Segment Interaction

1import { type Segment } from "@/lib/segments";
2 
3export interface SegmentInteraction {
4  previewSegmentId: string | null;
5  previewSegment: (segmentId: string) => void;
6  clearPreview: () => void;
7}
8 
9export interface SegmentInteractionState {
10  currentPage: number | null;
11  currentSegmentId: string | null;
12  currentSegmentIds: readonly string[];
13  previewSegmentId: string | null;
14  highlightedSegmentId: string | null;
15  highlightedSegmentIds: readonly string[];
16}
17 
18export interface SegmentViewState {
19  isPreviewed: boolean;
20  isCurrent: boolean;
21  isHighlighted: boolean;
22  isDimmed: boolean;
23}
24 
25export interface SegmentSurfaceProps {
26  state: SegmentViewState;
27  eventHandlers: {
28    onPointerEnter: () => void;
29    onPointerLeave: () => void;
30    onClick: () => void;
31  };
32  dataProps: {
33    "data-previewed": boolean;
34    "data-current": boolean;
35    "data-highlighted": boolean;
36  };
37}
38 
39export function resolvePreviewedSegmentId(
40  interaction?: Partial<Pick<SegmentInteraction, "previewSegmentId">> | null,
41): string | null {
42  return interaction?.previewSegmentId ?? null;
43}
44 
45export function getSegmentInteractionState({
46  segments,
47  currentPage,
48  interaction,
49}: {
50  segments: Segment[];
51  currentPage?: number | null;
52  interaction?: SegmentInteraction | null;
53}): SegmentInteractionState {
54  const segmentIds = new Set(segments.map((segment) => segment.id));
55  const previewSegmentId = knownSegmentId(
56    resolvePreviewedSegmentId(interaction),
57    segmentIds,
58  );
59  const resolvedCurrentPage = normalizeCurrentPage(currentPage);
60  const currentSegmentIds =
61    resolvedCurrentPage == null
62      ? []
63      : resolveCurrentSegmentIds(segments, resolvedCurrentPage);
64  const highlightedSegmentIds =
65    previewSegmentId != null ? [previewSegmentId] : currentSegmentIds;
66 
67  return {
68    currentPage: resolvedCurrentPage,
69    currentSegmentId: currentSegmentIds[0] ?? null,
70    currentSegmentIds,
71    previewSegmentId,
72    highlightedSegmentId: highlightedSegmentIds[0] ?? null,
73    highlightedSegmentIds,
74  };
75}
76 
77export function scopeSegmentInteraction(
78  interaction: SegmentInteraction | null | undefined,
79  segmentIds: Iterable<string>,
80): SegmentInteraction | null | undefined {
81  if (!interaction) return interaction;
82 
83  const knownIds = new Set(segmentIds);
84  const previewSegmentId = knownSegmentId(
85    interaction.previewSegmentId,
86    knownIds,
87  );
88 
89  if (previewSegmentId === interaction.previewSegmentId) {
90    return interaction;
91  }
92 
93  return {
94    ...interaction,
95// … truncated