package zerolog

import (
	"encoding/json"
	"strconv"
	"sync/atomic"
	"time"
)

const (
	// TimeFormatUnix defines a time format that makes time fields to be
	// serialized as Unix timestamp integers.
	TimeFormatUnix = ""

	// TimeFormatUnixMs defines a time format that makes time fields to be
	// serialized as Unix timestamp integers in milliseconds.
	TimeFormatUnixMs = "UNIXMS"

	// TimeFormatUnixMicro defines a time format that makes time fields to be
	// serialized as Unix timestamp integers in microseconds.
	TimeFormatUnixMicro = "UNIXMICRO"
)

var (
	// TimestampFieldName is the field name used for the timestamp field.
	TimestampFieldName = "time"

	// LevelFieldName is the field name used for the level field.
	LevelFieldName = "level"

	// LevelTraceValue is the value used for the trace level field.
	LevelTraceValue = "trace"
	// LevelDebugValue is the value used for the debug level field.
	LevelDebugValue = "debug"
	// LevelInfoValue is the value used for the info level field.
	LevelInfoValue = "info"
	// LevelWarnValue is the value used for the warn level field.
	LevelWarnValue = "warn"
	// LevelErrorValue is the value used for the error level field.
	LevelErrorValue = "error"
	// LevelFatalValue is the value used for the fatal level field.
	LevelFatalValue = "fatal"
	// LevelPanicValue is the value used for the panic level field.
	LevelPanicValue = "panic"

	// LevelFieldMarshalFunc allows customization of global level field marshaling.
	LevelFieldMarshalFunc = func(l Level) string {
		return l.String()
	}

	// MessageFieldName is the field name used for the message field.
	MessageFieldName = "message"

	// ErrorFieldName is the field name used for error fields.
	ErrorFieldName = "error"

	// CallerFieldName is the field name used for caller field.
	CallerFieldName = "caller"

	// CallerSkipFrameCount is the number of stack frames to skip to find the caller.
	CallerSkipFrameCount = 2

	// CallerMarshalFunc allows customization of global caller marshaling
	CallerMarshalFunc = func(file string, line int) string {
		return file + ":" + strconv.Itoa(line)
	}

	// ErrorStackFieldName is the field name used for error stacks.
	ErrorStackFieldName = "stack"

	// ErrorStackMarshaler extract the stack from err if any.
	ErrorStackMarshaler func(err error) interface{}

	// ErrorMarshalFunc allows customization of global error marshaling
	ErrorMarshalFunc = func(err error) interface{} {
		return err
	}

	// InterfaceMarshalFunc allows customization of interface marshaling.
	// Default: "encoding/json.Marshal"
	InterfaceMarshalFunc = json.Marshal

	// TimeFieldFormat defines the time format of the Time field type. If set to
	// TimeFormatUnix, TimeFormatUnixMs or TimeFormatUnixMicro, the time is formatted as an UNIX
	// timestamp as integer.
	TimeFieldFormat = time.RFC3339

	// TimestampFunc defines the function called to generate a timestamp.
	TimestampFunc = time.Now

	// DurationFieldUnit defines the unit for time.Duration type fields added
	// using the Dur method.
	DurationFieldUnit = time.Millisecond

	// DurationFieldInteger renders Dur fields as integer instead of float if
	// set to true.
	DurationFieldInteger = false

	// ErrorHandler is called whenever zerolog fails to write an event on its
	// output. If not set, an error is printed on the stderr. This handler must
	// be thread safe and non-blocking.
	ErrorHandler func(err error)

	// DefaultContextLogger is returned from Ctx() if there is no logger associated
	// with the context.
	DefaultContextLogger *Logger
)

var (
	gLevel          = new(int32)
	disableSampling = new(int32)
)

// SetGlobalLevel sets the global override for log level. If this
// values is raised, all Loggers will use at least this value.
//
// To globally disable logs, set GlobalLevel to Disabled.
func SetGlobalLevel(l Level) {
	atomic.StoreInt32(gLevel, int32(l))
}

// GlobalLevel returns the current global log level
func GlobalLevel() Level {
	return Level(atomic.LoadInt32(gLevel))
}

// DisableSampling will disable sampling in all Loggers if true.
func DisableSampling(v bool) {
	var i int32
	if v {
		i = 1
	}
	atomic.StoreInt32(disableSampling, i)
}

func samplingDisabled() bool {
	return atomic.LoadInt32(disableSampling) == 1
}