Move logic to fns

src/utils/page.js

@@ -1,9 +1,15 @@
-export function getNextPageIndexLimited(currentPageIndex, pagesCount) {
+export function getNextPageIndexLimited({
+  currentPageIndex,
+  pagesCount,
+}) {
   if (pagesCount < 1) throw new Error('pagesCount must be at least 1')
   return Math.min(Math.max(currentPageIndex + 1, 0), pagesCount - 1)
 }
 
-export function getNextPageIndexInfinte(currentPageIndex, pagesCount) {
+export function getNextPageIndexInfinte({
+  currentPageIndex,
+  pagesCount,
+}) {
   if (pagesCount < 1) throw new Error('pagesCount must be at least 1')
   const newCurrentPageIndex = Math.max(currentPageIndex, 0) + 1
   return newCurrentPageIndex > pagesCount - 1 ? 0 : Math.max(newCurrentPageIndex, 0)
@@ -13,12 +19,18 @@ export function getNextPageIndexFn(infinite) {
   return infinite ? getNextPageIndexInfinte : getNextPageIndexLimited
 }
 
-export function getPrevPageIndexLimited(currentPageIndex, pagesCount) {
+export function getPrevPageIndexLimited({
+  currentPageIndex,
+  pagesCount,
+}) {
   if (pagesCount < 1) throw new Error('pagesCount must be at least 1')
   return Math.max(Math.min(currentPageIndex - 1, pagesCount - 1), 0)
 }
 
-export function getPrevPageIndexInfinte(currentPageIndex, pagesCount) {
+export function getPrevPageIndexInfinte({
+  currentPageIndex,
+  pagesCount,
+}) {
   if (pagesCount < 1) throw new Error('pagesCount must be at least 1')
   const newCurrentPageIndex = Math.min(currentPageIndex, pagesCount - 1) - 1
   return newCurrentPageIndex >= 0 ? Math.min(newCurrentPageIndex, pagesCount - 1) : pagesCount - 1
@@ -28,12 +40,19 @@ export function getPrevPageIndexFn(infinite) {
   return infinite ? getPrevPageIndexInfinte : getPrevPageIndexLimited
 }
 
-export function getPageIndex(pageIndex, pagesCount) {
+export function getPageIndex({
+  pageIndex,
+  pagesCount,
+}) {
   if (pagesCount < 1) throw new Error('pagesCount must be at least 1')
   return pageIndex < 0 ? 0 : Math.min(pageIndex, pagesCount - 1)
 }
 
-export function getAdjacentIndexes(pageIndex, pagesCount, infinite) {
+export function getAdjacentIndexes({
+  pageIndex,
+  pagesCount,
+  infinite,
+}) {
   if (pagesCount < 1) throw new Error('pagesCount must be at least 1')
   const _pageIndex = Math.max(0, Math.min(pageIndex, pagesCount - 1))
   let rangeStart = _pageIndex - 1;
@@ -50,3 +69,91 @@ export function getAdjacentIndexes(pageIndex, pagesCount, infinite) {
     : rangeEnd
   return [...new Set([rangeStart, rangeEnd, _pageIndex])].sort((a, b) => a - b)
 }
+
+export function getClones({
+  oneSideClonesCount,
+  pagesContainerChildren,
+}) {
+  // TODO: add fns to remove clones if needed
+  const clonesToAppend = []
+  for (let i=0; i<oneSideClonesCount; i++) {
+    clonesToAppend.push(pagesContainerChildren[i].cloneNode(true))
+  }
+
+  const clonesToPrepend = []
+  const len = pagesContainerChildren.length
+  for (let i=len-1; i>len-1-oneSideClonesCount; i--) {
+    clonesToPrepend.push(pagesContainerChildren[i].cloneNode(true))
+  }
+
+  return {
+    clonesToAppend,
+    clonesToPrepend,
+  }
+}
+
+export function applyClones({
+  pagesContainer,
+  clonesToAppend,
+  clonesToPrepend,
+}) {
+  for (let i=0; i<clonesToAppend.length; i++) {
+    pagesContainer.append(clonesToAppend[i])
+  }
+  for (let i=0; i<clonesToPrepend.length; i++) {
+    pagesContainer.prepend(clonesToPrepend[i])
+  }
+}
+
+export function getPageSizes({
+  pageWindowElement,
+  pagesContainerChildren,
+}) {
+  const pagesWindowWidth = pageWindowElement.clientWidth
+  const pageWidth = pagesWindowWidth
+  const pagesCount = pagesContainerChildren.length
+
+  return {
+    pagesWindowWidth,
+    pageWidth,
+    pagesCount,
+  }
+}
+
+export function applyPageSizes({
+  pagesContainerChildren,
+  pageWidth,
+}) {
+  for (let pageIndex=0; pageIndex<pagesContainerChildren.length; pageIndex++) {
+    pagesContainerChildren[pageIndex].style.minWidth = `${pageWidth}px`
+    pagesContainerChildren[pageIndex].style.maxWidth = `${pageWidth}px`
+  }
+}
+
+export function getCurrentPageIndexWithoutClones({
+  currentPageIndex,
+  pagesCount,
+  oneSideClonesCount,
+  infinite,
+}) {
+  if (infinite) {
+    if (currentPageIndex === pagesCount - 1) return 0
+    if (currentPageIndex === 0) return (pagesCount - oneSideClonesCount * 2) - 1
+    return currentPageIndex - 1
+  }
+  return currentPageIndex
+}
+
+export function getPagesCountWithoutClones({
+  pagesCount,
+  oneSideClonesCount,
+}) {
+  const bothSidesClonesCount = oneSideClonesCount * 2
+  return Math.max(pagesCount - bothSidesClonesCount, 1)
+}
+
+export function getOneSideClonesCount({
+  infinite,
+}) {
+  return infinite ? 1 : 0
+}