package azurerm

import (
	"fmt"
	"net/http"
	"strings"

	"github.com/Azure/azure-sdk-for-go/arm/network"
	"github.com/hashicorp/errwrap"
	"github.com/hashicorp/terraform/helper/resource"
)

func resourceGroupAndLBNameFromId(loadBalancerId string) (string, string, error) {
	id, err := parseAzureResourceID(loadBalancerId)
	if err != nil {
		return "", "", err
	}
	name := id.Path["loadBalancers"]
	resGroup := id.ResourceGroup

	return resGroup, name, nil
}

func retrieveLoadBalancerById(loadBalancerId string, meta interface{}) (*network.LoadBalancer, bool, error) {
	loadBalancerClient := meta.(*ArmClient).loadBalancerClient

	resGroup, name, err := resourceGroupAndLBNameFromId(loadBalancerId)
	if err != nil {
		return nil, false, errwrap.Wrapf("Error Getting LoadBalancer Name and Group: {{err}}", err)
	}

	resp, err := loadBalancerClient.Get(resGroup, name, "")
	if err != nil {
		if resp.StatusCode == http.StatusNotFound {
			return nil, false, nil
		}
		return nil, false, fmt.Errorf("Error making Read request on Azure LoadBalancer %s: %s", name, err)
	}

	return &resp, true, nil
}

func findLoadBalancerBackEndAddressPoolByName(lb *network.LoadBalancer, name string) (*network.BackendAddressPool, int, bool) {
	if lb == nil || lb.Properties == nil || lb.Properties.BackendAddressPools == nil {
		return nil, -1, false
	}

	for i, apc := range *lb.Properties.BackendAddressPools {
		if apc.Name != nil && *apc.Name == name {
			return &apc, i, true
		}
	}

	return nil, -1, false
}

func findLoadBalancerFrontEndIpConfigurationByName(lb *network.LoadBalancer, name string) (*network.FrontendIPConfiguration, int, bool) {
	if lb == nil || lb.Properties == nil || lb.Properties.FrontendIPConfigurations == nil {
		return nil, -1, false
	}

	for i, feip := range *lb.Properties.FrontendIPConfigurations {
		if feip.Name != nil && *feip.Name == name {
			return &feip, i, true
		}
	}

	return nil, -1, false
}

func findLoadBalancerRuleByName(lb *network.LoadBalancer, name string) (*network.LoadBalancingRule, int, bool) {
	if lb == nil || lb.Properties == nil || lb.Properties.LoadBalancingRules == nil {
		return nil, -1, false
	}

	for i, lbr := range *lb.Properties.LoadBalancingRules {
		if lbr.Name != nil && *lbr.Name == name {
			return &lbr, i, true
		}
	}

	return nil, -1, false
}

func findLoadBalancerNatRuleByName(lb *network.LoadBalancer, name string) (*network.InboundNatRule, int, bool) {
	if lb == nil || lb.Properties == nil || lb.Properties.InboundNatRules == nil {
		return nil, -1, false
	}

	for i, nr := range *lb.Properties.InboundNatRules {
		if nr.Name != nil && *nr.Name == name {
			return &nr, i, true
		}
	}

	return nil, -1, false
}

func findLoadBalancerNatPoolByName(lb *network.LoadBalancer, name string) (*network.InboundNatPool, int, bool) {
	if lb == nil || lb.Properties == nil || lb.Properties.InboundNatPools == nil {
		return nil, -1, false
	}

	for i, np := range *lb.Properties.InboundNatPools {
		if np.Name != nil && *np.Name == name {
			return &np, i, true
		}
	}

	return nil, -1, false
}

func findLoadBalancerProbeByName(lb *network.LoadBalancer, name string) (*network.Probe, int, bool) {
	if lb == nil || lb.Properties == nil || lb.Properties.Probes == nil {
		return nil, -1, false
	}

	for i, p := range *lb.Properties.Probes {
		if p.Name != nil && *p.Name == name {
			return &p, i, true
		}
	}

	return nil, -1, false
}

func loadbalancerStateRefreshFunc(client *ArmClient, resourceGroupName string, loadbalancer string) resource.StateRefreshFunc {
	return func() (interface{}, string, error) {
		res, err := client.loadBalancerClient.Get(resourceGroupName, loadbalancer, "")
		if err != nil {
			return nil, "", fmt.Errorf("Error issuing read request in loadbalancerStateRefreshFunc to Azure ARM for LoadBalancer '%s' (RG: '%s'): %s", loadbalancer, resourceGroupName, err)
		}

		return res, *res.Properties.ProvisioningState, nil
	}
}

func validateLoadBalancerPrivateIpAddressAllocation(v interface{}, k string) (ws []string, errors []error) {
	value := strings.ToLower(v.(string))
	if value != "static" && value != "dynamic" {
		errors = append(errors, fmt.Errorf("LoadBalancer Allocations can only be Static or Dynamic"))
	}
	return
}