/*
* Copyright 2010-2017 JetBrains s.r.o.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jetbrains.kotlin.js.inline.clean
import org.jetbrains.kotlin.js.backend.ast.*
import org.jetbrains.kotlin.js.inline.util.getImportTag
import org.jetbrains.kotlin.js.inline.util.replaceNames
fun removeDuplicateImports(node: JsNode) {
node.accept(object : RecursiveJsVisitor() {
override fun visitBlock(x: JsBlock) {
super.visitBlock(x)
removeDuplicateImports(x.statements)
}
})
}
private fun removeDuplicateImports(statements: MutableList<JsStatement>) {
val existingImports = mutableMapOf<String, JsName>()
val replacements = mutableMapOf<JsName, JsExpression>()
removeDuplicateImports(statements, existingImports, replacements)
for (statement in statements) {
replaceNames(statement, replacements)
}
}
private fun removeDuplicateImports(
statements: MutableList<JsStatement>,
existingImports: MutableMap<String, JsName>,
replacements: MutableMap<JsName, JsExpression>
) {
var index = 0
while (index < statements.size) {
val statement = statements[index]
if (statement is JsVars) {
val importTag = getImportTag(statement)
if (importTag != null) {
val name = statement.vars[0].name
val existingName = existingImports[importTag]
if (existingName != null) {
replacements[name] = existingName.makeRef()
statements.removeAt(index)
continue
}
else {
existingImports[importTag] = name
}
}
}
else if (statement is JsBlock) {
removeDuplicateImports(statement.statements, existingImports, replacements)
}
index++
}
}