1package io.protobase.f7.formulas.text;
 2
 3import io.protobase.f7.errors.F7Exception;
 4import io.protobase.f7.formulas.AbstractFormula;
 5import io.protobase.f7.formulas.FormulaName;
 6import io.protobase.f7.models.GridColumnRowKey;
 7import io.protobase.f7.utils.Converters;
 8
 9import java.util.function.BiFunction;
10import java.util.function.Function;
11
12/**
13 * TODO/HACK
14 * In Google Sheets: =CONCAT({"Hello","One"}, {"There","Two"}) results in "HelloThere"
15 * In Excel:         =CONCAT({"Hello","One"}, {"There","Two"}) results in "HelloOneThereTwo"
16 * <p>
17 * "Fixing" this is tricky. Which one should be considered correct? Are we integrating with both?
18 */
19public class CONCAT extends AbstractFormula {
20  public static FormulaName NAME = FormulaName.CONCAT;
21  public static CONCAT SELF = new CONCAT();
22
23  public CONCAT() {
24    super();
25  }
26
27  public CONCAT(Function<Object, Object> lookup, BiFunction<GridColumnRowKey, Object, Object> collateralLookup) {
28    super(lookup, collateralLookup);
29  }
30
31  @Override
32  public Object internal(GridColumnRowKey origin, Object... values) {
33    checkLength(values.length, 2, NAME);
34    Object first = Converters.first(collateralLookup.apply(origin, values[0]));
35    Object second = Converters.first(collateralLookup.apply(origin, values[1]));
36    if (first instanceof F7Exception) {
37      return first;
38    }
39    if (second instanceof F7Exception) {
40      return second;
41    }
42    return Converters.toText(first) + Converters.toText(second);
43  }
44}