// Copyright 2017 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package internal

import (
	"context"
	"testing"

	"github.com/google/go-cmp/cmp"
	"golang.org/x/oauth2"
	"golang.org/x/oauth2/google"
)

type dummyTokenSource struct {
	oauth2.TokenSource
}

func TestTokenSource(t *testing.T) {
	ctx := context.Background()

	// Pass in a TokenSource, get it back.
	ts := &dummyTokenSource{}
	ds := &DialSettings{TokenSource: ts}
	got, err := Creds(ctx, ds)
	if err != nil {
		t.Fatal(err)
	}
	want := &google.DefaultCredentials{TokenSource: ts}
	if !cmp.Equal(got, want) {
		t.Error("did not get the same TokenSource back")
	}

	// If both a file and TokenSource are passed, the file takes precedence
	// (existing behavior).
	// TODO(jba): make this an error?
	ds = &DialSettings{
		TokenSource:     ts,
		CredentialsFile: "service-account.json",
	}
	got, err = Creds(ctx, ds)
	if err != nil {
		t.Fatal(err)
	}
	if cmp.Equal(got, want) {
		t.Error("got the same TokenSource back, wanted one from the JSON file")
	}
	// TODO(jba): find a way to test the call to google.DefaultTokenSource.
}

func TestDefaultServiceAccount(t *testing.T) {
	ctx := context.Background()

	// Load a valid JSON file. No way to really test the contents; we just
	// verify that there is no error.
	ds := &DialSettings{CredentialsFile: "service-account.json"}
	if _, err := Creds(ctx, ds); err != nil {
		t.Errorf("got %v, wanted no error", err)
	}

	// Load valid JSON. No way to really test the contents; we just
	// verify that there is no error.
	ds = &DialSettings{CredentialsJSON: []byte(validServiceAccountJSON)}
	if _, err := Creds(ctx, ds); err != nil {
		t.Errorf("got %v, wanted no error", err)
	}
}

func TestJWTWithAudience(t *testing.T) {
	ctx := context.Background()

	// Load a valid JSON file. No way to really test the contents; we just
	// verify that there is no error.
	ds := &DialSettings{CredentialsFile: "service-account.json", Audiences: []string{"foo"}}
	if _, err := Creds(ctx, ds); err != nil {
		t.Errorf("got %v, wanted no error", err)
	}

	// Load valid JSON. No way to really test the contents; we just
	// verify that there is no error.
	ds = &DialSettings{CredentialsJSON: []byte(validServiceAccountJSON), Audiences: []string{"foo"}}
	if _, err := Creds(ctx, ds); err != nil {
		t.Errorf("got %v, wanted no error", err)
	}
}

func TestOAuth(t *testing.T) {
	ctx := context.Background()

	// Load a valid JSON file. No way to really test the contents; we just
	// verify that there is no error.
	ds := &DialSettings{CredentialsFile: "service-account.json", Scopes: []string{"foo"}}
	if _, err := Creds(ctx, ds); err != nil {
		t.Errorf("got %v, wanted no error", err)
	}

	// Load valid JSON. No way to really test the contents; we just
	// verify that there is no error.
	ds = &DialSettings{CredentialsJSON: []byte(validServiceAccountJSON), Scopes: []string{"foo"}}
	if _, err := Creds(ctx, ds); err != nil {
		t.Errorf("got %v, wanted no error", err)
	}
}

const validServiceAccountJSON = `{
  "type": "service_account",
  "project_id": "dumba-504",
  "private_key_id": "adsfsdd",
  "private_key": "-----BEGIN PRIVATE KEY-----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\nL54zu6Y9GbjLgn6BtfhLHG4v\n-----END PRIVATE KEY-----\n",
  "client_email": "dumba-504@appspot.gserviceaccount.com",
  "client_id": "111",
  "auth_uri": "https://accounts.google.com/o/oauth2/auth",
  "token_uri": "https://accounts.google.com/o/oauth2/token",
  "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
  "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/dumba-504%40appspot.gserviceaccount.com"
}`