// Copyright 2024 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// Code generated by protoc-gen-go_gapic. DO NOT EDIT.

package discoveryengine

import (
	"bytes"
	"context"
	"fmt"
	"log/slog"
	"math"
	"net/http"
	"net/url"
	"time"

	discoveryenginepb "cloud.google.com/go/discoveryengine/apiv1alpha/discoveryenginepb"
	longrunningpb "cloud.google.com/go/longrunning/autogen/longrunningpb"
	gax "github.com/googleapis/gax-go/v2"
	"google.golang.org/api/iterator"
	"google.golang.org/api/option"
	"google.golang.org/api/option/internaloption"
	gtransport "google.golang.org/api/transport/grpc"
	httptransport "google.golang.org/api/transport/http"
	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/protobuf/encoding/protojson"
	"google.golang.org/protobuf/proto"
)

var newConversationalSearchClientHook clientHook

// ConversationalSearchCallOptions contains the retry settings for each method of ConversationalSearchClient.
type ConversationalSearchCallOptions struct {
	ConverseConversation []gax.CallOption
	CreateConversation   []gax.CallOption
	DeleteConversation   []gax.CallOption
	UpdateConversation   []gax.CallOption
	GetConversation      []gax.CallOption
	ListConversations    []gax.CallOption
	AnswerQuery          []gax.CallOption
	GetAnswer            []gax.CallOption
	CreateSession        []gax.CallOption
	DeleteSession        []gax.CallOption
	UpdateSession        []gax.CallOption
	GetSession           []gax.CallOption
	ListSessions         []gax.CallOption
	CancelOperation      []gax.CallOption
	GetOperation         []gax.CallOption
	ListOperations       []gax.CallOption
}

func defaultConversationalSearchGRPCClientOptions() []option.ClientOption {
	return []option.ClientOption{
		internaloption.WithDefaultEndpoint("discoveryengine.googleapis.com:443"),
		internaloption.WithDefaultEndpointTemplate("discoveryengine.UNIVERSE_DOMAIN:443"),
		internaloption.WithDefaultMTLSEndpoint("discoveryengine.mtls.googleapis.com:443"),
		internaloption.WithDefaultUniverseDomain("googleapis.com"),
		internaloption.WithDefaultAudience("https://discoveryengine.googleapis.com/"),
		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
		internaloption.EnableJwtWithScope(),
		internaloption.EnableNewAuthLibrary(),
		option.WithGRPCDialOption(grpc.WithDefaultCallOptions(
			grpc.MaxCallRecvMsgSize(math.MaxInt32))),
	}
}

func defaultConversationalSearchCallOptions() *ConversationalSearchCallOptions {
	return &ConversationalSearchCallOptions{
		ConverseConversation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		CreateConversation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		DeleteConversation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		UpdateConversation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		GetConversation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		ListConversations: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		AnswerQuery: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		GetAnswer: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		CreateSession: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		DeleteSession: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		UpdateSession: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		GetSession: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		ListSessions: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		CancelOperation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		GetOperation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		ListOperations: []gax.CallOption{
			gax.WithTimeout(300000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        30000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
	}
}

func defaultConversationalSearchRESTCallOptions() *ConversationalSearchCallOptions {
	return &ConversationalSearchCallOptions{
		ConverseConversation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		CreateConversation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		DeleteConversation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		UpdateConversation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		GetConversation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		ListConversations: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		AnswerQuery: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		GetAnswer: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		CreateSession: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		DeleteSession: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		UpdateSession: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		GetSession: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		ListSessions: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		CancelOperation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		GetOperation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		ListOperations: []gax.CallOption{
			gax.WithTimeout(300000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        30000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
	}
}

// internalConversationalSearchClient is an interface that defines the methods available from Discovery Engine API.
type internalConversationalSearchClient interface {
	Close() error
	setGoogleClientInfo(...string)
	Connection() *grpc.ClientConn
	ConverseConversation(context.Context, *discoveryenginepb.ConverseConversationRequest, ...gax.CallOption) (*discoveryenginepb.ConverseConversationResponse, error)
	CreateConversation(context.Context, *discoveryenginepb.CreateConversationRequest, ...gax.CallOption) (*discoveryenginepb.Conversation, error)
	DeleteConversation(context.Context, *discoveryenginepb.DeleteConversationRequest, ...gax.CallOption) error
	UpdateConversation(context.Context, *discoveryenginepb.UpdateConversationRequest, ...gax.CallOption) (*discoveryenginepb.Conversation, error)
	GetConversation(context.Context, *discoveryenginepb.GetConversationRequest, ...gax.CallOption) (*discoveryenginepb.Conversation, error)
	ListConversations(context.Context, *discoveryenginepb.ListConversationsRequest, ...gax.CallOption) *ConversationIterator
	AnswerQuery(context.Context, *discoveryenginepb.AnswerQueryRequest, ...gax.CallOption) (*discoveryenginepb.AnswerQueryResponse, error)
	GetAnswer(context.Context, *discoveryenginepb.GetAnswerRequest, ...gax.CallOption) (*discoveryenginepb.Answer, error)
	CreateSession(context.Context, *discoveryenginepb.CreateSessionRequest, ...gax.CallOption) (*discoveryenginepb.Session, error)
	DeleteSession(context.Context, *discoveryenginepb.DeleteSessionRequest, ...gax.CallOption) error
	UpdateSession(context.Context, *discoveryenginepb.UpdateSessionRequest, ...gax.CallOption) (*discoveryenginepb.Session, error)
	GetSession(context.Context, *discoveryenginepb.GetSessionRequest, ...gax.CallOption) (*discoveryenginepb.Session, error)
	ListSessions(context.Context, *discoveryenginepb.ListSessionsRequest, ...gax.CallOption) *SessionIterator
	CancelOperation(context.Context, *longrunningpb.CancelOperationRequest, ...gax.CallOption) error
	GetOperation(context.Context, *longrunningpb.GetOperationRequest, ...gax.CallOption) (*longrunningpb.Operation, error)
	ListOperations(context.Context, *longrunningpb.ListOperationsRequest, ...gax.CallOption) *OperationIterator
}

// ConversationalSearchClient is a client for interacting with Discovery Engine API.
// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
//
// Service for conversational search.
type ConversationalSearchClient struct {
	// The internal transport-dependent client.
	internalClient internalConversationalSearchClient

	// The call options for this service.
	CallOptions *ConversationalSearchCallOptions
}

// Wrapper methods routed to the internal client.

// Close closes the connection to the API service. The user should invoke this when
// the client is no longer required.
func (c *ConversationalSearchClient) Close() error {
	return c.internalClient.Close()
}

// setGoogleClientInfo sets the name and version of the application in
// the `x-goog-api-client` header passed on each request. Intended for
// use by Google-written clients.
func (c *ConversationalSearchClient) setGoogleClientInfo(keyval ...string) {
	c.internalClient.setGoogleClientInfo(keyval...)
}

// Connection returns a connection to the API service.
//
// Deprecated: Connections are now pooled so this method does not always
// return the same resource.
func (c *ConversationalSearchClient) Connection() *grpc.ClientConn {
	return c.internalClient.Connection()
}

// ConverseConversation converses a conversation.
func (c *ConversationalSearchClient) ConverseConversation(ctx context.Context, req *discoveryenginepb.ConverseConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.ConverseConversationResponse, error) {
	return c.internalClient.ConverseConversation(ctx, req, opts...)
}

// CreateConversation creates a Conversation.
//
// If the Conversation to
// create already exists, an ALREADY_EXISTS error is returned.
func (c *ConversationalSearchClient) CreateConversation(ctx context.Context, req *discoveryenginepb.CreateConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.Conversation, error) {
	return c.internalClient.CreateConversation(ctx, req, opts...)
}

// DeleteConversation deletes a Conversation.
//
// If the Conversation to
// delete does not exist, a NOT_FOUND error is returned.
func (c *ConversationalSearchClient) DeleteConversation(ctx context.Context, req *discoveryenginepb.DeleteConversationRequest, opts ...gax.CallOption) error {
	return c.internalClient.DeleteConversation(ctx, req, opts...)
}

// UpdateConversation updates a Conversation.
//
// Conversation action
// type cannot be changed. If the
// Conversation to update
// does not exist, a NOT_FOUND error is returned.
func (c *ConversationalSearchClient) UpdateConversation(ctx context.Context, req *discoveryenginepb.UpdateConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.Conversation, error) {
	return c.internalClient.UpdateConversation(ctx, req, opts...)
}

// GetConversation gets a Conversation.
func (c *ConversationalSearchClient) GetConversation(ctx context.Context, req *discoveryenginepb.GetConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.Conversation, error) {
	return c.internalClient.GetConversation(ctx, req, opts...)
}

// ListConversations lists all Conversations by their parent
// DataStore.
func (c *ConversationalSearchClient) ListConversations(ctx context.Context, req *discoveryenginepb.ListConversationsRequest, opts ...gax.CallOption) *ConversationIterator {
	return c.internalClient.ListConversations(ctx, req, opts...)
}

// AnswerQuery answer query method.
func (c *ConversationalSearchClient) AnswerQuery(ctx context.Context, req *discoveryenginepb.AnswerQueryRequest, opts ...gax.CallOption) (*discoveryenginepb.AnswerQueryResponse, error) {
	return c.internalClient.AnswerQuery(ctx, req, opts...)
}

// GetAnswer gets a Answer.
func (c *ConversationalSearchClient) GetAnswer(ctx context.Context, req *discoveryenginepb.GetAnswerRequest, opts ...gax.CallOption) (*discoveryenginepb.Answer, error) {
	return c.internalClient.GetAnswer(ctx, req, opts...)
}

// CreateSession creates a Session.
//
// If the Session to create
// already exists, an ALREADY_EXISTS error is returned.
func (c *ConversationalSearchClient) CreateSession(ctx context.Context, req *discoveryenginepb.CreateSessionRequest, opts ...gax.CallOption) (*discoveryenginepb.Session, error) {
	return c.internalClient.CreateSession(ctx, req, opts...)
}

// DeleteSession deletes a Session.
//
// If the Session to delete
// does not exist, a NOT_FOUND error is returned.
func (c *ConversationalSearchClient) DeleteSession(ctx context.Context, req *discoveryenginepb.DeleteSessionRequest, opts ...gax.CallOption) error {
	return c.internalClient.DeleteSession(ctx, req, opts...)
}

// UpdateSession updates a Session.
//
// Session action type cannot
// be changed. If the Session
// to update does not exist, a NOT_FOUND error is returned.
func (c *ConversationalSearchClient) UpdateSession(ctx context.Context, req *discoveryenginepb.UpdateSessionRequest, opts ...gax.CallOption) (*discoveryenginepb.Session, error) {
	return c.internalClient.UpdateSession(ctx, req, opts...)
}

// GetSession gets a Session.
func (c *ConversationalSearchClient) GetSession(ctx context.Context, req *discoveryenginepb.GetSessionRequest, opts ...gax.CallOption) (*discoveryenginepb.Session, error) {
	return c.internalClient.GetSession(ctx, req, opts...)
}

// ListSessions lists all Sessions by their parent
// DataStore.
func (c *ConversationalSearchClient) ListSessions(ctx context.Context, req *discoveryenginepb.ListSessionsRequest, opts ...gax.CallOption) *SessionIterator {
	return c.internalClient.ListSessions(ctx, req, opts...)
}

// CancelOperation is a utility method from google.longrunning.Operations.
func (c *ConversationalSearchClient) CancelOperation(ctx context.Context, req *longrunningpb.CancelOperationRequest, opts ...gax.CallOption) error {
	return c.internalClient.CancelOperation(ctx, req, opts...)
}

// GetOperation is a utility method from google.longrunning.Operations.
func (c *ConversationalSearchClient) GetOperation(ctx context.Context, req *longrunningpb.GetOperationRequest, opts ...gax.CallOption) (*longrunningpb.Operation, error) {
	return c.internalClient.GetOperation(ctx, req, opts...)
}

// ListOperations is a utility method from google.longrunning.Operations.
func (c *ConversationalSearchClient) ListOperations(ctx context.Context, req *longrunningpb.ListOperationsRequest, opts ...gax.CallOption) *OperationIterator {
	return c.internalClient.ListOperations(ctx, req, opts...)
}

// conversationalSearchGRPCClient is a client for interacting with Discovery Engine API over gRPC transport.
//
// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
type conversationalSearchGRPCClient struct {
	// Connection pool of gRPC connections to the service.
	connPool gtransport.ConnPool

	// Points back to the CallOptions field of the containing ConversationalSearchClient
	CallOptions **ConversationalSearchCallOptions

	// The gRPC API client.
	conversationalSearchClient discoveryenginepb.ConversationalSearchServiceClient

	operationsClient longrunningpb.OperationsClient

	// The x-goog-* metadata to be sent with each request.
	xGoogHeaders []string

	logger *slog.Logger
}

// NewConversationalSearchClient creates a new conversational search service client based on gRPC.
// The returned client must be Closed when it is done being used to clean up its underlying connections.
//
// Service for conversational search.
func NewConversationalSearchClient(ctx context.Context, opts ...option.ClientOption) (*ConversationalSearchClient, error) {
	clientOpts := defaultConversationalSearchGRPCClientOptions()
	if newConversationalSearchClientHook != nil {
		hookOpts, err := newConversationalSearchClientHook(ctx, clientHookParams{})
		if err != nil {
			return nil, err
		}
		clientOpts = append(clientOpts, hookOpts...)
	}

	connPool, err := gtransport.DialPool(ctx, append(clientOpts, opts...)...)
	if err != nil {
		return nil, err
	}
	client := ConversationalSearchClient{CallOptions: defaultConversationalSearchCallOptions()}

	c := &conversationalSearchGRPCClient{
		connPool:                   connPool,
		conversationalSearchClient: discoveryenginepb.NewConversationalSearchServiceClient(connPool),
		CallOptions:                &client.CallOptions,
		logger:                     internaloption.GetLogger(opts),
		operationsClient:           longrunningpb.NewOperationsClient(connPool),
	}
	c.setGoogleClientInfo()

	client.internalClient = c

	return &client, nil
}

// Connection returns a connection to the API service.
//
// Deprecated: Connections are now pooled so this method does not always
// return the same resource.
func (c *conversationalSearchGRPCClient) Connection() *grpc.ClientConn {
	return c.connPool.Conn()
}

// setGoogleClientInfo sets the name and version of the application in
// the `x-goog-api-client` header passed on each request. Intended for
// use by Google-written clients.
func (c *conversationalSearchGRPCClient) setGoogleClientInfo(keyval ...string) {
	kv := append([]string{"gl-go", gax.GoVersion}, keyval...)
	kv = append(kv, "gapic", getVersionClient(), "gax", gax.Version, "grpc", grpc.Version)
	c.xGoogHeaders = []string{
		"x-goog-api-client", gax.XGoogHeader(kv...),
	}
}

// Close closes the connection to the API service. The user should invoke this when
// the client is no longer required.
func (c *conversationalSearchGRPCClient) Close() error {
	return c.connPool.Close()
}

// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
type conversationalSearchRESTClient struct {
	// The http endpoint to connect to.
	endpoint string

	// The http client.
	httpClient *http.Client

	// The x-goog-* headers to be sent with each request.
	xGoogHeaders []string

	// Points back to the CallOptions field of the containing ConversationalSearchClient
	CallOptions **ConversationalSearchCallOptions

	logger *slog.Logger
}

// NewConversationalSearchRESTClient creates a new conversational search service rest client.
//
// Service for conversational search.
func NewConversationalSearchRESTClient(ctx context.Context, opts ...option.ClientOption) (*ConversationalSearchClient, error) {
	clientOpts := append(defaultConversationalSearchRESTClientOptions(), opts...)
	httpClient, endpoint, err := httptransport.NewClient(ctx, clientOpts...)
	if err != nil {
		return nil, err
	}

	callOpts := defaultConversationalSearchRESTCallOptions()
	c := &conversationalSearchRESTClient{
		endpoint:    endpoint,
		httpClient:  httpClient,
		CallOptions: &callOpts,
		logger:      internaloption.GetLogger(opts),
	}
	c.setGoogleClientInfo()

	return &ConversationalSearchClient{internalClient: c, CallOptions: callOpts}, nil
}

func defaultConversationalSearchRESTClientOptions() []option.ClientOption {
	return []option.ClientOption{
		internaloption.WithDefaultEndpoint("https://discoveryengine.googleapis.com"),
		internaloption.WithDefaultEndpointTemplate("https://discoveryengine.UNIVERSE_DOMAIN"),
		internaloption.WithDefaultMTLSEndpoint("https://discoveryengine.mtls.googleapis.com"),
		internaloption.WithDefaultUniverseDomain("googleapis.com"),
		internaloption.WithDefaultAudience("https://discoveryengine.googleapis.com/"),
		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
		internaloption.EnableNewAuthLibrary(),
	}
}

// setGoogleClientInfo sets the name and version of the application in
// the `x-goog-api-client` header passed on each request. Intended for
// use by Google-written clients.
func (c *conversationalSearchRESTClient) setGoogleClientInfo(keyval ...string) {
	kv := append([]string{"gl-go", gax.GoVersion}, keyval...)
	kv = append(kv, "gapic", getVersionClient(), "gax", gax.Version, "rest", "UNKNOWN")
	c.xGoogHeaders = []string{
		"x-goog-api-client", gax.XGoogHeader(kv...),
	}
}

// Close closes the connection to the API service. The user should invoke this when
// the client is no longer required.
func (c *conversationalSearchRESTClient) Close() error {
	// Replace httpClient with nil to force cleanup.
	c.httpClient = nil
	return nil
}

// Connection returns a connection to the API service.
//
// Deprecated: This method always returns nil.
func (c *conversationalSearchRESTClient) Connection() *grpc.ClientConn {
	return nil
}
func (c *conversationalSearchGRPCClient) ConverseConversation(ctx context.Context, req *discoveryenginepb.ConverseConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.ConverseConversationResponse, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).ConverseConversation[0:len((*c.CallOptions).ConverseConversation):len((*c.CallOptions).ConverseConversation)], opts...)
	var resp *discoveryenginepb.ConverseConversationResponse
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.conversationalSearchClient.ConverseConversation, req, settings.GRPC, c.logger, "ConverseConversation")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *conversationalSearchGRPCClient) CreateConversation(ctx context.Context, req *discoveryenginepb.CreateConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.Conversation, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "parent", url.QueryEscape(req.GetParent()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).CreateConversation[0:len((*c.CallOptions).CreateConversation):len((*c.CallOptions).CreateConversation)], opts...)
	var resp *discoveryenginepb.Conversation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.conversationalSearchClient.CreateConversation, req, settings.GRPC, c.logger, "CreateConversation")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *conversationalSearchGRPCClient) DeleteConversation(ctx context.Context, req *discoveryenginepb.DeleteConversationRequest, opts ...gax.CallOption) error {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).DeleteConversation[0:len((*c.CallOptions).DeleteConversation):len((*c.CallOptions).DeleteConversation)], opts...)
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		_, err = executeRPC(ctx, c.conversationalSearchClient.DeleteConversation, req, settings.GRPC, c.logger, "DeleteConversation")
		return err
	}, opts...)
	return err
}

func (c *conversationalSearchGRPCClient) UpdateConversation(ctx context.Context, req *discoveryenginepb.UpdateConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.Conversation, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "conversation.name", url.QueryEscape(req.GetConversation().GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).UpdateConversation[0:len((*c.CallOptions).UpdateConversation):len((*c.CallOptions).UpdateConversation)], opts...)
	var resp *discoveryenginepb.Conversation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.conversationalSearchClient.UpdateConversation, req, settings.GRPC, c.logger, "UpdateConversation")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *conversationalSearchGRPCClient) GetConversation(ctx context.Context, req *discoveryenginepb.GetConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.Conversation, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).GetConversation[0:len((*c.CallOptions).GetConversation):len((*c.CallOptions).GetConversation)], opts...)
	var resp *discoveryenginepb.Conversation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.conversationalSearchClient.GetConversation, req, settings.GRPC, c.logger, "GetConversation")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *conversationalSearchGRPCClient) ListConversations(ctx context.Context, req *discoveryenginepb.ListConversationsRequest, opts ...gax.CallOption) *ConversationIterator {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "parent", url.QueryEscape(req.GetParent()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).ListConversations[0:len((*c.CallOptions).ListConversations):len((*c.CallOptions).ListConversations)], opts...)
	it := &ConversationIterator{}
	req = proto.Clone(req).(*discoveryenginepb.ListConversationsRequest)
	it.InternalFetch = func(pageSize int, pageToken string) ([]*discoveryenginepb.Conversation, string, error) {
		resp := &discoveryenginepb.ListConversationsResponse{}
		if pageToken != "" {
			req.PageToken = pageToken
		}
		if pageSize > math.MaxInt32 {
			req.PageSize = math.MaxInt32
		} else if pageSize != 0 {
			req.PageSize = int32(pageSize)
		}
		err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			var err error
			resp, err = executeRPC(ctx, c.conversationalSearchClient.ListConversations, req, settings.GRPC, c.logger, "ListConversations")
			return err
		}, opts...)
		if err != nil {
			return nil, "", err
		}

		it.Response = resp
		return resp.GetConversations(), resp.GetNextPageToken(), nil
	}
	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetPageSize())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

func (c *conversationalSearchGRPCClient) AnswerQuery(ctx context.Context, req *discoveryenginepb.AnswerQueryRequest, opts ...gax.CallOption) (*discoveryenginepb.AnswerQueryResponse, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "serving_config", url.QueryEscape(req.GetServingConfig()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).AnswerQuery[0:len((*c.CallOptions).AnswerQuery):len((*c.CallOptions).AnswerQuery)], opts...)
	var resp *discoveryenginepb.AnswerQueryResponse
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.conversationalSearchClient.AnswerQuery, req, settings.GRPC, c.logger, "AnswerQuery")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *conversationalSearchGRPCClient) GetAnswer(ctx context.Context, req *discoveryenginepb.GetAnswerRequest, opts ...gax.CallOption) (*discoveryenginepb.Answer, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).GetAnswer[0:len((*c.CallOptions).GetAnswer):len((*c.CallOptions).GetAnswer)], opts...)
	var resp *discoveryenginepb.Answer
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.conversationalSearchClient.GetAnswer, req, settings.GRPC, c.logger, "GetAnswer")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *conversationalSearchGRPCClient) CreateSession(ctx context.Context, req *discoveryenginepb.CreateSessionRequest, opts ...gax.CallOption) (*discoveryenginepb.Session, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "parent", url.QueryEscape(req.GetParent()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).CreateSession[0:len((*c.CallOptions).CreateSession):len((*c.CallOptions).CreateSession)], opts...)
	var resp *discoveryenginepb.Session
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.conversationalSearchClient.CreateSession, req, settings.GRPC, c.logger, "CreateSession")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *conversationalSearchGRPCClient) DeleteSession(ctx context.Context, req *discoveryenginepb.DeleteSessionRequest, opts ...gax.CallOption) error {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).DeleteSession[0:len((*c.CallOptions).DeleteSession):len((*c.CallOptions).DeleteSession)], opts...)
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		_, err = executeRPC(ctx, c.conversationalSearchClient.DeleteSession, req, settings.GRPC, c.logger, "DeleteSession")
		return err
	}, opts...)
	return err
}

func (c *conversationalSearchGRPCClient) UpdateSession(ctx context.Context, req *discoveryenginepb.UpdateSessionRequest, opts ...gax.CallOption) (*discoveryenginepb.Session, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "session.name", url.QueryEscape(req.GetSession().GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).UpdateSession[0:len((*c.CallOptions).UpdateSession):len((*c.CallOptions).UpdateSession)], opts...)
	var resp *discoveryenginepb.Session
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.conversationalSearchClient.UpdateSession, req, settings.GRPC, c.logger, "UpdateSession")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *conversationalSearchGRPCClient) GetSession(ctx context.Context, req *discoveryenginepb.GetSessionRequest, opts ...gax.CallOption) (*discoveryenginepb.Session, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).GetSession[0:len((*c.CallOptions).GetSession):len((*c.CallOptions).GetSession)], opts...)
	var resp *discoveryenginepb.Session
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.conversationalSearchClient.GetSession, req, settings.GRPC, c.logger, "GetSession")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *conversationalSearchGRPCClient) ListSessions(ctx context.Context, req *discoveryenginepb.ListSessionsRequest, opts ...gax.CallOption) *SessionIterator {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "parent", url.QueryEscape(req.GetParent()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).ListSessions[0:len((*c.CallOptions).ListSessions):len((*c.CallOptions).ListSessions)], opts...)
	it := &SessionIterator{}
	req = proto.Clone(req).(*discoveryenginepb.ListSessionsRequest)
	it.InternalFetch = func(pageSize int, pageToken string) ([]*discoveryenginepb.Session, string, error) {
		resp := &discoveryenginepb.ListSessionsResponse{}
		if pageToken != "" {
			req.PageToken = pageToken
		}
		if pageSize > math.MaxInt32 {
			req.PageSize = math.MaxInt32
		} else if pageSize != 0 {
			req.PageSize = int32(pageSize)
		}
		err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			var err error
			resp, err = executeRPC(ctx, c.conversationalSearchClient.ListSessions, req, settings.GRPC, c.logger, "ListSessions")
			return err
		}, opts...)
		if err != nil {
			return nil, "", err
		}

		it.Response = resp
		return resp.GetSessions(), resp.GetNextPageToken(), nil
	}
	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetPageSize())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

func (c *conversationalSearchGRPCClient) CancelOperation(ctx context.Context, req *longrunningpb.CancelOperationRequest, opts ...gax.CallOption) error {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).CancelOperation[0:len((*c.CallOptions).CancelOperation):len((*c.CallOptions).CancelOperation)], opts...)
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		_, err = executeRPC(ctx, c.operationsClient.CancelOperation, req, settings.GRPC, c.logger, "CancelOperation")
		return err
	}, opts...)
	return err
}

func (c *conversationalSearchGRPCClient) GetOperation(ctx context.Context, req *longrunningpb.GetOperationRequest, opts ...gax.CallOption) (*longrunningpb.Operation, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).GetOperation[0:len((*c.CallOptions).GetOperation):len((*c.CallOptions).GetOperation)], opts...)
	var resp *longrunningpb.Operation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.operationsClient.GetOperation, req, settings.GRPC, c.logger, "GetOperation")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *conversationalSearchGRPCClient) ListOperations(ctx context.Context, req *longrunningpb.ListOperationsRequest, opts ...gax.CallOption) *OperationIterator {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	opts = append((*c.CallOptions).ListOperations[0:len((*c.CallOptions).ListOperations):len((*c.CallOptions).ListOperations)], opts...)
	it := &OperationIterator{}
	req = proto.Clone(req).(*longrunningpb.ListOperationsRequest)
	it.InternalFetch = func(pageSize int, pageToken string) ([]*longrunningpb.Operation, string, error) {
		resp := &longrunningpb.ListOperationsResponse{}
		if pageToken != "" {
			req.PageToken = pageToken
		}
		if pageSize > math.MaxInt32 {
			req.PageSize = math.MaxInt32
		} else if pageSize != 0 {
			req.PageSize = int32(pageSize)
		}
		err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			var err error
			resp, err = executeRPC(ctx, c.operationsClient.ListOperations, req, settings.GRPC, c.logger, "ListOperations")
			return err
		}, opts...)
		if err != nil {
			return nil, "", err
		}

		it.Response = resp
		return resp.GetOperations(), resp.GetNextPageToken(), nil
	}
	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetPageSize())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

// ConverseConversation converses a conversation.
func (c *conversationalSearchRESTClient) ConverseConversation(ctx context.Context, req *discoveryenginepb.ConverseConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.ConverseConversationResponse, error) {
	m := protojson.MarshalOptions{AllowPartial: true, UseEnumNumbers: true}
	jsonReq, err := m.Marshal(req)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v:converse", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	opts = append((*c.CallOptions).ConverseConversation[0:len((*c.CallOptions).ConverseConversation):len((*c.CallOptions).ConverseConversation)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &discoveryenginepb.ConverseConversationResponse{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, jsonReq, "ConverseConversation")
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// CreateConversation creates a Conversation.
//
// If the Conversation to
// create already exists, an ALREADY_EXISTS error is returned.
func (c *conversationalSearchRESTClient) CreateConversation(ctx context.Context, req *discoveryenginepb.CreateConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.Conversation, error) {
	m := protojson.MarshalOptions{AllowPartial: true, UseEnumNumbers: true}
	body := req.GetConversation()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v/conversations", req.GetParent())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "parent", url.QueryEscape(req.GetParent()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	opts = append((*c.CallOptions).CreateConversation[0:len((*c.CallOptions).CreateConversation):len((*c.CallOptions).CreateConversation)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &discoveryenginepb.Conversation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, jsonReq, "CreateConversation")
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// DeleteConversation deletes a Conversation.
//
// If the Conversation to
// delete does not exist, a NOT_FOUND error is returned.
func (c *conversationalSearchRESTClient) DeleteConversation(ctx context.Context, req *discoveryenginepb.DeleteConversationRequest, opts ...gax.CallOption) error {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	return gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("DELETE", baseUrl.String(), nil)
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		_, err = executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "DeleteConversation")
		return err
	}, opts...)
}

// UpdateConversation updates a Conversation.
//
// Conversation action
// type cannot be changed. If the
// Conversation to update
// does not exist, a NOT_FOUND error is returned.
func (c *conversationalSearchRESTClient) UpdateConversation(ctx context.Context, req *discoveryenginepb.UpdateConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.Conversation, error) {
	m := protojson.MarshalOptions{AllowPartial: true, UseEnumNumbers: true}
	body := req.GetConversation()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v", req.GetConversation().GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")
	if req.GetUpdateMask() != nil {
		field, err := protojson.Marshal(req.GetUpdateMask())
		if err != nil {
			return nil, err
		}
		params.Add("updateMask", string(field[1:len(field)-1]))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "conversation.name", url.QueryEscape(req.GetConversation().GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	opts = append((*c.CallOptions).UpdateConversation[0:len((*c.CallOptions).UpdateConversation):len((*c.CallOptions).UpdateConversation)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &discoveryenginepb.Conversation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("PATCH", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, jsonReq, "UpdateConversation")
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// GetConversation gets a Conversation.
func (c *conversationalSearchRESTClient) GetConversation(ctx context.Context, req *discoveryenginepb.GetConversationRequest, opts ...gax.CallOption) (*discoveryenginepb.Conversation, error) {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	opts = append((*c.CallOptions).GetConversation[0:len((*c.CallOptions).GetConversation):len((*c.CallOptions).GetConversation)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &discoveryenginepb.Conversation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "GetConversation")
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// ListConversations lists all Conversations by their parent
// DataStore.
func (c *conversationalSearchRESTClient) ListConversations(ctx context.Context, req *discoveryenginepb.ListConversationsRequest, opts ...gax.CallOption) *ConversationIterator {
	it := &ConversationIterator{}
	req = proto.Clone(req).(*discoveryenginepb.ListConversationsRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*discoveryenginepb.Conversation, string, error) {
		resp := &discoveryenginepb.ListConversationsResponse{}
		if pageToken != "" {
			req.PageToken = pageToken
		}
		if pageSize > math.MaxInt32 {
			req.PageSize = math.MaxInt32
		} else if pageSize != 0 {
			req.PageSize = int32(pageSize)
		}
		baseUrl, err := url.Parse(c.endpoint)
		if err != nil {
			return nil, "", err
		}
		baseUrl.Path += fmt.Sprintf("/v1alpha/%v/conversations", req.GetParent())

		params := url.Values{}
		params.Add("$alt", "json;enum-encoding=int")
		if req.GetFilter() != "" {
			params.Add("filter", fmt.Sprintf("%v", req.GetFilter()))
		}
		if req.GetOrderBy() != "" {
			params.Add("orderBy", fmt.Sprintf("%v", req.GetOrderBy()))
		}
		if req.GetPageSize() != 0 {
			params.Add("pageSize", fmt.Sprintf("%v", req.GetPageSize()))
		}
		if req.GetPageToken() != "" {
			params.Add("pageToken", fmt.Sprintf("%v", req.GetPageToken()))
		}

		baseUrl.RawQuery = params.Encode()

		// Build HTTP headers from client and context metadata.
		hds := append(c.xGoogHeaders, "Content-Type", "application/json")
		headers := gax.BuildHeaders(ctx, hds...)
		e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			if settings.Path != "" {
				baseUrl.Path = settings.Path
			}
			httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
			if err != nil {
				return err
			}
			httpReq.Header = headers

			buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "ListConversations")
			if err != nil {
				return err
			}
			if err := unm.Unmarshal(buf, resp); err != nil {
				return err
			}

			return nil
		}, opts...)
		if e != nil {
			return nil, "", e
		}
		it.Response = resp
		return resp.GetConversations(), resp.GetNextPageToken(), nil
	}

	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetPageSize())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

// AnswerQuery answer query method.
func (c *conversationalSearchRESTClient) AnswerQuery(ctx context.Context, req *discoveryenginepb.AnswerQueryRequest, opts ...gax.CallOption) (*discoveryenginepb.AnswerQueryResponse, error) {
	m := protojson.MarshalOptions{AllowPartial: true, UseEnumNumbers: true}
	jsonReq, err := m.Marshal(req)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v:answer", req.GetServingConfig())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "serving_config", url.QueryEscape(req.GetServingConfig()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	opts = append((*c.CallOptions).AnswerQuery[0:len((*c.CallOptions).AnswerQuery):len((*c.CallOptions).AnswerQuery)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &discoveryenginepb.AnswerQueryResponse{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, jsonReq, "AnswerQuery")
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// GetAnswer gets a Answer.
func (c *conversationalSearchRESTClient) GetAnswer(ctx context.Context, req *discoveryenginepb.GetAnswerRequest, opts ...gax.CallOption) (*discoveryenginepb.Answer, error) {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	opts = append((*c.CallOptions).GetAnswer[0:len((*c.CallOptions).GetAnswer):len((*c.CallOptions).GetAnswer)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &discoveryenginepb.Answer{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "GetAnswer")
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// CreateSession creates a Session.
//
// If the Session to create
// already exists, an ALREADY_EXISTS error is returned.
func (c *conversationalSearchRESTClient) CreateSession(ctx context.Context, req *discoveryenginepb.CreateSessionRequest, opts ...gax.CallOption) (*discoveryenginepb.Session, error) {
	m := protojson.MarshalOptions{AllowPartial: true, UseEnumNumbers: true}
	body := req.GetSession()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v/sessions", req.GetParent())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "parent", url.QueryEscape(req.GetParent()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	opts = append((*c.CallOptions).CreateSession[0:len((*c.CallOptions).CreateSession):len((*c.CallOptions).CreateSession)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &discoveryenginepb.Session{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, jsonReq, "CreateSession")
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// DeleteSession deletes a Session.
//
// If the Session to delete
// does not exist, a NOT_FOUND error is returned.
func (c *conversationalSearchRESTClient) DeleteSession(ctx context.Context, req *discoveryenginepb.DeleteSessionRequest, opts ...gax.CallOption) error {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	return gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("DELETE", baseUrl.String(), nil)
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		_, err = executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "DeleteSession")
		return err
	}, opts...)
}

// UpdateSession updates a Session.
//
// Session action type cannot
// be changed. If the Session
// to update does not exist, a NOT_FOUND error is returned.
func (c *conversationalSearchRESTClient) UpdateSession(ctx context.Context, req *discoveryenginepb.UpdateSessionRequest, opts ...gax.CallOption) (*discoveryenginepb.Session, error) {
	m := protojson.MarshalOptions{AllowPartial: true, UseEnumNumbers: true}
	body := req.GetSession()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v", req.GetSession().GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")
	if req.GetUpdateMask() != nil {
		field, err := protojson.Marshal(req.GetUpdateMask())
		if err != nil {
			return nil, err
		}
		params.Add("updateMask", string(field[1:len(field)-1]))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "session.name", url.QueryEscape(req.GetSession().GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	opts = append((*c.CallOptions).UpdateSession[0:len((*c.CallOptions).UpdateSession):len((*c.CallOptions).UpdateSession)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &discoveryenginepb.Session{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("PATCH", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, jsonReq, "UpdateSession")
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// GetSession gets a Session.
func (c *conversationalSearchRESTClient) GetSession(ctx context.Context, req *discoveryenginepb.GetSessionRequest, opts ...gax.CallOption) (*discoveryenginepb.Session, error) {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	opts = append((*c.CallOptions).GetSession[0:len((*c.CallOptions).GetSession):len((*c.CallOptions).GetSession)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &discoveryenginepb.Session{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "GetSession")
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// ListSessions lists all Sessions by their parent
// DataStore.
func (c *conversationalSearchRESTClient) ListSessions(ctx context.Context, req *discoveryenginepb.ListSessionsRequest, opts ...gax.CallOption) *SessionIterator {
	it := &SessionIterator{}
	req = proto.Clone(req).(*discoveryenginepb.ListSessionsRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*discoveryenginepb.Session, string, error) {
		resp := &discoveryenginepb.ListSessionsResponse{}
		if pageToken != "" {
			req.PageToken = pageToken
		}
		if pageSize > math.MaxInt32 {
			req.PageSize = math.MaxInt32
		} else if pageSize != 0 {
			req.PageSize = int32(pageSize)
		}
		baseUrl, err := url.Parse(c.endpoint)
		if err != nil {
			return nil, "", err
		}
		baseUrl.Path += fmt.Sprintf("/v1alpha/%v/sessions", req.GetParent())

		params := url.Values{}
		params.Add("$alt", "json;enum-encoding=int")
		if req.GetFilter() != "" {
			params.Add("filter", fmt.Sprintf("%v", req.GetFilter()))
		}
		if req.GetOrderBy() != "" {
			params.Add("orderBy", fmt.Sprintf("%v", req.GetOrderBy()))
		}
		if req.GetPageSize() != 0 {
			params.Add("pageSize", fmt.Sprintf("%v", req.GetPageSize()))
		}
		if req.GetPageToken() != "" {
			params.Add("pageToken", fmt.Sprintf("%v", req.GetPageToken()))
		}

		baseUrl.RawQuery = params.Encode()

		// Build HTTP headers from client and context metadata.
		hds := append(c.xGoogHeaders, "Content-Type", "application/json")
		headers := gax.BuildHeaders(ctx, hds...)
		e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			if settings.Path != "" {
				baseUrl.Path = settings.Path
			}
			httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
			if err != nil {
				return err
			}
			httpReq.Header = headers

			buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "ListSessions")
			if err != nil {
				return err
			}
			if err := unm.Unmarshal(buf, resp); err != nil {
				return err
			}

			return nil
		}, opts...)
		if e != nil {
			return nil, "", e
		}
		it.Response = resp
		return resp.GetSessions(), resp.GetNextPageToken(), nil
	}

	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetPageSize())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

// CancelOperation is a utility method from google.longrunning.Operations.
func (c *conversationalSearchRESTClient) CancelOperation(ctx context.Context, req *longrunningpb.CancelOperationRequest, opts ...gax.CallOption) error {
	m := protojson.MarshalOptions{AllowPartial: true, UseEnumNumbers: true}
	jsonReq, err := m.Marshal(req)
	if err != nil {
		return err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v:cancel", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	return gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		_, err = executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, jsonReq, "CancelOperation")
		return err
	}, opts...)
}

// GetOperation is a utility method from google.longrunning.Operations.
func (c *conversationalSearchRESTClient) GetOperation(ctx context.Context, req *longrunningpb.GetOperationRequest, opts ...gax.CallOption) (*longrunningpb.Operation, error) {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1alpha/%v", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	opts = append((*c.CallOptions).GetOperation[0:len((*c.CallOptions).GetOperation):len((*c.CallOptions).GetOperation)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &longrunningpb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "GetOperation")
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// ListOperations is a utility method from google.longrunning.Operations.
func (c *conversationalSearchRESTClient) ListOperations(ctx context.Context, req *longrunningpb.ListOperationsRequest, opts ...gax.CallOption) *OperationIterator {
	it := &OperationIterator{}
	req = proto.Clone(req).(*longrunningpb.ListOperationsRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*longrunningpb.Operation, string, error) {
		resp := &longrunningpb.ListOperationsResponse{}
		if pageToken != "" {
			req.PageToken = pageToken
		}
		if pageSize > math.MaxInt32 {
			req.PageSize = math.MaxInt32
		} else if pageSize != 0 {
			req.PageSize = int32(pageSize)
		}
		baseUrl, err := url.Parse(c.endpoint)
		if err != nil {
			return nil, "", err
		}
		baseUrl.Path += fmt.Sprintf("/v1alpha/%v/operations", req.GetName())

		params := url.Values{}
		params.Add("$alt", "json;enum-encoding=int")
		if req.GetFilter() != "" {
			params.Add("filter", fmt.Sprintf("%v", req.GetFilter()))
		}
		if req.GetPageSize() != 0 {
			params.Add("pageSize", fmt.Sprintf("%v", req.GetPageSize()))
		}
		if req.GetPageToken() != "" {
			params.Add("pageToken", fmt.Sprintf("%v", req.GetPageToken()))
		}

		baseUrl.RawQuery = params.Encode()

		// Build HTTP headers from client and context metadata.
		hds := append(c.xGoogHeaders, "Content-Type", "application/json")
		headers := gax.BuildHeaders(ctx, hds...)
		e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			if settings.Path != "" {
				baseUrl.Path = settings.Path
			}
			httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
			if err != nil {
				return err
			}
			httpReq.Header = headers

			buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "ListOperations")
			if err != nil {
				return err
			}
			if err := unm.Unmarshal(buf, resp); err != nil {
				return err
			}

			return nil
		}, opts...)
		if e != nil {
			return nil, "", e
		}
		it.Response = resp
		return resp.GetOperations(), resp.GetNextPageToken(), nil
	}

	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetPageSize())
	it.pageInfo.Token = req.GetPageToken()

	return it
}
