fchat-rising/bbcode/parser.ts

258 lines
10 KiB
TypeScript

export abstract class BBCodeTag {
noClosingTag = false;
allowedTags: {[tag: string]: boolean | undefined} | undefined;
constructor(public tag: string, tagList?: string[]) {
if(tagList !== undefined)
this.setAllowedTags(tagList);
}
isAllowed(tag: string): boolean {
return this.allowedTags === undefined || this.allowedTags[tag] !== undefined;
}
setAllowedTags(allowed: string[]): void {
this.allowedTags = {};
for(const tag of allowed)
this.allowedTags[tag] = true;
}
//tslint:disable-next-line:no-empty
afterClose(_: BBCodeParser, __: HTMLElement, ___: HTMLElement | undefined, ____?: string): void {
}
abstract createElement(parser: BBCodeParser, parent: HTMLElement, param: string): HTMLElement | undefined;
}
export class BBCodeSimpleTag extends BBCodeTag {
constructor(tag: string, private elementName: keyof HTMLElementTagNameMap, private classes?: string[], tagList?: string[]) {
super(tag, tagList);
}
createElement(parser: BBCodeParser, parent: HTMLElement, param: string): HTMLElement {
if(param.length > 0)
parser.warning('Unexpected parameter');
const el = <HTMLElement>parser.createElement(this.elementName);
if(this.classes !== undefined && this.classes.length > 0)
el.className = this.classes.join(' ');
parent.appendChild(el);
/*tslint:disable-next-line:no-unsafe-any*/// false positive
return el;
}
}
export type CustomElementCreator = (parser: BBCodeParser, parent: HTMLElement, param: string) => HTMLElement | undefined;
export type CustomCloser = (parser: BBCodeParser, current: HTMLElement, parent: HTMLElement, param: string) => void;
export class BBCodeCustomTag extends BBCodeTag {
constructor(tag: string, private customCreator: CustomElementCreator, private customCloser?: CustomCloser, tagList?: string[]) {
super(tag, tagList);
}
createElement(parser: BBCodeParser, parent: HTMLElement, param: string): HTMLElement | undefined {
return this.customCreator(parser, parent, param);
}
afterClose(parser: BBCodeParser, current: HTMLElement, parent: HTMLElement, param: string): void {
if(this.customCloser !== undefined)
this.customCloser(parser, current, parent, param);
}
}
enum BufferType { Raw, Tag }
class ParserTag {
constructor(public tag: string, public param: string, public element: HTMLElement, public parent: HTMLElement | undefined,
public line: number, public column: number) {
}
appendElement(child: HTMLElement): void {
this.element.appendChild(child);
}
append(content: string, start: number, end: number): void {
if(content.length === 0)
return;
this.element.appendChild(document.createTextNode(content.substring(start, end)));
}
}
export class BBCodeParser {
private _warnings: string[] = [];
private _tags: {[tag: string]: BBCodeTag | undefined} = {};
private _line = -1;
private _column = -1;
private _currentTag!: ParserTag;
private _storeWarnings = false;
parseEverything(input: string): HTMLElement {
if(input.length === 0)
return this.createElement('span');
this._warnings = [];
this._line = 1;
this._column = 1;
const stack: ParserTag[] = this.parse(input, 0, input.length);
for(let i = stack.length - 1; i > 0; i--) {
this._currentTag = <ParserTag>stack.pop();
this.warning('Automatically closing tag at end of input.');
}
if(process.env.NODE_ENV !== 'production' && this._warnings.length > 0)
console.log(this._warnings);
return stack[0].element;
}
createElement<K extends keyof HTMLElementTagNameMap>(tag: K): HTMLElementTagNameMap[K] {
return document.createElement(tag);
}
addTag(tag: string, impl: BBCodeTag): void {
this._tags[tag] = impl;
}
removeTag(tag: string): void {
delete this._tags[tag];
}
get warnings(): ReadonlyArray<string> {
return this._warnings;
}
set storeWarnings(store: boolean) {
this._storeWarnings = store;
if(!store)
this._warnings = [];
}
warning(message: string): void {
if(!this._storeWarnings)
return;
const cur = this._currentTag;
const newMessage = `Error on ${this._line}:${this._column} while inside tag [${cur.tag} @ ${cur.line}:${cur.column}]: ${message}`;
this._warnings.push(newMessage);
}
private parse(input: string, start: number, end: number): ParserTag[] {
const ignoreClosing: {[key: string]: number} = {};
function ignoreNextClosingTag(tagName: string): void {
//tslint:disable-next-line:strict-boolean-expressions
ignoreClosing[tagName] = (ignoreClosing[tagName] || 0) + 1;
}
const stack: ParserTag[] = [];
function stackTop(): ParserTag {
return stack[stack.length - 1];
}
function quickReset(i: number): void {
stackTop().append(input, start, i + 1);
start = i + 1;
curType = BufferType.Raw;
}
let curType: BufferType = BufferType.Raw;
// Root tag collects output.
const rootTag = new ParserTag('<root>', '', this.createElement('span'), undefined, 1, 1);
stack.push(rootTag);
this._currentTag = rootTag;
let paramStart = -1;
for(let i = start; i < end; ++i) {
const c = input[i];
++this._column;
if(c === '\n') {
++this._line;
this._column = 1;
quickReset(i);
stackTop().appendElement(this.createElement('br'));
}
switch(curType) {
case BufferType.Raw:
if(c === '[') {
stackTop().append(input, start, i);
start = i;
curType = BufferType.Tag;
}
break;
case BufferType.Tag:
if(c === '[') {
stackTop().append(input, start, i);
start = i;
} else if(c === '=' && paramStart === -1)
paramStart = i;
else if(c === ']') {
const paramIndex = paramStart === -1 ? i : paramStart;
let tagKey = input.substring(start + 1, paramIndex).trim();
if(tagKey.length === 0) {
quickReset(i);
continue;
}
let param = '';
if(paramStart !== -1)
param = input.substring(paramStart + 1, i).trim();
paramStart = -1;
const close = tagKey[0] === '/';
if(close) tagKey = tagKey.substr(1).trim();
if(typeof this._tags[tagKey] === 'undefined') {
quickReset(i);
continue;
}
if(!close) {
let allowed = true;
for(let k = stack.length - 1; k > 0; --k) {
allowed = allowed && this._tags[stack[k].tag]!.isAllowed(tagKey);
if(!allowed)
break;
}
const tag = this._tags[tagKey]!;
if(!allowed) {
ignoreNextClosingTag(tagKey);
quickReset(i);
continue;
}
const parent = stackTop().element;
const el: HTMLElement | undefined = tag.createElement(this, parent, param);
if(el === undefined) {
quickReset(i);
continue;
}
(<HTMLElement & {bbcodeTag: string}>el).bbcodeTag = tagKey;
if(param.length > 0) (<HTMLElement & {bbcodeParam: string}>el).bbcodeParam = param;
if(!this._tags[tagKey]!.noClosingTag)
stack.push(new ParserTag(tagKey, param, el, parent, this._line, this._column));
} else if(ignoreClosing[tagKey] > 0) {
ignoreClosing[tagKey] -= 1;
stackTop().append(input, start, i + 1);
} else {
let closed = false;
for(let k = stack.length - 1; k >= 0; --k) {
if(stack[k].tag !== tagKey) continue;
for(let y = stack.length - 1; y >= k; --y) {
const closeTag = <ParserTag>stack.pop();
this._currentTag = closeTag;
if(y > k)
this.warning(`Unexpected closing ${tagKey} tag. Needed ${closeTag.tag} tag instead.`);
this._tags[closeTag.tag]!.afterClose(this, closeTag.element, closeTag.parent, closeTag.param);
}
this._currentTag = stackTop();
closed = true;
break;
}
if(!closed) {
this.warning(`Found closing ${tagKey} tag that was never opened.`);
stackTop().append(input, start, i + 1);
}
}
start = i + 1;
curType = BufferType.Raw;
}
}
}
if(start < input.length)
stackTop().append(input, start, input.length);
return stack;
}
}