<?php

/**
 * Matomo - free/libre analytics platform
 *
 * @link https://matomo.org
 * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
 *
 */

namespace Piwik\Plugins\CustomVariables\RecordBuilders;

use Piwik\ArchiveProcessor;
use Piwik\ArchiveProcessor\Record;
use Piwik\ArchiveProcessor\RecordBuilder;
use Piwik\Config;
use Piwik\DataAccess\LogAggregator;
use Piwik\DataTable;
use Piwik\DbHelper;
use Piwik\Metrics;
use Piwik\Plugins\CustomVariables\API;
use Piwik\Plugins\CustomVariables\Archiver;
use Piwik\Plugins\CustomVariables\Model;
use Piwik\Tracker\GoalManager;
use Piwik\Version;

class CustomVariables extends RecordBuilder
{
    public function __construct()
    {
        parent::__construct();

        $this->maxRowsInTable = Config::getInstance()->General['datatable_archiving_maximum_rows_custom_variables']
            ?? Config::getInstance()->General['datatable_archiving_maximum_rows_custom_dimensions'];
        $this->maxRowsInSubtable = Config::getInstance()->General['datatable_archiving_maximum_rows_subtable_custom_variables']
            ?? Config::getInstance()->General['datatable_archiving_maximum_rows_subtable_custom_dimensions'];
        $this->columnToSortByBeforeTruncation = Metrics::INDEX_NB_VISITS;
        $this->columnAggregationOps = ['slots' => 'uniquearraymerge'];
    }

    public function getRecordMetadata(ArchiveProcessor $archiveProcessor): array
    {
        return [
            Record::make(Record::TYPE_BLOB, Archiver::CUSTOM_VARIABLE_RECORD_NAME),
        ];
    }

    protected function aggregate(ArchiveProcessor $archiveProcessor): array
    {
        $record = new DataTable();
        $metadata = [];
        $metadataFlat = [];

        $logAggregator = $archiveProcessor->getLogAggregator();

        $maxCustomVariables = \Piwik\Plugins\CustomVariables\CustomVariables::getNumUsableCustomVariables();
        for ($i = 1; $i <= $maxCustomVariables; $i++) {
            $this->aggregateCustomVariable($record, $metadata, $metadataFlat, $logAggregator, $i);
        }

        $this->removeVisitsMetricsFromActionsAggregate($record);
        $record->filter(DataTable\Filter\EnrichRecordWithGoalMetricSums::class);

        foreach ($record->getRows() as $row) {
            $label = $row->getColumn('label');
            if (!empty($metadata[$label])) {
                foreach ($metadata[$label] as $name => $value) {
                    $row->addMetadata($name, $value);
                }
            }
        }

        return [Archiver::CUSTOM_VARIABLE_RECORD_NAME => $record];
    }


    protected function aggregateCustomVariable(DataTable $record, array &$metadata, array &$metadataFlat, LogAggregator $logAggregator, string $slot): void
    {
        $keyField = "custom_var_k" . $slot;
        $valueField = "custom_var_v" . $slot;
        $where = "%s.$keyField != ''";
        $dimensions = array($keyField, $valueField);

        $query = $logAggregator->queryVisitsByDimension($dimensions, $where);
        $this->aggregateFromVisits($record, $metadata, $metadataFlat, $query, $keyField, $valueField);

        // IF we query Custom Variables scope "page" either: Product SKU, Product Name,
        // then we also query the "Product page view" price which was possibly recorded.
        $additionalSelects = false;

        // Before Matomo 4.0.0 ecommerce views were tracked in custom variables
        // So if Matomo was installed before still try to archive it the old way, as old data might be archived
        if (version_compare(DbHelper::getInstallVersion(), '4.0.0-b2', '<') && in_array($slot, array(3, 4, 5))) {
            $additionalSelects = array($this->getSelectAveragePrice());
        }
        $query = $logAggregator->queryActionsByDimension($dimensions, $where, $additionalSelects);
        $this->aggregateFromActions($record, $metadata, $metadataFlat, $query, $keyField, $valueField);

        $query = version_compare(Version::VERSION, '5.2.0-b6', '>=')
            ? $logAggregator->queryConversionsByDimension($dimensions, $where, [], [], false, false, true)
            : $logAggregator->queryConversionsByDimension($dimensions, $where);
        $this->aggregateFromConversions($record, $query, $keyField, $valueField);
    }

    protected function getSelectAveragePrice()
    {
        $field = "custom_var_v2";
        return LogAggregator::getSqlRevenue("AVG(log_link_visit_action." . $field . ")") . " as `" . Metrics::INDEX_ECOMMERCE_ITEM_PRICE_VIEWED . "`";
    }

    protected function aggregateFromVisits(
        DataTable $record,
        array &$metadata,
        array &$metadataFlat,
        $query,
        string $keyField,
        string $valueField
    ): void {
        while ($row = $query->fetch()) {
            $key = $row[$keyField];
            $value = $this->cleanCustomVarValue($row[$valueField]);

            $this->addMetadata($metadata, $metadataFlat, $keyField, $key, Model::SCOPE_VISIT);

            $columns = [
                Metrics::INDEX_NB_UNIQ_VISITORS => $row[Metrics::INDEX_NB_UNIQ_VISITORS],
                Metrics::INDEX_NB_VISITS => $row[Metrics::INDEX_NB_VISITS],
                Metrics::INDEX_NB_ACTIONS => $row[Metrics::INDEX_NB_ACTIONS],
                Metrics::INDEX_NB_USERS => $row[Metrics::INDEX_NB_USERS],
                Metrics::INDEX_MAX_ACTIONS => $row[Metrics::INDEX_MAX_ACTIONS],
                Metrics::INDEX_SUM_VISIT_LENGTH => $row[Metrics::INDEX_SUM_VISIT_LENGTH],
                Metrics::INDEX_BOUNCE_COUNT => $row[Metrics::INDEX_BOUNCE_COUNT],
                Metrics::INDEX_NB_VISITS_CONVERTED => $row[Metrics::INDEX_NB_VISITS_CONVERTED],
            ];

            $existingRow = $record->getRowFromLabel($key);

            // Edge case fail safe
            if (
                !empty($existingRow)
                && !$existingRow->hasColumn(Metrics::INDEX_NB_VISITS)
            ) {
                continue;
            }

            // In case the existing Row had no action metrics (eg. Custom Variable XYZ with "visit" scope)
            // but the new Row has action metrics (eg. same Custom Variable XYZ this time with a "page" scope)
            if (
                !empty($existingRow)
                && !$existingRow->hasColumn(Metrics::INDEX_MAX_ACTIONS)
            ) {
                $toZero = [
                    Metrics::INDEX_NB_USERS,
                    Metrics::INDEX_MAX_ACTIONS,
                    Metrics::INDEX_SUM_VISIT_LENGTH,
                    Metrics::INDEX_BOUNCE_COUNT,
                    Metrics::INDEX_NB_VISITS_CONVERTED,
                ];
                foreach ($toZero as $metric) {
                    $existingRow->setColumn($metric, 0);
                }
            }

            $topLevelRow = $record->sumRowWithLabel($key, $columns);
            $topLevelRow->sumRowWithLabelToSubtable($value, $columns);
        }
    }

    protected function cleanCustomVarValue($value)
    {
        if ($value !== null && strlen($value)) {
            return $value;
        }
        return Archiver::LABEL_CUSTOM_VALUE_NOT_DEFINED;
    }

    protected function aggregateFromActions(
        DataTable $record,
        array &$metadata,
        array &$metadataFlat,
        $query,
        string $keyField,
        string $valueField
    ): void {
        while ($row = $query->fetch()) {
            $key = $row[$keyField];
            $value = $this->cleanCustomVarValue($row[$valueField]);

            $this->addMetadata($metadata, $metadataFlat, $keyField, $key, Model::SCOPE_PAGE);

            $alreadyAggregated = $this->aggregateEcommerceCategories($record, $key, $value, $row);
            if (!$alreadyAggregated) {
                $this->aggregateActionByKeyAndValue($record, $key, $value, $row);

                $columns = [
                    Metrics::INDEX_NB_UNIQ_VISITORS => $row[Metrics::INDEX_NB_UNIQ_VISITORS],
                    Metrics::INDEX_NB_VISITS => $row[Metrics::INDEX_NB_VISITS],
                    Metrics::INDEX_NB_ACTIONS => $row[Metrics::INDEX_NB_ACTIONS],
                ];
                $record->sumRowWithLabel($key, $columns);
            }
        }
    }

    private function addMetadata(array &$metadata, array &$metadataFlat, string $keyField, string $label, string $scope): void
    {
        $index = (int) str_replace('custom_var_k', '', $keyField);

        if (!array_key_exists($label, $metadata)) {
            $metadata[$label] = array('slots' => array());
        }

        $uniqueId = $label . 'scope' . $scope . 'index' . $index;

        if (!isset($metadataFlat[$uniqueId])) {
            $metadata[$label]['slots'][] = array('scope' => $scope, 'index' => $index);
            $metadataFlat[$uniqueId] = true;
        }
    }

    /**
     * @param string $key
     * @param string $value
     * @param $row
     * @return bool True if the $row metrics were already added to the ->metrics
     */
    protected function aggregateEcommerceCategories(DataTable $record, string $key, string $value, array $row): bool
    {
        $ecommerceCategoriesAggregated = false;
        if (
            $key == '_pkc'
            && $value[0] == '[' && $value[1] == '"'
        ) {
            // In case categories were truncated, try closing the array
            if (substr($value, -2) != '"]') {
                $value .= '"]';
            }
            $decoded = json_decode($value);
            if (is_array($decoded)) {
                $count = 0;
                foreach ($decoded as $category) {
                    if (
                        empty($category)
                        || $count >= GoalManager::MAXIMUM_PRODUCT_CATEGORIES
                    ) {
                        continue;
                    }
                    $this->aggregateActionByKeyAndValue($record, $key, $category, $row);
                    $ecommerceCategoriesAggregated = true;
                    $count++;
                }
            }
        }
        return $ecommerceCategoriesAggregated;
    }

    protected function aggregateActionByKeyAndValue(DataTable $record, string $key, string $value, array $row): void
    {
        $columns = [
            Metrics::INDEX_NB_UNIQ_VISITORS => $row[Metrics::INDEX_NB_UNIQ_VISITORS],
            Metrics::INDEX_NB_VISITS => $row[Metrics::INDEX_NB_VISITS],
            Metrics::INDEX_NB_ACTIONS => $row[Metrics::INDEX_NB_ACTIONS],
        ];

        $toplevelRow = $record->sumRowWithLabel($key, []);

        // Edge case fail safe
        $subtable = $toplevelRow->getSubtable();
        $existingRow = !empty($subtable) ? $subtable->getRowFromLabel($value) : null;
        if (
            !empty($existingRow)
            && !$existingRow->hasColumn(Metrics::INDEX_NB_VISITS)
        ) {
            return;
        }

        $subtableRow = $toplevelRow->sumRowWithLabelToSubtable($value, $columns);

        if ($this->isReservedKey($key)) {
            // Price tracking on Ecommerce product/category pages:
            // the average is returned from the SQL query so the price is not "summed" like other metrics
            $index = Metrics::INDEX_ECOMMERCE_ITEM_PRICE_VIEWED;
            if (!empty($row[$index])) {
                $subtableRow->setColumn($index, (float)$row[$index]);
            }
        }
    }

    protected static function isReservedKey($key)
    {
        return in_array($key, API::getReservedCustomVariableKeys());
    }

    protected function aggregateFromConversions(DataTable $record, $query, string $keyField, string $valueField): void
    {
        if ($query === false) {
            return;
        }

        while ($row = $query->fetch()) {
            $key = $row[$keyField];

            $value = $this->cleanCustomVarValue($row[$valueField]);

            $idGoal = (int) $row['idgoal'];
            $columns = [
                Metrics::INDEX_GOALS => [
                    $idGoal => Metrics::makeGoalColumnsRow($idGoal, $row),
                ],
            ];

            $topLevelRow = $record->sumRowWithLabel($key, $columns);
            $topLevelRow->sumRowWithLabelToSubtable($value, $columns);
        }
    }

    /**
     * Delete Visit, Unique Visitor and Users metric from 'page' scope custom variables.
     *
     * - Custom variables of 'visit' scope: it is expected that these ones have the "visit" column set.
     * - Custom variables of 'page' scope: we cannot process "Visits" count for these.
     *   Why?
     *     "Actions" column is processed with a SELECT count(*).
     *     A same visit can set the same custom variable of 'page' scope multiple times.
     *     We cannot sum the values of count(*) as it would be incorrect.
     *     The way we could process "Visits" Metric for 'page' scope variable is to issue a count(Distinct *) or so,
     *     but it is no implemented yet (this would likely be very slow for high traffic sites).
     *
     */
    protected function removeVisitsMetricsFromActionsAggregate(DataTable $record): void
    {
        foreach ($record->getRows() as $row) {
            $label = $row->getColumn('label');
            if (
                !self::isReservedKey($label)
                && $this->isActionsRow($row)
            ) {
                $row->deleteColumn(Metrics::INDEX_NB_UNIQ_VISITORS);
                $row->deleteColumn(Metrics::INDEX_NB_VISITS);
                $row->deleteColumn(Metrics::INDEX_NB_USERS);
            }
        }
    }

    private function isActionsRow(DataTable\Row $row): bool
    {
        return count($row->getColumns()) == 4 && $row->hasColumn(Metrics::INDEX_NB_ACTIONS);
    }
}