const ObjectID    = require("mongodb").ObjectID;
const jwt         = require('jsonwebtoken')
const jwtSecret   = 'CbymrfGfnB'

const express = require('express');
const express_graphql = require('express-graphql');
const { buildSchema, GraphQLObjectType, GraphQLString, GraphQLList, GraphQLSchema, printSchema } = require('graphql');



function mmExpandSchema(gqlSchema){
    const types    = {}
    const _typeMap = gqlSchema.getTypeMap()

    const buildInTypes = ['Query',  'Mutation',  'ID',  'Float',  "String",  'Int',  'Boolean',
                          'Query!', 'Mutation!', 'ID!', 'Float!', "String!", 'Int!', 'Boolean!' ]


    async function argToSavables(arg, outputTypeName, Savable){
        console.log('argToSavables', arg)
        const entity = arg._id ? await Savable.m[outputTypeName].findOne({_id: ObjectID(arg._id)}) :
                                 new Savable.classes[outputTypeName]({})
        const {_id, ...data} = arg;
        const type = _typeMap[outputTypeName + 'Input']
        const fields = type.getFields()

        for(let [fieldName, value] of Object.entries(data)){
            let typeName = fields[fieldName].type.toString()

            if (!buildInTypes.includes(typeName)){
                console.log('recursive', arg[fieldName], typeName)
                if (typeName[0] === '['){
                    const nestedTypeName = typeName.slice(1,-6)
                    console.log('array',nestedTypeName)

                    entity[fieldName] = []
                    for (let nestedArg of value){
                        const nestedEntity = await argToSavables(nestedArg, nestedTypeName, Savable)
                        entity[fieldName].push(nestedEntity)
                    }
                }
                else {
                    const nestedTypeName = typeName.slice(0,-5)
                    console.log('one', nestedTypeName)
                    entity[fieldName] = await argToSavables(value, nestedTypeName, Savable)
                }
            }
            else {
                entity[fieldName] = value
            }
        }
        return await entity.save()
    }


    let queryFields     = _typeMap.Query    ? _typeMap.Query.getFields()    : {}
    let mutationFields  = _typeMap.Mutation ? _typeMap.Mutation.getFields() : {}

    for (let [typeName, type] of Object.entries(_typeMap)) 
        if (!buildInTypes.includes(typeName) && 
            !typeName.startsWith('__')){

            if (typeName.endsWith('Input')){
                let outputTypeName = typeName.substr(0, typeName.length - 'Input'.length)
                if (outputTypeName in _typeMap){
                    types[outputTypeName] = type

                    const find = {
                        type: GraphQLList(_typeMap[outputTypeName]),
                        args: {query: {type: GraphQLString}},
                        async resolve(root, args, context, info){
                            //console.log(root, args, context, info)

                            const Savable = context.models.SlicedSavable || context.models.Savable 
                            args = JSON.parse(args.query)
                            let results = []

                            for (let result of Savable.m[outputTypeName].find(...args)){
                                try {result = await result} catch (e) { break }
                                results.push(result)
                            }
                            return results;
                        }
                    }
                    queryFields[`${outputTypeName}Find`] = find

                    const findOne = {
                        type: _typeMap[outputTypeName],
                        args: {query: {type: GraphQLString}},
                        async resolve(root, args, context, info){
                            //console.log(root, args, context, info)

                            const Savable = context.models.SlicedSavable || context.models.Savable 
                            args = JSON.parse(args.query)
                            let [query] = args
                            if (query._id && typeof query._id === 'string'){
                                query._id = ObjectID(query._id)
                            }
                            let record = Savable.m[outputTypeName].findOne(query, ...args.slice(1))
                            return record;
                        }
                    }
                    queryFields[`${outputTypeName}FindOne`] = findOne


                    const lowerCaseName = outputTypeName[0].toLowerCase() + outputTypeName.slice(1)

                    const del = {
                        type: _typeMap[outputTypeName],
                        args: {[lowerCaseName]: {type: _typeMap[typeName]}},
                        async resolve(root, args, context, info){
                            //console.log(root, args, context, info)

                            const Savable = context.models.SlicedSavable || context.models.Savable 
                            const arg     = args[lowerCaseName]
                            if (! ('_id' in arg)){
                                return null;
                            }
                            let entity = await Savable.m[outputTypeName].findOne({_id: ObjectID(arg._id)})
                            if (entity){
                                let copy = {...record}
                                await entity.delete()
                                return copy;
                            }

                            return entity;
                        }
                    }
                    mutationFields[`${outputTypeName}Delete`] = del

                    const upsert = {
                        type: _typeMap[outputTypeName],
                        args: {[lowerCaseName]: {type: _typeMap[typeName]}},
                        async resolve(root, args, context, info){
                            //console.log(root, args, context, info)

                            const Savable = context.models.SlicedSavable || context.models.Savable 

                            const arg     = args[lowerCaseName]
                            const entity  = argToSavables(args[lowerCaseName], outputTypeName, Savable)

                            return entity;
                        }
                    }
                    mutationFields[`${outputTypeName}Upsert`] = upsert
                }
            }
    }


    let newQuery     = new GraphQLObjectType({name: 'Query', fields: queryFields})
    let newMutation  = new GraphQLObjectType({name: 'Mutation', fields: mutationFields})

    let newSchema = new GraphQLSchema({query: newQuery, mutation: newMutation})
    return newSchema;
}


;(async () => {
    const {Savable, slice, getModels} = await require('./models.js')()

    const jwtGQL = require('./jwt')

    class User extends Savable {
        static get relations(){
            return {
            }
        }
    }
    Savable.addClass(User)


    let schema = buildSchema(`
        type User {
             _id: String
             createdAt: String
             login: String
             nick : String
             orders: [Order]
        }

        input UserInput {
             _id: String
             login: String
             nick : String
        }

        type Category {
            _id: ID,
            createdAt: String
            name: String!,
            goods: [Good]
        }
        input CategoryInput {
            _id: ID,
            name: String,
            goods: [GoodInput]
        }

        type Good {
            _id: ID,
            createdAt: String
            name: String!,
            description: String
            price: Float
            imgUrls: [String]
            orderGoods: [OrderGood]
            categories: [Category]
        }

        input GoodInput {
            _id: ID,
            name: String,
            description: String
            imgUrls: [String]
            price: Float
            categories: [CategoryInput]
        }


        type OrderGood {
            _id: ID,
            createdAt: String
            price: Float,
            count: Float,
            good: Good,
            order: Order
            total: Float
        }

        input OrderGoodInput {
            _id: ID,
            count: Int,
            good: GoodInput,
            order: OrderInput
        }


        type Order {
            _id: ID
            createdAt: String
            orderGoods: [OrderGood]
            total: Float
        }

        input OrderInput {
            _id: ID
            orderGoods: [OrderGoodInput]
        }

    `);

    schema = mmExpandSchema(schema)
    console.log(printSchema(schema))

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

    const anonResolvers = {
        createUser:async function ({login, password}){
            let user =  await Savable.m.User.findOne({login, password})
            if (user)
                return null;
            user = await (new User({login, password})).save()

            user.___owner = user._id.toString()
            user.___permissions = {
                read: ["owner", "user"]
            }

            return await user.save()
        },

        login: async function({login, password}){
            console.log(Savable.classes)
            const user =  await Savable.m.User.findOne({login, password})
            if (!user)
                return null;

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

        changePassword:async function ({login, password, newPassword}){
            const user =  await Savable.m.User.findOne({login, password})
            if (!user) return null;
            user.password = newPassword;
            return await user.save()
        },
    }

    const anonSchema = buildSchema(`
        type Query {
            login(login: String!, password: String!): String
        }
        type Mutation {
            createUser(login: String!, password: String!): User
            changePassword(login: String!, password: String!, newPassword: String!): User
        }

        type User {
             _id: String
             createdAt: String
             login: String
             nick : String
        }

    `)

    app.use('/graphql', express_graphql(jwtGQL({anonSchema, anonResolvers, schema, createContext: getModels, graphiql: true, secret: jwtSecret})))

    app.listen(4000, () => console.log('Express GraphQL Server Now Running On localhost:4000/graphql'));
})()