openmedialibrary/static/reader/pdf.js
2019-01-22 19:36:48 +05:30

125 lines
4 KiB
JavaScript

var id = document.location.pathname.split('/')[1];
var annotations = JSON.parse(localStorage[id + '.annotations'] || '[]')
var currentPage = 1, rendered = false
function getID() {
var id = 0;
while (annotations.filter(function(a) {
return a.id == id
}).length) {
id++
}
return id
}
window.addEventListener('keydown', function(event) {
if (event.key == 'Delete') {
var selected = document.querySelector('.oml-annotation.selected')
if (selected) {
removeAnnotation(selected.dataset.id)
}
} else if (event.key == 'n') {
if (!window.getSelection().isCollapsed) {
var annot = getHighlight()
renderAnnotation(annot)
addAnnotation(annot)
window.getSelection().removeAllRanges();
}
event.stopPropagation()
event.preventDefault()
}
})
window.addEventListener('pagerendered', function (event) {
loadAnnotations(event.detail.pageNumber - 1)
})
function getHighlight() {
var pageIndex = PDFViewerApplication.pdfViewer.currentPageNumber - 1;
var page = PDFViewerApplication.pdfViewer.getPageView(pageIndex);
var pageRect = page.canvas.getClientRects()[0];
var selectionRects = window.getSelection().getRangeAt(0).getClientRects();
var viewport = page.viewport;
var selected = Array.from(selectionRects).map(function (r) {
return viewport.convertToPdfPoint(r.left - pageRect.x, r.top - pageRect.y).concat(
viewport.convertToPdfPoint(r.right - pageRect.x, r.bottom - pageRect.y));
});
return {page: pageIndex, coords: selected, id: getID()};
}
function renderAnnotation(annotation) {
var pageIndex = annotation.page;
var page = PDFViewerApplication.pdfViewer.getPageView(pageIndex);
if (!page.canvas) {
setTimeout(function() {
renderAnnotation(annotation)
}, 10)
return
}
var pageElement = page.canvas.parentElement.parentElement;
var viewport = page.viewport;
annotation.coords.forEach(function (rect) {
var bounds = viewport.convertToViewportRectangle(rect);
var el = document.createElement('div');
el.classList.add('oml-annotation')
el.classList.add('a' + annotation.id)
el.classList.add('page' + annotation.page)
el.dataset.id = annotation.id
el.setAttribute('style', 'position: absolute; background-color: yellow;opacity:0.3;' +
'left:' + Math.min(bounds[0], bounds[2]) + 'px; top:' + Math.min(bounds[1], bounds[3]) + 'px;' +
'width:' + Math.abs(bounds[0] - bounds[2]) + 'px; height:' + Math.abs(bounds[1] - bounds[3]) + 'px;');
el.addEventListener('click', function() {
if (el.classList.contains('selected')) {
deselectAnnotation(annotation.id)
} else {
selectAnnotation(annotation.id)
}
});
pageElement.appendChild(el);
});
}
function addAnnotation(annotation) {
annotations.push(annotation)
saveAnnotations()
}
function selectAnnotation(id) {
document.querySelectorAll('.oml-annotation.a' + id).forEach(function(g) {
g.classList.add('selected')
g.style.backgroundColor = 'blue'
})
}
function deselectAnnotation(id) {
document.querySelectorAll('.oml-annotation.a' + id).forEach(function(g) {
g.classList.remove('selected')
g.style.backgroundColor = 'yellow'
})
}
function removeAnnotation(id) {
document.querySelectorAll('.oml-annotation.a' + id).forEach(function(a) {
a.remove()
})
annotations = annotations.filter(function(annotation) {
return annotation.id != id
})
saveAnnotations()
}
function saveAnnotations() {
localStorage[id + '.annotations'] = JSON.stringify(annotations)
}
function loadAnnotations(page) {
document.querySelectorAll('.oml-annotation.page' + page).forEach(function(e) {
e.remove()
})
annotations.filter(function(a) {
return a.page == page
}).forEach(function(annot) {
renderAnnotation(annot)
})
}