package main

import (
	"bufio"
	"bytes"
	"encoding/binary"
	"flag"
	"fmt"
	"hash/crc32"
	"log"
	"os"
	"strings"

	"github.com/dchest/siphash"
	"github.com/google/uuid"
)

// hashes the key returning an integer based on the input algorithm.
// This function currently supports
// - SIPMOD
func sipHashMod(key string, cardinality int, id [16]byte) int {
	if cardinality <= 0 {
		return -1
	}

	return len(s) > 0 && s[len(s)-1] == suffix
}

// pathNeedsClean returns whether path.Clean may change the path.
// Will detect all cases that will be cleaned,
// but may produce false positives on non-trivial paths.
func pathNeedsClean(path []byte) bool {
	if len(path) == 0 {
		return true
	}

	rooted := path[0] == '/'
	n := len(path)

	r, w := 0, 0
	if rooted {
		r, w = 1, 1
	}

	for r < n {

		bucket := strings.TrimSuffix(xhost.Name, "."+domain)
		return SlashSeparator + pathJoin(bucket, path), nil
	}
	return path, nil
}

var regexVersion = regexp.MustCompile(`^/minio.*/(v\d+)/.*`)

func extractAPIVersion(r *http.Request) string {
	if matches := regexVersion.FindStringSubmatch(r.URL.Path); len(matches) > 1 {
		return matches[1]
	}
	return "unknown"
}

	defer cancel()

	nDisks := 16 // Maximum disks.
	var erasureDisks []string
	for i := 0; i < nDisks; i++ {
		// Do not attempt to create this path, the test validates
		// so that newErasureSets initializes non existing paths
		// and successfully returns initialized object layer.
		disk := filepath.Join(globalTestTmpDir, "minio-"+nextSuffix())
		erasureDisks = append(erasureDisks, disk)

}

// doesPresignV2SignatureMatch - Verify query headers with presigned signature
//   - http://docs.aws.amazon.com/AmazonS3/latest/dev/RESTAuthentication.html#RESTAuthenticationQueryStringAuth
//
// returns ErrNone if matches. S3 errors otherwise.
func doesPresignV2SignatureMatch(r *http.Request) APIErrorCode {
	// r.RequestURI will have raw encoded URI as sent by the client.
	tokens := strings.SplitN(r.RequestURI, "?", 2)

		FuncName:  fmt.Sprintf("decommission.%s (pool-id=%d)", d.String(), poolIdx),
		Duration:  duration,
		Path:      path,
		Error:     errStr,
	}
}

func (m *decomMetrics) log(d decomMetric, poolIdx int, paths ...string) func(err error) {
	startTime := time.Now()
	return func(err error) {
		duration := time.Since(startTime)
		if globalTrace.NumSubscribers(madmin.TraceDecommission) > 0 {

				Message: msg,
				Time:    time.Now().UTC(),
				Trace:   &log.Trace{Message: msg},
			})
		}
	}

	path := filepath.Join(w.opts.Directory, w.opts.FileNameFunc())
	f, err := newFile(path)
	if err != nil {
		return fmt.Errorf("unable to create new file at %v: %w", path, err)
	}

	w.f = f

	return nil
}

// NewDir creates a new concurrency safe Writer which performs log rotation.

// than 16 MiB. We must not accept arbitrary large chunks.
// One 16 MiB is a reasonable max limit.
//
// Then we read the signature and payload data. We compute the SHA256 checksum
// of the payload and verify that it matches the expected signature value.
//
// The last chunk is *always* 0-sized. So, we must only return io.EOF if we have encountered
// a chunk with a chunk size = 0. However, this chunk still has a signature and we must

	start := UTCNow()
	const readLock = false
	success := make([]int, len(li.paths))
	for i, path := range li.paths {
		if !li.ns.lock(ctx, li.volume, path, lockSource, li.opsID, readLock, timeout.Timeout()) {
			timeout.LogFailure()
			for si, sint := range success {
				if sint == 1 {
					li.ns.unlock(li.volume, li.paths[si], readLock)
				}
			}
			if errors.Is(ctx.Err(), context.Canceled) {

	}

	// Disallow relative paths, figure out absolute paths.
	dirAbs, err := filepath.Abs(dir)
	if err != nil {
		return nil, err
	}
	err = mkdirAllIgnorePerm(dirAbs)
	if err != nil {
		return nil, fmt.Errorf("unable to create the directory `%s`: %w", dirAbs, err)
	}

	return &ConfigDir{path: dirAbs}, nil
}