<?php

/**
 * Matomo - free/libre analytics platform
 *
 * @link    https://matomo.org
 * @license https://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
 */
namespace Piwik\Plugins\API;

use Piwik\Metrics;
class Glossary
{
    /**
     * @var API
     */
    private $api;
    public function __construct(\Piwik\Plugins\API\API $api)
    {
        $this->api = $api;
    }
    public function reportsGlossary($idSite)
    {
        $metadata = $this->api->getReportMetadata($idSite);
        $reports = array();
        foreach ($metadata as $report) {
            if (isset($report['documentation'])) {
                $docReport = array('name' => sprintf("%s (%s)", $report['name'], $report['category']), 'documentation' => $report['documentation']);
                if (isset($report['onlineGuideUrl'])) {
                    $docReport['onlineGuideUrl'] = $report['onlineGuideUrl'];
                }
                $reports[] = $docReport;
            }
        }
        usort($reports, function ($a, $b) {
            return strcmp($a['name'], $b['name']);
        });
        return $reports;
    }
    public function metricsGlossary($idSite)
    {
        $metadata = $this->api->getReportMetadata($idSite);
        $metrics = [];
        // Add default values
        $metricsTranslations = Metrics::getDefaultMetricTranslations();
        foreach (Metrics::getDefaultMetricsDocumentation() as $metric => $translation) {
            // Don't show nb_hits in glossary since it duplicates others, eg. nb_downloads,
            if ($metric == 'nb_hits') {
                continue;
            }
            $metrics[$metric] = ['name' => $metricsTranslations[$metric], 'id' => $metric, 'documentation' => ['default' => $translation, 'reportSpecific' => []]];
        }
        foreach ($metadata as $report) {
            if (!isset($report['metricsDocumentation'])) {
                continue;
            }
            foreach ($report['metricsDocumentation'] as $metricId => $metricDocumentation) {
                $metricKey = $metricId;
                if (empty($report['metrics'][$metricId]) && empty($report['processedMetrics'][$metricId])) {
                    continue;
                }
                $metricName = $report['metrics'][$metricId] ?? $report['processedMetrics'][$metricId];
                // Already one metric with same name, but different documentation...
                if (isset($metrics[$metricKey]) && $metrics[$metricKey]['documentation']['default'] !== $metricDocumentation) {
                    // Don't show nb_hits in glossary since it duplicates others, eg. nb_downloads,
                    if ($metricKey == 'nb_hits') {
                        continue;
                    }
                    $metrics[$metricKey]['documentation']['reportSpecific'][$report['uniqueId']] = $metricDocumentation;
                } elseif (!isset($metrics[$metricKey])) {
                    $metrics[$metricKey] = ['name' => $metricName, 'id' => $metricId, 'documentation' => ['default' => null, 'reportSpecific' => [$report['uniqueId'] => $metricDocumentation]]];
                }
            }
        }
        foreach ($metrics as &$metric) {
            if (empty($metric['documentation']['default'])) {
                $valueCount = array_count_values($metric['documentation']['reportSpecific']);
                // in case we do not have a default set, but more than the half of all reports are using the same documentation, we assume that as default.
                if (array_sum($valueCount) - reset($valueCount) < reset($valueCount)) {
                    $metric['documentation']['default'] = key($valueCount);
                    foreach ($metric['documentation']['reportSpecific'] as $uniqueId => $documentation) {
                        if ($documentation === $metric['documentation']['default']) {
                            unset($metric['documentation']['reportSpecific'][$uniqueId]);
                        }
                    }
                }
            }
            if (empty($metric['documentation']['reportSpecific'])) {
                $metric['documentation']['reportSpecific'] = null;
            }
        }
        // convert back to structure with only one metric documentation
        // discarding all metrics that don't have a default documentation
        // @todo remove with Matomo 6 and provide report specific documentation where available
        foreach ($metrics as $metricId => &$metric) {
            if (empty($metric['documentation']['default'])) {
                unset($metrics[$metricId]);
            } else {
                $metric['documentation'] = $metric['documentation']['default'];
            }
        }
        usort($metrics, function ($a, $b) {
            $key = $a['name'] === $b['name'] ? 'id' : 'name';
            return strcmp($a[$key], $b[$key]);
        });
        return $metrics;
    }
}
