package log

import (
	"context"
	"fmt"
	"os"
	"path/filepath"
	"runtime"
	"time"

	"github.com/rs/zerolog"
	"gopkg.in/natefinch/lumberjack.v2"
)

type LogType string

const (
	TypeAccess   LogType = "access"
	TypeBusiness LogType = "business"
	TypeError    LogType = "error"
)

var (
	logger zerolog.Logger
)

// Setup 初始化日志配置
func Setup(conf LogConfig) error {
	// 确保日志目录存在
	if err := os.MkdirAll(filepath.Dir(conf.OutputPath), 0755); err != nil {
		return fmt.Errorf("create log directory failed: %v", err)
	}

	// 配置日志轮转
	writer := &lumberjack.Logger{
		Filename:   conf.OutputPath,
		MaxSize:    conf.MaxSize, // MB
		MaxAge:     conf.MaxAge,  // days
		MaxBackups: conf.MaxBackups,
		Compress:   conf.Compress,
	}

	// 设置日志级别
	level, err := zerolog.ParseLevel(conf.Level)
	if err != nil {
		level = zerolog.InfoLevel
	}
	zerolog.SetGlobalLevel(level)

	// 初始化logger 并添加 app_name
	logger = zerolog.New(writer).With().
		Timestamp().
		Str("app_name", conf.AppName). // 添加 app_name
		Logger()

	return nil
}

// log 统一的日志记录函数
func log(ctx context.Context, level zerolog.Level, logType LogType, kv ...interface{}) {
	if len(kv)%2 != 0 {
		kv = append(kv, "MISSING")
	}

	event := logger.WithLevel(level)

	// 添加日志类型
	event.Str("type", string(logType))

	// 添加请求ID
	if reqID, exists := ctx.Value("request_id").(string); exists {
		event.Str("request_id", reqID)
	}

	// 添加调用位置
	if pc, file, line, ok := runtime.Caller(2); ok {
		event.Str("caller", fmt.Sprintf("%s:%d %s", filepath.Base(file), line, runtime.FuncForPC(pc).Name()))
	}

	// 处理key-value对
	for i := 0; i < len(kv); i += 2 {
		key, ok := kv[i].(string)
		if !ok {
			continue
		}
		value := kv[i+1]

		switch v := value.(type) {
		case error:
			event.AnErr(key, v)
		case int:
			event.Int(key, v)
		case int64:
			event.Int64(key, v)
		case float64:
			event.Float64(key, v)
		case bool:
			event.Bool(key, v)
		case time.Duration:
			event.Dur(key, v)
		case time.Time:
			event.Time(key, v)
		case []byte:
			event.Bytes(key, v)
		case string:
			event.Str(key, v)
		default:
			event.Interface(key, v)
		}
	}

	event.Send()
}

// Debug 记录调试日志
func Debug(ctx context.Context, kv ...interface{}) {
	log(ctx, zerolog.DebugLevel, TypeBusiness, kv...)
}

// Info 记录信息日志
func Info(ctx context.Context, kv ...interface{}) {
	log(ctx, zerolog.InfoLevel, TypeBusiness, kv...)
}

// Warn 记录警告日志
func Warn(ctx context.Context, kv ...interface{}) {
	log(ctx, zerolog.WarnLevel, TypeError, kv...)
}

// Error 记录错误日志
func Error(ctx context.Context, kv ...interface{}) {
	log(ctx, zerolog.ErrorLevel, TypeError, kv...)
}

func Fatal(ctx context.Context, kv ...interface{}) {
	// 获取错误堆栈
	buf := make([]byte, 4096)
	n := runtime.Stack(buf, false)

	// 添加堆栈信息到kv
	newKv := make([]interface{}, 0, len(kv)+2)
	newKv = append(newKv, kv...)
	newKv = append(newKv, "stack", string(buf[:n]))

	log(ctx, zerolog.FatalLevel, TypeError, newKv...)
}

// Access 记录访问日志
func Access(ctx context.Context, kv ...interface{}) {
	log(ctx, zerolog.InfoLevel, TypeAccess, kv...)
}