package common

import (
	"math"
	"time"

	humanize "github.com/dustin/go-humanize"

	"strconv"
	"strings"

	"github.com/NyaaPantsu/nyaa/config"
	catUtil "github.com/NyaaPantsu/nyaa/util/categories"
)

type Status uint8

const (
	ShowAll Status = 0
	FilterRemakes = 2
	Trusted = 3
	APlus = 4
)

func (st *Status) ToString() string {
	switch *st {
	case FilterRemakes:
		return "2"
	case Trusted:
		return "3"
	case APlus:
		return "4"
	}
	return ""
}

func (st *Status) Parse(s string) {
	switch s {
	case "2":
		*st = FilterRemakes
	case "3":
		*st = Trusted
	case "4":
		*st = APlus
	default:
		*st = ShowAll
	}
}

type SortMode uint8

const (
	ID SortMode = iota
	Name
	Date
	Downloads
	Size
	Seeders
	Leechers
	Completed
)

func (s *SortMode) Parse(str string) {
	switch str {
	case "1":
		*s = Name
	case "2":
		*s = Date
	case "3":
		*s = Downloads
	case "4":
		*s = Size
	case "5":
		*s = Seeders
	case "6":
		*s = Leechers
	case "7":
		*s = Completed
	default:
		*s = Date
	}
}

/* INFO Always need to keep in sync with the field that are used in the
 * elasticsearch index.
 * TODO Verify the field in postgres database
 */
func (s *SortMode) ToESField() string {
	switch *s {
	case ID:
		return "id"
	case Name:
		return "name.raw"
	case Date:
		return "date"
	case Downloads:
		return "downloads"
	case Size:
		return "filesize"
	case Seeders:
		return "seeders"
	case Leechers:
		return "leechers"
	case Completed:
		return "completed"
	}
	return "id"
}

func (s *SortMode) ToDBField() string {
	switch *s {
	case ID:
		return "torrent_id"
	case Name:
		return "torrent_name"
	case Date:
		return "date"
	case Downloads:
		return "downloads"
	case Size:
		return "filesize"
	case Seeders:
		return "seeders"
	case Leechers:
		return "leechers"
	case Completed:
		return "completed"
	}
	return config.Conf.Torrents.Order
}

type Category struct {
	Main, Sub uint8
}

func (c Category) String() (s string) {
	if c.Main != 0 {
		s += strconv.Itoa(int(c.Main))
	}
	s += "_"
	if c.Sub != 0 {
		s += strconv.Itoa(int(c.Sub))
	}
	return
}

func (c Category) IsSet() bool {
	return c.IsMainSet() && c.IsSubSet()
}

func (c Category) IsMainSet() bool {
	return c.Main != 0
}

func (c Category) IsSubSet() bool {
	return c.Sub != 0
}

// Parse sets category by string
// returns true if string is valid otherwise returns false
func ParseCategories(s string) []*Category {
	if s != "" {
		parts := strings.Split(s, ",")
		var categories []*Category
		for _, val := range parts {
			partsCat := strings.Split(val, "_")
			if len(partsCat) == 2 {
				tmp, err := strconv.ParseUint(partsCat[0], 10, 8)
				if err == nil {
					c := uint8(tmp)
					tmp, err = strconv.ParseUint(partsCat[1], 10, 8)
					var sub uint8
					if err == nil {
						sub = uint8(tmp)
					}
					if catUtil.CategoryExists(partsCat[0] + "_" + partsCat[1]) {
						categories = append(categories, &Category{
							Main: c,
							Sub:  sub,
						})
					}
				}
			}
		}
		return categories
	}
	return Categories{}
}

type SizeBytes uint64

func (sz *SizeBytes) Parse(s string, sizeType string) bool {
	if s == "" {
		*sz = 0
		return false
	}
	var multiplier uint64
	switch sizeType {
	case "b":
		multiplier = 1
	case "k":
		multiplier = uint64(math.Exp2(10))
	case "m":
		multiplier = uint64(math.Exp2(20))
	case "g":
		multiplier = uint64(math.Exp2(30))
	}
	size64, err := humanize.ParseBytes(s)
	if err != nil {
		*sz = 0
		return false
	}
	*sz = SizeBytes(size64 * multiplier)
	return true
}

type DateFilter string

func (d *DateFilter) Parse(s string, dateType string) bool {
	if s == "" {
		*d = ""
		return false
	}
	dateInt, err := strconv.Atoi(s)
	if err != nil {
		*d = ""
		return false
	}
	switch dateType {
	case "m":
		*d = DateFilter(time.Now().AddDate(0, -dateInt, 0).Format("2006-01-02"))
	case "y":
		*d = DateFilter(time.Now().AddDate(-dateInt, 0, 0).Format("2006-01-02"))
	default:
		*d = DateFilter(time.Now().AddDate(0, 0, -dateInt).Format("2006-01-02"))
	}
	return true
}

type Categories []*Category

// deprecated for TorrentParam
type SearchParam struct {
	TorrentID uint
	FromID    uint // Search for torrentID > FromID
	Order     bool // True means acsending
	Hidden    bool // True means filter hidden torrents
	Status    Status
	Sort      SortMode
	Category  Categories
	FromDate  DateFilter
	ToDate    DateFilter
	Page      int
	UserID    uint
	Max       uint
	NotNull   string
	Language  string
	MinSize   SizeBytes
	MaxSize   SizeBytes
	Query     string
}