package memory

import (
	"errors"
	"github.com/patrickmn/go-cache"
	"meow.tf/go/cacheinterface/v2/encoder"
	"reflect"
	"time"
)

var (
	ErrNotExist = errors.New("item does not exist")
)

type Options struct {
	Encoder           encoder.Encoder `default:"msgpack"`
	DefaultExpiration time.Duration   `query:"defaultExpiration" default:"1m"`
	CleanupTime       time.Duration   `query:"cleanupTime" default:"5m"`
}

type Cache struct {
	options Options
	c       *cache.Cache
}

func New(options Options) (*Cache, error) {
	c := cache.New(options.DefaultExpiration, options.CleanupTime)

	return &Cache{
		options: options,
		c:       c,
	}, nil
}

func (mc *Cache) Has(key string) bool {
	_, exists := mc.c.Get(key)

	return exists
}

func (mc *Cache) Get(key string, dst any) error {
	item, exists := mc.c.Get(key)

	if !exists {
		return ErrNotExist
	}

	return CacheGet(item, dst)
}

func (mc *Cache) GetBytes(key string) ([]byte, error) {
	item, exists := mc.c.Get(key)

	if !exists {
		return nil, ErrNotExist
	}

	return CacheGetBytes(mc.options.Encoder, item)
}

func (mc *Cache) Set(key string, val any, ttl time.Duration) error {
	mc.c.Set(key, val, ttl)
	return nil
}

func (mc *Cache) Del(key string) error {
	mc.c.Delete(key)
	return nil
}

func CacheGetBytes(encoder encoder.Encoder, item any) ([]byte, error) {
	switch item.(type) {
	case string:
		return []byte(item.(string)), nil
	case []byte:
		return item.([]byte), nil
	}

	return encoder.Marshal(item)
}

func CacheGet(item any, v any) error {
	switch v := v.(type) {
	case *string:
		if v != nil {
			*v = item.(string)
			return nil
		}
	case *[]byte:
		if v != nil {
			*v = item.([]byte)
			return nil
		}
	case *int:
		if v != nil {
			*v = item.(int)
			return nil
		}
	case *int8:
		if v != nil {
			*v = item.(int8)
			return nil
		}
	case *int16:
		if v != nil {
			*v = item.(int16)
			return nil
		}
	case *int32:
		if v != nil {
			*v = item.(int32)
			return nil
		}
	case *int64:
		if v != nil {
			*v = item.(int64)
			return nil
		}
	case *uint:
		if v != nil {
			*v = item.(uint)
			return nil
		}
	case *uint8:
		if v != nil {
			*v = item.(uint8)
			return nil
		}
	case *uint16:
		if v != nil {
			*v = item.(uint16)
			return nil
		}
	case *uint32:
		if v != nil {
			*v = item.(uint32)
			return nil
		}
	case *uint64:
		if v != nil {
			*v = item.(uint64)
			return nil
		}
	case *bool:
		if v != nil {
			*v = item.(bool)
			return nil
		}
	case *float32:
		if v != nil {
			*v = item.(float32)
			return nil
		}
	case *float64:
		if v != nil {
			*v = item.(float64)
			return nil
		}
	case *[]string:
		*v = item.([]string)
		return nil
	case *map[string]string:
		*v = item.(map[string]string)
		return nil
	case *map[string]any:
		*v = item.(map[string]any)
		return nil
	case *time.Duration:
		if v != nil {
			*v = item.(time.Duration)
			return nil
		}
	case *time.Time:
		if v != nil {
			*v = item.(time.Time)
			return nil
		}
	}

	vv := reflect.ValueOf(v)

	if !vv.IsValid() {
		return errors.New("dst pointer is not valid")
	}

	if vv.Kind() != reflect.Ptr {
		return errors.New("dst pointer is not a pointer")
	}

	vv = vv.Elem()

	if !vv.IsValid() {
		return errors.New("dst pointer is not a valid element")
	}

	vv.Set(reflect.ValueOf(item))

	return nil
}