// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
package log

import (
	"bytes"
	"encoding/json"
	"fmt"
	"log"
	"os"
	"path/filepath"
	"runtime"
	"runtime/debug"
	"strings"
	"sync"
	"time"

	"qoobing.com/gomod/str"
)

var (
	glogger     *log.Logger        = nil
	once        sync.Once          = sync.Once{}
	mylogger    *Logger            = nil
	modulelogs  map[string]*Logger = map[string]*Logger{}
	logidSetter func(string)       = nil
	logidGetter func() string      = nil
)

const ErrLogPanic = "~~~~panic~~~~~~"

//////////////global log//////////////////begin///////////////////
func SetLogLevel(newlv logLevel) (oldlv logLevel) {
	return mylogger.SetLogLevel(newlv)
}
func PrintPretty(prefix string, v interface{}) {
	mylogger.PrintPretty(prefix, v)
}
func DebugfWithDepth(calldepth int, format string, v ...interface{}) {
	mylogger.DebugfWithDepth(calldepth, format, v...)
}
func Debugf(format string, v ...interface{}) {
	mylogger.Debugf(format, v...)
}
func Noticef(format string, v ...interface{}) {
	mylogger.Noticef(format, v...)
}
func NoticefWithDepth(calldepth int, format string, v ...interface{}) {
	mylogger.NoticefWithDepth(calldepth, format, v...)
}
func Infof(format string, v ...interface{}) {
	mylogger.Infof(format, v...)
}
func Warningf(format string, v ...interface{}) {
	mylogger.Warningf(format, v...)
}
func Errorf(format string, v ...interface{}) {
	mylogger.Warningf(format, v...)
}
func Panicf(format string, v ...interface{}) {
	mylogger.Panicf(format, v...)
}
func Fatalf(format string, v ...interface{}) {
	mylogger.Fatalf(format, v...)
}

//////////////////////////////////////////////////////////////////

type logLevel int

const (
	PANIC   logLevel = 0
	FATAL   logLevel = 1
	ERROR   logLevel = 2
	NOTICE  logLevel = 3
	WARNING logLevel = 4
	INFO    logLevel = 5
	DEBUG   logLevel = 9
)

type Logger struct {
	module   string
	loglevel logLevel
	logger   *log.Logger
}

func New(module string) (logger *Logger) {
	if module == "" {
		module = "undefine"
	}
	if _, ok := modulelogs[module]; ok {
		return modulelogs[module]
	} else {
		modulelogs[module] = &Logger{
			module:   module,
			logger:   glogger,
			loglevel: DEBUG,
		}
		return modulelogs[module]
	}
}

func (log *Logger) SetLogLevel(newlv logLevel) (oldlv logLevel) {
	oldlv = log.loglevel
	log.loglevel = newlv
	return oldlv
}

func (log *Logger) Print(prefix string, v interface{}) {
	preety, _ := json.Marshal(v)
	log.logwrite(DEBUG, 3, prefix+"%s\n", preety)
}

func (log *Logger) PrintPretty(prefix string, v interface{}) {
	preety, _ := json.MarshalIndent(v, "==", "    ")
	log.logwrite(DEBUG, 3, prefix+"%s\n", preety)
}

func (log *Logger) Debugf(format string, v ...interface{}) {
	log.logwrite(DEBUG, 3, format, v...)
}

func (log *Logger) DebugfWithDepth(calldepth int, format string, v ...interface{}) {
	calldepth += 3
	log.logwrite(DEBUG, calldepth, format, v...)
}

func (log *Logger) Noticef(format string, v ...interface{}) {
	log.logwrite(NOTICE, 3, format, v...)
}

func (log *Logger) NoticefWithDepth(calldepth int, format string, v ...interface{}) {
	calldepth += 3
	log.logwrite(NOTICE, calldepth, format, v...)
}

func (log *Logger) Warningf(format string, v ...interface{}) {
	log.logwrite(WARNING, 3, format, v...)
}

func (log *Logger) Infof(format string, v ...interface{}) {
	log.logwrite(INFO, 3, format, v...)
}

func (log *Logger) Errorf(format string, v ...interface{}) {
	log.logwrite(ERROR, 3, format, v...)
}

func (log *Logger) Fatalf(format string, v ...interface{}) {
	log.logwrite(FATAL, 3, format, v...)
}

func (log *Logger) Panicf(format string, v ...interface{}) {
	log.logwrite(PANIC, 3, format, v...)
}

func GetLogid() string {
	if logidGetter != nil {
		return logidGetter()
	}
	return ""
}

func SetLogid(logid string) {
	if logidSetter != nil {
		logidSetter(logid)
	}
}

func (log *Logger) logwrite(typ logLevel, calldepth int, format string, v ...interface{}) {
	if typ > log.loglevel {
		return
	}

	var idstr = ""
	if id := GetLogid(); id != "" {
		idstr = "[" + id + "] "
	}

	format = strings.Trim(format, "\n")
	switch typ {
	case PANIC:
		log.logger.SetPrefix("\x1b[31m" + "PANIC " + idstr + "[" + log.module + "] ")
	case FATAL:
		log.logger.SetPrefix("\x1b[31m" + "FATAL " + idstr + "[" + log.module + "] ")
	case WARNING:
		log.logger.SetPrefix("\x1b[32m" + "WARNING " + idstr + "[" + log.module + "] ")
	case ERROR:
		log.logger.SetPrefix("\x1b[32m" + "ERROR " + idstr + "[" + log.module + "] ")
	case INFO:
		log.logger.SetPrefix("INFO " + idstr + "[" + log.module + "] ")
	case NOTICE:
		log.logger.SetPrefix("NOTICE " + idstr + "[" + log.module + "] ")
	case DEBUG:
		log.logger.SetPrefix("DEBUG " + idstr + "[" + log.module + "] ")
	default:
		log.logger.SetPrefix("UNKNOWN " + idstr + "[" + log.module + "] ")
	}

	if mylogger == log {
		calldepth = calldepth + 1
	}

	if typ == FATAL || typ == WARNING || typ == ERROR {
		log.logger.Output(calldepth, fmt.Sprintf(format+"\x1b[0m\n", v...))
	} else if typ == NOTICE {
		calldepth = calldepth + 2
		log.logger.Output(calldepth, fmt.Sprintf(format+"\n", v...))
	} else if typ == PANIC {
		stack := strings.Replace(string(debug.Stack()), "\n", "\n==    ", -1)
		stack = str.SkipLine(stack, calldepth*2+1)
		v = append(v, stack)
		panicstr := fmt.Sprintf(format+"\x1b[0m. Panic stack:\n%s\n", v...)
		log.logger.Output(calldepth, panicstr)
		panic(ErrLogPanic)
	} else {
		log.logger.Output(calldepth, fmt.Sprintf(format+"\n", v...))
	}
}

//////////////global log trace//////////////////begin///////////////////

func TRACE_INTO(format string, v ...interface{}) string {
	_, fn, line, _ := runtime.Caller(1)
	strfn := fmt.Sprintf("%s:%d", fn, line)
	Debugf("TRACE into ["+strfn+"]"+format+"...\r\n", v...)

	return strfn
}

func TRACE_EXIT(strfn string, format string, v ...interface{}) {
	Debugf("TRACE exit ["+strfn+"]"+format+"...\r\n", v...)
}

type mWriter struct {
	logw *os.File
	stdw *os.File
}

func (w mWriter) Write(p []byte) (n int, err error) {
	if flagcachelog {
		logCache.Write(p)
	}
	w.stdw.Write(p)
	return w.logw.Write(p)
}

var cacheLogLock = new(sync.Mutex)
var flagcachelog = false
var logCache = bytes.Buffer{}

func StartCacheLog() {
	cacheLogLock.Lock()
	flagcachelog = true
	logCache.Reset()
}
func StopCacheLog() {
	cacheLogLock.Unlock()
	flagcachelog = false
}
func GetCacheLog() string {
	if flagcachelog != true {
		panic("GetCacheLog MUST call after StartCacheLog called")
	}
	return logCache.String()
}

////////////////////////////////////////////////////////////////////////////////////
/////////////////////////Initialize/////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////
func init() {
	once.Do(initlog)
}

func initlog() {
	var mwriter mWriter
	var openlog = func(logname string) *log.Logger {
		fp, err := os.OpenFile(logname, os.O_APPEND|os.O_CREATE|os.O_WRONLY, os.ModePerm)
		if err != nil {
			panic("open log file failed:" + err.Error())
		}
		mwriter.logw.Close()
		mwriter.logw = fp
		mwriter.stdw = os.Stdout
		glogger = log.New(mwriter, "", log.Ldate|log.Lmicroseconds|log.Lshortfile)
		return glogger
	}

	_, logfilename := filepath.Split(os.Args[0])
	LOGSPLITTIME := "20060102" //20060102150405
	LOGFILENAME := logfilename + ".log"
	if _, err := os.Stat("log/"); err == nil {
		LOGFILENAME = "log/" + LOGFILENAME
	} else if _, err := os.Stat("logs/"); err == nil {
		LOGFILENAME = "logs/" + LOGFILENAME
	} else {
		LOGFILENAME = "logs/" + LOGFILENAME
	}

	glogger = openlog(LOGFILENAME)
	mylogger = New("system")
	curhourtime := time.Now().Local().Format(LOGSPLITTIME)
	prehourtime := curhourtime

	go func() {
		intva := 2 * time.Minute
		timer := time.NewTimer(1 * time.Second)

		for {
			select {
			case <-timer.C:
				curhourtime := time.Now().Local().Format(LOGSPLITTIME)
				//Debugf("check logfile: prehourtime:%s,curhourtime:%s", prehourtime, curhourtime)
				if prehourtime != curhourtime {
					// close old logger & move log to backup file.
					PREFILENAME := LOGFILENAME + "." + prehourtime
					os.Rename(LOGFILENAME, PREFILENAME)
					prehourtime = curhourtime

					glogger = openlog(LOGFILENAME)
					mylogger = New("system")
					for _, l := range modulelogs {
						l.logger = glogger
					}
				}

				timer.Reset(intva)
			}
		}
	}()
}