package sprigx

import (
	`strings`
)

/*
extIndent serves as a much more flexible alternative to the Sprig `indent`.

It has 6 arguments (the last of which may be passed in via pipeline):

	* levels: The level of indentation for the text. If less than or equal to `0`, `extIndent` just returns `<input>` as-is and NO-OPs otherwise.
	* skipFirst: If true, skip indenting the first line. This is particularly handy if you like to visually align your function calls in your templates.
	* skipEmpty: If true, do not add an indent to *empty* lines (where an "empty line" means "only has a linebreak").
	* skipWhitespace: If true, do not add an indent to lines that *only* consist of whitespace (spaces, tabs, etc.) and a linebreak.
	* indentString: The string to use as the "indent character". This can be any string, such as `" "`, `"\t"`, `"."`, `"|"`, `"=="` etc.
					(In fact, if indentString is set to "\n" and levels is always set to 1, this function can even be used to doubelspace text!)
	* input: The text to be indented. Because it is the last argument, `extIndent` works with pipelined text as well.

*/
func extIndent(levels int, skipFirst, skipEmpty, skipWhitespace bool, indentString, input string) (out string) {

	var idx int
	var pad string
	var line string
	var lines []string

	if levels <= 0 {
		out = input
		return
	}

	pad = strings.Repeat(indentString, levels)
	lines = strings.Split(input, "\n")

	for idx, line = range lines {
		if idx == 0 && skipFirst {
			continue
		}
		if skipWhitespace && strings.TrimSpace(line) == "" && line != "" {
			continue
		}
		if skipEmpty && (line == "" || line == "\r") {
			continue
		}
		lines[idx] = pad + line
	}

	out = strings.Join(lines, "\n")

	return
}