package log

import (
	"fmt"
	"os"
	"time"

	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
	"gopkg.in/natefinch/lumberjack.v2"
)

var sugar *zap.SugaredLogger

type Config struct {
	Path       string
	InfoFile   string
	ErrorFile  string
	FatalFile  string
	MaxSize    int
	MaxBackups int
	MaxAge     int
}

func Init(c Config) error {
	l, err := New(c)
	if err != nil {
		return err
	}
	sugar = l
	return nil
}

func Info(args ...any)                    { sugar.Info(args...) }
func Infof(template string, args ...any)  { sugar.Infof(template, args...) }
func Warn(args ...any)                    { sugar.Warn(args...) }
func Warnf(template string, args ...any)  { sugar.Warnf(template, args...) }
func Error(args ...any)                   { sugar.Error(args...) }
func Errorf(template string, args ...any) { sugar.Errorf(template, args...) }
func Fatal(args ...any)                   { sugar.Fatal(args...) }
func Fatalf(template string, args ...any) { sugar.Fatalf(template, args...) }

func New(c Config) (*zap.SugaredLogger, error) {
	if c.Path == "" {
		c.Path = "logs"
	}
	if c.InfoFile == "" {
		c.InfoFile = "info.log"
	}
	if c.ErrorFile == "" {
		c.ErrorFile = "error.log"
	}
	if c.FatalFile == "" {
		c.FatalFile = "fatal.log"
	}
	if c.MaxSize == 0 {
		c.MaxSize = 100
	}
	if c.MaxBackups == 0 {
		c.MaxBackups = 10
	}
	if c.MaxAge == 0 {
		c.MaxAge = 30
	}

	if err := os.MkdirAll(c.Path, 0o755); err != nil {
		return nil, fmt.Errorf("log mkdir: %w", err)
	}

	consoleEncoder := zapcore.NewConsoleEncoder(zapcore.EncoderConfig{
		MessageKey:  "msg",
		LevelKey:    "level",
		EncodeLevel: zapcore.LowercaseColorLevelEncoder,
		TimeKey:     "ts",
		EncodeTime: func(t time.Time, enc zapcore.PrimitiveArrayEncoder) {
			enc.AppendString(t.Format("2006-01-02 15:04:05"))
		},
		CallerKey:    "file",
		EncodeCaller: zapcore.ShortCallerEncoder,
		EncodeDuration: func(d time.Duration, enc zapcore.PrimitiveArrayEncoder) {
			enc.AppendInt64(int64(d) / 1e6)
		},
	})

	fileEncoder := zapcore.NewConsoleEncoder(zapcore.EncoderConfig{
		MessageKey:  "msg",
		LevelKey:    "level",
		EncodeLevel: zapcore.LowercaseLevelEncoder,
		TimeKey:     "ts",
		EncodeTime: func(t time.Time, enc zapcore.PrimitiveArrayEncoder) {
			enc.AppendString(t.Format("2006-01-02 15:04:05"))
		},
		CallerKey:    "file",
		EncodeCaller: zapcore.ShortCallerEncoder,
		EncodeDuration: func(d time.Duration, enc zapcore.PrimitiveArrayEncoder) {
			enc.AppendInt64(int64(d) / 1e6)
		},
	})

	infoLevel := zap.LevelEnablerFunc(func(lvl zapcore.Level) bool {
		return lvl == zapcore.InfoLevel
	})
	errorLevel := zap.LevelEnablerFunc(func(lvl zapcore.Level) bool {
		return lvl == zapcore.ErrorLevel
	})
	fatalLevel := zap.LevelEnablerFunc(func(lvl zapcore.Level) bool {
		return lvl == zapcore.FatalLevel
	})

	today := time.Now().Format("2006-01-02")
	infoWriter := getWriter(c.Path+"/"+today+"-"+c.InfoFile, c)
	errorWriter := getWriter(c.Path+"/"+today+"-"+c.ErrorFile, c)
	fatalWriter := getWriter(c.Path+"/"+today+"-"+c.FatalFile, c)

	core := zapcore.NewTee(
		zapcore.NewCore(consoleEncoder, zapcore.AddSync(os.Stdout), zap.LevelEnablerFunc(func(lvl zapcore.Level) bool {
			return lvl >= zapcore.InfoLevel
		})),
		zapcore.NewCore(fileEncoder, infoWriter, infoLevel),
		zapcore.NewCore(fileEncoder, errorWriter, errorLevel),
		zapcore.NewCore(fileEncoder, fatalWriter, fatalLevel),
	)

	// AddCallerSkip(1)：经包级 Info/Errorf 转发时显示真实调用方
	return zap.New(core, zap.AddCaller(), zap.AddCallerSkip(1)).Sugar(), nil
}

func getWriter(filename string, c Config) zapcore.WriteSyncer {
	return zapcore.AddSync(&lumberjack.Logger{
		Filename:   filename,
		MaxSize:    c.MaxSize,
		MaxBackups: c.MaxBackups,
		MaxAge:     c.MaxAge,
		Compress:   false,
		LocalTime:  true,
	})
}