatInput]
            messages: [MessageInput]
        }
    `);

    schema = expand(schema, {
        login:{
            type: GraphQLString,
            args: {login:    {type: GraphQLString},
                   password: {type: GraphQLString},
            },
            async resolve(root, {login, password}, context, info){
                const Savable =  context.models.Savable 
                if (!login || !password) return null;
                const user    =  await Savable.m.User.findOne({login, password})
                console.log(user, {login, password})
                if (!user)
                    return null;

                const token = jwt.sign({ sub: {id: user._id, login, acl: user.acl}}, jwtSecret); //подписывам токен нашим ключем
                return token
            }
        }
    })
    console.log(printSchema(schema))

    const app = express();
    const http              = require('http').Server(app);
    const io                = require('socket.io')(http);

    app.use(require('cors')())
    app.use(express.static('public'));
    app.use('/graphql', express_graphql(jwtGQLAnon({schema, createContext: decoded => getModels(decoded, messageWatcher, chatWatcher), graphiql: true, secret: jwtSecret})))


    app.post('/upload', upload.single('media'), async (req, res, next) => {
        let decoded;
        if (decoded = jwtCheck(req, jwtSecret)){
            console.log('SOME UPLOAD', decoded, req.file)

            let {models: {Media }} = await getModels(decoded.sub)
            let media = await Media.fromFileData(req.file)
            res.end(JSON.stringify({_id: media._id, url: media.url}))
        }
        else {
            res.status(503).send('permission denied')
        }
    })

    app.use(express.static('public'));

    const sockets = {}

    async function messageWatcher(msg){
        console.log('NEW MSG', msg.text, msg.chat.title, msg.owner.login)
        for (let [id,{user, socket}] of Object.entries(sockets)){
            if (user.chats.some(chat => chat._id.toString() === msg.chat._id.toString())){
                let {_id, createdAt, text, chat, media, replyTo, forwarded, owner} = msg
                await chat;
                await Promise.all(media || []);
                await replyTo;
                await forwarded;
                owner = await owner;
                await owner.avatar
                console.log('MEDIA', media)
                socket.emit('msg', {_id, createdAt: createdAt.getTime(), text, chat: chat && {_id: chat._id, title: chat.title},
                                                          media: media && media.map(media => ({_id: media._id, url: media.url, type: media.type})),
                                                          replyTo: replyTo && {_id: replyTo._id, text: replyTo.text},
                                                          forwarded: forwarded && {_id: forwarded._id, text: forwarded.text},
                                                          owner: {_id: owner._id, login: owner.login, nick: owner.nick, avatar: owner.avatar && {url: owner.avatar.url}}})
            }
        }
    }

    async function chatWatcher({_loadRelations, members, _id, createdAt, title, messages, avatar, lastModified}){

        console.log('CHAT SAVE', _id, title)
        for (let [id,socketData] of Object.entries(sockets)){
            const {user, socket} = socketData
            const isMember = members.some(member => member._id.toString() === user._id.toString())
            const wasMember  =(_loadRelations.members && _loadRelations.members.some(member => member._id.toString() === user._id.toString())) 
            if (isMember || wasMember){
                //await chat;
                //await media;
                //await replyTo;
                //await forwarded;
                await avatar;
                await Promise.all(members)
                //owner = await owner;
                console.log('EMIT', _id, createdAt.getTime(), title)
                socket.emit(isMember ? 'chat' : 'chat_left', {_id, createdAt: createdAt.getTime(), title, avatar: avatar && {_id: avatar._id, url: avatar.url}, members: members.map(({_id, login, nick}) => ({_id, login, nick})), lastModified})
                socketData.user = (await getModels(socketData.decoded.sub)).thisUser //re-read chat permissions 
            }
        }
    }

    io.on('connection', socket => {
        console.log('connect', socket.id)
        socket.on('disconnect', () => {
            console.log('disconnect', socket.id)
            delete sockets[socket.id]
        })

        socket.on('jwt', async token =>{
            let decoded; 
            try {
                decoded = jwt.verify(token, jwtSecret)
            }
            catch (e){
                socket.emit('jwt_fail', e)
                return
            }
            socket.emit('jwt_ok', decoded)
            //sockets[socket.id] = decoded
            sockets[socket.id] = {decoded, user: (await getModels(decoded.sub)).thisUser, socket}
        })
    })


    let socketPath = 5001

    http.listen(socketPath, () => {
        console.log(`Express GraphQL Server Now Running On ${socketPath}/graphql`);
    });
})()