<?php

declare(strict_types=1);

final class StatisticsController
{
    public static function index(): void
    {
        $years = StatisticsService::years();
        $requestedYear = (string) ($_GET['year'] ?? date('Y'));
        $periodType = (string) ($_GET['period_type'] ?? ($requestedYear === 'all' ? 'all' : 'year'));
        if (!in_array($periodType, ['all','year','month','custom'], true)) {
            $periodType = 'year';
        }
        $year = max(2000, min(2200, (int) ($requestedYear === 'all' ? date('Y') : $requestedYear)));
        $month = preg_match('/^\d{4}-(0[1-9]|1[0-2])$/', (string) ($_GET['month'] ?? ''))
            ? (string) $_GET['month']
            : date('Y-m');
        $validDate = static function (string $value): bool {
            $date = DateTimeImmutable::createFromFormat('!Y-m-d', $value);
            return $date !== false && $date->format('Y-m-d') === $value;
        };
        $dateFrom = $validDate((string) ($_GET['date_from'] ?? '')) ? (string) $_GET['date_from'] : date('Y-01-01');
        $dateTo = $validDate((string) ($_GET['date_to'] ?? '')) ? (string) $_GET['date_to'] : date('Y-m-d');
        if ($dateFrom > $dateTo) {
            [$dateFrom, $dateTo] = [$dateTo, $dateFrom];
        }
        $start = $end = null;
        if ($periodType === 'year') {
            $start = sprintf('%04d-01-01', $year);
            $end = sprintf('%04d-12-31', $year);
        } elseif ($periodType === 'month') {
            $start = $month . '-01';
            $end = (new DateTimeImmutable($start))->modify('last day of this month')->format('Y-m-d');
            $year = (int) substr($month, 0, 4);
        } elseif ($periodType === 'custom') {
            $start = $dateFrom;
            $end = $dateTo;
            $year = (int) substr($dateFrom, 0, 4);
        }
        $all = $periodType === 'all';
        $formatDate = static fn(string $date): string => (new DateTimeImmutable($date))->format('d/m/Y');
        $periodLabel = match ($periodType) {
            'all' => t('statistics.all_years'),
            'month' => substr($month, 5, 2) . '/' . substr($month, 0, 4),
            'custom' => $formatDate($dateFrom) . ' – ' . $formatDate($dateTo),
            default => (string) $year,
        };
        $periodQuery = ['period_type' => $periodType];
        if ($periodType === 'year') $periodQuery['year'] = $year;
        if ($periodType === 'month') $periodQuery['month'] = $month;
        if ($periodType === 'custom') $periodQuery += ['date_from' => $dateFrom,'date_to' => $dateTo];
        $municipalities = StatisticsService::municipalities();
        $municipality = trim((string) ($_GET['municipality'] ?? ''));
        if ($municipality !== '' && !isset($municipalities[$municipality])) {
            $municipality = '';
        }
        $ids = $municipality !== '' ? StatisticsService::animalIdsForMunicipality($municipality) : null;
        if ($all) {
            $comparison = [];
            $previousPeriodLabel = '';
        } elseif ($periodType === 'year') {
            $comparison = StatisticsService::comparison($year, $ids);
            $previousPeriodLabel = (string) ($year - 1);
        } else {
            $comparisonResult = StatisticsService::comparisonPeriod($start, $end, $ids);
            $comparison = $comparisonResult['rows'];
            $previousPeriodLabel = $formatDate($comparisonResult['previous_start']) . ' – ' . $formatDate($comparisonResult['previous_end']);
        }
        render('statistics.php', [
            'title' => t('statistics.title'),
            'pageDescription' => t('statistics.description'),
            'year' => $year,
            'allYears' => $all,
            'periodType' => $periodType,
            'month' => $month,
            'dateFrom' => $dateFrom,
            'dateTo' => $dateTo,
            'periodLabel' => $periodLabel,
            'previousPeriodLabel' => $previousPeriodLabel,
            'periodQuery' => $periodQuery,
            'years' => $years,
            'municipality' => $municipality,
            'municipalities' => $municipalities,
            'municipalityCoverage' => StatisticsService::municipalityCoverage(),
            'stats' => $all ? StatisticsService::all($ids) : StatisticsService::period($start, $end, $ids),
            'comparison' => $comparison,
            'timeline' => StatisticsService::timeline($years, $ids),
            'undatedHandled' => StatisticsService::undatedHandled($ids),
            'undatedDeaths' => StatisticsService::undatedDeaths($ids),
            'undatedBirths' => StatisticsService::undatedBirths($ids),
            'undatedExits' => StatisticsService::undatedExits($ids),
            'scopeCounts' => StatisticsService::scopeCounts($ids),
            'distributions' => StatisticsService::distributions($all ? null : $year, $ids, $municipality ?: null, $start, $end),
            'health' => StatisticsService::currentHealth($ids),
            'costs' => StatisticsService::costs($all ? null : $year, $ids, $start, $end),
            'municipalityCosts' => StatisticsService::costsByMunicipality($all ? null : $year, $start, $end),
        ]);
    }
}