package google

import (
	"fmt"

	"regexp"

	"github.com/hashicorp/terraform/helper/schema"
	"github.com/hashicorp/terraform/helper/validation"
	computeBeta "google.golang.org/api/compute/v0.beta"
	"google.golang.org/api/compute/v1"
)

const (
	addressTypeExternal = "EXTERNAL"
	addressTypeInternal = "INTERNAL"
)

var (
	computeAddressIdTemplate = "projects/%s/regions/%s/addresses/%s"
	computeAddressLinkRegex  = regexp.MustCompile("projects/(.+)/regions/(.+)/addresses/(.+)$")
	AddressBaseApiVersion    = v1
	AddressVersionedFeatures = []Feature{
		{Version: v0beta, Item: "address_type", DefaultValue: addressTypeExternal},
		{Version: v0beta, Item: "subnetwork"},
	}
)

func resourceComputeAddress() *schema.Resource {
	return &schema.Resource{
		Create: resourceComputeAddressCreate,
		Read:   resourceComputeAddressRead,
		Delete: resourceComputeAddressDelete,
		Importer: &schema.ResourceImporter{
			State: resourceComputeAddressImportState,
		},

		SchemaVersion: 1,
		MigrateState:  resourceComputeAddressMigrateState,

		// These fields mostly correlate to the fields in the beta Address
		// resource. See https://cloud.google.com/compute/docs/reference/beta/addresses#resource
		Schema: map[string]*schema.Schema{
			"name": &schema.Schema{
				Type:     schema.TypeString,
				Required: true,
				ForceNew: true,
			},

			"address_type": &schema.Schema{
				Type:     schema.TypeString,
				Optional: true,
				ForceNew: true,
				Default:  addressTypeExternal,
				ValidateFunc: validation.StringInSlice(
					[]string{addressTypeInternal, addressTypeExternal}, false),
			},

			"subnetwork": &schema.Schema{
				Type:             schema.TypeString,
				Optional:         true,
				ForceNew:         true,
				Computed:         true,
				DiffSuppressFunc: linkDiffSuppress,
			},

			// address will be computed unless it is specified explicitly.
			// address may only be specified for the INTERNAL address_type.
			"address": &schema.Schema{
				Type:     schema.TypeString,
				Optional: true,
				ForceNew: true,
				Computed: true,
			},

			"project": &schema.Schema{
				Type:     schema.TypeString,
				Optional: true,
				Computed: true,
				ForceNew: true,
			},

			"region": &schema.Schema{
				Type:     schema.TypeString,
				Optional: true,
				Computed: true,
				ForceNew: true,
			},

			"self_link": &schema.Schema{
				Type:     schema.TypeString,
				Computed: true,
			},
		},
	}
}

func resourceComputeAddressCreate(d *schema.ResourceData, meta interface{}) error {
	computeApiVersion := getComputeApiVersion(d, AddressBaseApiVersion, AddressVersionedFeatures)
	config := meta.(*Config)

	region, err := getRegion(d, config)
	if err != nil {
		return err
	}

	project, err := getProject(d, config)
	if err != nil {
		return err
	}

	// Build the address parameter
	v0BetaAddress := &computeBeta.Address{
		Name:        d.Get("name").(string),
		AddressType: d.Get("address_type").(string),
		Subnetwork:  d.Get("subnetwork").(string),
	}

	if desired, ok := d.GetOk("address"); ok {
		v0BetaAddress.Address = desired.(string)
	}

	var op interface{}
	switch computeApiVersion {
	case v1:
		v1Address := &compute.Address{}
		err = Convert(v0BetaAddress, v1Address)
		if err != nil {
			return err
		}
		op, err = config.clientCompute.Addresses.Insert(
			project, region, v1Address).Do()
	case v0beta:
		op, err = config.clientComputeBeta.Addresses.Insert(
			project, region, v0BetaAddress).Do()
	}
	if err != nil {
		return fmt.Errorf("Error creating address: %s", err)
	}

	// It probably maybe worked, so store the ID now
	d.SetId(computeAddressId{
		Project: project,
		Region:  region,
		Name:    v0BetaAddress.Name,
	}.canonicalId())

	err = computeSharedOperationWait(config.clientCompute, op, project, "Creating Address")
	if err != nil {
		return err
	}

	return resourceComputeAddressRead(d, meta)
}

func resourceComputeAddressRead(d *schema.ResourceData, meta interface{}) error {
	computeApiVersion := getComputeApiVersion(d, AddressBaseApiVersion, AddressVersionedFeatures)
	config := meta.(*Config)

	addressId, err := parseComputeAddressId(d.Id(), config)
	if err != nil {
		return err
	}

	addr := &computeBeta.Address{}
	switch computeApiVersion {
	case v1:
		v1Address, err := config.clientCompute.Addresses.Get(
			addressId.Project, addressId.Region, addressId.Name).Do()
		if err != nil {
			return handleNotFoundError(err, d, fmt.Sprintf("Address %q", d.Get("name").(string)))
		}

		err = Convert(v1Address, addr)
		if err != nil {
			return err
		}

	case v0beta:
		var err error
		addr, err = config.clientComputeBeta.Addresses.Get(
			addressId.Project, addressId.Region, addressId.Name).Do()
		if err != nil {
			return handleNotFoundError(err, d, fmt.Sprintf("Address %q", d.Get("name").(string)))
		}

	}

	// The v1 API does not include an AddressType field, as it only supports
	// external addresses. An empty AddressType implies a v1 address that has
	// been converted to v0beta, and thus an EXTERNAL address.
	d.Set("address_type", addr.AddressType)
	if addr.AddressType == "" {
		d.Set("address_type", addressTypeExternal)
	}
	d.Set("subnetwork", ConvertSelfLinkToV1(addr.Subnetwork))
	d.Set("address", addr.Address)
	d.Set("self_link", ConvertSelfLinkToV1(addr.SelfLink))
	d.Set("name", addr.Name)
	d.Set("project", addressId.Project)
	d.Set("region", GetResourceNameFromSelfLink(addr.Region))

	return nil
}

func resourceComputeAddressDelete(d *schema.ResourceData, meta interface{}) error {
	computeApiVersion := getComputeApiVersion(d, AddressBaseApiVersion, AddressVersionedFeatures)
	config := meta.(*Config)

	addressId, err := parseComputeAddressId(d.Id(), config)
	if err != nil {
		return err
	}

	// Delete the address
	var op interface{}
	switch computeApiVersion {
	case v1:
		op, err = config.clientCompute.Addresses.Delete(
			addressId.Project, addressId.Region, addressId.Name).Do()
		if err != nil {
			return fmt.Errorf("Error deleting address: %s", err)
		}
	case v0beta:
		op, err = config.clientComputeBeta.Addresses.Delete(
			addressId.Project, addressId.Region, addressId.Name).Do()
		if err != nil {
			return fmt.Errorf("Error deleting address: %s", err)
		}
	}

	err = computeSharedOperationWait(config.clientCompute, op, addressId.Project, "Deleting Address")
	if err != nil {
		return err
	}

	d.SetId("")
	return nil
}

func resourceComputeAddressImportState(d *schema.ResourceData, meta interface{}) ([]*schema.ResourceData, error) {
	config := meta.(*Config)

	addressId, err := parseComputeAddressId(d.Id(), config)
	if err != nil {
		return nil, err
	}

	d.SetId(addressId.canonicalId())

	return []*schema.ResourceData{d}, nil
}