tlog.app/go/tlog@v0.23.1/convert/logfmt.go

package convert

import (
	"errors"
	"io"
	"path/filepath"
	"strconv"
	"time"

	"github.com/nikandfor/hacked/hfmt"
	"github.com/nikandfor/hacked/low"
	"golang.org/x/term"
	"tlog.app/go/loc"

	"tlog.app/go/tlog"
	tlow "tlog.app/go/tlog/low"
	"tlog.app/go/tlog/tlio"
	"tlog.app/go/tlog/tlwire"
)

type (
	Logfmt struct { //nolint:maligned
		io.Writer

		TimeFormat string
		TimeZone   *time.Location

		FloatFormat    string
		FloatChar      byte
		FloatPrecision int

		QuoteChars      string
		QuoteAnyValue   bool
		QuoteEmptyValue bool

		PairSeparator  string
		KVSeparator    string
		ArrSeparator   string
		MapSeparator   string
		MapKVSeparator string

		MaxValPad int

		AppendKeySafe bool
		SubObjects    bool

		Rename RenameFunc

		Colorize bool
		KeyColor []byte
		ValColor []byte

		d tlwire.Decoder

		b low.Buf

		addpad int
		pad    map[string]int
	}
)

func NewLogfmt(w io.Writer) *Logfmt {
	fd := tlio.Fd(w)
	colorize := term.IsTerminal(int(fd))

	return &Logfmt{
		Writer: w,

		TimeFormat:     "2006-01-02T15:04:05.000000000Z07:00",
		TimeZone:       time.Local,
		FloatChar:      'f',
		FloatPrecision: 5,
		QuoteChars:     "`\"' ()[]{}*",

		PairSeparator:  "  ",
		KVSeparator:    "=",
		ArrSeparator:   " ",
		MapSeparator:   " ",
		MapKVSeparator: "=",

		MaxValPad: 24,

		Colorize: colorize,
		KeyColor: tlog.Color(36),

		AppendKeySafe: true,

		pad: make(map[string]int),
	}
}

func (w *Logfmt) Write(p []byte) (i int, err error) {
	b := w.b[:0]

more:
	tag, els, i := w.d.Tag(p, i)
	if tag != tlwire.Map {
		return i, errors.New("map expected")
	}

	w.addpad = 0

	var k []byte
	for el := 0; els == -1 || el < int(els); el++ {
		if els == -1 && w.d.Break(p, &i) {
			break
		}

		k, i = w.d.Bytes(p, i)

		b, i = w.appendPair(b, p, k, i, el == 0)
	}

	b = append(b, '\n')

	if i < len(p) {
		goto more
	}

	w.b = b[:0]

	_, err = w.Writer.Write(b)
	if err != nil {
		return 0, err
	}

	return len(p), nil
}

func (w *Logfmt) appendPair(b, p, k []byte, st int, first bool) (_ []byte, i int) {
	if w.addpad != 0 {
		b = append(b, low.Spaces[:w.addpad]...)
		w.addpad = 0
	}

	if !w.SubObjects {
		tag := w.d.TagOnly(p, st)

		if tag == tlwire.Array || tag == tlwire.Map {
			return w.convertArray(b, p, k, st, first)
		}
	}

	if !first {
		b = append(b, w.PairSeparator...)
	}

	if w.Colorize && len(w.KeyColor) != 0 {
		b = append(b, w.KeyColor...)
	}

	var renamed bool

	if w.Rename != nil {
		b, renamed = w.Rename(b, p, k, st)
	}

	if !renamed {
		b = w.appendAndQuote(b, k, tlwire.String)
	}

	b = append(b, w.KVSeparator...)

	if w.Colorize && len(w.ValColor) != 0 {
		b = append(b, w.ValColor...)
	} else if w.Colorize && len(w.KeyColor) != 0 {
		b = append(b, tlog.ResetColor...)
	}

	vst := len(b)

	b, i = w.ConvertValue(b, p, k, st)

	vw := len(b) - vst

	// NOTE: Value width can be incorrect for non-ascii symbols.
	// We can calc it by iterating utf8.DecodeRune() but should we?

	if w.Colorize && len(w.ValColor) != 0 {
		b = append(b, tlog.ResetColor...)
	}

	nw := w.pad[tlow.UnsafeBytesToString(k)]

	if vw < nw {
		w.addpad = nw - vw
	}

	if nw < vw && vw <= w.MaxValPad {
		if vw > w.MaxValPad {
			vw = w.MaxValPad
		}

		w.pad[string(k)] = vw
	}

	return b, i
}

func (w *Logfmt) ConvertValue(b, p, k []byte, st int) (_ []byte, i int) {
	tag, sub, i := w.d.Tag(p, st)

	switch tag {
	case tlwire.Int:
		b = strconv.AppendUint(b, uint64(sub), 10)
	case tlwire.Neg:
		b = strconv.AppendInt(b, 1-sub, 10)
	case tlwire.Bytes, tlwire.String:
		var s []byte
		s, i = w.d.Bytes(p, st)

		b = w.appendAndQuote(b, s, tag)
	case tlwire.Array:
		b, i = w.convertArray(b, p, k, st, false)
	case tlwire.Map:
		b, i = w.convertArray(b, p, k, st, false)
	case tlwire.Semantic:
		switch sub {
		case tlwire.Time:
			var t time.Time
			t, i = w.d.Time(p, st)

			if w.TimeZone != nil {
				t = t.In(w.TimeZone)
			}

			if w.TimeFormat != "" {
				b = append(b, '"')
				b = t.AppendFormat(b, w.TimeFormat)
				b = append(b, '"')
			} else {
				b = strconv.AppendInt(b, t.UnixNano(), 10)
			}
		case tlog.WireID:
			var id tlog.ID
			i = id.TlogParse(p, st)

			bst := len(b) + 1
			b = append(b, `"12345678-9_12-3456-789_-123456789_12"`...)

			id.FormatTo(b, bst, 'u')
		case tlwire.Caller:
			var pc loc.PC
			var pcs loc.PCs
			pc, pcs, i = w.d.Callers(p, st)

			if pcs != nil {
				b = append(b, '[')
				for i, pc := range pcs {
					if i != 0 {
						b = append(b, ',')
					}

					_, file, line := pc.NameFileLine()
					b = hfmt.Appendf(b, `"%v:%d"`, filepath.Base(file), line)
				}
				b = append(b, ']')
			} else {
				_, file, line := pc.NameFileLine()

				b = hfmt.Appendf(b, `"%v:%d"`, filepath.Base(file), line)
			}
		default:
			b, i = w.ConvertValue(b, p, k, i)
		}
	case tlwire.Special:
		switch sub {
		case tlwire.False:
			b = append(b, "false"...)
		case tlwire.True:
			b = append(b, "true"...)
		case tlwire.Nil:
			b = append(b, "<nil>"...)
		case tlwire.Undefined:
			b = append(b, "<undef>"...)
		case tlwire.None:
			b = append(b, "<none>"...)
		case tlwire.Hidden:
			b = append(b, "<hidden>"...)
		case tlwire.SelfRef:
			b = append(b, "<self_ref>"...)
		case tlwire.Float64, tlwire.Float32, tlwire.Float8:
			var f float64
			f, i = w.d.Float(p, st)

			if w.FloatFormat != "" {
				b = hfmt.Appendf(b, w.FloatFormat, f)
			} else {
				b = strconv.AppendFloat(b, f, w.FloatChar, w.FloatPrecision, 64)
			}
		default:
			panic(sub)
		}
	default:
		panic(tag)
	}

	return b, i
}

func (w *Logfmt) appendAndQuote(b, s []byte, tag byte) []byte {
	quote := tag == tlwire.Bytes || w.QuoteAnyValue || len(s) == 0 && w.QuoteEmptyValue
	if !quote {
		for _, c := range s {
			if c < 0x20 || c >= 0x80 {
				quote = true
				break
			}
			for _, q := range w.QuoteChars {
				if byte(q) == c {
					quote = true
					break
				}
			}
		}
	}

	switch {
	case quote:
		ss := tlow.UnsafeBytesToString(s)
		b = strconv.AppendQuote(b, ss)
	case w.AppendKeySafe:
		b = tlow.AppendSafe(b, s)
	default:
		b = append(b, s...)
	}

	return b
}

func (w *Logfmt) convertArray(b, p, k []byte, st int, first bool) (_ []byte, i int) {
	tag, sub, i := w.d.Tag(p, st)

	subk := k[:len(k):len(k)]

	if w.SubObjects {
		if tag == tlwire.Map {
			b = append(b, '{')
		} else {
			b = append(b, '[')
		}
	}

	for el := 0; sub == -1 || el < int(sub); el++ {
		if sub == -1 && w.d.Break(p, &i) {
			break
		}

		if !w.SubObjects {
			if tag == tlwire.Map {
				var kk []byte

				kk, i = w.d.Bytes(p, i)

				subk = append(subk[:len(k)], '.')
				subk = append(subk, kk...)
			}

			b, i = w.appendPair(b, p, subk, i, first && el == 0)

			continue
		}

		if tag == tlwire.Map {
			if el != 0 {
				b = append(b, w.MapSeparator...)
			}

			k, i = w.d.Bytes(p, i)

			if w.AppendKeySafe {
				b = tlow.AppendSafe(b, k)
			} else {
				b = append(b, k...)
			}

			b = append(b, w.MapKVSeparator...)
		} else if el != 0 {
			b = append(b, w.ArrSeparator...)
		}

		b, i = w.ConvertValue(b, p, subk, i)
	}

	if w.SubObjects {
		if tag == tlwire.Map {
			b = append(b, '}')
		} else {
			b = append(b, ']')
		}
	}

	return b, i
}