streaks.gno

  1// Package streaks is an on-chain habit-streak tracker. Call CheckIn() again
  2// within graceBlocks of your last check-in and the streak keeps growing; let
  3// the gap run past that and it resets to zero on your next check-in. Gno has
  4// no wall clock, so "again soon enough" is measured in blocks rather than
  5// calendar days — graceBlocks is the tunable stand-in for "before tomorrow".
  6package streaks
  7
  8import (
  9	"sort"
 10	"strconv"
 11
 12	"chain/runtime"
 13
 14	"gno.land/p/nt/avl/v0"
 15)
 16
 17// graceBlocks is the max block gap between two check-ins that still counts
 18// as consecutive. A gap larger than this lapses the streak.
 19const graceBlocks int64 = 100
 20
 21// record is the persisted streak state for one address.
 22type record struct {
 23	owner      address
 24	current    int64
 25	longest    int64
 26	total      int64
 27	lastHeight int64
 28}
 29
 30var streaks avl.Tree // owner address string -> *record
 31
 32func get(owner address) (*record, bool) {
 33	v, ok := streaks.Get(owner.String()).(*record)
 34	return v, ok
 35}
 36
 37// project reports the record's current streak as of height without
 38// mutating it: once the gap since lastHeight exceeds graceBlocks the streak
 39// reads as lapsed, even though the stored value only resets on the next
 40// actual check-in.
 41func project(r *record, height int64) (current int64, alive bool) {
 42	if height-r.lastHeight > graceBlocks {
 43		return 0, false
 44	}
 45	return r.current, true
 46}
 47
 48// checkin is the non-crossing core of CheckIn, kept separate so unit tests
 49// can drive it directly by address and height.
 50func checkin(owner address, height int64) string {
 51	r, ok := get(owner)
 52	if !ok {
 53		r = &record{owner: owner}
 54		streaks.Set(owner.String(), r)
 55	} else {
 56		if height <= r.lastHeight {
 57			panic("already checked in at this block height")
 58		}
 59		if height-r.lastHeight > graceBlocks {
 60			r.current = 0
 61		}
 62	}
 63	r.current++
 64	if r.current > r.longest {
 65		r.longest = r.current
 66	}
 67	r.lastHeight = height
 68	r.total++
 69	return "checked in — current streak: " + strconv.FormatInt(r.current, 10) + " 🔥"
 70}
 71
 72// CheckIn records a check-in for the caller at the current block height.
 73func CheckIn(cur realm) string {
 74	if !cur.IsCurrent() {
 75		panic("spoofed realm")
 76	}
 77	return checkin(cur.Previous().Address(), runtime.ChainHeight())
 78}
 79
 80// CurrentStreak returns addr's live current streak, 0 if it has lapsed or
 81// addr has never checked in.
 82func CurrentStreak(addr string) int64 {
 83	r, ok := get(address(addr))
 84	if !ok {
 85		return 0
 86	}
 87	current, _ := project(r, runtime.ChainHeight())
 88	return current
 89}
 90
 91// LongestStreak returns addr's best streak ever, 0 if it has never checked in.
 92func LongestStreak(addr string) int64 {
 93	r, ok := get(address(addr))
 94	if !ok {
 95		return 0
 96	}
 97	return r.longest
 98}
 99
100// byRank orders the leaderboard by longest streak, then current streak, then
101// owner address — fully deterministic regardless of avl iteration order.
102type byRank []*record
103
104func (b byRank) Len() int      { return len(b) }
105func (b byRank) Swap(i, j int) { b[i], b[j] = b[j], b[i] }
106func (b byRank) Less(i, j int) bool {
107	if b[i].longest != b[j].longest {
108		return b[i].longest > b[j].longest
109	}
110	if b[i].current != b[j].current {
111		return b[i].current > b[j].current
112	}
113	return b[i].owner.String() < b[j].owner.String()
114}
115
116func shortAddr(a address) string {
117	s := a.String()
118	if len(s) > 12 {
119		return s[:8] + "…" + s[len(s)-4:]
120	}
121	return s
122}
123
124func renderDetail(r *record, height int64) string {
125	current, alive := project(r, height)
126	status := "🔥 active"
127	if !alive {
128		status = "💤 lapsed"
129	}
130	out := "## `" + shortAddr(r.owner) + "`\n\n"
131	out += "- Status: " + status + "\n"
132	out += "- Current streak: " + strconv.FormatInt(current, 10) + "\n"
133	out += "- Longest streak: " + strconv.FormatInt(r.longest, 10) + "\n"
134	out += "- Total check-ins: " + strconv.FormatInt(r.total, 10) + "\n"
135	out += "- Last check-in at block " + strconv.FormatInt(r.lastHeight, 10) + "\n"
136	return out
137}
138
139// Render shows either the full leaderboard (path == "") or a single
140// address's detail card when path is a bech32 address.
141func Render(path string) string {
142	height := runtime.ChainHeight()
143
144	out := "# 🔥 Streaks\n\n"
145	out += "An on-chain habit-streak tracker. Call `CheckIn()` again within " +
146		strconv.FormatInt(graceBlocks, 10) + " blocks of your last check-in to keep it alive; " +
147		"wait longer than that and it resets to zero on your next check-in.\n\n"
148
149	if path != "" {
150		r, ok := get(address(path))
151		if !ok {
152			return out + "_No check-ins yet for `" + path + "`._\n"
153		}
154		return out + renderDetail(r, height)
155	}
156
157	var rows []*record
158	streaks.Iterate("", "", func(_ string, v any) bool {
159		rows = append(rows, v.(*record))
160		return false
161	})
162	if len(rows) == 0 {
163		out += "_Nobody has checked in yet. Be the first!_\n"
164		return out
165	}
166	sort.Stable(byRank(rows))
167
168	out += "| Rank | Address | Status | Current | Longest | Total |\n"
169	out += "| ---: | :--- | :--- | ---: | ---: | ---: |\n"
170	for i, r := range rows {
171		current, alive := project(r, height)
172		status := "🔥"
173		if !alive {
174			status = "💤"
175		}
176		out += "| " + strconv.Itoa(i+1) + " | `" + shortAddr(r.owner) + "` | " + status +
177			" | " + strconv.FormatInt(current, 10) + " | " + strconv.FormatInt(r.longest, 10) +
178			" | " + strconv.FormatInt(r.total, 10) + " |\n"
179	}
180	out += "\n_View a single address at `?<address>`._\n"
181	return out
182}