func cleanConf()

in internal/ingress/controller/template/template.go [100:175]
72 lines of code
22 McCabe index (conditional complexity)

func cleanConf(in *bytes.Buffer, out *bytes.Buffer) error {
	depth := 0
	lineStarted := false
	emptyLineWritten := false
	state := stateCode
	for {
		c, err := in.ReadByte()
		if err != nil {
			if err == io.EOF {
				return nil
			}
			return err // unreachable
		}

		needOutput := false
		nextDepth := depth
		nextLineStarted := lineStarted

		switch state {
		case stateCode:
			switch c {
			case '{':
				needOutput = true
				nextDepth = depth + 1
				nextLineStarted = true
			case '}':
				needOutput = true
				depth--
				nextDepth = depth
				nextLineStarted = true
			case ' ', '\t':
				needOutput = lineStarted
			case '\r':
			case '\n':
				needOutput = !(!lineStarted && emptyLineWritten)
				nextLineStarted = false
			case '#':
				needOutput = true
				nextLineStarted = true
				state = stateComment
			default:
				needOutput = true
				nextLineStarted = true
			}
		case stateComment:
			switch c {
			case '\r':
			case '\n':
				needOutput = true
				nextLineStarted = false
				state = stateCode
			default:
				needOutput = true
			}
		}

		if needOutput {
			if !lineStarted && (writeIndentOnEmptyLines || c != '\n') {
				for i := 0; i < depth; i++ {
					err = out.WriteByte('\t') // always nil
					if err != nil {
						return err
					}
				}
			}
			emptyLineWritten = !lineStarted
			err = out.WriteByte(c) // always nil
			if err != nil {
				return err
			}
		}

		depth = nextDepth
		lineStarted = nextLineStarted
	}
}