// Copyright(C) 2021. Huawei Technologies Co.,Ltd. All rights reserved.

// Package hwlog provides the capability of processing Huawei log rules.
package hwlog

import (
"bytes"
"context"
"fmt"
"go.uber.org/zap"
"runtime"
"strings"
)

// printHelper helper function for log printing
func printHelper(f func(string, …zap.Field), msg string, ctx …context.Context) {
str := getCallerInfo(ctx…)
f(str + msg)
}

// getCallerInfo gets the caller's information
func getCallerInfo(ctx …context.Context) string {
var deep = stackDeep
var userID interface{}
var traceID interface{}
for _, c := range ctx {
if c == nil {
deep++
continue
}
userID = c.Value(UserID)
traceID = c.Value(ReqID)
}
var funcName string
pc, codePath, codeLine, ok := runtime.Caller(deep)
if ok {
funcName = runtime.FuncForPC(pc).Name()
}
p := strings.Split(codePath, "/")
l := len(p)
if l == pathLen {
funcName = p[l-1]
} else if l > pathLen {
funcName = fmt.Sprintf("%s/%s", p[l-pathLen], p[l-1])
}
callerPath := fmt.Sprintf("%s:%d", funcName, codeLine)
goroutineID := getGoroutineID()
str := fmt.Sprintf("%-8s%s ", goroutineID, callerPath)
if userID != nil || traceID != nil {
str = fmt.Sprintf("%s{%v}-{%v} ", str, userID, traceID)
}
return str
}

// getCallerGoroutineID gets the goroutineID
func getGoroutineID() string {
b := make([]byte, bitsize, bitsize)
b = b[:runtime.Stack(b, false)]
b = bytes.TrimPrefix(b, []byte("goroutine "))
b = b[:bytes.IndexByte(b, ' ')]
return string(b)
}