tracker

3.5 KB

1. // lib/follows.hl — per-user follow data (tracker.worldapi.org#5): which shows a user follows; since mission 047 also the
2. // show page's Follow toggle (`setFollowed`).
3. // storage/mpackdb/follows.db, migrated by tools/migrate.hl (tracker.worldapi.org#2): { show, user, at, oldId }.
4. // Kept apart from shows.hl (show data) and watches.hl (watch state) so /unwatched, /schedule and /my/shows (tickets #5/#6/#7,
5. // "reuse, don't copy") can all import the same functions.
6. import { MPackDB } from 'hl:mpackdb'
7. import { now } from 'hl:time'
8. import { randomBytes } from 'hl:crypto'
9. import { storageDir } from './util.hl'
11. static followsTable = new MPackDB(file = storageDir + '/follows.db', primaryKey = '@id', indexes = ['!oldId'])
13. // every follow record of this user ({ show, user, at, … }, `at` = epoch ms) — a linear scan (128 rows
14. // total across every user, migrated data; cheap once per page load) — no declared index on `user`.
15. // /my/shows (tracker.worldapi.org#7) needs the whole record for its follow-date order.
16. static followsOfUser = (&userId) => {
17. if (userId == null) { return [] }
18. out = []
19. for (f of followsTable.find(null, null)) { if (f.user == userId && f.show != null) { out.push(f) } }
20. return out
21. }
23. // insertion sort, hand-written (no list sort(), hybriel#1) — newest follow first; `at` is epoch ms (migrated
24. // `_createdAt`, or now() for a new follow), a missing one counts as the oldest. Rows carry `followedAt`.
25. // /my/shows and /my/movies (tracker.worldapi.org#7/#13)
26. static insertByFollowDesc = (&sorted, &row) => {
27. out = []
28. let inserted = false
29. for (x of sorted) {
30. if (!inserted && row.followedAt >= x.followedAt) { out.push(row) inserted = true }
31. out.push(x)
32. }
33. if (!inserted) { out.push(row) }
34. return out
35. }
37. // the ids of every show this user follows
38. static followedShowIds = (&userId) => {
39. out = []
40. for (f of followsOfUser(userId)) { out.push(f.show) }
41. return out
42. }
44. // every show ANYONE follows, each once, in follow-table order — what the TMDB sync (sync.hl,
45. // tracker.worldapi.org#9) keeps up to date
46. static allFollowedShowIds = () => {
47. seen = {}
48. out = []
49. for (f of followsTable.find(null, null)) {
50. if (f.show != null && seen[f.show] != true) { seen[f.show] = true out.push(f.show) }
51. }
52. return out
53. }
55. // mission 047 (the show page's Follow / Following toggle): does this user follow this show?
56. static isFollowing = (&userId, &showId) => {
57. if (userId == null || showId == null) { return false }
58. for (f of followsOfUser(userId)) { if (f.show == showId) { return true } }
59. return false
60. }
62. // follow (a new record, follow date = now → the top of /my/shows) or unfollow (every record of this user+show is
63. // deleted). Own 16-hex id + a unique `oldId` marker (the `!oldId` UNIQUE index refuses a second null), never update()
64. // (hybriel#113) — the same shape as watches.hl `setWatched`.
65. static setFollowed = (&userId, &showId, &follow) => {
66. if (userId == null || showId == null) { return false }
67. mine = []
68. for (f of followsOfUser(userId)) { if (f.show == showId) { mine.push(f) } }
69. if (follow) {
70. if (mine.length > 0) { return true }
71. id = followsTable.put({ id = randomBytes(8, 'hex') show = showId user = userId at = now() oldId = 'app:' + randomBytes(8, 'hex') })
72. return id != null
73. }
74. let ok = true
75. for (f of mine) { ok = followsTable.delete(f.id) > 0 && ok }
76. return ok
77. }
79. // the show page's Follow button (components/show.hl face showToggleFollow): following → not, not → following; the new state, or
80. // null when it could not be saved
81. static toggleFollowed = (&userId, &showId) => {
82. follow = isFollowing(userId, showId) == false
83. return setFollowed(userId, showId, follow) ? follow : null
84. }