# direction: down
vars {
    d2-config {
        sketch: true
        center: true
    }
}

Start: "User clicks\n\"Sign in with Google\"" {
    style.fill: "#e3f2fd"
}

GoogleAuth: "Google OAuth\nAuthentication" {
    style.fill: "#e3f2fd"
}

Handler: "GoogleAuthRegistrationHandler\n.createUser() called" {
    style.fill: "#fff3e0"
}

ExtractEmail: "Extract email from\nGoogle OAuth data" {
    style.fill: "#fff3e0"
}

QueryUser: "Query User by\nUsername = email + '.smi'" {
    style.fill: "#fff3e0"
}

Decision: "User found?" {
    shape: diamond
    style.fill: "#f3e5f5"
}

Success: "Return User\n(login successful)" {
    style.fill: "#e8f5e9"
}

Error: "Throw exception\nwith guidance" {
    style.fill: "#ffebee"
}

ErrorMessage: "User sees error message" {
    style.fill: "#ffebee"
}

DonorboxLink: "Donorbox signup link\n(new members)" {
    style.fill: "#fff9c4"
}

WebdevContact: "webdev contact info\n(existing members)" {
    style.fill: "#fff9c4"
}

Start -> GoogleAuth
GoogleAuth -> Handler
Handler -> ExtractEmail
ExtractEmail -> QueryUser
QueryUser -> Decision
Decision -> Success: yes
Decision -> Error: no
Error -> ErrorMessage
ErrorMessage -> DonorboxLink
ErrorMessage -> WebdevContact