<?php

declare(strict_types=1);

namespace App\Controllers;

use App\Core\Access;
use App\Core\Csrf;
use App\Core\JsonResponse;
use App\Core\Request;
use App\Models\VacationModel;
use App\Services\SchoolHolidayApiService;
use DateTimeImmutable;
use PDO;
use Throwable;

final class VacationController
{
    private VacationModel $vacationModel;
    private Access $access;

    public function __construct(private PDO $pdo)
    {
        $this->vacationModel = new VacationModel($pdo);
        $this->access = new Access($pdo);
    }

    public function index(): void
    {
        $this->access->requireService();
        $schoolYear = trim((string) ($_GET['school_year'] ?? ''));
        if ($schoolYear !== '' && !$this->isSchoolYear($schoolYear)) {
            JsonResponse::send(422, ['error' => 'Année scolaire invalide. Format attendu : 2026-2027.']);
        }

        JsonResponse::send(200, [
            'periods' => $this->vacationModel->all($schoolYear !== '' ? $schoolYear : null),
        ]);
    }

    public function preview(): void
    {
        $this->access->requireService();
        $academy = trim((string) ($_GET['academy'] ?? ''));
        $calendarYearRaw = trim((string) ($_GET['year'] ?? ''));

        if ($academy === '' || (function_exists('mb_strlen') ? mb_strlen($academy, 'UTF-8') : strlen($academy)) > 100) {
            JsonResponse::send(422, ['error' => 'Renseignez une académie valide.']);
        }

        if (!preg_match('/^\d{4}$/', $calendarYearRaw)) {
            JsonResponse::send(422, ['error' => 'Année civile invalide. Format attendu : 2026.']);
        }
        $calendarYear = (int) $calendarYearRaw;
        if ($calendarYear < 2000 || $calendarYear > 2100) {
            JsonResponse::send(422, ['error' => 'Année civile invalide.']);
        }

        try {
            $result = (new SchoolHolidayApiService())->previewCalendarYearDetailed($academy, $calendarYear);
            $periods = $result['periods'];
            $warnings = $result['warnings'];
        } catch (Throwable $e) {
            JsonResponse::send(502, [
                'error' => 'Impossible de charger les propositions depuis l’API officielle.',
                'details' => (getenv('PTA_DEBUG') ?: '1') !== '0' ? $e->getMessage() : null,
            ]);
        }

        JsonResponse::send(200, [
            'academy' => $academy,
            'year' => $calendarYear,
            'periods' => $periods,
            'warnings' => $warnings ?? [],
            'message' => $periods === []
                ? 'Aucune période n’a été trouvée pour l’année ' . $calendarYear . '.'
                : sprintf('%d période%s proposée%s pour toute l’année %d. Aucune donnée n’a été enregistrée en base.', count($periods), count($periods) > 1 ? 's' : '', count($periods) > 1 ? 's' : '', $calendarYear),
        ]);
    }

    public function save(): void
    {
        $this->access->requireService();
        Request::requireMethod('POST');
        $payload = Request::json();
        Csrf::assertPayload($payload);

        $rawPeriods = $payload['periods'] ?? [];
        if (!is_array($rawPeriods) || $rawPeriods === []) {
            JsonResponse::send(422, ['error' => 'Sélectionnez au moins une période à enregistrer.']);
        }
        if (count($rawPeriods) > 50) {
            JsonResponse::send(422, ['error' => 'Trop de périodes ont été envoyées en une seule fois.']);
        }

        $periods = [];
        foreach ($rawPeriods as $index => $raw) {
            if (!is_array($raw)) {
                JsonResponse::send(422, ['error' => 'Période invalide à la ligne ' . ($index + 1) . '.']);
            }

            $label = trim((string) ($raw['libelle'] ?? ''));
            $start = trim((string) ($raw['date_debut'] ?? ''));
            $end = trim((string) ($raw['date_fin'] ?? ''));
            $schoolYear = trim((string) ($raw['annee_scolaire'] ?? ''));
            $academy = trim((string) ($raw['academie'] ?? ''));
            $zone = trim((string) ($raw['zone'] ?? ''));
            $source = strtoupper(trim((string) ($raw['source'] ?? 'MANUEL')));

            if ($label === '' || (function_exists('mb_strlen') ? mb_strlen($label, 'UTF-8') : strlen($label)) > 150 || !$this->isDate($start) || !$this->isDate($end) || $end < $start) {
                JsonResponse::send(422, ['error' => 'Dates ou libellé invalides à la ligne ' . ($index + 1) . '.']);
            }
            if (!$this->isSchoolYear($schoolYear)) {
                JsonResponse::send(422, ['error' => 'Année scolaire invalide à la ligne ' . ($index + 1) . '.']);
            }
            if (!in_array($source, ['MANUEL', 'DATA_GOUV'], true)) {
                $source = 'MANUEL';
            }

            $periods[] = [
                'libelle' => $label,
                'date_debut' => $start,
                'date_fin' => $end,
                'annee_scolaire' => $schoolYear,
                'academie' => function_exists('mb_substr') ? mb_substr($academy, 0, 100, 'UTF-8') : substr($academy, 0, 100),
                'zone' => function_exists('mb_substr') ? mb_substr($zone, 0, 50, 'UTF-8') : substr($zone, 0, 50),
                'source' => $source,
            ];
        }

        $count = $this->vacationModel->saveMany($periods);
        JsonResponse::send(200, [
            'success' => true,
            'count' => $count,
            'message' => sprintf('%d période%s de vacances enregistrée%s après validation manuelle.', $count, $count > 1 ? 's' : '', $count > 1 ? 's' : ''),
        ]);
    }

    public function delete(): void
    {
        $this->access->requireService();
        Request::requireMethod('POST');
        $payload = Request::json();
        Csrf::assertPayload($payload);

        $id = filter_var($payload['period_id'] ?? null, FILTER_VALIDATE_INT);
        if (!$id) {
            JsonResponse::send(422, ['error' => 'Période invalide.']);
        }
        if (!$this->vacationModel->delete((int) $id)) {
            JsonResponse::send(404, ['error' => 'Période introuvable.']);
        }

        JsonResponse::send(200, ['success' => true, 'message' => 'Période supprimée.']);
    }

    private function isDate(string $value): bool
    {
        $date = DateTimeImmutable::createFromFormat('!Y-m-d', $value);
        return $date !== false && $date->format('Y-m-d') === $value;
    }

    private function isSchoolYear(string $value): bool
    {
        if (!preg_match('/^(\d{4})-(\d{4})$/', $value, $matches)) {
            return false;
        }
        return (int) $matches[2] === (int) $matches[1] + 1;
    }
}