debug.go

package debug

import (
	"bufio"
	"bytes"
	"fmt"
	"go/token"
	"os"
	"runtime"
	"strings"
	"time"
)

const (
	delimiterBeg string = `[ %02d.%02d.%04d %02d:%02d:%02d:%010d ] ------------------------------------------------------------`
	delimiterEnd string = `-----------------------------------------------------------------------------------------------`
	lineEnd      string = "\n"
	lineEndCRLF  string = "\r\n"
)

var (
	defaultCRLF bool // For operating systems with the end of line CRLF or set environment value DEBUG_CRLF=true or DEBUG_CRLF=false
	seeCalls    bool // Search on a large project forgotten debug calls. Set to true by environment value DEBUG_CALLS=true
	seeTrace    bool // Printing with the bump data call stack. Set to true by set environment value DEBUG_TRACESTACK=true
)

type debug struct {
	Result     *bytes.Buffer
	Buffer     *bytes.Buffer
	ReadWriter *bufio.ReadWriter
	UseCRLF    bool
	Now        time.Time
	Trace      *trace
}

func init() {
	const (
		false      = `false`
		windows    = `windows`
		calls      = `DEBUG_CALLS`
		crlf       = `DEBUG_CRLF`
		tracestack = `DEBUG_TRACESTACK`
	)

	switch runtime.GOOS {
	case windows:
		defaultCRLF = true
	}
	if os.Getenv(calls) != "" {
		if strings.EqualFold(os.Getenv(calls), false) != true {
			seeCalls = true
		}
	}
	if os.Getenv(crlf) != "" {
		if strings.EqualFold(os.Getenv(crlf), false) != true {
			defaultCRLF = true
		}
	}
	if os.Getenv(tracestack) != "" {
		if strings.EqualFold(os.Getenv(tracestack), false) != true {
			seeTrace = true
		}
	}
}

func newDebug() (obj *debug) {
	var buf = &bytes.Buffer{}

	obj = &debug{
		Result:     &bytes.Buffer{},
		Buffer:     buf,
		ReadWriter: bufio.NewReadWriter(bufio.NewReader(buf), bufio.NewWriter(buf)),
		UseCRLF:    defaultCRLF,
		Now:        time.Now().In(time.Local),
		Trace:      newTrace().Trace(traceStepBack + 1),
	}

	return
}

// Dump all variables
func (d *debug) Dump(idl ...interface{}) *debug {
	var (
		i    int
		fset *token.FileSet
	)

	for i = range idl {
		fset = token.NewFileSet()
		_ = printerPrint(d.ReadWriter, fset, idl[i], notNilFilter)
	}
	// call stack
	if seeTrace {
		_, _ = d.ReadWriter.WriteString(d.Trace.Stack + lineEnd)
	}

	return d
}

// Add information before dump
func (d *debug) Prefix(fn string) *debug {
	_, _ = d.ReadWriter.WriteString(fmt.Sprintf(delimiterBeg+lineEnd, d.Now.Day(), d.Now.Month(), d.Now.Year(), d.Now.Hour(), d.Now.Minute(), d.Now.Second(), d.Now.Nanosecond()))
	_, _ = d.ReadWriter.WriteString(fmt.Sprintf("[ %30s ] %s:%d [%s] [%s()]"+lineEnd, fn, d.Trace.File, d.Trace.Line, d.Trace.Package, d.Trace.Function))

	return d
}

// Add information after dump
func (d *debug) Suffix() *debug {
	_, _ = d.ReadWriter.WriteString(delimiterEnd + lineEnd)

	return d
}

// Finalisation dump
func (d *debug) Final() *bytes.Buffer {
	var (
		line     []byte
		isPrefix bool
		err      error
	)

	_ = d.ReadWriter.Flush()
	for {
		line, isPrefix, err = d.ReadWriter.ReadLine()
		_, _ = d.Result.Write(line)
		if isPrefix {
			continue
		}
		if len(line) > 0 {
			if d.UseCRLF {
				_, _ = d.Result.WriteString(lineEndCRLF)
			} else {
				_, _ = d.Result.WriteString(lineEnd)
			}
		}
		if err != nil {
			break
		}
	}

	return d.Result
}