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1'use strict';
2
3const HTML = require('../common/html');
4
5//Aliases
6const $ = HTML.TAG_NAMES;
7const NS = HTML.NAMESPACES;
8
9//Element utils
10
11//OPTIMIZATION: Integer comparisons are low-cost, so we can use very fast tag name length filters here.
12//It's faster than using dictionary.
13function isImpliedEndTagRequired(tn) {
14    switch (tn.length) {
15        case 1:
16            return tn === $.P;
17
18        case 2:
19            return tn === $.RB || tn === $.RP || tn === $.RT || tn === $.DD || tn === $.DT || tn === $.LI;
20
21        case 3:
22            return tn === $.RTC;
23
24        case 6:
25            return tn === $.OPTION;
26
27        case 8:
28            return tn === $.OPTGROUP;
29    }
30
31    return false;
32}
33
34function isImpliedEndTagRequiredThoroughly(tn) {
35    switch (tn.length) {
36        case 1:
37            return tn === $.P;
38
39        case 2:
40            return (
41                tn === $.RB ||
42                tn === $.RP ||
43                tn === $.RT ||
44                tn === $.DD ||
45                tn === $.DT ||
46                tn === $.LI ||
47                tn === $.TD ||
48                tn === $.TH ||
49                tn === $.TR
50            );
51
52        case 3:
53            return tn === $.RTC;
54
55        case 5:
56            return tn === $.TBODY || tn === $.TFOOT || tn === $.THEAD;
57
58        case 6:
59            return tn === $.OPTION;
60
61        case 7:
62            return tn === $.CAPTION;
63
64        case 8:
65            return tn === $.OPTGROUP || tn === $.COLGROUP;
66    }
67
68    return false;
69}
70
71function isScopingElement(tn, ns) {
72    switch (tn.length) {
73        case 2:
74            if (tn === $.TD || tn === $.TH) {
75                return ns === NS.HTML;
76            } else if (tn === $.MI || tn === $.MO || tn === $.MN || tn === $.MS) {
77                return ns === NS.MATHML;
78            }
79
80            break;
81
82        case 4:
83            if (tn === $.HTML) {
84                return ns === NS.HTML;
85            } else if (tn === $.DESC) {
86                return ns === NS.SVG;
87            }
88
89            break;
90
91        case 5:
92            if (tn === $.TABLE) {
93                return ns === NS.HTML;
94            } else if (tn === $.MTEXT) {
95                return ns === NS.MATHML;
96            } else if (tn === $.TITLE) {
97                return ns === NS.SVG;
98            }
99
100            break;
101
102        case 6:
103            return (tn === $.APPLET || tn === $.OBJECT) && ns === NS.HTML;
104
105        case 7:
106            return (tn === $.CAPTION || tn === $.MARQUEE) && ns === NS.HTML;
107
108        case 8:
109            return tn === $.TEMPLATE && ns === NS.HTML;
110
111        case 13:
112            return tn === $.FOREIGN_OBJECT && ns === NS.SVG;
113
114        case 14:
115            return tn === $.ANNOTATION_XML && ns === NS.MATHML;
116    }
117
118    return false;
119}
120
121//Stack of open elements
122class OpenElementStack {
123    constructor(document, treeAdapter) {
124        this.stackTop = -1;
125        this.items = [];
126        this.current = document;
127        this.currentTagName = null;
128        this.currentTmplContent = null;
129        this.tmplCount = 0;
130        this.treeAdapter = treeAdapter;
131    }
132
133    //Index of element
134    _indexOf(element) {
135        let idx = -1;
136
137        for (let i = this.stackTop; i >= 0; i--) {
138            if (this.items[i] === element) {
139                idx = i;
140                break;
141            }
142        }
143        return idx;
144    }
145
146    //Update current element
147    _isInTemplate() {
148        return this.currentTagName === $.TEMPLATE && this.treeAdapter.getNamespaceURI(this.current) === NS.HTML;
149    }
150
151    _updateCurrentElement() {
152        this.current = this.items[this.stackTop];
153        this.currentTagName = this.current && this.treeAdapter.getTagName(this.current);
154
155        this.currentTmplContent = this._isInTemplate() ? this.treeAdapter.getTemplateContent(this.current) : null;
156    }
157
158    //Mutations
159    push(element) {
160        this.items[++this.stackTop] = element;
161        this._updateCurrentElement();
162
163        if (this._isInTemplate()) {
164            this.tmplCount++;
165        }
166    }
167
168    pop() {
169        this.stackTop--;
170
171        if (this.tmplCount > 0 && this._isInTemplate()) {
172            this.tmplCount--;
173        }
174
175        this._updateCurrentElement();
176    }
177
178    replace(oldElement, newElement) {
179        const idx = this._indexOf(oldElement);
180
181        this.items[idx] = newElement;
182
183        if (idx === this.stackTop) {
184            this._updateCurrentElement();
185        }
186    }
187
188    insertAfter(referenceElement, newElement) {
189        const insertionIdx = this._indexOf(referenceElement) + 1;
190
191        this.items.splice(insertionIdx, 0, newElement);
192
193        if (insertionIdx === ++this.stackTop) {
194            this._updateCurrentElement();
195        }
196    }
197
198    popUntilTagNamePopped(tagName) {
199        while (this.stackTop > -1) {
200            const tn = this.currentTagName;
201            const ns = this.treeAdapter.getNamespaceURI(this.current);
202
203            this.pop();
204
205            if (tn === tagName && ns === NS.HTML) {
206                break;
207            }
208        }
209    }
210
211    popUntilElementPopped(element) {
212        while (this.stackTop > -1) {
213            const poppedElement = this.current;
214
215            this.pop();
216
217            if (poppedElement === element) {
218                break;
219            }
220        }
221    }
222
223    popUntilNumberedHeaderPopped() {
224        while (this.stackTop > -1) {
225            const tn = this.currentTagName;
226            const ns = this.treeAdapter.getNamespaceURI(this.current);
227
228            this.pop();
229
230            if (
231                tn === $.H1 ||
232                tn === $.H2 ||
233                tn === $.H3 ||
234                tn === $.H4 ||
235                tn === $.H5 ||
236                (tn === $.H6 && ns === NS.HTML)
237            ) {
238                break;
239            }
240        }
241    }
242
243    popUntilTableCellPopped() {
244        while (this.stackTop > -1) {
245            const tn = this.currentTagName;
246            const ns = this.treeAdapter.getNamespaceURI(this.current);
247
248            this.pop();
249
250            if (tn === $.TD || (tn === $.TH && ns === NS.HTML)) {
251                break;
252            }
253        }
254    }
255
256    popAllUpToHtmlElement() {
257        //NOTE: here we assume that root <html> element is always first in the open element stack, so
258        //we perform this fast stack clean up.
259        this.stackTop = 0;
260        this._updateCurrentElement();
261    }
262
263    clearBackToTableContext() {
264        while (
265            (this.currentTagName !== $.TABLE && this.currentTagName !== $.TEMPLATE && this.currentTagName !== $.HTML) ||
266            this.treeAdapter.getNamespaceURI(this.current) !== NS.HTML
267        ) {
268            this.pop();
269        }
270    }
271
272    clearBackToTableBodyContext() {
273        while (
274            (this.currentTagName !== $.TBODY &&
275                this.currentTagName !== $.TFOOT &&
276                this.currentTagName !== $.THEAD &&
277                this.currentTagName !== $.TEMPLATE &&
278                this.currentTagName !== $.HTML) ||
279            this.treeAdapter.getNamespaceURI(this.current) !== NS.HTML
280        ) {
281            this.pop();
282        }
283    }
284
285    clearBackToTableRowContext() {
286        while (
287            (this.currentTagName !== $.TR && this.currentTagName !== $.TEMPLATE && this.currentTagName !== $.HTML) ||
288            this.treeAdapter.getNamespaceURI(this.current) !== NS.HTML
289        ) {
290            this.pop();
291        }
292    }
293
294    remove(element) {
295        for (let i = this.stackTop; i >= 0; i--) {
296            if (this.items[i] === element) {
297                this.items.splice(i, 1);
298                this.stackTop--;
299                this._updateCurrentElement();
300                break;
301            }
302        }
303    }
304
305    //Search
306    tryPeekProperlyNestedBodyElement() {
307        //Properly nested <body> element (should be second element in stack).
308        const element = this.items[1];
309
310        return element && this.treeAdapter.getTagName(element) === $.BODY ? element : null;
311    }
312
313    contains(element) {
314        return this._indexOf(element) > -1;
315    }
316
317    getCommonAncestor(element) {
318        let elementIdx = this._indexOf(element);
319
320        return --elementIdx >= 0 ? this.items[elementIdx] : null;
321    }
322
323    isRootHtmlElementCurrent() {
324        return this.stackTop === 0 && this.currentTagName === $.HTML;
325    }
326
327    //Element in scope
328    hasInScope(tagName) {
329        for (let i = this.stackTop; i >= 0; i--) {
330            const tn = this.treeAdapter.getTagName(this.items[i]);
331            const ns = this.treeAdapter.getNamespaceURI(this.items[i]);
332
333            if (tn === tagName && ns === NS.HTML) {
334                return true;
335            }
336
337            if (isScopingElement(tn, ns)) {
338                return false;
339            }
340        }
341
342        return true;
343    }
344
345    hasNumberedHeaderInScope() {
346        for (let i = this.stackTop; i >= 0; i--) {
347            const tn = this.treeAdapter.getTagName(this.items[i]);
348            const ns = this.treeAdapter.getNamespaceURI(this.items[i]);
349
350            if (
351                (tn === $.H1 || tn === $.H2 || tn === $.H3 || tn === $.H4 || tn === $.H5 || tn === $.H6) &&
352                ns === NS.HTML
353            ) {
354                return true;
355            }
356
357            if (isScopingElement(tn, ns)) {
358                return false;
359            }
360        }
361
362        return true;
363    }
364
365    hasInListItemScope(tagName) {
366        for (let i = this.stackTop; i >= 0; i--) {
367            const tn = this.treeAdapter.getTagName(this.items[i]);
368            const ns = this.treeAdapter.getNamespaceURI(this.items[i]);
369
370            if (tn === tagName && ns === NS.HTML) {
371                return true;
372            }
373
374            if (((tn === $.UL || tn === $.OL) && ns === NS.HTML) || isScopingElement(tn, ns)) {
375                return false;
376            }
377        }
378
379        return true;
380    }
381
382    hasInButtonScope(tagName) {
383        for (let i = this.stackTop; i >= 0; i--) {
384            const tn = this.treeAdapter.getTagName(this.items[i]);
385            const ns = this.treeAdapter.getNamespaceURI(this.items[i]);
386
387            if (tn === tagName && ns === NS.HTML) {
388                return true;
389            }
390
391            if ((tn === $.BUTTON && ns === NS.HTML) || isScopingElement(tn, ns)) {
392                return false;
393            }
394        }
395
396        return true;
397    }
398
399    hasInTableScope(tagName) {
400        for (let i = this.stackTop; i >= 0; i--) {
401            const tn = this.treeAdapter.getTagName(this.items[i]);
402            const ns = this.treeAdapter.getNamespaceURI(this.items[i]);
403
404            if (ns !== NS.HTML) {
405                continue;
406            }
407
408            if (tn === tagName) {
409                return true;
410            }
411
412            if (tn === $.TABLE || tn === $.TEMPLATE || tn === $.HTML) {
413                return false;
414            }
415        }
416
417        return true;
418    }
419
420    hasTableBodyContextInTableScope() {
421        for (let i = this.stackTop; i >= 0; i--) {
422            const tn = this.treeAdapter.getTagName(this.items[i]);
423            const ns = this.treeAdapter.getNamespaceURI(this.items[i]);
424
425            if (ns !== NS.HTML) {
426                continue;
427            }
428
429            if (tn === $.TBODY || tn === $.THEAD || tn === $.TFOOT) {
430                return true;
431            }
432
433            if (tn === $.TABLE || tn === $.HTML) {
434                return false;
435            }
436        }
437
438        return true;
439    }
440
441    hasInSelectScope(tagName) {
442        for (let i = this.stackTop; i >= 0; i--) {
443            const tn = this.treeAdapter.getTagName(this.items[i]);
444            const ns = this.treeAdapter.getNamespaceURI(this.items[i]);
445
446            if (ns !== NS.HTML) {
447                continue;
448            }
449
450            if (tn === tagName) {
451                return true;
452            }
453
454            if (tn !== $.OPTION && tn !== $.OPTGROUP) {
455                return false;
456            }
457        }
458
459        return true;
460    }
461
462    //Implied end tags
463    generateImpliedEndTags() {
464        while (isImpliedEndTagRequired(this.currentTagName)) {
465            this.pop();
466        }
467    }
468
469    generateImpliedEndTagsThoroughly() {
470        while (isImpliedEndTagRequiredThoroughly(this.currentTagName)) {
471            this.pop();
472        }
473    }
474
475    generateImpliedEndTagsWithExclusion(exclusionTagName) {
476        while (isImpliedEndTagRequired(this.currentTagName) && this.currentTagName !== exclusionTagName) {
477            this.pop();
478        }
479    }
480}
481
482module.exports = OpenElementStack;
483