/*
 * Copyright 2000-2017 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.uast

import org.jetbrains.uast.internal.acceptList
import org.jetbrains.uast.internal.log
import org.jetbrains.uast.visitor.UastTypedVisitor
import org.jetbrains.uast.visitor.UastVisitor

/**
 * Represents a
 *
 * `for (initDeclarations; loopCondition; update) {
 *      // body
 *  }`
 *
 *  loop expression.
 */
interface UForExpression : ULoopExpression {
  /**
   * Returns the [UExpression] containing variable declarations, or null if the are no variables declared.
   */
  val declaration: UExpression?

  /**
   * Returns the loop condition, or null if the condition is empty.
   */
  val condition: UExpression?

  /**
   * Returns the loop update expression(s).
   */
  val update: UExpression?

  /**
   * Returns the identifier for the 'for' keyword.
   */
  val forIdentifier: UIdentifier

  override fun accept(visitor: UastVisitor) {
    if (visitor.visitForExpression(this)) return
    annotations.acceptList(visitor)
    declaration?.accept(visitor)
    condition?.accept(visitor)
    update?.accept(visitor)
    body.accept(visitor)
    visitor.afterVisitForExpression(this)
  }

  override fun <D, R> accept(visitor: UastTypedVisitor<D, R>, data: D) =
    visitor.visitForExpression(this, data)

  override fun asRenderString() = buildString {
    append("for (")
    declaration?.let { append(it.asRenderString()) }
    append("; ")
    condition?.let { append(it.asRenderString()) }
    append("; ")
    update?.let { append(it.asRenderString()) }
    append(") ")
    append(body.asRenderString())
  }

  override fun asLogString() = log()
}
