You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: api_op_ListEnvironments.go
    path of file: ./repos/aws-sdk-go-v2/service/appconfig
    
    the code of the file until where you have to start completion: // Code generated by smithy-go-codegen DO NOT EDIT.

package appconfig

import (
	"context"
	"fmt"
	awsmiddleware "github.com/aws/aws-sdk-go-v2/aws/middleware"
	"github.com/aws/aws-sdk-go-v2/service/appconfig/types"
	"github.com/aws/smithy-go/middleware"
	smithyhttp "github.com/aws/smithy-go/transport/http"
)

// Lists the environments for an application.
func (c *Client) ListEnvironments(ctx context.Context, params *ListEnvironmentsInput, optFns ...func(*Options)) (*ListEnvironmentsOutput, error) {
	if params == nil {
		params = &ListEnvironmentsInput{}
	}

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

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

type ListEnvironmentsInput struct {

	// The application ID.
	//
	// This member is required.
	ApplicationId *string

	// The maximum number of items to return for this call. The call also returns a
	// token that you can specify in a subsequent call to get the next set of results.
	MaxResults *int32

	// A to
    
func (c *Client) addOperationListEnvironmentsMiddlewares(stack *middleware.Stack, options Options) (err error) {
	if err := stack.Serialize.Add(&setOperationInputMiddleware{}, middleware.After); err != nil {
		return err
	}
	err = stack.Serialize.Add(&awsRestjson1_serializeOpListEnvironments{}, middleware.After)
	if err != nil {
		return err
	}
	err = stack.Deserialize.Add(&awsRestjson1_deserializeOpListEnvironments{}, middleware.After)
	if err != nil {
		return err
	}
	if err := addProtocolFinalizerMiddlewares(stack, options, "ListEnvironments"); err != nil {
		return fmt.Errorf("add protocol finalizers: %v", err)
	}

	if err = addlegacyEndpointContextSetter(stack, options); err != nil {
		return err
	}
	if err = addSetLoggerMiddleware(stack, options); err != nil {
		return err
	}
	if err = addClientRequestID(stack); err != nil {
		return err
	}
	if err = addComputeContentLength(stack); err != nil {
		return err
	}
	if err = addResolveEndpointMiddleware(stack, options); err != nil {
		return err
	}
	if err = addComputePayloadSHA256(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 = smithyhttp.AddErrorCloseResponseBodyMiddleware(stack); err != nil {
		return err
	}
	if err = smithyhttp.AddCloseResponseBodyMiddleware(stack); err != nil {
		return err
	}
	if err = addSetLegacyContextSigningOptionsMiddleware(stack); err != nil {
		return err
	}
	if err = addOpListEnvironmentsValidationMiddleware(stack); err != nil {
		return err
	}
	if err = stack.Initialize.Add(newServiceMetadataMiddleware_opListEnvironments(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
}