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/**
* Copyright (c) JOB TODAY S.A. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
*/
import {
Animated,
GestureResponderEvent,
PanResponder,
PanResponderGestureState,
PanResponderInstance,
NativeTouchEvent,
} from 'react-native'
import {Dimensions, Position} from './@types'
type CacheStorageItem = {key: string; value: any}
export const createCache = (cacheSize: number) => ({
_storage: [] as CacheStorageItem[],
get(key: string): any {
const {value} =
this._storage.find(({key: storageKey}) => storageKey === key) || {}
return value
},
set(key: string, value: any) {
if (this._storage.length >= cacheSize) {
this._storage.shift()
}
this._storage.push({key, value})
},
})
export const splitArrayIntoBatches = (arr: any[], batchSize: number): any[] =>
arr.reduce((result, item) => {
const batch = result.pop() || []
if (batch.length < batchSize) {
batch.push(item)
result.push(batch)
} else {
result.push(batch, [item])
}
return result
}, [])
export const getImageTransform = (
image: Dimensions | null,
screen: Dimensions,
) => {
if (!image?.width || !image?.height) {
return [] as const
}
const wScale = screen.width / image.width
const hScale = screen.height / image.height
const scale = Math.min(wScale, hScale)
const {x, y} = getImageTranslate(image, screen)
return [{x, y}, scale] as const
}
export const getImageStyles = (
image: Dimensions | null,
translate: Animated.ValueXY,
scale?: Animated.Value,
) => {
if (!image?.width || !image?.height) {
return {width: 0, height: 0}
}
const transform = translate.getTranslateTransform()
if (scale) {
// @ts-ignore TODO - is scale incorrect? might need to remove -prf
transform.push({scale}, {perspective: new Animated.Value(1000)})
}
return {
width: image.width,
height: image.height,
transform,
}
}
export const getImageTranslate = (
image: Dimensions,
screen: Dimensions,
): Position => {
const getTranslateForAxis = (axis: 'x' | 'y'): number => {
const imageSize = axis === 'x' ? image.width : image.height
const screenSize = axis === 'x' ? screen.width : screen.height
return (screenSize - imageSize) / 2
}
return {
x: getTranslateForAxis('x'),
y: getTranslateForAxis('y'),
}
}
export const getImageDimensionsByTranslate = (
translate: Position,
screen: Dimensions,
): Dimensions => ({
width: screen.width - translate.x * 2,
height: screen.height - translate.y * 2,
})
export const getImageTranslateForScale = (
currentTranslate: Position,
targetScale: number,
screen: Dimensions,
): Position => {
const {width, height} = getImageDimensionsByTranslate(
currentTranslate,
screen,
)
const targetImageDimensions = {
width: width * targetScale,
height: height * targetScale,
}
return getImageTranslate(targetImageDimensions, screen)
}
type HandlerType = (
event: GestureResponderEvent,
state: PanResponderGestureState,
) => void
type PanResponderProps = {
onGrant: HandlerType
onStart?: HandlerType
onMove: HandlerType
onRelease?: HandlerType
onTerminate?: HandlerType
}
export const createPanResponder = ({
onGrant,
onStart,
onMove,
onRelease,
onTerminate,
}: PanResponderProps): PanResponderInstance =>
PanResponder.create({
onStartShouldSetPanResponder: () => true,
onStartShouldSetPanResponderCapture: () => true,
onMoveShouldSetPanResponder: () => true,
onMoveShouldSetPanResponderCapture: () => true,
onPanResponderGrant: onGrant,
onPanResponderStart: onStart,
onPanResponderMove: onMove,
onPanResponderRelease: onRelease,
onPanResponderTerminate: onTerminate,
onPanResponderTerminationRequest: () => false,
onShouldBlockNativeResponder: () => false,
})
export const getDistanceBetweenTouches = (
touches: NativeTouchEvent[],
): number => {
const [a, b] = touches
if (a == null || b == null) {
return 0
}
return Math.sqrt(
Math.pow(a.pageX - b.pageX, 2) + Math.pow(a.pageY - b.pageY, 2),
)
}
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