<?php

namespace PhpOffice\PhpSpreadsheet\Calculation\Database;

use PhpOffice\PhpSpreadsheet\Calculation\Calculation;
use PhpOffice\PhpSpreadsheet\Calculation\Functions;
use PhpOffice\PhpSpreadsheet\Calculation\Internal\WildcardMatch;

abstract class DatabaseAbstract
{
    /**
     * @param array $database
     * @param int|string $field
     * @param array $criteria
     *
     * @return null|float|int|string
     */
    abstract public static function evaluate($database, $field, $criteria);

    /**
     * fieldExtract.
     *
     * Extracts the column ID to use for the data field.
     *
     * @param mixed[] $database The range of cells that makes up the list or database.
     *                                        A database is a list of related data in which rows of related
     *                                        information are records, and columns of data are fields. The
     *                                        first row of the list contains labels for each column.
     * @param mixed $field Indicates which column is used in the function. Enter the
     *                                        column label enclosed between double quotation marks, such as
     *                                        "Age" or "Yield," or a number (without quotation marks) that
     *                                        represents the position of the column within the list: 1 for
     *                                        the first column, 2 for the second column, and so on.
     */
    protected static function fieldExtract(array $database, $field): ?int
    {
        $field = strtoupper(Functions::flattenSingleValue($field) ?? '');
        if ($field === '') {
            return null;
        }

        $fieldNames = array_map('strtoupper', array_shift($database));
        if (is_numeric($field)) {
            $field = (int) $field - 1;
            if ($field < 0 || $field >= count($fieldNames)) {
                return null;
            }

            return $field;
        }
        $key = array_search($field, array_values($fieldNames), true);

        return ($key !== false) ? (int) $key : null;
    }

    /**
     * filter.
     *
     * Parses the selection criteria, extracts the database rows that match those criteria, and
     * returns that subset of rows.
     *
     * @param mixed[] $database The range of cells that makes up the list or database.
     *                                        A database is a list of related data in which rows of related
     *                                        information are records, and columns of data are fields. The
     *                                        first row of the list contains labels for each column.
     * @param mixed[] $criteria The range of cells that contains the conditions you specify.
     *                                        You can use any range for the criteria argument, as long as it
     *                                        includes at least one column label and at least one cell below
     *                                        the column label in which you specify a condition for the
     *                                        column.
     *
     * @return mixed[]
     */
    protected static function filter(array $database, array $criteria): array
    {
        $fieldNames = array_shift($database);
        $criteriaNames = array_shift($criteria);

        //    Convert the criteria into a set of AND/OR conditions with [:placeholders]
        $query = self::buildQuery($criteriaNames, $criteria);

        //    Loop through each row of the database
        return self::executeQuery($database, $query, $criteriaNames, $fieldNames);
    }

    protected static function getFilteredColumn(array $database, ?int $field, array $criteria): array
    {
        //    reduce the database to a set of rows that match all the criteria
        $database = self::filter($database, $criteria);
        $defaultReturnColumnValue = ($field === null) ? 1 : null;

        //    extract an array of values for the requested column
        $columnData = [];
        foreach ($database as $rowKey => $row) {
            $keys = array_keys($row);
            $key = $keys[$field] ?? null;
            $columnKey = $key ?? 'A';
            $columnData[$rowKey][$columnKey] = $row[$key] ?? $defaultReturnColumnValue;
        }

        return $columnData;
    }

    private static function buildQuery(array $criteriaNames, array $criteria): string
    {
        $baseQuery = [];
        foreach ($criteria as $key => $criterion) {
            foreach ($criterion as $field => $value) {
                $criterionName = $criteriaNames[$field];
                if ($value !== null) {
                    $condition = self::buildCondition($value, $criterionName);
                    $baseQuery[$key][] = $condition;
                }
            }
        }

        $rowQuery = array_map(
            function ($rowValue) {
                return (count($rowValue) > 1) ? 'AND(' . implode(',', $rowValue) . ')' : ($rowValue[0] ?? '');
            },
            $baseQuery
        );

        return (count($rowQuery) > 1) ? 'OR(' . implode(',', $rowQuery) . ')' : ($rowQuery[0] ?? '');
    }

    /**
     * @param mixed $criterion
     */
    private static function buildCondition($criterion, string $criterionName): string
    {
        $ifCondition = Functions::ifCondition($criterion);

        // Check for wildcard characters used in the condition
        $result = preg_match('/(?<operator>[^"]*)(?<operand>".*[*?].*")/ui', $ifCondition, $matches);
        if ($result !== 1) {
            return "[:{$criterionName}]{$ifCondition}";
        }

        $trueFalse = ($matches['operator'] !== '<>');
        $wildcard = WildcardMatch::wildcard($matches['operand']);
        $condition = "WILDCARDMATCH([:{$criterionName}],{$wildcard})";
        if ($trueFalse === false) {
            $condition = "NOT({$condition})";
        }

        return $condition;
    }

    private static function executeQuery(array $database, string $query, array $criteria, array $fields): array
    {
        foreach ($database as $dataRow => $dataValues) {
            //    Substitute actual values from the database row for our [:placeholders]
            $conditions = $query;
            foreach ($criteria as $criterion) {
                $conditions = self::processCondition($criterion, $fields, $dataValues, $conditions);
            }

            //    evaluate the criteria against the row data
            $result = Calculation::getInstance()->_calculateFormulaValue('=' . $conditions);

            //    If the row failed to meet the criteria, remove it from the database
            if ($result !== true) {
                unset($database[$dataRow]);
            }
        }

        return $database;
    }

    /**
     * @return mixed
     */
    private static function processCondition(string $criterion, array $fields, array $dataValues, string $conditions)
    {
        $key = array_search($criterion, $fields, true);

        $dataValue = 'NULL';
        if (is_bool($dataValues[$key])) {
            $dataValue = ($dataValues[$key]) ? 'TRUE' : 'FALSE';
        } elseif ($dataValues[$key] !== null) {
            $dataValue = $dataValues[$key];
            // escape quotes if we have a string containing quotes
            if (is_string($dataValue) && strpos($dataValue, '"') !== false) {
                $dataValue = str_replace('"', '""', $dataValue);
            }
            $dataValue = (is_string($dataValue)) ? Calculation::wrapResult(strtoupper($dataValue)) : $dataValue;
        }

        return str_replace('[:' . $criterion . ']', $dataValue, $conditions);
    }
}