// © Broadcom. All Rights Reserved.
// The term “Broadcom” refers to Broadcom Inc. and/or its subsidiaries.
// SPDX-License-Identifier: Apache-2.0

package vim25

import (
	"context"
	"encoding/json"
	"strings"

	"github.com/vmware/govmomi/vim25/methods"
	"github.com/vmware/govmomi/vim25/soap"
	"github.com/vmware/govmomi/vim25/types"
)

const (
	Namespace = "vim25"
	Version   = "9.0.0.0"
	Path      = "/sdk"
)

var (
	ServiceInstance = types.ManagedObjectReference{
		Type:  "ServiceInstance",
		Value: "ServiceInstance",
	}
)

// Client is a tiny wrapper around the vim25/soap Client that stores session
// specific state (i.e. state that only needs to be retrieved once after the
// client has been created). This means the client can be reused after
// serialization without performing additional requests for initialization.
type Client struct {
	*soap.Client

	ServiceContent types.ServiceContent

	// RoundTripper is a separate field such that the client's implementation of
	// the RoundTripper interface can be wrapped by separate implementations for
	// extra functionality (for example, reauthentication on session timeout).
	RoundTripper soap.RoundTripper
}

// NewClient creates and returns a new client with the ServiceContent field
// filled in.
func NewClient(ctx context.Context, rt soap.RoundTripper) (*Client, error) {
	c := Client{
		RoundTripper: rt,
	}

	// Set client if it happens to be a soap.Client
	if sc, ok := rt.(*soap.Client); ok {
		c.Client = sc

		if c.Namespace == "" {
			c.Namespace = "urn:" + Namespace
		} else if !strings.Contains(c.Namespace, ":") {
			c.Namespace = "urn:" + c.Namespace // ensure valid URI format
		}
		if c.Version == "" {
			c.Version = Version
		}
	}

	var err error
	c.ServiceContent, err = methods.GetServiceContent(ctx, rt)
	if err != nil {
		return nil, err
	}

	return &c, nil
}

// RoundTrip dispatches to the RoundTripper field.
func (c *Client) RoundTrip(ctx context.Context, req, res soap.HasFault) error {
	return c.RoundTripper.RoundTrip(ctx, req, res)
}

type marshaledClient struct {
	SoapClient     *soap.Client
	ServiceContent types.ServiceContent
}

func (c *Client) MarshalJSON() ([]byte, error) {
	m := marshaledClient{
		SoapClient:     c.Client,
		ServiceContent: c.ServiceContent,
	}

	return json.Marshal(m)
}

func (c *Client) UnmarshalJSON(b []byte) error {
	var m marshaledClient

	err := json.Unmarshal(b, &m)
	if err != nil {
		return err
	}

	*c = Client{
		Client:         m.SoapClient,
		ServiceContent: m.ServiceContent,
		RoundTripper:   m.SoapClient,
	}

	return nil
}

// Valid returns whether or not the client is valid and ready for use.
// This should be called after unmarshalling the client.
func (c *Client) Valid() bool {
	if c == nil {
		return false
	}

	if c.Client == nil {
		return false
	}

	// Use arbitrary pointer field in the service content.
	// Doesn't matter which one, as long as it is populated by default.
	if c.ServiceContent.SessionManager == nil {
		return false
	}

	return true
}

// Path returns vim25.Path (see cache.Client)
func (c *Client) Path() string {
	return Path
}

// IsVC returns true if we are connected to a vCenter
func (c *Client) IsVC() bool {
	return c.ServiceContent.About.ApiType == "VirtualCenter"
}