react-pdf
Version:
Display PDFs in your React app as easily as if they were images.
169 lines (168 loc) • 6.29 kB
JavaScript
'use client';
import { jsx as _jsx } from "react/jsx-runtime";
import { useCallback, useEffect, useLayoutEffect, useMemo, useRef } from 'react';
import makeCancellable from 'make-cancellable-promise';
import clsx from 'clsx';
import invariant from 'tiny-invariant';
import warning from 'warning';
import * as pdfjs from 'pdfjs-dist';
import usePageContext from '../shared/hooks/usePageContext.js';
import useResolver from '../shared/hooks/useResolver.js';
import { cancelRunningTask } from '../shared/utils.js';
function isTextItem(item) {
return 'str' in item;
}
export default function TextLayer() {
const pageContext = usePageContext();
invariant(pageContext, 'Unable to find Page context.');
const { customTextRenderer, onGetTextError, onGetTextSuccess, onRenderTextLayerError, onRenderTextLayerSuccess, page, pageIndex, pageNumber, rotate, scale, } = pageContext;
invariant(page, 'Attempted to load page text content, but no page was specified.');
const [textContentState, textContentDispatch] = useResolver();
const { value: textContent, error: textContentError } = textContentState;
const layerElement = useRef(null);
warning(Number.parseInt(window.getComputedStyle(document.body).getPropertyValue('--react-pdf-text-layer'), 10) === 1, 'TextLayer styles not found. Read more: https://github.com/wojtekmaj/react-pdf#support-for-text-layer');
/**
* Called when a page text content is read successfully
*/
function onLoadSuccess() {
if (!textContent) {
// Impossible, but TypeScript doesn't know that
return;
}
if (onGetTextSuccess) {
onGetTextSuccess(textContent);
}
}
/**
* Called when a page text content failed to read successfully
*/
function onLoadError() {
if (!textContentError) {
// Impossible, but TypeScript doesn't know that
return;
}
warning(false, textContentError.toString());
if (onGetTextError) {
onGetTextError(textContentError);
}
}
// biome-ignore lint/correctness/useExhaustiveDependencies: useEffect intentionally triggered on page change
useEffect(function resetTextContent() {
textContentDispatch({ type: 'RESET' });
}, [page, textContentDispatch]);
useEffect(function loadTextContent() {
if (!page) {
return;
}
const cancellable = makeCancellable(page.getTextContent());
const runningTask = cancellable;
cancellable.promise
.then((nextTextContent) => {
textContentDispatch({ type: 'RESOLVE', value: nextTextContent });
})
.catch((error) => {
textContentDispatch({ type: 'REJECT', error });
});
return () => cancelRunningTask(runningTask);
}, [page, textContentDispatch]);
// biome-ignore lint/correctness/useExhaustiveDependencies: Ommitted callbacks so they are not called every time they change
useEffect(() => {
if (textContent === undefined) {
return;
}
if (textContent === false) {
onLoadError();
return;
}
onLoadSuccess();
}, [textContent]);
/**
* Called when a text layer is rendered successfully
*/
const onRenderSuccess = useCallback(() => {
if (onRenderTextLayerSuccess) {
onRenderTextLayerSuccess();
}
}, [onRenderTextLayerSuccess]);
/**
* Called when a text layer failed to render successfully
*/
const onRenderError = useCallback((error) => {
warning(false, error.toString());
if (onRenderTextLayerError) {
onRenderTextLayerError(error);
}
}, [onRenderTextLayerError]);
function onMouseDown() {
const layer = layerElement.current;
if (!layer) {
return;
}
layer.classList.add('selecting');
}
function onMouseUp() {
const layer = layerElement.current;
if (!layer) {
return;
}
layer.classList.remove('selecting');
}
const viewport = useMemo(() => page.getViewport({ scale, rotation: rotate }), [page, rotate, scale]);
useLayoutEffect(function renderTextLayer() {
if (!page || !textContent) {
return;
}
const { current: layer } = layerElement;
if (!layer) {
return;
}
layer.innerHTML = '';
const textContentSource = page.streamTextContent({ includeMarkedContent: true });
const parameters = {
container: layer,
textContentSource,
viewport,
};
const cancellable = new pdfjs.TextLayer(parameters);
const runningTask = cancellable;
cancellable
.render()
.then(() => {
const end = document.createElement('div');
end.className = 'endOfContent';
layer.append(end);
const layerChildren = layer.querySelectorAll('[role="presentation"]');
if (customTextRenderer) {
let index = 0;
textContent.items.forEach((item, itemIndex) => {
if (!isTextItem(item)) {
return;
}
const child = layerChildren[index];
if (!child) {
return;
}
const content = customTextRenderer(Object.assign({ pageIndex,
pageNumber,
itemIndex }, item));
child.innerHTML = content;
index += item.str && item.hasEOL ? 2 : 1;
});
}
// Intentional immediate callback
onRenderSuccess();
})
.catch(onRenderError);
return () => cancelRunningTask(runningTask);
}, [
customTextRenderer,
onRenderError,
onRenderSuccess,
page,
pageIndex,
pageNumber,
textContent,
viewport,
]);
return (_jsx("div", { className: clsx('react-pdf__Page__textContent', 'textLayer'), onMouseUp: onMouseUp, onMouseDown: onMouseDown, ref: layerElement }));
}