const { Controller } = require('libflitter')

class AuthController extends Controller {
    static get services() {
        return [...super.services, 'models', 'auth', 'MFA', 'output', 'configs']
    }

    async get_users(req, res, next) {
        const User = this.models.get('auth:User')
        const users = await User.find()
        const data = []

        for ( const user of users ) {
            if ( !req.user.can(`auth:user:${user.id}:view`) && req.user.id !== user.id) continue
            data.push(await user.to_api())
        }

        return res.api(data)
    }

    async get_roles(req, res, next) {
        const role_config = this.configs.get('auth.roles')
        const data = []
        for ( const role_name in role_config ) {
            if ( !role_config.hasOwnProperty(role_name) ) continue
            data.push({
                role: role_name,
                permissions: role_config[role_name],
            })
        }

        return res.api(data)
    }

    async validate_username(req, res, next) {
        let is_valid = true

        if ( !req.body.username ) is_valid = false

        if ( is_valid ) {
            const User = this.models.get('auth:User')
            const user = await User.findOne({uid: req.body.username})
            if ( !user || !user.can_login ) is_valid = false
        }

        return res.api({ is_valid })
    }

    // TODO XSRF Token
    /*
     * Request Params:
     *  - username
     *  - password
     *  - [create_session = false]
     */
    async attempt(req, res, next) {
        const flitter = this.auth.get_provider('flitter')

        const errors = await flitter.validate_login(req.body)
        if ( errors && errors.length > 0 )
            return res.status(400)
                .message(`Unable to complete authentication: one or more errors occurred`)
                .api({ errors })

        const login_args = await flitter.get_login_args(req.body)
        const user = await flitter.login.apply(flitter, login_args)

        if ( !user )
            return res.status(200)
                .message(`Invalid username or password.`)
                .api({
                    message: `Invalid username or password.`,
                    success: false,
                })

        if ( req.body.create_session )
            await flitter.session(req, user)

        let destination = this.configs.get('auth.default_login_route')
        if ( req.session.auth.flow ) {
            destination = req.session.auth.flow
        }

        if ( user.mfa_enabled && !req.session.mfa_remember ) {
            req.session.auth.in_dmz = true
            destination = '/auth/mfa/challenge'
        }

        if ( req.session?.auth?.message )
            delete req.session.auth.message

        // If we're doing a trust flow, check the grant
        if ( req.body.grant_code && req.trust.has_flow() ) {
            if ( req.trust.check_grant(req.body.grant_code) ) {
                req.trust.grant(req.trust.flow_scope())

                // Trust re-verification is granted,
                // but the user might still need to verify MFA
                const next = req.trust.end()
                if ( req.session.auth.in_dmz ) {
                    req.session.auth.flow = next
                } else {
                    destination = next
                }
            } else {
                return res.status(401)
                    .message(`Unable to grant trust. Grant token is invalid.`)
                    .api()
            }
        }

        return res.api({
            success: true,
            session_created: !!req.body.create_session,
            next: destination,
        })
    }

    async generate_mfa_key(req, res, next) {
        if ( req.user.mfa_enabled )
            return res.status(400)
                .message(`MFA already configured for user. Cannot fetch key.`)
                .api()

        const MFAToken = this.models.get('auth:MFAToken')
        const secret = await this.MFA.secret(req.user)

        req.user.mfa_token = new MFAToken({
            secret: secret.base32,
            otpauth_url: secret.otpauth_url
        }, req.user)
        await req.user.save()

        return res.api({
            success: true,
            secret: secret.base32,
            otpauth_url: secret.otpauth_url,
            qr_code: await this.MFA.qr_code(secret)
        })
    }

    async attempt_mfa(req, res, next) {
        if ( !req.user.mfa_token )
            return res.status(400)
                .message(`The user does not have MFA configured.`)
                .api()

        const code = req.body.verify_code
        const token = req.user.mfa_token
        const is_valid = token.verify(code)

        let next_destination = undefined
        if ( is_valid ) {
            req.session.auth.in_dmz = false
            next_destination = req.session.auth.flow || this.configs.get('auth.default_login_route')
            delete req.session.auth.flow
        }

        req.session.mfa_remember = true

        return res.api({
            success: true,
            verify_code: code,
            is_valid,
            next_destination,
        })
    }

    async enable_mfa(req, res, next) {
        if ( !req.user.mfa_token )
            return res.status(400)
                .message(`The user does not have an MFA token configured.`)
                .api()

        req.user.mfa_enabled = true
        req.user.mfa_enable_date = new Date
        req.user.save()

        // invalidate existing tokens and other logins
        const flitter = await this.auth.get_provider('flitter')
        await flitter.logout(req)
        await req.user.kickout()

        return res.api({success: true, mfa_enabled: req.user.mfa_enabled})
    }

    async disable_mfa(req, res, next) {
        if ( !req.user.mfa_enabled )
            return res.status(400)
                .message('The user does not have MFA enabled.')
                .api()

        req.user.mfa_enabled = false
        delete req.user.mfa_enable_date
        delete req.user.mfa_token
        req.user.app_passwords = []
        await req.user.save()

        // invalidate existing login tokens and logins
        const flitter = await this.auth.get_provider('flitter')
        await flitter.logout(req)
        await req.user.kickout()

        return res.api({success: true, mfa_enabled: req.user.mfa_enabled})
    }

    async get_mfa_enable_date(req, res, next) {
        if ( !req.user.mfa_enabled )
            return res.api({ mfa_enabled: false })

        return res.api({ mfa_enabled: true, mfa_enable_date: req.user.mfa_enable_date })
    }
}

module.exports = exports = AuthController