// Code generated by smithy-go-codegen DO NOT EDIT.

package qbusiness

import (
	"context"
	"fmt"
	awsmiddleware "github.com/aws/aws-sdk-go-v2/aws/middleware"
	"github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream/eventstreamapi"
	"github.com/aws/aws-sdk-go-v2/service/qbusiness/types"
	"github.com/aws/smithy-go/middleware"
	smithysync "github.com/aws/smithy-go/sync"
	smithyhttp "github.com/aws/smithy-go/transport/http"
	"sync"
	"time"
)

// Starts or continues a streaming Amazon Q Business conversation.
func (c *Client) Chat(ctx context.Context, params *ChatInput, optFns ...func(*Options)) (*ChatOutput, error) {
	if params == nil {
		params = &ChatInput{}
	}

	result, metadata, err := c.invokeOperation(ctx, "Chat", params, optFns, c.addOperationChatMiddlewares)
	if err != nil {
		return nil, err
	}

	out := result.(*ChatOutput)
	out.ResultMetadata = metadata
	return out, nil
}

type ChatInput struct {

	// The identifier of the Amazon Q Business application linked to a streaming
	// Amazon Q Business conversation.
	//
	// This member is required.
	ApplicationId *string

	// A token that you provide to identify the chat input.
	ClientToken *string

	// The identifier of the Amazon Q Business conversation.
	ConversationId *string

	// The identifier used to associate a user message with a AI generated response.
	ParentMessageId *string

	// The groups that a user associated with the chat input belongs to.
	UserGroups []string

	// The identifier of the user attached to the chat input.
	UserId *string

	noSmithyDocumentSerde
}

type ChatOutput struct {
	eventStream *ChatEventStream

	// Metadata pertaining to the operation's result.
	ResultMetadata middleware.Metadata

	noSmithyDocumentSerde
}

// GetStream returns the type to interact with the event stream.
func (o *ChatOutput) GetStream() *ChatEventStream {
	return o.eventStream
}

func (c *Client) addOperationChatMiddlewares(stack *middleware.Stack, options Options) (err error) {
	if err := stack.Serialize.Add(&setOperationInputMiddleware{}, middleware.After); err != nil {
		return err
	}
	err = stack.Serialize.Add(&awsRestjson1_serializeOpChat{}, middleware.After)
	if err != nil {
		return err
	}
	err = stack.Deserialize.Add(&awsRestjson1_deserializeOpChat{}, middleware.After)
	if err != nil {
		return err
	}
	if err := addProtocolFinalizerMiddlewares(stack, options, "Chat"); err != nil {
		return fmt.Errorf("add protocol finalizers: %v", err)
	}

	if err = addlegacyEndpointContextSetter(stack, options); err != nil {
		return err
	}
	if err = addEventStreamChatMiddleware(stack, options); err != nil {
		return err
	}
	if err = smithyhttp.AddRequireMinimumProtocol(stack, 2, 0); err != nil {
		return err
	}
	if err = addSetLoggerMiddleware(stack, options); err != nil {
		return err
	}
	if err = addClientRequestID(stack); err != nil {
		return err
	}
	if err = addResolveEndpointMiddleware(stack, options); err != nil {
		return err
	}
	if err = addStreamingEventsPayload(stack); err != nil {
		return err
	}
	if err = addContentSHA256Header(stack); err != nil {
		return err
	}
	if err = addRetry(stack, options); err != nil {
		return err
	}
	if err = addRawResponseToMetadata(stack); err != nil {
		return err
	}
	if err = addRecordResponseTiming(stack); err != nil {
		return err
	}
	if err = addClientUserAgent(stack, options); err != nil {
		return err
	}
	if err = eventstreamapi.AddInitializeStreamWriter(stack); err != nil {
		return err
	}
	if err = addSetLegacyContextSigningOptionsMiddleware(stack); err != nil {
		return err
	}
	if err = addTimeOffsetBuild(stack, c); err != nil {
		return err
	}
	if err = addUserAgentRetryMode(stack, options); err != nil {
		return err
	}
	if err = addIdempotencyToken_opChatMiddleware(stack, options); err != nil {
		return err
	}
	if err = addOpChatValidationMiddleware(stack); err != nil {
		return err
	}
	if err = stack.Initialize.Add(newServiceMetadataMiddleware_opChat(options.Region), middleware.Before); err != nil {
		return err
	}
	if err = addRecursionDetection(stack); err != nil {
		return err
	}
	if err = addRequestIDRetrieverMiddleware(stack); err != nil {
		return err
	}
	if err = addResponseErrorMiddleware(stack); err != nil {
		return err
	}
	if err = addRequestResponseLogging(stack, options); err != nil {
		return err
	}
	if err = addDisableHTTPSMiddleware(stack, options); err != nil {
		return err
	}
	return nil
}

type idempotencyToken_initializeOpChat struct {
	tokenProvider IdempotencyTokenProvider
}

func (*idempotencyToken_initializeOpChat) ID() string {
	return "OperationIdempotencyTokenAutoFill"
}

func (m *idempotencyToken_initializeOpChat) HandleInitialize(ctx context.Context, in middleware.InitializeInput, next middleware.InitializeHandler) (
	out middleware.InitializeOutput, metadata middleware.Metadata, err error,
) {
	if m.tokenProvider == nil {
		return next.HandleInitialize(ctx, in)
	}

	input, ok := in.Parameters.(*ChatInput)
	if !ok {
		return out, metadata, fmt.Errorf("expected middleware input to be of type *ChatInput ")
	}

	if input.ClientToken == nil {
		t, err := m.tokenProvider.GetIdempotencyToken()
		if err != nil {
			return out, metadata, err
		}
		input.ClientToken = &t
	}
	return next.HandleInitialize(ctx, in)
}
func addIdempotencyToken_opChatMiddleware(stack *middleware.Stack, cfg Options) error {
	return stack.Initialize.Add(&idempotencyToken_initializeOpChat{tokenProvider: cfg.IdempotencyTokenProvider}, middleware.Before)
}

func newServiceMetadataMiddleware_opChat(region string) *awsmiddleware.RegisterServiceMetadata {
	return &awsmiddleware.RegisterServiceMetadata{
		Region:        region,
		ServiceID:     ServiceID,
		OperationName: "Chat",
	}
}

// ChatEventStream provides the event stream handling for the Chat operation.
//
// For testing and mocking the event stream this type should be initialized via
// the NewChatEventStream constructor function. Using the functional options
// to pass in nested mock behavior.
type ChatEventStream struct {
	// ChatInputStreamWriter is the EventStream writer for the ChatInputStream events.
	// This value is automatically set by the SDK when the API call is made Use this
	// member when unit testing your code with the SDK to mock out the EventStream
	// Writer.
	//
	// Must not be nil.
	Writer ChatInputStreamWriter

	// ChatOutputStreamReader is the EventStream reader for the ChatOutputStream
	// events. This value is automatically set by the SDK when the API call is made Use
	// this member when unit testing your code with the SDK to mock out the EventStream
	// Reader.
	//
	// Must not be nil.
	Reader ChatOutputStreamReader

	done      chan struct{}
	closeOnce sync.Once
	err       *smithysync.OnceErr
}

// NewChatEventStream initializes an ChatEventStream.
// This function should only be used for testing and mocking the ChatEventStream
// stream within your application.
//
// The Writer member must be set before writing events to the stream.
//
// The Reader member must be set before reading events from the stream.
func NewChatEventStream(optFns ...func(*ChatEventStream)) *ChatEventStream {
	es := &ChatEventStream{
		done: make(chan struct{}),
		err:  smithysync.NewOnceErr(),
	}
	for _, fn := range optFns {
		fn(es)
	}
	return es
}

// Send writes the event to the stream blocking until the event is written.
// Returns an error if the event was not written.
func (es *ChatEventStream) Send(ctx context.Context, event types.ChatInputStream) error {
	return es.Writer.Send(ctx, event)
}

// Events returns a channel to read events from.
func (es *ChatEventStream) Events() <-chan types.ChatOutputStream {
	return es.Reader.Events()
}

// Close closes the stream. This will also cause the stream to be closed.
// Close must be called when done using the stream API. Not calling Close
// may result in resource leaks.
//
// Will close the underlying EventStream writer and reader, and no more events can be
// sent or received.
func (es *ChatEventStream) Close() error {
	es.closeOnce.Do(es.safeClose)
	return es.Err()
}

func (es *ChatEventStream) safeClose() {
	close(es.done)

	t := time.NewTicker(time.Second)
	defer t.Stop()
	writeCloseDone := make(chan error)
	go func() {
		if err := es.Writer.Close(); err != nil {
			es.err.SetError(err)
		}
		close(writeCloseDone)
	}()
	select {
	case <-t.C:
	case <-writeCloseDone:
	}

	es.Reader.Close()
}

// Err returns any error that occurred while reading or writing EventStream Events
// from the service API's response. Returns nil if there were no errors.
func (es *ChatEventStream) Err() error {
	if err := es.err.Err(); err != nil {
		return err
	}

	if err := es.Writer.Err(); err != nil {
		return err
	}

	if err := es.Reader.Err(); err != nil {
		return err
	}

	return nil
}

func (es *ChatEventStream) waitStreamClose() {
	type errorSet interface {
		ErrorSet() <-chan struct{}
	}

	var inputErrCh <-chan struct{}
	if v, ok := es.Writer.(errorSet); ok {
		inputErrCh = v.ErrorSet()
	}

	var outputErrCh <-chan struct{}
	if v, ok := es.Reader.(errorSet); ok {
		outputErrCh = v.ErrorSet()
	}
	var outputClosedCh <-chan struct{}
	if v, ok := es.Reader.(interface{ Closed() <-chan struct{} }); ok {
		outputClosedCh = v.Closed()
	}

	select {
	case <-es.done:
	case <-inputErrCh:
		es.err.SetError(es.Writer.Err())
		es.Close()

	case <-outputErrCh:
		es.err.SetError(es.Reader.Err())
		es.Close()

	case <-outputClosedCh:
		if err := es.Reader.Err(); err != nil {
			es.err.SetError(es.Reader.Err())
		}
		es.Close()

	}
}