package com.hubspot.jinjava.lib.filter;

import com.hubspot.jinjava.doc.annotations.JinjavaDoc;
import com.hubspot.jinjava.doc.annotations.JinjavaParam;
import com.hubspot.jinjava.doc.annotations.JinjavaSnippet;
import com.hubspot.jinjava.interpret.JinjavaInterpreter;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.math.NumberUtils;

@JinjavaDoc(
  value = "Uses whitespace to center the value in a field of a given width.",
  input = @JinjavaParam(value = "value", desc = "Value to center", required = true),
  params = {
    @JinjavaParam(
      value = "width",
      type = "number",
      defaultValue = "80",
      desc = "Width of field to center value in"
    )
  },
  snippets = {
    @JinjavaSnippet(
      desc = "Since HubSpot's compiler automatically strips whitespace, this filter will only work in tags where whitespace is retained, such as a <pre>",
      code = "<pre>\n" +
      "    {% set var = \"string to center\" %}\n" +
      "    {{ var|center(80) }}\n" +
      "</pre>"
    )
  }
)
public class CenterFilter implements Filter {

  @Override
  public String getName() {
    return "center";
  }

  @Override
  public Object filter(Object var, JinjavaInterpreter interpreter, String... args) {
    if (var == null) {
      return null;
    }

    int size = 80;
    if (args.length > 0) {
      size = NumberUtils.toInt(args[0], 80);
    }

    return StringUtils.center(var.toString(), size);
  }
}
