fishroll.gno

 1package fishroll
 2
 3import (
 4	"crypto/sha256"
 5	"strconv"
 6)
 7
 8var (
 9	hpBase   = [6]int{100, 122, 148, 178, 214, 256}
10	biteBase = [6]int{24, 30, 37, 45, 54, 66}
11	spdBase  = [6]int{108, 104, 100, 96, 92, 88}
12	rarities = [6]string{"common", "uncommon", "rare", "epic", "legendary", "mythic"}
13	traits   = [3]string{"swift", "fang", "hide"}
14)
15
16func Version() string { return "roll-1" }
17
18func Roll(caller address, commitH int64, entropyH int64, id int) (rarity string, trait string, bite int, hp int, speed int) {
19	if id < 1 || commitH < 1 || entropyH != commitH+2 {
20		panic("roll")
21	}
22	raw := caller.String() + "|" + strconv.FormatInt(commitH, 10) + "|" + strconv.FormatInt(entropyH, 10) + "|" + strconv.Itoa(id)
23	sum := sha256.Sum256([]byte(raw))
24	n := (int(sum[0])<<8 | int(sum[1])) % 10000
25	tier := 0
26	if n == 0 {
27		tier = 5
28	} else if n < 4 {
29		tier = 4
30	} else if n < 14 {
31		tier = 3
32	} else if n < 54 {
33		tier = 2
34	} else if n < 254 {
35		tier = 1
36	}
37	kind := int(sum[2]) % 3
38	bite = biteBase[tier]
39	hp = hpBase[tier]
40	speed = spdBase[tier]
41	if kind == 0 {
42		speed = (speed*112 + 50) / 100
43	} else if kind == 1 {
44		bite = (bite*112 + 50) / 100
45	} else {
46		hp = (hp*112 + 50) / 100
47	}
48	return rarities[tier], traits[kind], bite, hp, speed
49}