Bhargava 6063bd1724 Help Project:
1. Initial Commit - a boiler plate code and POC to realize the concept of context
sensitive help
2. Frontend code written in ReactJS
3. Backend code written in Java, Spring Boot Framework
4. Frontend Start:
        pre-requisites : node, npm
	npm run dev  ==> to start the frontend vite server
5. Backend Start:
	pre-requisites : java, mvn
        mvn spring-boot:run  ==> to start the backend server
6. Visit http://localhost:5173/ for basic demo of help, press F1 in textboxes
7. Visit http://localhost:5173/editor and enter "admin123" to add/modify texts.

Happy Coding !!!

Thank you,
Bhargava.
2025-07-04 15:54:13 +05:30

201 lines
7.3 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.Preprocessor = void 0;
const unicode_js_1 = require("../common/unicode.js");
const error_codes_js_1 = require("../common/error-codes.js");
//Const
const DEFAULT_BUFFER_WATERLINE = 1 << 16;
//Preprocessor
//NOTE: HTML input preprocessing
//(see: http://www.whatwg.org/specs/web-apps/current-work/multipage/parsing.html#preprocessing-the-input-stream)
class Preprocessor {
constructor(handler) {
this.handler = handler;
this.html = '';
this.pos = -1;
// NOTE: Initial `lastGapPos` is -2, to ensure `col` on initialisation is 0
this.lastGapPos = -2;
this.gapStack = [];
this.skipNextNewLine = false;
this.lastChunkWritten = false;
this.endOfChunkHit = false;
this.bufferWaterline = DEFAULT_BUFFER_WATERLINE;
this.isEol = false;
this.lineStartPos = 0;
this.droppedBufferSize = 0;
this.line = 1;
//NOTE: avoid reporting errors twice on advance/retreat
this.lastErrOffset = -1;
}
/** The column on the current line. If we just saw a gap (eg. a surrogate pair), return the index before. */
get col() {
return this.pos - this.lineStartPos + Number(this.lastGapPos !== this.pos);
}
get offset() {
return this.droppedBufferSize + this.pos;
}
getError(code, cpOffset) {
const { line, col, offset } = this;
const startCol = col + cpOffset;
const startOffset = offset + cpOffset;
return {
code,
startLine: line,
endLine: line,
startCol,
endCol: startCol,
startOffset,
endOffset: startOffset,
};
}
_err(code) {
if (this.handler.onParseError && this.lastErrOffset !== this.offset) {
this.lastErrOffset = this.offset;
this.handler.onParseError(this.getError(code, 0));
}
}
_addGap() {
this.gapStack.push(this.lastGapPos);
this.lastGapPos = this.pos;
}
_processSurrogate(cp) {
//NOTE: try to peek a surrogate pair
if (this.pos !== this.html.length - 1) {
const nextCp = this.html.charCodeAt(this.pos + 1);
if ((0, unicode_js_1.isSurrogatePair)(nextCp)) {
//NOTE: we have a surrogate pair. Peek pair character and recalculate code point.
this.pos++;
//NOTE: add a gap that should be avoided during retreat
this._addGap();
return (0, unicode_js_1.getSurrogatePairCodePoint)(cp, nextCp);
}
}
//NOTE: we are at the end of a chunk, therefore we can't infer the surrogate pair yet.
else if (!this.lastChunkWritten) {
this.endOfChunkHit = true;
return unicode_js_1.CODE_POINTS.EOF;
}
//NOTE: isolated surrogate
this._err(error_codes_js_1.ERR.surrogateInInputStream);
return cp;
}
willDropParsedChunk() {
return this.pos > this.bufferWaterline;
}
dropParsedChunk() {
if (this.willDropParsedChunk()) {
this.html = this.html.substring(this.pos);
this.lineStartPos -= this.pos;
this.droppedBufferSize += this.pos;
this.pos = 0;
this.lastGapPos = -2;
this.gapStack.length = 0;
}
}
write(chunk, isLastChunk) {
if (this.html.length > 0) {
this.html += chunk;
}
else {
this.html = chunk;
}
this.endOfChunkHit = false;
this.lastChunkWritten = isLastChunk;
}
insertHtmlAtCurrentPos(chunk) {
this.html = this.html.substring(0, this.pos + 1) + chunk + this.html.substring(this.pos + 1);
this.endOfChunkHit = false;
}
startsWith(pattern, caseSensitive) {
// Check if our buffer has enough characters
if (this.pos + pattern.length > this.html.length) {
this.endOfChunkHit = !this.lastChunkWritten;
return false;
}
if (caseSensitive) {
return this.html.startsWith(pattern, this.pos);
}
for (let i = 0; i < pattern.length; i++) {
const cp = this.html.charCodeAt(this.pos + i) | 0x20;
if (cp !== pattern.charCodeAt(i)) {
return false;
}
}
return true;
}
peek(offset) {
const pos = this.pos + offset;
if (pos >= this.html.length) {
this.endOfChunkHit = !this.lastChunkWritten;
return unicode_js_1.CODE_POINTS.EOF;
}
const code = this.html.charCodeAt(pos);
return code === unicode_js_1.CODE_POINTS.CARRIAGE_RETURN ? unicode_js_1.CODE_POINTS.LINE_FEED : code;
}
advance() {
this.pos++;
//NOTE: LF should be in the last column of the line
if (this.isEol) {
this.isEol = false;
this.line++;
this.lineStartPos = this.pos;
}
if (this.pos >= this.html.length) {
this.endOfChunkHit = !this.lastChunkWritten;
return unicode_js_1.CODE_POINTS.EOF;
}
let cp = this.html.charCodeAt(this.pos);
//NOTE: all U+000D CARRIAGE RETURN (CR) characters must be converted to U+000A LINE FEED (LF) characters
if (cp === unicode_js_1.CODE_POINTS.CARRIAGE_RETURN) {
this.isEol = true;
this.skipNextNewLine = true;
return unicode_js_1.CODE_POINTS.LINE_FEED;
}
//NOTE: any U+000A LINE FEED (LF) characters that immediately follow a U+000D CARRIAGE RETURN (CR) character
//must be ignored.
if (cp === unicode_js_1.CODE_POINTS.LINE_FEED) {
this.isEol = true;
if (this.skipNextNewLine) {
// `line` will be bumped again in the recursive call.
this.line--;
this.skipNextNewLine = false;
this._addGap();
return this.advance();
}
}
this.skipNextNewLine = false;
if ((0, unicode_js_1.isSurrogate)(cp)) {
cp = this._processSurrogate(cp);
}
//OPTIMIZATION: first check if code point is in the common allowed
//range (ASCII alphanumeric, whitespaces, big chunk of BMP)
//before going into detailed performance cost validation.
const isCommonValidRange = this.handler.onParseError === null ||
(cp > 0x1f && cp < 0x7f) ||
cp === unicode_js_1.CODE_POINTS.LINE_FEED ||
cp === unicode_js_1.CODE_POINTS.CARRIAGE_RETURN ||
(cp > 0x9f && cp < 64976);
if (!isCommonValidRange) {
this._checkForProblematicCharacters(cp);
}
return cp;
}
_checkForProblematicCharacters(cp) {
if ((0, unicode_js_1.isControlCodePoint)(cp)) {
this._err(error_codes_js_1.ERR.controlCharacterInInputStream);
}
else if ((0, unicode_js_1.isUndefinedCodePoint)(cp)) {
this._err(error_codes_js_1.ERR.noncharacterInInputStream);
}
}
retreat(count) {
this.pos -= count;
while (this.pos < this.lastGapPos) {
this.lastGapPos = this.gapStack.pop();
this.pos--;
}
this.isEol = false;
}
}
exports.Preprocessor = Preprocessor;