package userpass

import (
	"fmt"

	"golang.org/x/crypto/bcrypt"

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

func pathUserPassword(b *backend) *framework.Path {
	return &framework.Path{
		Pattern: "users/" + framework.GenericNameRegex("username") + "/password$",
		Fields: map[string]*framework.FieldSchema{
			"username": &framework.FieldSchema{
				Type:        framework.TypeString,
				Description: "Username for this user.",
			},

			"password": &framework.FieldSchema{
				Type:        framework.TypeString,
				Description: "Password for this user.",
			},
		},

		ExistenceCheck: b.userPasswordExistenceCheck,

		Callbacks: map[logical.Operation]framework.OperationFunc{
			logical.UpdateOperation: b.pathUserPasswordUpdate,
		},

		HelpSynopsis:    pathUserPasswordHelpSyn,
		HelpDescription: pathUserPasswordHelpDesc,
	}
}

// By always returning true, this endpoint will be enforced to be invoked only upon UpdateOperation.
// The existence of user will be checked in the operation handler.
func (b *backend) userPasswordExistenceCheck(req *logical.Request, data *framework.FieldData) (bool, error) {
	return true, nil
}

func (b *backend) pathUserPasswordUpdate(
	req *logical.Request, d *framework.FieldData) (*logical.Response, error) {

	username := d.Get("username").(string)

	userEntry, err := b.user(req.Storage, username)
	if err != nil {
		return nil, err
	}
	if userEntry == nil {
		return nil, fmt.Errorf("username does not exist")
	}

	err = b.updateUserPassword(req, d, userEntry)
	if err != nil {
		return nil, err
	}

	return nil, b.setUser(req.Storage, username, userEntry)
}

func (b *backend) updateUserPassword(req *logical.Request, d *framework.FieldData, userEntry *UserEntry) error {
	password := d.Get("password").(string)
	if password == "" {
		return fmt.Errorf("missing password")
	}
	// Generate a hash of the password
	hash, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
	if err != nil {
		return err
	}
	userEntry.PasswordHash = hash
	return nil
}

const pathUserPasswordHelpSyn = `
Reset user's password.
`

const pathUserPasswordHelpDesc = `
This endpoint allows resetting the user's password.
`