perfect-postcode/frontend/src/hooks/useTravelTime.ts
2026-05-15 08:17:05 +01:00

134 lines
4 KiB
TypeScript

import { useState, useCallback, useMemo } from 'react';
import type { ComponentType } from 'react';
import { useTranslation } from 'react-i18next';
import { CarIcon, BicycleIcon, WalkingIcon, TransitIcon } from '../components/ui/icons';
import { dedupeTravelTimeEntries } from '../lib/travel-params';
export type TransportMode = 'car' | 'bicycle' | 'walking' | 'transit';
export const TRANSPORT_MODES: TransportMode[] = ['transit', 'car', 'bicycle', 'walking'];
export const MODE_LABELS: Record<TransportMode, string> = {
car: 'Car',
bicycle: 'Bicycle',
walking: 'Walking',
transit: 'Public Transport',
};
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 const MODE_ICONS: Record<TransportMode, ComponentType<{ className?: string }>> = {
car: CarIcon,
bicycle: BicycleIcon,
walking: WalkingIcon,
transit: TransitIcon,
};
/**
* Hook returning translated mode labels and descriptions.
*/
export function useTranslatedModes() {
const { t } = useTranslation();
const label = useCallback(
(mode: TransportMode): string =>
({
car: t('travel.modeCar'),
bicycle: t('travel.modeBicycle'),
walking: t('travel.modeWalking'),
transit: t('travel.modeTransit'),
})[mode],
[t]
);
const desc = useCallback(
(mode: TransportMode): string =>
({
car: t('travel.modeCarDesc'),
bicycle: t('travel.modeBicycleDesc'),
walking: t('travel.modeWalkingDesc'),
transit: t('travel.modeTransitDesc'),
})[mode],
[t]
);
return { label, desc };
}
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[]>(() =>
dedupeTravelTimeEntries(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) =>
dedupeTravelTimeEntries(
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) =>
dedupeTravelTimeEntries(
prev.map((entry, i) => (i === index ? { ...entry, timeRange: range } : entry))
)
);
}, []);
const handleToggleBest = useCallback((index: number) => {
setEntries((prev) =>
dedupeTravelTimeEntries(
prev.map((entry, i) => (i === index ? { ...entry, useBest: !entry.useBest } : entry))
)
);
}, []);
const handleSetEntries = useCallback((newEntries: TravelTimeEntry[]) => {
setEntries(dedupeTravelTimeEntries(newEntries));
}, []);
/** Entries that have a destination selected (slug is set) */
const activeEntries = useMemo(() => entries.filter((e) => e.slug !== ''), [entries]);
return {
entries,
activeEntries,
handleAddEntry,
handleRemoveEntry,
handleSetDestination,
handleSetEntries,
handleTimeRangeChange,
handleToggleBest,
};
}