less-openui5
Version:
Build OpenUI5 themes with Less.js
218 lines (192 loc) • 7.96 kB
JavaScript
(function (tree) {
tree.toCSSVisitor = function(env) {
this._visitor = new tree.visitor(this);
this._env = env;
};
tree.toCSSVisitor.prototype = {
isReplacing: true,
run: function (root) {
return this._visitor.visit(root);
},
visitRule: function (ruleNode, visitArgs) {
if (ruleNode.variable) {
return [];
}
return ruleNode;
},
visitMixinDefinition: function (mixinNode, visitArgs) {
// mixin definitions do not get eval'd - this means they keep state
// so we have to clear that state here so it isn't used if toCSS is called twice
mixinNode.frames = [];
return [];
},
visitExtend: function (extendNode, visitArgs) {
return [];
},
visitComment: function (commentNode, visitArgs) {
if (commentNode.isSilent(this._env)) {
return [];
}
return commentNode;
},
visitMedia: function(mediaNode, visitArgs) {
mediaNode.accept(this._visitor);
visitArgs.visitDeeper = false;
if (!mediaNode.rules.length) {
return [];
}
return mediaNode;
},
visitDirective: function(directiveNode, visitArgs) {
if (directiveNode.currentFileInfo.reference && !directiveNode.isReferenced) {
return [];
}
if (directiveNode.name === "@charset") {
// Only output the debug info together with subsequent @charset definitions
// a comment (or @media statement) before the actual @charset directive would
// be considered illegal css as it has to be on the first line
if (this.charset) {
if (directiveNode.debugInfo) {
var comment = new tree.Comment("/* " + directiveNode.toCSS(this._env).replace(/\n/g, "")+" */\n");
comment.debugInfo = directiveNode.debugInfo;
return this._visitor.visit(comment);
}
return [];
}
this.charset = true;
}
return directiveNode;
},
checkPropertiesInRoot: function(rules) {
var ruleNode;
for(var i = 0; i < rules.length; i++) {
ruleNode = rules[i];
if (ruleNode instanceof tree.Rule && !ruleNode.variable) {
throw { message: "properties must be inside selector blocks, they cannot be in the root.",
index: ruleNode.index, filename: ruleNode.currentFileInfo ? ruleNode.currentFileInfo.filename : null};
}
}
},
visitRuleset: function (rulesetNode, visitArgs) {
var rule, rulesets = [];
if (rulesetNode.firstRoot) {
this.checkPropertiesInRoot(rulesetNode.rules);
}
if (! rulesetNode.root) {
if (rulesetNode.paths) {
rulesetNode.paths = rulesetNode.paths
.filter(function(p) {
var i;
if (p[0].elements[0].combinator.value === ' ') {
p[0].elements[0].combinator = new(tree.Combinator)('');
}
for(i = 0; i < p.length; i++) {
if (p[i].getIsReferenced() && p[i].getIsOutput()) {
return true;
}
}
return false;
});
}
// Compile rules and rulesets
var nodeRules = rulesetNode.rules, nodeRuleCnt = nodeRules ? nodeRules.length : 0;
for (var i = 0; i < nodeRuleCnt; ) {
rule = nodeRules[i];
if (rule && rule.rules) {
// visit because we are moving them out from being a child
rulesets.push(this._visitor.visit(rule));
nodeRules.splice(i, 1);
nodeRuleCnt--;
continue;
}
i++;
}
// accept the visitor to remove rules and refactor itself
// then we can decide now whether we want it or not
if (nodeRuleCnt > 0) {
rulesetNode.accept(this._visitor);
} else {
rulesetNode.rules = null;
}
visitArgs.visitDeeper = false;
nodeRules = rulesetNode.rules;
if (nodeRules) {
this._mergeRules(nodeRules);
nodeRules = rulesetNode.rules;
}
if (nodeRules) {
this._removeDuplicateRules(nodeRules);
nodeRules = rulesetNode.rules;
}
// now decide whether we keep the ruleset
if (nodeRules && nodeRules.length > 0 && rulesetNode.paths.length > 0) {
rulesets.splice(0, 0, rulesetNode);
}
} else {
rulesetNode.accept(this._visitor);
visitArgs.visitDeeper = false;
if (rulesetNode.firstRoot || (rulesetNode.rules && rulesetNode.rules.length > 0)) {
rulesets.splice(0, 0, rulesetNode);
}
}
if (rulesets.length === 1) {
return rulesets[0];
}
return rulesets;
},
_removeDuplicateRules: function(rules) {
if (!rules) { return; }
// remove duplicates
var ruleCache = {},
ruleList, rule, i;
for(i = rules.length - 1; i >= 0 ; i--) {
rule = rules[i];
if (rule instanceof tree.Rule) {
if (!ruleCache[rule.name]) {
ruleCache[rule.name] = rule;
} else {
ruleList = ruleCache[rule.name];
if (ruleList instanceof tree.Rule) {
ruleList = ruleCache[rule.name] = [ruleCache[rule.name].toCSS(this._env)];
}
var ruleCSS = rule.toCSS(this._env);
if (ruleList.indexOf(ruleCSS) !== -1) {
rules.splice(i, 1);
} else {
ruleList.push(ruleCSS);
}
}
}
}
},
_mergeRules: function (rules) {
if (!rules) { return; }
var groups = {},
parts,
rule,
key;
for (var i = 0; i < rules.length; i++) {
rule = rules[i];
if ((rule instanceof tree.Rule) && rule.merge) {
key = [rule.name,
rule.important ? "!" : ""].join(",");
if (!groups[key]) {
groups[key] = [];
} else {
rules.splice(i--, 1);
}
groups[key].push(rule);
}
}
Object.keys(groups).map(function (k) {
parts = groups[k];
if (parts.length > 1) {
rule = parts[0];
rule.value = new (tree.Value)(parts.map(function (p) {
return p.value;
}));
}
});
}
};
})(require('./tree'));