package org.jsoup.parser;

import org.jsoup.helper.Validate;

import java.util.HashMap;

import java.util.Map;

/**

* HTML Tag capabilities.

*

* @author Jonathan Hedley, jonathan@hedley.net

*/

public class Tag {

private static final Map<String, Tag> tags = new HashMap<String, Tag>(); // map of known tags

private String tagName;

private boolean isBlock = true; // block or inline

private boolean formatAsBlock = true; // should be formatted as a block

private boolean canContainBlock = true; // Can this tag hold block level tags?

private boolean canContainInline = true; // only pcdata if not

private boolean empty = false; // can hold nothing; e.g. img

private boolean selfClosing = false; // can self close (<foo />). used for unknown tags that self close, without forcing them as empty.

private boolean preserveWhitespace = false; // for pre, textarea, script etc

private boolean formList = false; // a control that appears in forms: input, textarea, output etc

private boolean formSubmit = false; // a control that can be submitted in a form: input etc

private Tag(String tagName) {

this.tagName = tagName;

}

/**

* Get this tag's name.

*

* @return the tag's name

*/

public String getName() {

return tagName;

}

/**

* Get a Tag by name. If not previously defined (unknown), returns a new generic tag, that can do anything.

* <p>

* Pre-defined tags (P, DIV etc) will be ==, but unknown tags are not registered and will only .equals().

* </p>

*

* @param tagName Name of tag, e.g. "p". Case insensitive.

* @param settings used to control tag name sensitivity

* @return The tag, either defined or new generic.

*/

public static Tag valueOf(String tagName, ParseSettings settings) {

Validate.notNull(tagName);

Tag tag = tags.get(tagName);

if (tag == null) {

tagName = settings.normalizeTag(tagName);

Validate.notEmpty(tagName);

tag = tags.get(tagName);

if (tag == null) {

// not defined: create default; go anywhere, do anything! (incl be inside a <p>)

tag = new Tag(tagName);

tag.isBlock = false;

tag.canContainBlock = true;

}

}

return tag;

}

/**

* Get a Tag by name. If not previously defined (unknown), returns a new generic tag, that can do anything.

* <p>

* Pre-defined tags (P, DIV etc) will be ==, but unknown tags are not registered and will only .equals().

* </p>

*

* @param tagName Name of tag, e.g. "p". <b>Case sensitive</b>.

* @return The tag, either defined or new generic.

*/

public static Tag valueOf(String tagName) {

return valueOf(tagName, ParseSettings.preserveCase);

}

/**

* Gets if this is a block tag.

*

* @return if block tag

*/

public boolean isBlock() {

return isBlock;

}

/**

* Gets if this tag should be formatted as a block (or as inline)

*

* @return if should be formatted as block or inline

*/

public boolean formatAsBlock() {

return formatAsBlock;

}

/**

* Gets if this tag can contain block tags.

*

* @return if tag can contain block tags

*/

public boolean canContainBlock() {

return canContainBlock;

}

/**

* Gets if this tag is an inline tag.

*

* @return if this tag is an inline tag.

*/

public boolean isInline() {

return !isBlock;

}

/**

* Gets if this tag is a data only tag.

*

* @return if this tag is a data only tag

*/

public boolean isData() {

return !canContainInline && !isEmpty();

}

/**

* Get if this is an empty tag

*

* @return if this is an empty tag

*/

public boolean isEmpty() {

return empty;

}

/**

* Get if this tag is self closing.

*

* @return if this tag should be output as self closing.

*/

public boolean isSelfClosing() {

return empty || selfClosing;

}

/**

* Get if this is a pre-defined tag, or was auto created on parsing.

*

* @return if a known tag

*/

public boolean isKnownTag() {

return tags.containsKey(tagName);

}

/**

* Check if this tagname is a known tag.

*

* @param tagName name of tag

* @return if known HTML tag

*/

public static boolean isKnownTag(String tagName) {

return tags.containsKey(tagName);

}

/**

* Get if this tag should preserve whitespace within child text nodes.

*

* @return if preserve whitepace

*/

public boolean preserveWhitespace() {

return preserveWhitespace;

}

/**

* Get if this tag represents a control associated with a form. E.g. input, textarea, output

* @return if associated with a form

*/

public boolean isFormListed() {

return formList;

}

/**

* Get if this tag represents an element that should be submitted with a form. E.g. input, option

* @return if submittable with a form

*/

public boolean isFormSubmittable() {

return formSubmit;

}

Tag setSelfClosing() {

selfClosing = true;

return this;

}

@Override

public boolean equals(Object o) {

if (this == o) return true;

if (!(o instanceof Tag)) return false;

Tag tag = (Tag) o;

if (!tagName.equals(tag.tagName)) return false;

if (canContainBlock != tag.canContainBlock) return false;

if (canContainInline != tag.canContainInline) return false;

if (empty != tag.empty) return false;

if (formatAsBlock != tag.formatAsBlock) return false;

if (isBlock != tag.isBlock) return false;

if (preserveWhitespace != tag.preserveWhitespace) return false;

if (selfClosing != tag.selfClosing) return false;

if (formList != tag.formList) return false;

return formSubmit == tag.formSubmit;

}

@Override

public int hashCode() {

int result = tagName.hashCode();

result = 31 * result + (isBlock ? 1 : 0);

result = 31 * result + (formatAsBlock ? 1 : 0);

result = 31 * result + (canContainBlock ? 1 : 0);

result = 31 * result + (canContainInline ? 1 : 0);

result = 31 * result + (empty ? 1 : 0);

result = 31 * result + (selfClosing ? 1 : 0);

result = 31 * result + (preserveWhitespace ? 1 : 0);

result = 31 * result + (formList ? 1 : 0);

result = 31 * result + (formSubmit ? 1 : 0);

return result;

}

@Override

public String toString() {

return tagName;

}

// internal static initialisers:

// prepped from http://www.w3.org/TR/REC-html40/sgml/dtd.html and other sources

private static final String[] blockTags = {

"html", "head", "body", "frameset", "script", "noscript", "style", "meta", "link", "title", "frame",

"noframes", "section", "nav", "aside", "hgroup", "header", "footer", "p", "h1", "h2", "h3", "h4", "h5", "h6",

"ul", "ol", "pre", "div", "blockquote", "hr", "address", "figure", "figcaption", "form", "fieldset", "ins",

"del", "s", "dl", "dt", "dd", "li", "table", "caption", "thead", "tfoot", "tbody", "colgroup", "col", "tr", "th",

"td", "video", "audio", "canvas", "details", "menu", "plaintext", "template", "article", "main",

"svg", "math"

};

private static final String[] inlineTags = {

"object", "base", "font", "tt", "i", "b", "u", "big", "small", "em", "strong", "dfn", "code", "samp", "kbd",

"var", "cite", "abbr", "time", "acronym", "mark", "ruby", "rt", "rp", "a", "img", "br", "wbr", "map", "q",

"sub", "sup", "bdo", "iframe", "embed", "span", "input", "select", "textarea", "label", "button", "optgroup",

"option", "legend", "datalist", "keygen", "output", "progress", "meter", "area", "param", "source", "track",

"summary", "command", "device", "area", "basefont", "bgsound", "menuitem", "param", "source", "track",

"data", "bdi"

};

private static final String[] emptyTags = {

"meta", "link", "base", "frame", "img", "br", "wbr", "embed", "hr", "input", "keygen", "col", "command",

"device", "area", "basefont", "bgsound", "menuitem", "param", "source", "track"

};

private static final String[] formatAsInlineTags = {

"title", "a", "p", "h1", "h2", "h3", "h4", "h5", "h6", "pre", "address", "li", "th", "td", "script", "style",

"ins", "del", "s"

};

private static final String[] preserveWhitespaceTags = {

"pre", "plaintext", "title", "textarea"

// script is not here as it is a data node, which always preserve whitespace

};

// todo: I think we just need submit tags, and can scrub listed

private static final String[] formListedTags = {

"button", "fieldset", "input", "keygen", "object", "output", "select", "textarea"

};

private static final String[] formSubmitTags = {

"input", "keygen", "object", "select", "textarea"

};

static {

// creates

for (String tagName : blockTags) {

Tag tag = new Tag(tagName);

register(tag);

}

for (String tagName : inlineTags) {

Tag tag = new Tag(tagName);

tag.isBlock = false;

tag.canContainBlock = false;

tag.formatAsBlock = false;

register(tag);

}

// mods:

for (String tagName : emptyTags) {

Tag tag = tags.get(tagName);

Validate.notNull(tag);

tag.canContainBlock = false;

tag.canContainInline = false;

tag.empty = true;

}

for (String tagName : formatAsInlineTags) {

Tag tag = tags.get(tagName);

Validate.notNull(tag);

tag.formatAsBlock = false;

}

for (String tagName : preserveWhitespaceTags) {

Tag tag = tags.get(tagName);

Validate.notNull(tag);

tag.preserveWhitespace = true;

}

for (String tagName : formListedTags) {

Tag tag = tags.get(tagName);

Validate.notNull(tag);

tag.formList = true;

}

for (String tagName : formSubmitTags) {

Tag tag = tags.get(tagName);

Validate.notNull(tag);

tag.formSubmit = true;

}

}

private static void register(Tag tag) {

tags.put(tag.tagName, tag);

}

}