package aws

import (
	"fmt"
	"math/rand"
	"testing"
	"time"

	"github.com/hashicorp/terraform/helper/resource"
	"github.com/hashicorp/terraform/terraform"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/awserr"
	"github.com/aws/aws-sdk-go/service/rds"
)

func TestAccAWSRDSCluster_basic(t *testing.T) {
	var v rds.DBCluster

	resource.Test(t, resource.TestCase{
		PreCheck:     func() { testAccPreCheck(t) },
		Providers:    testAccProviders,
		CheckDestroy: testAccCheckAWSClusterDestroy,
		Steps: []resource.TestStep{
			resource.TestStep{
				Config: testAccAWSClusterConfig,
				Check: resource.ComposeTestCheckFunc(
					testAccCheckAWSClusterExists("aws_rds_cluster.default", &v),
				),
			},
		},
	})
}

func testAccCheckAWSClusterDestroy(s *terraform.State) error {
	for _, rs := range s.RootModule().Resources {
		if rs.Type != "aws_rds_cluster" {
			continue
		}

		// Try to find the Group
		conn := testAccProvider.Meta().(*AWSClient).rdsconn
		var err error
		resp, err := conn.DescribeDBClusters(
			&rds.DescribeDBClustersInput{
				DBClusterIdentifier: aws.String(rs.Primary.ID),
			})

		if err == nil {
			if len(resp.DBClusters) != 0 &&
				*resp.DBClusters[0].DBClusterIdentifier == rs.Primary.ID {
				return fmt.Errorf("DB Cluster %s still exists", rs.Primary.ID)
			}
		}

		// Return nil if the cluster is already destroyed
		if awsErr, ok := err.(awserr.Error); ok {
			if awsErr.Code() == "DBClusterNotFound" {
				return nil
			}
		}

		return err
	}

	return nil
}

func testAccCheckAWSClusterExists(n string, v *rds.DBCluster) resource.TestCheckFunc {
	return func(s *terraform.State) error {
		rs, ok := s.RootModule().Resources[n]
		if !ok {
			return fmt.Errorf("Not found: %s", n)
		}

		if rs.Primary.ID == "" {
			return fmt.Errorf("No DB Instance ID is set")
		}

		conn := testAccProvider.Meta().(*AWSClient).rdsconn
		resp, err := conn.DescribeDBClusters(&rds.DescribeDBClustersInput{
			DBClusterIdentifier: aws.String(rs.Primary.ID),
		})

		if err != nil {
			return err
		}

		for _, c := range resp.DBClusters {
			if *c.DBClusterIdentifier == rs.Primary.ID {
				*v = *c
				return nil
			}
		}

		return fmt.Errorf("DB Cluster (%s) not found", rs.Primary.ID)
	}
}

// Add some random to the name, to avoid collision
var testAccAWSClusterConfig = fmt.Sprintf(`
resource "aws_rds_cluster" "default" {
  cluster_identifier = "tf-aurora-cluster-%d"
  availability_zones = ["us-west-2a","us-west-2b","us-west-2c"]
  database_name = "mydb"
  master_username = "foo"
  master_password = "mustbeeightcharaters"
}`, rand.New(rand.NewSource(time.Now().UnixNano())).Int())