package azurerm

import (
	"fmt"
	"log"
	"net/http"
	"regexp"

	"github.com/Azure/azure-sdk-for-go/arm/trafficmanager"
	"github.com/hashicorp/terraform/helper/schema"
	"github.com/hashicorp/terraform/helper/validation"
)

func resourceArmTrafficManagerEndpoint() *schema.Resource {
	return &schema.Resource{
		Create: resourceArmTrafficManagerEndpointCreate,
		Read:   resourceArmTrafficManagerEndpointRead,
		Update: resourceArmTrafficManagerEndpointCreate,
		Delete: resourceArmTrafficManagerEndpointDelete,
		Importer: &schema.ResourceImporter{
			State: schema.ImportStatePassthrough,
		},

		Schema: map[string]*schema.Schema{
			"name": {
				Type:     schema.TypeString,
				Required: true,
				ForceNew: true,
			},

			"type": {
				Type:         schema.TypeString,
				Required:     true,
				ForceNew:     true,
				ValidateFunc: validation.StringInSlice([]string{"azureEndpoints", "nestedEndpoints", "externalEndpoints"}, false),
			},

			"profile_name": {
				Type:     schema.TypeString,
				Required: true,
				ForceNew: true,
			},

			"target": {
				Type:     schema.TypeString,
				Optional: true,
				// when targeting an Azure resource the FQDN of that resource will be set as the target
				Computed: true,
			},

			"target_resource_id": {
				Type:     schema.TypeString,
				Optional: true,
			},

			"endpoint_status": {
				Type:     schema.TypeString,
				Optional: true,
				Computed: true,
			},

			"weight": {
				Type:         schema.TypeInt,
				Optional:     true,
				Computed:     true,
				ValidateFunc: validation.IntBetween(1, 1000),
			},

			"priority": {
				Type:         schema.TypeInt,
				Optional:     true,
				Computed:     true,
				ValidateFunc: validation.IntBetween(1, 1000),
			},

			"endpoint_location": {
				Type:     schema.TypeString,
				Optional: true,
				// when targeting an Azure resource the location of that resource will be set on the endpoint
				Computed:  true,
				StateFunc: azureRMNormalizeLocation,
			},

			"min_child_endpoints": {
				Type:     schema.TypeInt,
				Optional: true,
			},

			"resource_group_name": {
				Type:             schema.TypeString,
				Required:         true,
				ForceNew:         true,
				DiffSuppressFunc: resourceAzurermResourceGroupNameDiffSuppress,
			},
		},
	}
}

func resourceArmTrafficManagerEndpointCreate(d *schema.ResourceData, meta interface{}) error {
	client := meta.(*ArmClient).trafficManagerEndpointsClient

	log.Printf("[INFO] preparing arguments for ARM TrafficManager Endpoint creation.")

	name := d.Get("name").(string)
	endpointType := d.Get("type").(string)
	fullEndpointType := fmt.Sprintf("Microsoft.Network/TrafficManagerProfiles/%s", endpointType)
	profileName := d.Get("profile_name").(string)
	resGroup := d.Get("resource_group_name").(string)

	params := trafficmanager.Endpoint{
		Name:               &name,
		Type:               &fullEndpointType,
		EndpointProperties: getArmTrafficManagerEndpointProperties(d),
	}

	_, err := client.CreateOrUpdate(resGroup, profileName, endpointType, name, params)
	if err != nil {
		return err
	}

	read, err := client.Get(resGroup, profileName, endpointType, name)
	if err != nil {
		return err
	}
	if read.ID == nil {
		return fmt.Errorf("Cannot read TrafficManager endpoint %s (resource group %s) ID", name, resGroup)
	}

	d.SetId(*read.ID)

	return resourceArmTrafficManagerEndpointRead(d, meta)
}

func resourceArmTrafficManagerEndpointRead(d *schema.ResourceData, meta interface{}) error {
	client := meta.(*ArmClient).trafficManagerEndpointsClient

	id, err := parseAzureResourceID(d.Id())
	if err != nil {
		return err
	}
	resGroup := id.ResourceGroup

	// lookup endpointType in Azure ID path
	var endpointType string
	typeRegex := regexp.MustCompile("azureEndpoints|externalEndpoints|nestedEndpoints")
	for k := range id.Path {
		if typeRegex.MatchString(k) {
			endpointType = k
		}
	}
	profileName := id.Path["trafficManagerProfiles"]

	// endpoint name is keyed by endpoint type in ARM ID
	name := id.Path[endpointType]

	resp, err := client.Get(resGroup, profileName, endpointType, name)
	if err != nil {
		if resp.StatusCode == http.StatusNotFound {
			d.SetId("")
			return nil
		}
		return fmt.Errorf("Error making Read request on TrafficManager Endpoint %s: %s", name, err)
	}

	endpoint := *resp.EndpointProperties

	d.Set("resource_group_name", resGroup)
	d.Set("name", resp.Name)
	d.Set("type", endpointType)
	d.Set("profile_name", profileName)
	d.Set("endpoint_status", endpoint.EndpointStatus)
	d.Set("target_resource_id", endpoint.TargetResourceID)
	d.Set("target", endpoint.Target)
	d.Set("weight", endpoint.Weight)
	d.Set("priority", endpoint.Priority)
	d.Set("endpoint_location", endpoint.EndpointLocation)
	d.Set("endpoint_monitor_status", endpoint.EndpointMonitorStatus)
	d.Set("min_child_endpoints", endpoint.MinChildEndpoints)

	return nil
}

func resourceArmTrafficManagerEndpointDelete(d *schema.ResourceData, meta interface{}) error {
	client := meta.(*ArmClient).trafficManagerEndpointsClient

	id, err := parseAzureResourceID(d.Id())
	if err != nil {
		return err
	}
	resGroup := id.ResourceGroup
	endpointType := d.Get("type").(string)
	profileName := id.Path["trafficManagerProfiles"]

	// endpoint name is keyed by endpoint type in ARM ID
	name := id.Path[endpointType]

	_, err = client.Delete(resGroup, profileName, endpointType, name)

	return err
}

func getArmTrafficManagerEndpointProperties(d *schema.ResourceData) *trafficmanager.EndpointProperties {
	var endpointProps trafficmanager.EndpointProperties

	if targetResID := d.Get("target_resource_id").(string); targetResID != "" {
		endpointProps.TargetResourceID = &targetResID
	}

	if target := d.Get("target").(string); target != "" {
		endpointProps.Target = &target
	}

	if status := d.Get("endpoint_status").(string); status != "" {
		endpointProps.EndpointStatus = &status
	}

	if weight := d.Get("weight").(int); weight != 0 {
		w64 := int64(weight)
		endpointProps.Weight = &w64
	}

	if priority := d.Get("priority").(int); priority != 0 {
		p64 := int64(priority)
		endpointProps.Priority = &p64
	}

	if location := d.Get("endpoint_location").(string); location != "" {
		endpointProps.EndpointLocation = &location
	}

	if minChildEndpoints := d.Get("min_child_endpoints").(int); minChildEndpoints != 0 {
		mci64 := int64(minChildEndpoints)
		endpointProps.MinChildEndpoints = &mci64
	}

	return &endpointProps
}