package logger

import (
	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
	"io"
	"os"
	"time"
)

const (
	// DebugLevel logs are typically voluminous, and are usually disabled in
	// production.
	DebugLevel = zapcore.DebugLevel
	// InfoLevel is the default logging priority.
	InfoLevel = zapcore.InfoLevel
	// WarnLevel logs are more important than Info, but don't need individual
	// human review.
	WarnLevel = zapcore.WarnLevel
	// ErrorLevel logs are high-priority. If an application is running smoothly,
	// it shouldn't generate any error-level logs.
	ErrorLevel = zapcore.ErrorLevel
	// DPanicLevel logs are particularly important errors. In development the
	// logger panics after writing the message.
	DPanicLevel = zapcore.DPanicLevel
	// PanicLevel logs a message, then panics.
	PanicLevel = zapcore.PanicLevel
	// FatalLevel logs a message, then calls os.Exit(1).
	FatalLevel = zapcore.FatalLevel
)

var (
	Logger = &logger{}

	LowercaseLevelEncoder      = zapcore.LowercaseLevelEncoder
	LowercaseColorLevelEncoder = zapcore.LowercaseColorLevelEncoder
	CapitalLevelEncoder        = zapcore.CapitalLevelEncoder
	CapitalColorLevelEncoder   = zapcore.CapitalColorLevelEncoder
)

type logger struct {
	*zap.Logger
	Config      *LoggerConfig
	hasShowLine bool
}

type LoggerConfig struct {
	Levels       []zapcore.Level      `json:"level"`
	ShowLine     bool                 `json:"showLine"`
	LogInConsole bool                 `json:"logInConsole"`
	Format       string               `json:"format"`
	EncodeLevel  zapcore.LevelEncoder `json:"encodeLevel"`
	Prefix       string               `json:"prefix"`
	Writer       func(config *LoggerConfig, filename string, level zapcore.Level) io.Writer
}

// InitLogger @Title 初始化日志工具
func InitLogger(config *LoggerConfig) *logger {
	Logger.Config = config

	Logger.Logger = zap.New(zapcore.NewTee(
		Logger.getEncoderCore("debug", zapcore.DebugLevel),
		Logger.getEncoderCore("info", zapcore.InfoLevel),
		Logger.getEncoderCore("Warn", zapcore.WarnLevel),
		Logger.getEncoderCore("error", zapcore.ErrorLevel),
	), zap.AddCaller())
	if config.ShowLine {
		Logger.Logger = Logger.Logger.WithOptions(zap.AddCaller())
	}
	return Logger
}

// getEncoderConfig 获取zapcore.EncoderConfig
func (l *logger) getEncoderConfig() (config zapcore.EncoderConfig) {
	config = zapcore.EncoderConfig{
		MessageKey:     "message",
		LevelKey:       "level",
		TimeKey:        "time",
		NameKey:        "logger",
		CallerKey:      "caller",
		LineEnding:     zapcore.DefaultLineEnding,
		EncodeLevel:    l.Config.EncodeLevel,
		EncodeTime:     l.CustomTimeEncoder,
		EncodeDuration: zapcore.SecondsDurationEncoder,
		EncodeCaller:   zapcore.FullCallerEncoder,
	}
	if config.EncodeLevel == nil {
		config.EncodeLevel = zapcore.LowercaseLevelEncoder
	}
	return config
}

// getEncoder 获取zapcore.Encoder
func (l *logger) getEncoder() zapcore.Encoder {
	if l.Config.Format == "json" {
		return zapcore.NewJSONEncoder(l.getEncoderConfig())
	}
	return zapcore.NewConsoleEncoder(l.getEncoderConfig())
}

// getEncoderCore 获取Encoder的zapcore.Core
func (l *logger) getEncoderCore(filename string, level zapcore.Level) (core zapcore.Core) {
	return zapcore.NewCore(l.getEncoder(), l.getWriteSyncer(filename, level), zap.LevelEnablerFunc(func(lvl zapcore.Level) bool {
		return l.inLevel(level) && lvl >= level
	}))
}

func (l *logger) inLevel(level zapcore.Level) bool {
	for _, cLevel := range l.Config.Levels {
		if cLevel == level {
			return true
		}
	}
	return false
}

// CustomTimeEncoder 自定义日志输出时间格式
func (l *logger) CustomTimeEncoder(t time.Time, enc zapcore.PrimitiveArrayEncoder) {
	enc.AppendString(t.Format(l.Config.Prefix + "2006/01/02 - 15:04:05.000"))
}

// @author: [piexlmax](https://github.com/piexlmax)
// @function: PathExists
// @description: 文件目录是否存在
// @param: path string
// @return: bool, error
func (l *logger) pathExists(path string) (bool, error) {
	_, err := os.Stat(path)
	if err == nil {
		return true, nil
	}
	if os.IsNotExist(err) {
		return false, nil
	}
	return false, err
}

func (l *logger) getWriteSyncer(filename string, level zapcore.Level) zapcore.WriteSyncer {
	var fileWriter io.Writer
	// 日志切割
	if l.Config.Writer != nil {
		fileWriter = l.Config.Writer(l.Config, filename, level)
	} else {
		return zapcore.AddSync(os.Stdout)
	}
	if l.Config.LogInConsole && !l.hasShowLine && l.inLevel(level) {
		l.hasShowLine = true
		return zapcore.NewMultiWriteSyncer(zapcore.AddSync(os.Stdout), zapcore.AddSync(fileWriter))
	}
	return zapcore.AddSync(fileWriter)
}