perfect-postcode/frontend/src/hooks/useTravelTime.ts
2026-03-14 21:36:00 +00:00

101 lines
2.7 KiB
TypeScript

import { useState, useCallback, useMemo } from 'react';
export type TransportMode = 'car' | 'bicycle' | 'walking' | 'transit';
export const TRANSPORT_MODES: TransportMode[] = ['car', 'bicycle', 'walking', 'transit'];
export const MODE_LABELS: Record<TransportMode, string> = {
car: 'Car',
bicycle: 'Bicycle',
walking: 'Walking',
transit: 'Transit',
};
export const MODE_DESCRIPTIONS: Record<TransportMode, string> = {
car: 'Drive time via the fastest road route',
bicycle: 'Cycling time using bike-friendly routes',
walking: 'Walking time along pedestrian paths and pavements',
transit: 'Journey time by train, tube, and bus',
};
export interface TravelTimeEntry {
mode: TransportMode;
slug: string;
label: string;
timeRange: [number, number] | null;
/** Use best-case (5th percentile) travel time instead of median. Transit only. */
useBest: boolean;
}
/** Field key matching the backend response: tt_{mode}_{slug} */
export function travelFieldKey(entry: TravelTimeEntry): string {
return `tt_${entry.mode}_${entry.slug}`;
}
export interface TravelTimeInitial {
entries?: TravelTimeEntry[];
}
export function useTravelTime(initial?: TravelTimeInitial) {
const [entries, setEntries] = useState<TravelTimeEntry[]>(initial?.entries ?? []);
const handleAddEntry = useCallback((mode: TransportMode) => {
setEntries((prev) => [
...prev,
{ mode, slug: '', label: '', timeRange: null, useBest: false },
]);
}, []);
const handleRemoveEntry = useCallback((index: number) => {
setEntries((prev) => prev.filter((_, i) => i !== index));
}, []);
const handleSetDestination = useCallback(
(index: number, slug: string, label: string) => {
setEntries((prev) =>
prev.map((entry, i) =>
i === index ? { ...entry, slug, label, timeRange: slug ? [0, 120] : null } : entry
)
);
},
[]
);
const handleTimeRangeChange = useCallback(
(index: number, range: [number, number]) => {
setEntries((prev) =>
prev.map((entry, i) =>
i === index ? { ...entry, timeRange: range } : entry
)
);
},
[]
);
const handleToggleBest = useCallback(
(index: number) => {
setEntries((prev) =>
prev.map((entry, i) =>
i === index ? { ...entry, useBest: !entry.useBest } : entry
)
);
},
[]
);
/** Entries that have a destination selected (slug is set) */
const activeEntries = useMemo(
() => entries.filter((e) => e.slug !== ''),
[entries]
);
return {
entries,
activeEntries,
handleAddEntry,
handleRemoveEntry,
handleSetDestination,
handleTimeRangeChange,
handleToggleBest,
};
}