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   this work for additional information regarding copyright ownership.
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   (the "License"); you may not use this file except in compliance with
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   distributed under the License is distributed on an "AS IS" BASIS,
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package org.apache.poi.ss.formula.functions;

import org.apache.poi.ss.formula.CacheAreaEval;
import org.apache.poi.ss.formula.FormulaParseException;
import org.apache.poi.ss.formula.eval.*;

import java.util.function.BiFunction;

Author:
Robert Hulbert
Common Interface for any excel built-in function that has implemented array formula functionality./**
 * @author Robert Hulbert
 * Common Interface for any excel built-in function that has implemented array formula functionality.
 */

public interface ArrayFunction {
    
    
Params:
args – the evaluated function arguments. Empty values are represented with BlankEval or MissingArgEval, never null.
srcRowIndex – row index of the cell containing the formula under evaluation
srcColumnIndex – column index of the cell containing the formula under evaluation
Returns:
The evaluated result, possibly an ErrorEval, never null.
Note - Excel uses the error code #NUM! instead of IEEE NaN, so when numeric functions evaluate to Double.NaN be sure to translate the result to ErrorEval.NUM_ERROR./**
     * @param args the evaluated function arguments.  Empty values are represented with
     * {@link BlankEval} or {@link MissingArgEval}, never <code>null</code>.
     * @param srcRowIndex row index of the cell containing the formula under evaluation
     * @param srcColumnIndex column index of the cell containing the formula under evaluation
     * @return The evaluated result, possibly an {@link ErrorEval}, never <code>null</code>.
     * <b>Note</b> - Excel uses the error code <i>#NUM!</i> instead of IEEE <i>NaN</i>, so when
     * numeric functions evaluate to {@link Double#NaN} be sure to translate the result to {@link
     * ErrorEval#NUM_ERROR}.
     */

    ValueEval evaluateArray(ValueEval[] args, int srcRowIndex, int srcColumnIndex);

    
Evaluate an array function with two arguments.
Params:
arg0 – the first function argument. Empty values are represented with BlankEval or MissingArgEval, never null
arg1 – the first function argument. Empty values are represented with @link BlankEval} or MissingArgEval, never null
srcRowIndex – row index of the cell containing the formula under evaluation
srcColumnIndex – column index of the cell containing the formula under evaluation
Returns:
The evaluated result, possibly an ErrorEval, never null.
Note - Excel uses the error code #NUM! instead of IEEE NaN, so when numeric functions evaluate to Double.NaN be sure to translate the result to ErrorEval.NUM_ERROR./**
     * Evaluate an array function with two arguments.
     *
     * @param arg0 the first function argument. Empty values are represented with
     *        {@link BlankEval} or {@link MissingArgEval}, never <code>null</code>
     * @param arg1 the first function argument. Empty values are represented with
     *      @link BlankEval} or {@link MissingArgEval}, never <code>null</code>
     *
     * @param srcRowIndex row index of the cell containing the formula under evaluation
     * @param srcColumnIndex column index of the cell containing the formula under evaluation
     * @return The evaluated result, possibly an {@link ErrorEval}, never <code>null</code>.
     * <b>Note</b> - Excel uses the error code <i>#NUM!</i> instead of IEEE <i>NaN</i>, so when
     * numeric functions evaluate to {@link Double#NaN} be sure to translate the result to {@link
     * ErrorEval#NUM_ERROR}.
     */
    default ValueEval evaluateTwoArrayArgs(ValueEval arg0, ValueEval arg1, int srcRowIndex, int srcColumnIndex,
                                           BiFunction<ValueEval, ValueEval, ValueEval> evalFunc) {
        int w1, w2, h1, h2;
        int a1FirstCol = 0, a1FirstRow = 0;
        if (arg0 instanceof AreaEval) {
            AreaEval ae = (AreaEval)arg0;
            w1 = ae.getWidth();
            h1 = ae.getHeight();
            a1FirstCol = ae.getFirstColumn();
            a1FirstRow = ae.getFirstRow();
        } else if (arg0 instanceof RefEval){
            RefEval ref = (RefEval)arg0;
            w1 = 1;
            h1 = 1;
            a1FirstCol = ref.getColumn();
            a1FirstRow = ref.getRow();
        } else {
            w1 = 1;
            h1 = 1;
        }
        int a2FirstCol = 0, a2FirstRow = 0;
        if (arg1 instanceof AreaEval) {
            AreaEval ae = (AreaEval)arg1;
            w2 = ae.getWidth();
            h2 = ae.getHeight();
            a2FirstCol = ae.getFirstColumn();
            a2FirstRow = ae.getFirstRow();
        } else if (arg1 instanceof RefEval){
            RefEval ref = (RefEval)arg1;
            w2 = 1;
            h2 = 1;
            a2FirstCol = ref.getColumn();
            a2FirstRow = ref.getRow();
        } else {
            w2 = 1;
            h2 = 1;
        }

        int width = Math.max(w1, w2);
        int height = Math.max(h1, h2);

        ValueEval[] vals = new ValueEval[height * width];

        int idx = 0;
        for(int i = 0; i < height; i++){
            for(int j = 0; j < width; j++){
                ValueEval vA;
                try {
                    vA = OperandResolver.getSingleValue(arg0, a1FirstRow + i, a1FirstCol + j);
                } catch (FormulaParseException e) {
                    vA = ErrorEval.NAME_INVALID;
                } catch (EvaluationException e) {
                    vA = e.getErrorEval();
                } catch (RuntimeException e) {
                    if(e.getMessage().startsWith("Don't know how to evaluate name")){
                        vA = ErrorEval.NAME_INVALID;
                    } else {
                        throw e;
                    }
                }
                ValueEval vB;
                try {
                    vB = OperandResolver.getSingleValue(arg1, a2FirstRow + i, a2FirstCol + j);
                } catch (FormulaParseException e) {
                    vB = ErrorEval.NAME_INVALID;
                } catch (EvaluationException e) {
                    vB = e.getErrorEval();
                } catch (RuntimeException e) {
                    if(e.getMessage().startsWith("Don't know how to evaluate name")){
                        vB = ErrorEval.NAME_INVALID;
                    } else {
                        throw e;
                    }
                }
                if(vA instanceof ErrorEval){
                    vals[idx++] = vA;
                } else if (vB instanceof ErrorEval) {
                    vals[idx++] = vB;
                } else {
                    vals[idx++] = evalFunc.apply(vA, vB);
                }

            }
        }

        if (vals.length == 1) {
            return vals[0];
        }

        return new CacheAreaEval(srcRowIndex, srcColumnIndex, srcRowIndex + height - 1, srcColumnIndex + width - 1, vals);
    }

    default ValueEval evaluateOneArrayArg(ValueEval arg0, int srcRowIndex, int srcColumnIndex,
                                          java.util.function.Function<ValueEval, ValueEval> evalFunc){
        int w1, w2, h1, h2;
        int a1FirstCol = 0, a1FirstRow = 0;
        if (arg0 instanceof AreaEval) {
            AreaEval ae = (AreaEval)arg0;
            w1 = ae.getWidth();
            h1 = ae.getHeight();
            a1FirstCol = ae.getFirstColumn();
            a1FirstRow = ae.getFirstRow();
        } else if (arg0 instanceof RefEval){
            RefEval ref = (RefEval)arg0;
            w1 = 1;
            h1 = 1;
            a1FirstCol = ref.getColumn();
            a1FirstRow = ref.getRow();
        } else {
            w1 = 1;
            h1 = 1;
        }
        w2 = 1;
        h2 = 1;

        int width = Math.max(w1, w2);
        int height = Math.max(h1, h2);

        ValueEval[] vals = new ValueEval[height * width];

        int idx = 0;
        for(int i = 0; i < height; i++){
            for(int j = 0; j < width; j++){
                ValueEval vA;
                try {
                    vA = OperandResolver.getSingleValue(arg0, a1FirstRow + i, a1FirstCol + j);
                } catch (FormulaParseException e) {
                    vA = ErrorEval.NAME_INVALID;
                } catch (EvaluationException e) {
                    vA = e.getErrorEval();
                } catch (RuntimeException e) {
                    if(e.getMessage().startsWith("Don't know how to evaluate name")){
                        vA = ErrorEval.NAME_INVALID;
                    } else {
                        throw e;
                    }
                }
                vals[idx++] = evalFunc.apply(vA);
            }
        }

        if (vals.length == 1) {
            return vals[0];
        }

        return new CacheAreaEval(srcRowIndex, srcColumnIndex, srcRowIndex + height - 1, srcColumnIndex + width - 1, vals);

    }

}