'use strict'
const JWT = require('jsonwebtoken')
const crypto = require('crypto')

const hashToken = async token => {
    const salt = process.env.APP_SESSION_SALT
    try {
        return crypto.createHmac('sha256', salt).update(token).digest('hex')
    } catch (err) {
        throw new Error(err.message)
    }
}

const createToken = (data, expiration = 600) => {
    const key = process.env.APP_SECRET
    const obj = {}

    Object.assign(obj, { ...data })
    return JWT.sign(obj, key, { expiresIn: expiration })
}

const validateToken = token => {
    const key = process.env.APP_SECRET
    try {
        return JWT.verify(token, key)
    } catch (err) {
        return { payload: null, message: err.message }
    }
}

module.exports = options => {
    return {
        key: options.jwtKey,
        verifyOptions: {
            algorithms: ['HS256'],
        },
        // TODO: Naming conventions need to be reversed again??
        validate: async (decoded, request, h) => {
            const sessionTokenFromHeaders = request.headers.authorization
            const hashedSessionTokenFromHeaders = await hashToken(
                sessionTokenFromHeaders,
            )
            const activeSession =
                request.server.app.activeSessions[hashedSessionTokenFromHeaders]
            if (!activeSession)
                throw new Error(
                    `No session found for ${hashedSessionTokenFromHeaders}`,
                )

            const sessionToken = activeSession.sessionToken
            const accessToken = activeSession.accessToken
            const validatedSessionToken = validateToken(sessionToken)
            const validatedAccessToken = validateToken(accessToken)
            if (!validatedAccessToken.payload) {
                console.log('accessToken no longer valid, reissuing... ')
                activeSession.accessToken = createToken(
                    { payload: validatedSessionToken.payload },
                    // NOTE: Expiration of new sessionToken set for 200 seconds (testing)
                    100,
                )
            }
            try {
                const validatedJwt = JWT.verify(
                    sessionToken,
                    process.env.APP_SECRET,
                )
                return { isValid: true, credentials: validatedJwt.email }
            } catch (err) {
                return { isValid: false, error: err.message }
            }
        },
    }
}