let traverseForward = check => {
let location;
// Backward loop to determine the beginning location of the selector.
do {
let lineText = sourceArray[line];
if (line == caret.line) {
lineText = lineText.substring(caret.ch);
}
let prevToken = undefined;
let tokens = cssTokenizer(lineText);
let found = false;
let ech = line == caret.line ? caret.ch : 0;
for (let token of tokens) {
// If the line is completely spaces, handle it differently
if (lineText.trim() == "") {
limitedSource += lineText;
} else {
limitedSource += sourceArray[line]
.substring(ech + token.startOffset,
ech + token.endOffset);
}
// Whitespace cannot change state.
if (token.tokenType == "whitespace") {
prevToken = token;
continue;
}
let state = this.resolveState(limitedSource, {
line: line,
ch: token.endOffset + ech
});
if (check(state)) {
if (prevToken && prevToken.tokenType == "whitespace") {
token = prevToken;
}
location = {
line: line,
ch: token.startOffset + ech
};
found = true;
break;
}
prevToken = token;
}
limitedSource += "\n";
if (found) {
break;
}
} while (line++ < sourceArray.length);
return location;
};
/**
* Tokenizes a CSS Filter value and returns an array of {name, value} pairs.
*
* @param {String} css CSS Filter value to be parsed
* @return {Array} An array of {name, value} pairs
*/
function tokenizeFilterValue(css) {
let filters = [];
let depth = 0;
if (SPECIAL_VALUES.has(css)) {
return filters;
}
let state = "initial";
let name;
let contents;
for (let token of cssTokenizer(css)) {
switch (state) {
case "initial":
if (token.tokenType === "function") {
name = token.text;
contents = "";
state = "function";
depth = 1;
} else if (token.tokenType === "url" || token.tokenType === "bad_url") {
// Extract the quoting style from the url.
let originalText = css.substring(token.startOffset, token.endOffset);
let [, quote] = /^url\([ \t\r\n\f]*(["']?)/i.exec(originalText);
filters.push({name: "url", value: token.text.trim(), quote: quote});
// Leave state as "initial" because the URL token includes
// the trailing close paren.
}
break;
case "function":
if (token.tokenType === "symbol" && token.text === ")") {
--depth;
if (depth === 0) {
filters.push({name: name, value: contents.trim()});
state = "initial";
break;
}
}
contents += css.substring(token.startOffset, token.endOffset);
if (token.tokenType === "function" ||
(token.tokenType === "symbol" && token.text === "(")) {
++depth;
}
break;
}
}
return filters;
}
let traverseBackwards = (check, isValue) => {
let location;
// Backward loop to determine the beginning location of the selector.
do {
let lineText = sourceArray[line];
if (line == caret.line) {
lineText = lineText.substring(0, caret.ch);
}
let tokens = Array.from(cssTokenizer(lineText));
let found = false;
for (let i = tokens.length - 1; i >= 0; i--) {
let token = tokens[i];
// If the line is completely spaces, handle it differently
if (lineText.trim() == "") {
limitedSource = limitedSource.slice(0, -1 * lineText.length);
} else {
let length = token.endOffset - token.startOffset;
limitedSource = limitedSource.slice(0, -1 * length);
}
// Whitespace cannot change state.
if (token.tokenType == "whitespace") {
continue;
}
let state = this.resolveState(limitedSource, {
line: line,
ch: token.startOffset
});
if (check(state)) {
if (tokens[i + 1] && tokens[i + 1].tokenType == "whitespace") {
token = tokens[i + 1];
}
location = {
line: line,
ch: isValue ? token.endOffset : token.startOffset
};
found = true;
break;
}
}
limitedSource = limitedSource.slice(0, -1);
if (found) {
break;
}
} while (line-- >= 0);
return location;
};
/**
* Tokenizes a CSS Filter value and returns an array of {name, value} pairs.
*
* @param {String} css CSS Filter value to be parsed
* @return {Array} An array of {name, value} pairs
*/
function tokenizeFilterValue(css) {
let filters = [];
let depth = 0;
if (css === "none") {
return filters;
}
let state = "initial";
let name;
let contents;
for (let token of cssTokenizer(css)) {
switch (state) {
case "initial":
if (token.tokenType === "function") {
name = token.text;
contents = "";
state = "function";
depth = 1;
} else if (token.tokenType === "url" || token.tokenType === "bad_url") {
filters.push({name: "url", value: token.text.trim()});
// Leave state as "initial" because the URL token includes
// the trailing close paren.
}
break;
case "function":
if (token.tokenType === "symbol" && token.text === ")") {
--depth;
if (depth === 0) {
filters.push({name: name, value: contents.trim()});
state = "initial";
break;
}
}
contents += css.substring(token.startOffset, token.endOffset);
if (token.tokenType === "function" ||
(token.tokenType === "symbol" && token.text === "(")) {
++depth;
}
break;
}
}
return filters;
}
getInfoAt: function (source, caret) {
// Limits the input source till the {line, ch} caret position
function limit(source, {line, ch}) {
line++;
let list = source.split("\n");
if (list.length < line) {
return source;
}
if (line == 1) {
return list[0].slice(0, ch);
}
return [...list.slice(0, line - 1),
list[line - 1].slice(0, ch)].join("\n");
}
// Get the state at the given line, ch
let state = this.resolveState(limit(source, caret), caret);
let propertyName = this.propertyName;
let {line, ch} = caret;
let sourceArray = source.split("\n");
let limitedSource = limit(source, caret);
/**
* Method to traverse forwards from the caret location to figure out the
* ending point of a selector or css value.
*
* @param {function} check
* A method which takes the current state as an input and determines
* whether the state changed or not.
*/
let traverseForward = check => {
let location;
// Backward loop to determine the beginning location of the selector.
do {
let lineText = sourceArray[line];
if (line == caret.line) {
lineText = lineText.substring(caret.ch);
}
let prevToken = undefined;
let tokens = cssTokenizer(lineText);
let found = false;
let ech = line == caret.line ? caret.ch : 0;
for (let token of tokens) {
// If the line is completely spaces, handle it differently
if (lineText.trim() == "") {
limitedSource += lineText;
} else {
limitedSource += sourceArray[line]
.substring(ech + token.startOffset,
ech + token.endOffset);
}
// Whitespace cannot change state.
if (token.tokenType == "whitespace") {
prevToken = token;
continue;
}
let state = this.resolveState(limitedSource, {
line: line,
ch: token.endOffset + ech
});
if (check(state)) {
if (prevToken && prevToken.tokenType == "whitespace") {
token = prevToken;
}
location = {
line: line,
ch: token.startOffset + ech
};
found = true;
break;
}
prevToken = token;
}
limitedSource += "\n";
if (found) {
break;
}
} while (line++ < sourceArray.length);
return location;
};
/**
* Method to traverse backwards from the caret location to figure out the
* starting point of a selector or css value.
*
* @param {function} check
* A method which takes the current state as an input and determines
* whether the state changed or not.
* @param {boolean} isValue
* true if the traversal is being done for a css value state.
*/
let traverseBackwards = (check, isValue) => {
let location;
// Backward loop to determine the beginning location of the selector.
do {
let lineText = sourceArray[line];
if (line == caret.line) {
lineText = lineText.substring(0, caret.ch);
}
let tokens = Array.from(cssTokenizer(lineText));
let found = false;
for (let i = tokens.length - 1; i >= 0; i--) {
let token = tokens[i];
// If the line is completely spaces, handle it differently
if (lineText.trim() == "") {
limitedSource = limitedSource.slice(0, -1 * lineText.length);
} else {
let length = token.endOffset - token.startOffset;
limitedSource = limitedSource.slice(0, -1 * length);
}
// Whitespace cannot change state.
if (token.tokenType == "whitespace") {
continue;
}
let state = this.resolveState(limitedSource, {
line: line,
ch: token.startOffset
});
if (check(state)) {
if (tokens[i + 1] && tokens[i + 1].tokenType == "whitespace") {
token = tokens[i + 1];
}
location = {
line: line,
ch: isValue ? token.endOffset : token.startOffset
};
found = true;
break;
}
}
limitedSource = limitedSource.slice(0, -1);
if (found) {
break;
}
} while (line-- >= 0);
return location;
};
if (state == CSS_STATES.selector) {
// For selector state, the ending and starting point of the selector is
// either when the state changes or the selector becomes empty and a
// single selector can span multiple lines.
// Backward loop to determine the beginning location of the selector.
let start = traverseBackwards(state => {
return (state != CSS_STATES.selector ||
(this.selector == "" && this.selectorBeforeNot == null));
});
line = caret.line;
limitedSource = limit(source, caret);
// Forward loop to determine the ending location of the selector.
let end = traverseForward(state => {
return (state != CSS_STATES.selector ||
(this.selector == "" && this.selectorBeforeNot == null));
});
// Since we have start and end positions, figure out the whole selector.
let selector = source.split("\n").slice(start.line, end.line + 1);
selector[selector.length - 1] =
selector[selector.length - 1].substring(0, end.ch);
selector[0] = selector[0].substring(start.ch);
selector = selector.join("\n");
return {
state: state,
selector: selector,
loc: {
start: start,
end: end
}
};
} else if (state == CSS_STATES.property) {
// A property can only be a single word and thus very easy to calculate.
let tokens = cssTokenizer(sourceArray[line]);
for (let token of tokens) {
// Note that, because we're tokenizing a single line, the
// token's offset is also the column number.
if (token.startOffset <= ch && token.endOffset >= ch) {
return {
state: state,
propertyName: token.text,
selectors: this.selectors,
loc: {
start: {
line: line,
ch: token.startOffset
},
end: {
line: line,
ch: token.endOffset
}
}
};
}
}
} else if (state == CSS_STATES.value) {
// CSS value can be multiline too, so we go forward and backwards to
// determine the bounds of the value at caret
let start = traverseBackwards(state => state != CSS_STATES.value, true);
line = caret.line;
limitedSource = limit(source, caret);
let end = traverseForward(state => state != CSS_STATES.value);
let value = source.split("\n").slice(start.line, end.line + 1);
value[value.length - 1] = value[value.length - 1].substring(0, end.ch);
value[0] = value[0].substring(start.ch);
value = value.join("\n");
return {
state: state,
propertyName: propertyName,
selectors: this.selectors,
value: value,
loc: {
start: start,
end: end
}
};
}
return null;
}