package storage

import (
	"encoding/base64"
	"encoding/json"
	"fmt"
	"io"
	"io/fs"
	"os"
	"path"
	"strings"

	"gosimplenpm/internal/serviceidos"
	"path/filepath"

	"github.com/sirupsen/logrus"
)

type FSStorage struct{}

func (f *FSStorage) GetIndexJsonFromStore(packageName string, registryPath string, log *logrus.Logger) (string, bool, error) {
	fileToServe := ""
	found := false

	err := filepath.WalkDir(registryPath, func(fp string, info fs.DirEntry, e error) error {
		if strings.Contains(fp, path.Join(packageName, "index.json")) {
			fileToServe = fp
			found = true
		}
		return e
	})

	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "get-index-json-from-store",
		}).Errorf("List files error: +%v\n", err)
		return fileToServe, found, err
	}

	if fileToServe == "" && !found {
		fileToServe = path.Join(registryPath, packageName, "index.json")
	}

	return fileToServe, found, nil
}

func (f *FSStorage) GetTarFromStore(packageName string, tarFileName string, registryPath string, log *logrus.Logger) (string, error) {
	fileToServe := ""

	err := filepath.WalkDir(registryPath, func(fp string, info fs.DirEntry, e error) error {
		if strings.Contains(fp, path.Join(packageName, tarFileName)) {
			fileToServe = fp
		}
		return e
	})

	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "get-tar-from-store",
		}).Errorf("List files error: +%v\n", err)
		return fileToServe, err
	}

	if fileToServe == "" {
		return fileToServe, fmt.Errorf("file %s is not found for package %s", tarFileName, packageName)
	}

	file, err := os.Open(fileToServe)
	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "get-tar-from-store",
		}).Errorf("Open error: %s\n", fileToServe)
		return "", err
	}
	defer file.Close()

	bs, err := io.ReadAll(file)
	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "get-tar-from-store",
		}).Errorf("File Read error: %s\n", fileToServe)
		return "", err
	}

	return base64.StdEncoding.EncodeToString(bs), err
}

func (f *FSStorage) ReadIndexJson(fPath string, res *serviceidos.IndexJson, log *logrus.Logger) error {
	jsonFile, err := os.Open(fPath)
	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "read-index-json",
		}).Errorf("File Not found: %s\n", fPath)
		return err
	}

	defer jsonFile.Close()

	err = json.NewDecoder(jsonFile).Decode(res)
	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "read-index-json",
		}).Errorf("Unmarshalerror: %+v\n", err)
		return err
	}

	return nil
}

func (f *FSStorage) WriteIndexJson(fPath string, res *serviceidos.IndexJson, log *logrus.Logger) error {
	// Need to create the directory first
	parent := path.Dir(fPath)
	err := os.MkdirAll(parent, os.ModePerm)
	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "write-index-json",
		}).Errorf("Folder (%s) creation failed.\n", fPath)
		return err
	}

	// Create the file
	jsonFile, err := os.Create(fPath)

	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "write-index-json",
		}).Errorf("Creation error for path(%s): %+v\n ", fPath, err)
		return err
	}

	defer jsonFile.Close()

	err = json.NewEncoder(jsonFile).Encode(res)
	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "write-index-json",
		}).Debugf("Marshalerror: %+v\n", err)
		return err
	}

	return nil
}

func (f *FSStorage) WritePackageToStore(fPath string, data string, log *logrus.Logger) error {
	dec, err := base64.StdEncoding.DecodeString(data)
	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "write-package-to-store",
		}).Errorf("Base64 Decode error: %+v\n", err)
		return err
	}

	dataFile, err := os.Create(fPath)
	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "write-package-to-store",
		}).Errorf("Creation error: %s\n", fPath)
		return err
	}

	defer dataFile.Close()

	_, err = dataFile.Write(dec)
	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "write-package-to-store",
		}).Errorf("Write error: %s\n", fPath)
		return err
	}

	err = dataFile.Sync()
	if err != nil {
		log.WithFields(logrus.Fields{
			"function": "write-package-to-store",
		}).Errorf("Sync error: %s\n", fPath)
		return err
	}

	return nil
}