package aws

import (
	"fmt"
	"strings"

	"github.com/hashicorp/vault/logical"
	"github.com/hashicorp/vault/logical/framework"
)

func pathSTS(b *backend) *framework.Path {
	return &framework.Path{
		Pattern: "sts/" + framework.GenericNameRegex("name"),
		Fields: map[string]*framework.FieldSchema{
			"name": &framework.FieldSchema{
				Type:        framework.TypeString,
				Description: "Name of the role",
			},
			"ttl": &framework.FieldSchema{
				Type:        framework.TypeDurationSecond,
				Description: "Lifetime of the token in seconds",
				Default:     3600,
			},
		},

		Callbacks: map[logical.Operation]framework.OperationFunc{
			logical.ReadOperation: b.pathSTSRead,
		},

		HelpSynopsis:    pathSTSHelpSyn,
		HelpDescription: pathSTSHelpDesc,
	}
}

func (b *backend) pathSTSRead(
	req *logical.Request, d *framework.FieldData) (*logical.Response, error) {
	policyName := d.Get("name").(string)
	ttl := int64(d.Get("ttl").(int))

	// Read the policy
	policy, err := req.Storage.Get("policy/" + policyName)
	if err != nil {
		return nil, fmt.Errorf("error retrieving role: %s", err)
	}
	if policy == nil {
		return logical.ErrorResponse(fmt.Sprintf(
			"Role '%s' not found", policyName)), nil
	}
	policyValue := string(policy.Value)
	if strings.HasPrefix(policyValue, "arn:") {
		if strings.Contains(policyValue, ":role/") {
			return b.assumeRole(
				req.Storage,
				req.DisplayName, policyName, policyValue,
				ttl,
			)
		} else {
			return logical.ErrorResponse(
					"Can't generate STS credentials for a managed policy; use a role to assume or an inline policy instead"),
				logical.ErrInvalidRequest
		}
	}
	// Use the helper to create the secret
	return b.secretTokenCreate(
		req.Storage,
		req.DisplayName, policyName, policyValue,
		ttl,
	)
}

const pathSTSHelpSyn = `
Generate an access key pair + security token for a specific role.
`

const pathSTSHelpDesc = `
This path will generate a new, never before used key pair + security token for
accessing AWS. The IAM policy used to back this key pair will be
the "name" parameter. For example, if this backend is mounted at "aws",
then "aws/sts/deploy" would generate access keys for the "deploy" role.

Note, these credentials are instantiated using the AWS STS backend.

The access keys will have a lease associated with them. The access keys
can be revoked by using the lease ID.
`