com.ossuminc.riddl.utils.FileBuilder.scala Maven / Gradle / Ivy
/*
* Copyright 2019 Ossum, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
package com.ossuminc.riddl.utils
import scala.collection.mutable
/** A trait to build a string up for writing to a file. This provides the platform specific definition of newline, an nl
* function to insert a newline, and other functions for putting changes into the file content. The file is assumed to
* have a UTF-8 content type.
*/
trait FileBuilder {
protected[utils] val sb: mutable.StringBuilder = new mutable.StringBuilder()
protected val new_line: String = System.lineSeparator()
protected val spaces_per_level = 2
private var indent_level: Int = 0
/** The number of spaces at the current indent level */
protected def spc: String = {
" ".repeat(indent_level * spaces_per_level)
}
/**
* Increment the indent by one level
* @return
*/
def incr: this.type = {
indent_level += 1
this
}
/**
* Decrement the indent by one level
* @return
*/
def decr: this.type = {
require(indent_level >= 1, "unmatched indents")
indent_level -= 1
this
}
/** Append a newline character
* @return
* This object for call chaining
*/
def nl: this.type = { sb.append(new_line); this }
/** Append a string without indent or suffix
*
* @param str
* The string to append
* @return
* This object for call chaining
*/
def add(str: String): this.type = {
sb.append(str)
this
}
/** Append a line to the buffer without newlines or indentation
* @param text
* The text to be appended
* @return
* This object for call chaining
*/
def append(text: String): this.type = { sb.append(text); this }
/** Append a line to the buffer with a terminating newline. No prefix is inserted
* @param line
* The line to be appended
* @return
* This object for call chaining
*/
def addLine(line: String): this.type = { sb.append(spc).append(line).append(new_line); this }
/**
* Add just the indent spaces
* @return
* This object for call chaining
*/
def addIndent(): this.type = {
sb.append(s"$spc")
this
}
/** Append an indented line with newline at the end and a `level` width indent prefix. The indent will be done with
* `level` * `spaces-per-level` space characters.
* @param line
* The text of the line to be indented
* @return
* This object for call chaining
*/
def addIndent(line: String): this.type = {
sb.append(spc).append(line)
this
}
override def toString: String = sb.toString
/** Convert the buffer to a sequence of strings, one line per string
* @return
*/
def toLines: Seq[String] = sb.toString.split(new_line).toIndexedSeq
/** Completely erase the internal buffer
*/
def clear(): Unit = {
sb.clear()
indent_level = 0
}
}