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pagedjs-repeat-table-header
class RepeatTableHeadersHandler extends Paged.Handler {
constructor(chunker, polisher, caller) {
super(chunker, polisher, caller)
this.splitTablesRefs = []
}
afterPageLayout(pageElement, page, breakToken, chunker) {
this.chunker = chunker
this.splitTablesRefs = []
if (breakToken) {
const node = breakToken.node
const tables = this.findAllAncestors(node, "table")
if (node.tagName === "TABLE") tables.push(node)
if (tables.length > 0) {
this.splitTablesRefs = tables.map(t => t.dataset.ref)
let thead = node.tagName === "THEAD" ? node : this.findFirstAncestor(node, "thead")
if (thead) {
let lastTheadNode = thead.hasChildNodes() ? thead.lastChild : thead
breakToken.node = this.nodeAfter(lastTheadNode, chunker.source)
}
this.hideEmptyTables(pageElement, node)
}
}
}
hideEmptyTables(pageElement, breakTokenNode) {
this.splitTablesRefs.forEach(ref => {
let table = pageElement.querySelector("[data-ref='" + ref + "']")
if (table) {
let sourceBody = table.querySelector("tbody > tr")
if (!sourceBody || this.refEquals(sourceBody.firstElementChild, breakTokenNode)) {
table.style.visibility = "hidden"
table.style.position = "absolute"
let lineSpacer = table.nextSibling
if (lineSpacer) {
lineSpacer.style.visibility = "hidden"
lineSpacer.style.position = "absolute"
}
}
}
})
}
refEquals(a, b) {
return a && a.dataset && b && b.dataset && a.dataset.ref === b.dataset.ref
}
findFirstAncestor(element, selector) {
while (element.parentNode && element.parentNode.nodeType === 1) {
if (element.parentNode.matches(selector)) return element.parentNode
element = element.parentNode
}
return null
}
findAllAncestors(element, selector) {
const ancestors = []
while (element.parentNode && element.parentNode.nodeType === 1) {
if (element.parentNode.matches(selector)) ancestors.unshift(element.parentNode)
element = element.parentNode
}
return ancestors
}
layout(rendered, layout) {
this.splitTablesRefs.forEach(ref => {
const renderedTable = rendered.querySelector("[data-ref='" + ref + "']")
if (renderedTable) {
if (!renderedTable.getAttribute("repeated-headers")) {
const sourceTable = this.chunker.source.querySelector("[data-ref='" + ref + "']")
this.repeatColgroup(sourceTable, renderedTable)
this.repeatTHead(sourceTable, renderedTable)
renderedTable.setAttribute("repeated-headers", true)
}
}
})
}
repeatColgroup(sourceTable, renderedTable) {
let colgroup = sourceTable.querySelectorAll("colgroup")
let firstChild = renderedTable.firstChild
colgroup.forEach((colgroup) => {
let clonedColgroup = colgroup.cloneNode(true)
renderedTable.insertBefore(clonedColgroup, firstChild)
})
}
repeatTHead(sourceTable, renderedTable) {
let thead = sourceTable.querySelector("thead")
if (thead) {
let clonedThead = thead.cloneNode(true)
renderedTable.insertBefore(clonedThead, renderedTable.firstChild)
}
}
nodeAfter(node, limiter) {
if (limiter && node === limiter) return
let significantNode = this.nextSignificantNode(node)
if (significantNode) return significantNode
if (node.parentNode) {
while ((node = node.parentNode)) {
if (limiter && node === limiter) return
significantNode = this.nextSignificantNode(node)
if (significantNode) return significantNode
}
}
}
nextSignificantNode(sib) {
while ((sib = sib.nextSibling)) { if (!this.isIgnorable(sib)) return sib }
return null
}
isIgnorable(node) {
return (
(node.nodeType === 8)
|| ((node.nodeType === 3) && this.isAllWhitespace(node))
)
}
isAllWhitespace(node) {
return !(/[^\t\n\r ]/.test(node.textContent))
}
}
Paged.registerHandlers(RepeatTableHeadersHandler)
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