package service

import (
	"context"
	"fmt"
	"github.com/gofiber/fiber/v2"
	"github.com/google/uuid"
	"github.com/minio/minio-go/v7"
	"github.com/rs/zerolog"
	"io"
	"log"
	"math/rand"
	"mime"
	"mime/multipart"
	"netidhub-saas-be/app/module/article_files/mapper"
	"netidhub-saas-be/app/module/article_files/repository"
	"netidhub-saas-be/app/module/article_files/request"
	"netidhub-saas-be/app/module/article_files/response"
	usersRepository "netidhub-saas-be/app/module/users/repository"
	config "netidhub-saas-be/config/config"
	minioStorage "netidhub-saas-be/config/config"
	"netidhub-saas-be/utils/paginator"
	utilSvc "netidhub-saas-be/utils/service"
	"os"
	"path/filepath"
	"strconv"
	"strings"
	"sync"
	"time"
)

// ArticleFilesService
type articleFilesService struct {
	Repo         repository.ArticleFilesRepository
	UsersRepo    usersRepository.UsersRepository
	Log          zerolog.Logger
	Cfg          *config.Config
	MinioStorage *minioStorage.MinioStorage
}

// ArticleFilesService define interface of IArticleFilesService
type ArticleFilesService interface {
	All(authToken string, req request.ArticleFilesQueryRequest) (articleFiles []*response.ArticleFilesResponse, paging paginator.Pagination, err error)
	Show(authToken string, id uint) (articleFiles *response.ArticleFilesResponse, err error)
	Save(authToken string, c *fiber.Ctx, id uint) error
	SaveAsync(authToken string, c *fiber.Ctx, id uint) error
	Update(authToken string, id uint, req request.ArticleFilesUpdateRequest) (err error)
	GetUploadStatus(c *fiber.Ctx) (progress int, err error)
	Delete(authToken string, id uint) error
	Viewer(authToken string, c *fiber.Ctx) error
}

// NewArticleFilesService init ArticleFilesService
func NewArticleFilesService(repo repository.ArticleFilesRepository, log zerolog.Logger, cfg *config.Config, minioStorage *minioStorage.MinioStorage, usersRepo usersRepository.UsersRepository) ArticleFilesService {

	return &articleFilesService{
		Repo:         repo,
		UsersRepo:    usersRepo,
		Log:          log,
		Cfg:          cfg,
		MinioStorage: minioStorage,
	}
}

var (
	progressMap  = make(map[string]int) // Menyimpan progress upload per UploadID
	progressLock = sync.Mutex{}
)

type progressWriter struct {
	uploadID     string
	totalSize    int64
	uploadedSize *int64
}

// All implement interface of ArticleFilesService
func (_i *articleFilesService) All(authToken string, req request.ArticleFilesQueryRequest) (articleFiless []*response.ArticleFilesResponse, paging paginator.Pagination, err error) {
	// Extract clientId from authToken
	var clientId *uuid.UUID
	if authToken != "" {
		user := utilSvc.GetUserInfo(_i.Log, _i.UsersRepo, authToken)
		if user != nil && user.ClientId != nil {
			clientId = user.ClientId
			_i.Log.Info().Interface("clientId", clientId).Msg("Extracted clientId from auth token")
		}
	}

	results, paging, err := _i.Repo.GetAll(clientId, req)
	if err != nil {
		return
	}

	host := _i.Cfg.App.Domain

	for _, result := range results {
		articleFiless = append(articleFiless, mapper.ArticleFilesResponseMapper(result, host))
	}

	return
}

func (_i *articleFilesService) Show(authToken string, id uint) (articleFiles *response.ArticleFilesResponse, err error) {
	// Extract clientId from authToken
	var clientId *uuid.UUID
	if authToken != "" {
		user := utilSvc.GetUserInfo(_i.Log, _i.UsersRepo, authToken)
		if user != nil && user.ClientId != nil {
			clientId = user.ClientId
			_i.Log.Info().Interface("clientId", clientId).Msg("Extracted clientId from auth token")
		}
	}

	result, err := _i.Repo.FindOne(clientId, id)
	if err != nil {
		return nil, err
	}

	host := _i.Cfg.App.Domain

	return mapper.ArticleFilesResponseMapper(result, host), nil
}

func (_i *articleFilesService) SaveAsync(authToken string, c *fiber.Ctx, id uint) (err error) {
	// Extract clientId from authToken
	var clientId *uuid.UUID
	if authToken != "" {
		user := utilSvc.GetUserInfo(_i.Log, _i.UsersRepo, authToken)
		if user != nil && user.ClientId != nil {
			clientId = user.ClientId
			_i.Log.Info().Interface("clientId", clientId).Msg("Extracted clientId from auth token")
		}
	}

	bucketName := _i.MinioStorage.Cfg.ObjectStorage.MinioStorage.BucketName

	ctx := context.Background()

	form, err := c.MultipartForm()

	if err != nil {
		return err
	}
	//filess := form.File["files"]

	// Create minio connection.
	minioClient, err := _i.MinioStorage.ConnectMinio()
	if err != nil {
		// Return status 500 and minio connection error.
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"error": true,
			"msg":   err.Error(),
		})
	}

	for _, files := range form.File {

		_i.Log.Info().Str("timestamp", time.Now().
			Format(time.RFC3339)).Str("Service:Resource", "Uploader:: top").
			Interface("files", files).Msg("")

		for _, fileHeader := range files {
			_i.Log.Info().Str("timestamp", time.Now().
				Format(time.RFC3339)).Str("Service:Resource", "Uploader:: loop").
				Interface("data", fileHeader).Msg("")

			filename := filepath.Base(fileHeader.Filename)
			filenameAlt := filepath.Clean(filename[:len(filename)-len(filepath.Ext(filename))])
			filename = strings.ReplaceAll(filename, " ", "")
			filenameWithoutExt := filepath.Clean(filename[:len(filename)-len(filepath.Ext(filename))])
			extension := filepath.Ext(fileHeader.Filename)[1:]

			now := time.Now()
			rand.New(rand.NewSource(now.UnixNano()))
			randUniqueId := rand.Intn(1000000)
			uploadID := strconv.Itoa(randUniqueId)

			newFilenameWithoutExt := filenameWithoutExt + "_" + strconv.Itoa(randUniqueId)
			newFilename := newFilenameWithoutExt + "." + extension

			objectName := fmt.Sprintf("articles/upload/%d/%d/%s", now.Year(), now.Month(), newFilename)
			fileSize := strconv.FormatInt(fileHeader.Size, 10)
			fileSizeInt := fileHeader.Size

			_i.Log.Info().Str("timestamp", time.Now().
				Format(time.RFC3339)).Str("Service:Resource", "Uploader:: top").
				Interface("Start upload", uploadID).Msg("")

			req := request.ArticleFilesCreateRequest{
				ArticleId: id,
				UploadId:  &uploadID,
				FilePath:  &objectName,
				FileName:  &newFilename,
				FileAlt:   &filenameAlt,
				Size:      &fileSize,
			}

			err = _i.Repo.Create(clientId, req.ToEntity())
			if err != nil {
				return err
			}

			src, err := fileHeader.Open()
			if err != nil {
				return err
			}
			defer src.Close()

			tempFilePath := fmt.Sprintf("/tmp/%s", newFilename)
			tempFile, err := os.Create(tempFilePath)
			if err != nil {
				return err
			}
			defer tempFile.Close()

			// Copy file ke direktori sementara
			_, err = io.Copy(tempFile, src)
			if err != nil {
				return err
			}

			go uploadToMinIO(ctx, _i.Log, minioClient, uploadID, tempFilePath, bucketName, objectName, fileSizeInt)
		}
	}

	_i.Log.Info().Str("timestamp", time.Now().
		Format(time.RFC3339)).Str("Service:Resource", "User:All").
		Interface("data", "Successfully uploaded").Msg("")

	return
}

func (_i *articleFilesService) Save(authToken string, c *fiber.Ctx, id uint) (err error) {
	// Extract clientId from authToken
	var clientId *uuid.UUID
	if authToken != "" {
		user := utilSvc.GetUserInfo(_i.Log, _i.UsersRepo, authToken)
		if user != nil && user.ClientId != nil {
			clientId = user.ClientId
			_i.Log.Info().Interface("clientId", clientId).Msg("Extracted clientId from auth token")
		}
	}

	bucketName := _i.MinioStorage.Cfg.ObjectStorage.MinioStorage.BucketName

	form, err := c.MultipartForm()

	if err != nil {
		return err
	}
	//filess := form.File["files"]

	// Create minio connection.
	minioClient, err := _i.MinioStorage.ConnectMinio()

	if err != nil {
		// Return status 500 and minio connection error.
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"error": true,
			"msg":   err.Error(),
		})
	}

	for _, files := range form.File {

		_i.Log.Info().Str("timestamp", time.Now().
			Format(time.RFC3339)).Str("Service:Resource", "Uploader:: top").
			Interface("files", files).Msg("")

		for _, fileHeader := range files {
			_i.Log.Info().Str("timestamp", time.Now().
				Format(time.RFC3339)).Str("Service:Resource", "Uploader:: loop").
				Interface("data", fileHeader).Msg("")

			src, err := fileHeader.Open()
			if err != nil {
				return err
			}
			defer src.Close()

			filename := filepath.Base(fileHeader.Filename)
			filenameAlt := filepath.Clean(filename[:len(filename)-len(filepath.Ext(filename))])
			filename = strings.ReplaceAll(filename, " ", "")
			filenameWithoutExt := filepath.Clean(filename[:len(filename)-len(filepath.Ext(filename))])
			extension := filepath.Ext(fileHeader.Filename)[1:]

			now := time.Now()
			rand.New(rand.NewSource(now.UnixNano()))
			randUniqueId := rand.Intn(1000000)

			newFilenameWithoutExt := filenameWithoutExt + "_" + strconv.Itoa(randUniqueId)
			newFilename := newFilenameWithoutExt + "." + extension

			objectName := fmt.Sprintf("articles/upload/%d/%d/%s", now.Year(), now.Month(), newFilename)
			fileSize := strconv.FormatInt(fileHeader.Size, 10)

			req := request.ArticleFilesCreateRequest{
				ArticleId: id,
				FilePath:  &objectName,
				FileName:  &newFilename,
				FileAlt:   &filenameAlt,
				Size:      &fileSize,
			}

			err = _i.Repo.Create(clientId, req.ToEntity())
			if err != nil {
				return err
			}

			// Upload file ke MinIO
			_, err = minioClient.PutObject(context.Background(), bucketName, objectName, src, fileHeader.Size, minio.PutObjectOptions{})
			if err != nil {
				return err
			}
		}
	}

	_i.Log.Info().Str("timestamp", time.Now().
		Format(time.RFC3339)).Str("Service:Resource", "User:All").
		Interface("data", "Successfully uploaded").Msg("")

	return
}

func (_i *articleFilesService) Update(authToken string, id uint, req request.ArticleFilesUpdateRequest) (err error) {
	// Extract clientId from authToken
	var clientId *uuid.UUID
	if authToken != "" {
		user := utilSvc.GetUserInfo(_i.Log, _i.UsersRepo, authToken)
		if user != nil && user.ClientId != nil {
			clientId = user.ClientId
			_i.Log.Info().Interface("clientId", clientId).Msg("Extracted clientId from auth token")
		}
	}

	_i.Log.Info().Interface("data", req).Msg("")
	return _i.Repo.Update(clientId, id, req.ToEntity())
}

func (_i *articleFilesService) Delete(authToken string, id uint) error {
	// Extract clientId from authToken
	var clientId *uuid.UUID
	if authToken != "" {
		user := utilSvc.GetUserInfo(_i.Log, _i.UsersRepo, authToken)
		if user != nil && user.ClientId != nil {
			clientId = user.ClientId
			_i.Log.Info().Interface("clientId", clientId).Msg("Extracted clientId from auth token")
		}
	}

	result, err := _i.Repo.FindOne(clientId, id)
	if err != nil {
		return err
	}
	result.IsActive = false
	return _i.Repo.Update(clientId, id, result)
}

func (_i *articleFilesService) Viewer(authToken string, c *fiber.Ctx) (err error) {
	// Extract clientId from authToken
	var clientId *uuid.UUID
	if authToken != "" {
		user := utilSvc.GetUserInfo(_i.Log, _i.UsersRepo, authToken)
		if user != nil && user.ClientId != nil {
			clientId = user.ClientId
			_i.Log.Info().Interface("clientId", clientId).Msg("Extracted clientId from auth token")
		}
	}

	filename := c.Params("filename")
	result, err := _i.Repo.FindByFilename(clientId, filename)
	if err != nil {
		return err
	}

	ctx := context.Background()
	bucketName := _i.MinioStorage.Cfg.ObjectStorage.MinioStorage.BucketName
	objectName := *result.FilePath

	_i.Log.Info().Str("timestamp", time.Now().
		Format(time.RFC3339)).Str("Service:Resource", "Article:Uploads").
		Interface("data", objectName).Msg("")

	// Create minio connection.
	minioClient, err := _i.MinioStorage.ConnectMinio()
	if err != nil {
		// Return status 500 and minio connection error.
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"error": true,
			"msg":   err.Error(),
		})
	}

	fileContent, err := minioClient.GetObject(ctx, bucketName, objectName, minio.GetObjectOptions{})
	if err != nil {
		log.Fatalln(err)
	}
	defer fileContent.Close()

	// Tentukan Content-Type berdasarkan ekstensi file
	contentType := mime.TypeByExtension("." + getFileExtension(objectName))
	if contentType == "" {
		contentType = "application/octet-stream" // fallback jika tidak ada tipe MIME yang cocok
	}

	c.Set("Content-Type", contentType)

	if _, err := io.Copy(c.Response().BodyWriter(), fileContent); err != nil {
		return err
	}

	return
}

func getFileExtension(filename string) string {
	// split file name
	parts := strings.Split(filename, ".")

	// jika tidak ada ekstensi, kembalikan string kosong
	if len(parts) == 1 || (len(parts) == 2 && parts[0] == "") {
		return ""
	}

	// ambil ekstensi terakhir
	return parts[len(parts)-1]
}

func uploadTempFile(log zerolog.Logger, fileHeader *multipart.FileHeader, filePath string) {
	src, err := fileHeader.Open()
	if err != nil {
		log.Info().Str("timestamp", time.Now().
			Format(time.RFC3339)).Str("Service:Resource", "Article:uploadToMinIO-0").
			Interface("err", err).Msg("")
	}
	defer src.Close()

	tempFile, err := os.Create(filePath)
	if err != nil {
		log.Info().Str("timestamp", time.Now().
			Format(time.RFC3339)).Str("Service:Resource", "Article:uploadToMinIO-1").
			Interface("err", err).Msg("")
	}
	defer tempFile.Close()

	// Copy file ke direktori sementara
	_, err = io.Copy(tempFile, src)
	if err != nil {
		log.Info().Str("timestamp", time.Now().
			Format(time.RFC3339)).Str("Service:Resource", "Article:uploadToMinIO-2").
			Interface("err", err).Msg("")
	}
}

func uploadToMinIO(ctx context.Context, log zerolog.Logger, minioClient *minio.Client, uploadID, filePath, bucketName string, objectName string, fileSize int64) {
	file, err := os.Open(filePath)
	if err != nil {
		log.Info().Str("timestamp", time.Now().
			Format(time.RFC3339)).Str("Service:Resource", "Article:uploadToMinIO-3").
			Interface("err", err).Msg("")
		return
	}
	defer file.Close()

	// Upload file ke MinIO dengan progress tracking
	uploadProgress := int64(0)
	reader := io.TeeReader(file, &progressWriter{uploadID: uploadID, totalSize: fileSize, uploadedSize: &uploadProgress})

	_, err = minioClient.PutObject(ctx, bucketName, objectName, reader, fileSize, minio.PutObjectOptions{})
	if err != nil {

		log.Info().Str("timestamp", time.Now().
			Format(time.RFC3339)).Str("Service:Resource", "Article:uploadToMinIO-4").
			Interface("err", err).Msg("")
		return
	}

	// Upload selesai, update progress menjadi 100
	progressLock.Lock()
	progressMap[uploadID] = 100
	progressLock.Unlock()

	go removeFileTemp(log, filePath)
}

func removeFileTemp(log zerolog.Logger, filePath string) {
	err := os.Remove(filePath)
	if err != nil {
		log.Info().Str("timestamp", time.Now().
			Format(time.RFC3339)).Str("Service:Resource", "Article:uploadToMinIO-5").
			Interface("Failed to remove temporary file", err).Msg("")
	} else {
		log.Info().Str("timestamp", time.Now().
			Format(time.RFC3339)).Str("Service:Resource", "Article:uploadToMinIO-6").
			Interface("err", "Temporary file removed").Msg("")
	}
}

func (p *progressWriter) Write(data []byte) (int, error) {
	n := len(data)
	progressLock.Lock()
	defer progressLock.Unlock()

	*p.uploadedSize += int64(n)
	progress := int(float64(*p.uploadedSize) / float64(p.totalSize) * 100)

	// Update progress di map
	progressMap[p.uploadID] = progress

	return n, nil
}

func (_i *articleFilesService) GetUploadStatus(c *fiber.Ctx) (progress int, err error) {
	uploadID := c.Params("uploadId")

	// Ambil progress dari map
	progressLock.Lock()
	progress, _ = progressMap[uploadID]
	progressLock.Unlock()

	return progress, nil
}