import { Router } from 'express'
import { AuthorizationCode } from 'simple-oauth2'
import fetch from 'node-fetch'
import { DatabaseConnection, getUser, createUser } from './db/database'
import { UserId } from '../shared/model'
import { SessionService } from './routes'
import { prependBaseUrl } from '../shared/utils'

export function setupOAuth(r: Router, db: DatabaseConnection, sessions: SessionService) {
    const config = {
        client: {
            id: process.env.OAUTH_CLIENT_ID ?? '',
            secret: process.env.OAUTH_CLIENT_SECRET ?? '',
        },
        auth: {
            authorizePath: process.env.OAUTH_AUTH_URL ?? '',
            tokenHost: process.env.OAUTH_TOKEN_HOST ?? '',
            tokenPath: process.env.OAUTH_TOKEN_PATH ?? '',
        },
    }

    const conf = {
        redirect_uri: process.env.OAUTH_REDIRECT_URL ?? '',
        scope: process.env.OAUTH_SCOPES ?? '',
    }

    const client = new AuthorizationCode(config)

    const authorizationUri = client.authorizeURL({
        redirect_uri: conf.redirect_uri,
        scope: conf.scope,
        state: '',
    })

    r.get('/redirect', (req, res) => {
        res.redirect(authorizationUri)
    })

    // Callback service parsing the authorization token and asking for the access token
    r.get('/callback', async (req, res) => {
        const code = req.query.code as string

        const options = {
            code,
            redirect_uri: conf.redirect_uri,
        }

        try {
            const accessToken = await client.getToken(options)

            console.log(accessToken.token.access_token)

            const userInfo = await (
                await fetch(process.env.OAUTH_USER_INFO_URL ?? '', {
                    method: 'GET',
                    headers: {
                        Authorization: 'Bearer ' + accessToken.token.access_token,
                    },
                })
            ).json()

            type UserInfo = { name: string; email: string }

            // Parse user info into a sensible struct
            const authUser = {
                id: (userInfo as UserInfo).email.split('@')[0] as UserId,
                fullName: (userInfo as UserInfo).name
                    .split(' ')
                    .map(s => s.substring(0, 1) + s.substring(1).toLowerCase())
                    .join(' '),
            }

            const user = await getUser(db, authUser.id)
            if (!user) {
                await createUser(db, {
                    id: authUser.id,
                    fullName: authUser.fullName,
                    role: 'student',
                })
            }

            res.cookie('sid', sessions.createSession(authUser.id), { maxAge: 1000 * 60 * 60 * 24 * 7 })

            return res.status(200).redirect(prependBaseUrl('/'))
        } catch (error) {
            console.error('Access Token Error', error.message)
            return res.status(500).redirect(prependBaseUrl(`/error?message=${encodeURIComponent('Autenticazione fallita')}`))
        }
    })
}