import { google } from 'googleapis'
import type { GoogleUserInfo } from './types.js'
export class GoogleAuthService {
private oauth2Client: any
private clientId: string
private clientSecret: string
private redirectUri: string
constructor(clientId: string, clientSecret: string, redirectUri: string) {
this.clientId = clientId
this.clientSecret = clientSecret
this.redirectUri = redirectUri
this.oauth2Client = new google.auth.OAuth2(clientId, clientSecret, redirectUri)
}
/**
* Generate Google OAuth authorization URL
*/
generateAuthUrl(state: string): string {
const scopes = [
'https://www.googleapis.com/auth/calendar',
'https://www.googleapis.com/auth/calendar.events',
'https://www.googleapis.com/auth/userinfo.email',
'https://www.googleapis.com/auth/userinfo.profile',
]
return this.oauth2Client.generateAuthUrl({
access_type: 'offline',
scope: scopes,
state: state,
prompt: 'consent', // Force consent screen to get refresh token
})
}
/**
* Exchange authorization code for Google tokens
*/
async exchangeCodeForTokens(code: string): Promise<{
access_token: string
refresh_token?: string
token_type: string
expiry_date?: number
}> {
try {
// Create a fresh OAuth client for each request to avoid credential conflicts
const freshOAuth2Client = new google.auth.OAuth2(
this.clientId,
this.clientSecret,
this.redirectUri
)
const { tokens } = await freshOAuth2Client.getToken(code)
freshOAuth2Client.setCredentials(tokens)
return {
access_token: tokens.access_token!,
refresh_token: tokens.refresh_token,
token_type: tokens.token_type || 'Bearer',
expiry_date: tokens.expiry_date,
}
} catch (error) {
console.error('Google token exchange error:', error)
throw new Error(`Failed to exchange authorization code: ${error}`)
}
}
/**
* Get user information from Google
*/
async getUserInfo(accessToken: string): Promise<GoogleUserInfo> {
try {
// Create a fresh OAuth client for each request
const freshOAuth2Client = new google.auth.OAuth2(
this.clientId,
this.clientSecret,
this.redirectUri
)
freshOAuth2Client.setCredentials({ access_token: accessToken })
const oauth2 = google.oauth2({ version: 'v2', auth: freshOAuth2Client })
const response = await oauth2.userinfo.get()
const userInfo = response.data
return {
id: userInfo.id!,
email: userInfo.email!,
name: userInfo.name!,
picture: userInfo.picture,
verified_email: userInfo.verified_email || false,
}
} catch (error) {
console.error('Google user info error:', error)
throw new Error(`Failed to get user info: ${error}`)
}
}
/**
* Refresh Google access token
*/
async refreshAccessToken(
refreshToken: string
): Promise<{ access_token: string; expires_in: number }> {
try {
this.oauth2Client.setCredentials({ refresh_token: refreshToken })
const { credentials } = await this.oauth2Client.refreshAccessToken()
return {
access_token: credentials.access_token!,
expires_in: credentials.expiry_date
? Math.floor((credentials.expiry_date - Date.now()) / 1000)
: 3600,
}
} catch (error) {
throw new Error(`Failed to refresh access token: ${error}`)
}
}
}
