package main

import (
	"context"
	"log"
	"net/http"
	"strconv"
	"github.com/aws/aws-sdk-go-v2/config"
	"github.com/gabrielhora/mps3"
)

func main() {
	server := http.NewServeMux()

	server.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
		// no need to call `req.ParseMultipartForm()` or `req.ParseForm()`, the middleware
		// will process the data, upload the files and return the following information.

		// suppose a multipart form was posted with fields "file" and "name".
		fileKey := req.Form.Get("file")                                    // "<field>" contains the S3 key where this file was saved
		fileName := req.Form.Get("file_name")                              // "<field>_name" is the original uploaded file name
		fileType := req.Form.Get("file_type")                              // "<field>_type" contains the file content type
		fileSize, _ := strconv.ParseInt(req.Form.Get("file_size"), 10, 64) // "<field>_size" is the file size

		name := req.Form.Get("name") // other fields are accessed normally

		// ...
	}))
	
	s3cfg, _ := config.LoadDefaultConfig(context.Background())

	s3, err := mps3.New(mps3.Config{
		// S3Config you can specify static credentials or custom endpoints if needed.
		// By default if not specified the middleware you load the default configuration.
		S3Config: &s3cfg,

		// ACL used for the bucket when CreateBucket is true
		BucketACL: "private",

		// If true it will try to create the bucket, if the bucket already exists and
		// it belongs to the same account ("BucketAlreadyOwnedByYou") it won't do anything
		CreateBucket: true,

		// ACL used for uploaded files
		FileACL: "private",

		// A logger that is used to print out error messages during request handling
		Logger: log.Default(),

		// Size of the upload chunk to S3 (minimum is 5MB)
		PartSize: 1024 * 1024 * 5,

		// Function called for uploaded files to determine their S3 key prefix.
		// This is the default implementation.
		PrefixFunc: func(req *http.Request) string {
			return time.Now().UTC().Format("/2006/01/02/")
		},
	})
	if err != nil {
		// handle error
	}

	// To use it, just wrap the Handler (either the whole server or specific routes)
	_ = http.ListenAndServe(":8080", s3.Wrap(server))
}