package redriver

import (
	"context"
	"encoding/json"
	"fmt"
	"io"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/sqs"
	"github.com/aws/aws-sdk-go-v2/service/sqs/types"
	"github.com/fgm/izidic"

	"code.osinet.fr/fgm/sqs_demo/services"
)

type ItemsKeys struct {
	MessageID     string
	ReceiptHandle string
}

// Redriver is a redrive-oriented facade in front of the sqs.Client API.
type Redriver interface {
	ListQueues(ctx context.Context, prefix string) (QueueUrls []string, err error)
	GetDLQ(ctx context.Context, qName string) (QueueUrls string, err error)
	GetQueueInfo(ctx context.Context, qName string) (*QueueInfo, error)
	GetQueueItems(ctx context.Context, qName string, max int) ([]sqs.ReceiveMessageOutput, error)
	DeleteItems(ctx context.Context, qName string, itemsIDs []ItemsKeys) error
	Purge(ctx context.Context, qName string) error
	RedriveItems(ctx context.Context, qName string, itemIDs []ItemsKeys) error
}

type redriver struct {
	io.Writer
	*sqs.Client
}

func (r redriver) ListQueues(ctx context.Context, prefix string) (QueueUrls []string, err error) {
	lqi := &sqs.ListQueuesInput{
		MaxResults:      aws.Int32(1000),
		NextToken:       nil,
		QueueNamePrefix: aws.String(prefix),
	}
	lqo, err := r.Client.ListQueues(ctx, lqi)
	if err != nil {
		return nil, fmt.Errorf("listing queues: %w", err)
	}
	return lqo.QueueUrls, nil
}

func (r redriver) GetDLQ(ctx context.Context, qName string) (QueueUrl string, err error) {
	qui := &sqs.GetQueueUrlInput{QueueName: &qName}
	qu, err := r.GetQueueUrl(ctx, qui)
	if err != nil {
		return "", fmt.Errorf("failed getting URL for queue %q: %w", qName, err)
	}
	qai := &sqs.GetQueueAttributesInput{
		QueueUrl:       qu.QueueUrl,
		AttributeNames: []types.QueueAttributeName{types.QueueAttributeNameRedrivePolicy},
	}
	qao, err := r.Client.GetQueueAttributes(ctx, qai)
	if err != nil {
		return "", fmt.Errorf("failed getting DLQ for queue %q: %w", qName, err)
	}
	rp, ok := qao.Attributes[string(types.QueueAttributeNameRedrivePolicy)]
	if !ok {
		return "", nil
	}
	var qrp QueueInfoAttributesRedrivePolicy
	if err = json.Unmarshal([]byte(rp), &qrp); err != nil {
		return "", fmt.Errorf("failed parsing redrive policy for queue %q %w",
			qName, err)
	}
	qURL, err := URLFromARNString(qrp.DeadLetterTargetARN)
	if err != nil {
		return "", fmt.Errorf(
			"failed converting queue %q ARN to URL: %w", qName, err)
	}
	return qURL, nil
}

func (r redriver) GetQueueInfo(ctx context.Context, qName string) (*QueueInfo, error) {
	// TODO implement me
	panic("implement me")
}

func (r redriver) GetQueueItems(ctx context.Context, qName string, max int) ([]sqs.ReceiveMessageOutput, error) {
	// TODO implement me
	panic("implement me")
}

func (r redriver) DeleteItems(ctx context.Context, qName string, itemsIDs []ItemsKeys) error {
	// TODO implement me
	panic("implement me")
}

func (r redriver) Purge(ctx context.Context, qName string) error {
	// TODO implement me
	panic("implement me")
}

func (r redriver) RedriveItems(ctx context.Context, qName string, itemIDs []ItemsKeys) error {
	// TODO implement me
	panic("implement me")
}

func RedriverService(dic *izidic.Container) (any, error) {
	cli := dic.MustService(services.SvcClient).(*sqs.Client)
	w := dic.MustParam(services.PWriter).(io.Writer)
	return &redriver{
		Writer: w,
		Client: cli,
	}, nil
}