"io"
	"os"
)

// This file contains the helper "MReader", a wrapper around bio plus
// an "mmap'd read-only" view of the file obtained from bio.SliceRO().
// MReader is designed to implement the io.ReaderSeeker interface.
// Since bio.SliceOS() is not guaranteed to succeed, MReader falls back
// on explicit reads + seeks provided by bio.Reader if needed.

type MReader struct {
	f        *os.File
	rdr      *bio.Reader

	// that correspond to it).
	BeginPod(p pods.Pod)
	EndPod(p pods.Pod)

	// Invoked when the reader is starting to examine the meta-data
	// file for a pod. Here 'mdf' is the path of the file, and 'mfr'
	// is an open meta-data reader.
	VisitMetaDataFile(mdf string, mfr *decodemeta.CoverageMetaFileReader)

	// Invoked when the reader processes a counter data file, first
	// the 'begin' method at the start, then the 'end' method when

	"runtime"
	"sync"

	"github.com/bcicen/jstream"
	"github.com/minio/minio/internal/s3select/sql"
)

// PReader - JSON record reader for S3Select.
// Operates concurrently on line-delimited JSON.
type PReader struct {
	args        *ReaderArgs
	readCloser  io.ReadCloser   // raw input
	buf         *bufio.Reader   // input to the splitter
	current     []jstream.KVS   // current block of results to be returned

	hdr := r.opts.HeaderSize // remaining header bytes
	var tokens int           // number of tokens to request

	if hdr > 0 { // available tokens go towards header first
		if hdr < b { // all of header can be accommodated
			r.opts.HeaderSize = 0
			need = int(math.Min(float64(b-hdr), float64(need))) // use remaining tokens towards payload
			tokens = need + hdr

		} else { // part of header can be accommodated
			r.opts.HeaderSize -= b - 1

	ErrHeader = errors.New("zlib: invalid header")
)

type reader struct {
	r            flate.Reader
	decompressor io.ReadCloser
	digest       hash.Hash32
	err          error
	scratch      [4]byte
}

// Resetter resets a ReadCloser returned by [NewReader] or [NewReaderDict]
// to switch to a new underlying Reader. This permits reusing a ReadCloser

)

// A Reader wraps an io.Reader and computes the MD5 checksum
// of the read content as ETag. Optionally, it also computes
// the SHA256 checksum of the content.
//
// If the reference values for the ETag and content SHA26
// are not empty then it will check whether the computed
// match the reference values.
type Reader struct {
	src         io.Reader
	bytesRead   int64
	expectedMin int64

}

// NewReader creates a new trace reader.
func NewReader(r io.Reader) (*Reader, error) {
	br := bufio.NewReader(r)
	v, err := version.ReadHeader(br)
	if err != nil {
		return nil, err
	}
	switch v {
	case version.Go111, version.Go119, version.Go121:
		tr, err := oldtrace.Parse(br, v)
		if err != nil {
			return nil, err
		}
		return &Reader{
			go121Events: convertOldFormat(tr),
		}, nil

	errTooMuch   = errors.New("gif: too much image data")
	errBadPixel  = errors.New("gif: invalid pixel value")
)

// If the io.Reader does not also have ReadByte, then decode will introduce its own buffering.
type reader interface {
	io.Reader
	io.ByteReader
}

// Masks etc.
const (
	// Fields.
	fColorTable         = 1 << 7
	fInterlace          = 1 << 6
	fColorTableBitsMask = 7

package strings

import (
	"errors"
	"io"
	"unicode/utf8"
)

// A Reader implements the [io.Reader], [io.ReaderAt], [io.ByteReader], [io.ByteScanner],
// [io.RuneReader], [io.RuneScanner], [io.Seeker], and [io.WriterTo] interfaces by reading
// from a string.
// The zero value for Reader operates like a Reader of an empty string.
type Reader struct {
	s        string
	i        int64 // current reading index

//
//	// Now, we need an io.Reader that can access
//	// the ETag computed over the content.
//	reader := etag.Wrap(encryptedContent, content)
func Wrap(wrapped, content io.Reader) io.Reader {
	if t, ok := content.(Tagger); ok {
		return wrapReader{
			Reader: wrapped,
			Tagger: t,
		}
	}
	return wrapReader{
		Reader: wrapped,
	}
}

// A Reader wraps an io.Reader and computes the